├── media └── logo.png ├── Cask ├── .gitignore ├── test ├── test-helper.el └── json-rpc-server-test.el ├── README.md ├── json-rpc-server.el └── LICENSE /media/logo.png: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/jcaw/json-rpc-server.el/HEAD/media/logo.png -------------------------------------------------------------------------------- /Cask: -------------------------------------------------------------------------------- 1 | (source gnu) 2 | (source melpa) 3 | 4 | ;; (package-file "TODO") 5 | 6 | (development 7 | (depends-on "f") 8 | (depends-on "ecukes") 9 | (depends-on "ert-runner") 10 | (depends-on "el-mock") 11 | (depends-on "cl-lib")) 12 | -------------------------------------------------------------------------------- /.gitignore: -------------------------------------------------------------------------------- 1 | ## Elisp Ignores 2 | ## ------------- 3 | 4 | # Compiled 5 | *.elc 6 | 7 | # Packaging 8 | .cask 9 | 10 | # Backup files 11 | *~ 12 | 13 | # Undo-tree save-files 14 | *.~undo-tree 15 | 16 | 17 | ## Python Ignores 18 | ## -------------- 19 | *.ropeproject 20 | *__pycache__ 21 | *.pyc -------------------------------------------------------------------------------- /test/test-helper.el: -------------------------------------------------------------------------------- 1 | ;;; test-helper.el --- Helpers for json-rpc-server-test.el 2 | 3 | 4 | (defun json-rpc-server--structs-equal (instance1 instance2) 5 | "Compare two structs. Are they equal? 6 | 7 | Equality here means all of the following are true: 8 | 9 | - Both `INSTANCE1' and `INSTANCE2' are the same type of struct 10 | 11 | - Every slot in `INSTANCE1' is equal to the same slot in 12 | `INSTANCE2', according to cl-equal. 13 | 14 | An error will be raised if a type other than `cl-struct' is 15 | provided. 16 | 17 | This method gets around a quirk in normal struct comparison where 18 | two equivalent structs will not count as equal." 19 | (unless (cl-struct-p instance1) 20 | (error "`instance1' not a cl-struct")) 21 | (unless (cl-struct-p instance2) 22 | (error "`instance2' not a cl-struct")) 23 | (and 24 | ;; Ensure they're both the same type of object 25 | (eq (type-of instance1) 26 | (type-of instance2)) 27 | ;; Ensure every property is the same. 28 | (let ((struct-type 29 | ;; Remember - they have the same type. 30 | (type-of instance1))) 31 | (cl-every 32 | (lambda (slot-pair) 33 | ;; Ensure this slot is the same in both instances 34 | (let ((slot-name (car slot-pair))) 35 | (cl-equalp (cl-struct-slot-value struct-type slot-name instance1) 36 | (cl-struct-slot-value struct-type slot-name instance2)))) 37 | ;; Map over all slot names 38 | (cdr (cl-struct-slot-info struct-type)))))) 39 | 40 | ;;; test-helper.el ends here 41 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 |

2 | json-rpc-server logo 3 |

4 | 5 |

JSON-RPC-Server

6 | 7 |

Server-side implementation of the JSON-RPC 2.0 protocol for Emacs.

8 | 9 |

10 | 11 | 🔌 12 |

13 | 14 | --- 15 | 16 | 17 | 18 | This is a full implementation of the [JSON-RPC 19 | 2.0](https://www.jsonrpc.org/specification) protocol for Emacs. You pass in a 20 | JSON string, Emacs executes the specified function(s), and a JSON-RPC 2.0 21 | response is returned. 22 | 23 | This package is designed sit underneath a transport layer. No transport logic 24 | is included. The transport layer is responsible for communicating with 25 | external clients. Since JSON-RPC provides [no inbuilt 26 | mechanism](https://groups.google.com/d/msg/json-rpc/PN462g49yL8/DdMa93870_oJ) 27 | for authenticating requests, the transport layer should also handle 28 | authentication. 29 | 30 | The default transport layer is 31 | [Porthole](http://www.github.com/jcaw/porthole). It uses the HTTP 32 | protocol. 33 | 34 | 35 | --- 36 | 37 | 38 | 43 | 44 | ### Table of Contents 45 | 46 | - [How it Works](#how-it-works) 47 | - [Examples](#examples) 48 | - [Example: Calling a Method](#example-calling-a-method) 49 | - [Example: Invalid Request](#example-invalid-request) 50 | - [Example: Malformed JSON](#example-malformed-json) 51 | - [Example: Batch Requests](#example-batch-requests) 52 | - [Datatype Limitations](#datatype-limitations) 53 | - [Other Types](#other-types) 54 | - [Symbols](#symbols) 55 | - [Keyword Arguments](#keyword-arguments) 56 | - [Example: Symbols and Keyword Arguments](#example-symbols-and-keyword-arguments) 57 | - [Installation](#installation) 58 | - [List of Transport Layers](#list-of-transport-layers) 59 | - [FAQ](#faq) 60 | 61 | 62 | 63 | 64 | ## How it Works 65 | 66 | `json-rpc-server-handle` is the main entry point into the package (functions in this 67 | package are prefixed with `json-rpc-server-`). `json-rpc-server-handle` takes a JSON-RPC 2.0 [request 68 | string](https://www.jsonrpc.org/specification#request_object), and a list of 69 | functions that are allowed to be called remotely. 70 | 71 | ```emacs-lisp 72 | ;; This will decode a JSON-RPC 2.0 request, execute it, and return the JSON-RPC 2.0 response. 73 | (json-rpc-server-handle string-encoded-json-rpc-request 74 | list-of-legal-functions) 75 | ``` 76 | 77 | If successful, the result will be a string containing the JSON-RPC 2.0 [result 78 | response](https://www.jsonrpc.org/specification#response_object). If an error 79 | occurs, it will contain a JSON-RPC 2.0 [error 80 | response](https://www.jsonrpc.org/specification#error_object). Errors will be 81 | captured and encoded into strings - they won't be raised above the handler 82 | (unless you are debugging). 83 | 84 | Only functions you have specifically exposed can be called via RPC. You must 85 | pass a list of functions to `json-rpc-server-handle` so it knows which functions it's 86 | allowed to execute, and which it is not. 87 | 88 | ### Examples 89 | 90 | #### Example: Calling a Method 91 | 92 | Encode a request according to the JSON-RPC 2.0 protocol. `method` should be the 93 | method name, as a string. 94 | 95 | Here's an example request: 96 | 97 | ```json 98 | { 99 | "jsonrpc": "2.0", 100 | "method": "+", 101 | "params": [1, 2, 3], 102 | "id": 29492 103 | } 104 | ``` 105 | 106 | Let's encode this into a string and pass it to `json-rpc-server-handle`: 107 | 108 | ```emacs-lisp 109 | (json-rpc-server-handle 110 | "{ 111 | \"jsonrpc\": \"2.0\", 112 | \"method\": \"+\", 113 | \"params\": [1,2,3], 114 | \"id\": 29492 115 | }" 116 | ;; We have to make sure the `+' function is exposed to RPC calls. 117 | '(+)) 118 | ``` 119 | 120 | `json-rpc-server` will decode the request, then apply the function `+` to the 121 | list `'(1 2 3)`. Here's what the result of `json-rpc-server-handle` will be: 122 | 123 | ```emacs-lisp 124 | "{\"jsonrpc\":\"2.0\",\"result\":6,\"id\":29492}" 125 | ``` 126 | 127 | Decoded: 128 | 129 | ```json 130 | { 131 | "jsonrpc": "2.0", 132 | "result": 6, 133 | "id": 29492 134 | } 135 | ``` 136 | 137 | This string-encoded response can now be returned to the client. 138 | 139 | (See the [Symbols](#symbols) section for how to transfer symbols and keyword 140 | arguments.) 141 | 142 | #### Example: Invalid Request 143 | 144 | This time, let's try an invalid request. 145 | 146 | ```json 147 | { 148 | "params": [1, 2, 3], 149 | "id": 23092 150 | } 151 | ``` 152 | 153 | This request is invalid because it has no `"method"`. The call to `json-rpc-server-handle`: 154 | 155 | ```emacs-lisp 156 | (json-rpc-server-handle 157 | "{ 158 | \"params\": [1, 2, 3], 159 | \"id\": 23092 160 | }" 161 | '(+)) 162 | ``` 163 | 164 | Here's what `json-rpc-server-handle` returns: 165 | 166 | ```emacs-lisp 167 | "{\"jsonrpc\":\"2.0\",\"error\":{\"code\":-32600,\"message\":\"`method` was not provided.'\",\"data\":null},\"id\":23092}" 168 | ``` 169 | 170 | Decoded: 171 | 172 | ```json 173 | { 174 | "jsonrpc": "2.0", 175 | "error": { 176 | "code": -32600, 177 | "message": "`method` was not provided.", 178 | "data": null 179 | }, 180 | "id": 23092 181 | } 182 | ``` 183 | 184 | Note the `"id"` field. `json-rpc-server-handle` will do its best to extract an `id` from all 185 | requests, even invalid requests, so errors can be synced up to their respective 186 | requests. 187 | 188 | #### Example: Malformed JSON 189 | 190 | If there is a problem with the request (or another error occurs), `json-rpc-server-handle` 191 | will encode a JSON-RPC 2.0 [error 192 | response](https://www.jsonrpc.org/specification#error_object). Here's an 193 | example. 194 | 195 | Let's try some malformed JSON: 196 | 197 | ```json 198 | {Szx. dsd} 199 | ``` 200 | 201 | The call to `json-rpc-server-handle`: 202 | 203 | ```emacs-lisp 204 | (json-rpc-server-handle "{Szx. dsd}" '(+)) 205 | ``` 206 | 207 | Here's what `json-rpc-server-handle` returns: 208 | 209 | ```emacs-lisp 210 | "{\"jsonrpc\":\"2.0\",\"error\":{\"code\":-32700,\"message\":\"There was an error decoding the request's JSON.\",\"data\":{\"underlying-error\":{\"json-string-format\":[\"doesn't start with `\\\"'!\"]}}},\"id\":null}" 211 | ``` 212 | 213 | Decoded: 214 | 215 | ```json 216 | { 217 | "jsonrpc": "2.0", 218 | "error": { 219 | "code": -32700, 220 | "message": "There was an error decoding the request's JSON.", 221 | "data": { 222 | "underlying-error": { 223 | "type": "json-string-format", 224 | "data": ["doesn't start with `\"'!"] 225 | } 226 | } 227 | }, 228 | "id": null 229 | } 230 | ``` 231 | 232 | Note the `"data"` field. Some responses are triggered by an underlying error in 233 | the Elisp, which may contain more meaningful information about the error. When 234 | possible, that will be returned in the `"underlying-error"` field. If there is 235 | no underlying error, this field will not be present. 236 | 237 | #### Example: Batch Requests 238 | 239 | You can also execute multiple requests at once. This is useful if the client 240 | wants to minimize the number of requests they have to make to a slow transport 241 | layer. Each request will be executed, and a string response containing all the 242 | results will be returned. Unlike most JSON-RPC 2.0 protocols, batch requests are 243 | guaranteed to be executed in the same order they were received. 244 | 245 | Let's make two requests - one to a valid function, one to an invalid one. We'll 246 | batch them. 247 | 248 | ```json 249 | [ 250 | { 251 | "jsonrpc": "2.0", 252 | "method": "+", 253 | "params": [1, 2, 3], 254 | "id": 1 255 | }, 256 | { 257 | "jsonrpc": "2.0", 258 | "method": "insert", 259 | "params": ["Some text to insert"], 260 | "id": 2 261 | } 262 | ] 263 | ``` 264 | 265 | The call to `json-rpc-server-handle`: 266 | 267 | ```emacs-lisp 268 | (json-rpc-server-handle 269 | "[ 270 | { 271 | \"jsonrpc\": \"2.0\", 272 | \"method\": \"+\", 273 | \"params\": [1, 2, 3], 274 | \"id\": 1 275 | }, 276 | { 277 | \"jsonrpc\": \"2.0\", 278 | \"method\": \"insert\", 279 | \"params\": [\"Some text to insert\"], 280 | \"id\": 2 281 | } 282 | ]" 283 | ;; Let's expose `+', but not `insert', to demonstrate a result and an error. 284 | '(+)) 285 | ``` 286 | 287 | Here's what `json-rpc-server-handle` returns: 288 | 289 | ```emacs-lisp 290 | "[{\"jsonrpc\":\"2.0\",\"result\":6,\"id\":1},{\"jsonrpc\":\"2.0\",\"error\":{\"code\":-32601,\"message\":\"Function has not been exposed (it may or may not exist). Cannot execute.\",\"data\":null},\"id\":2}]" 291 | ``` 292 | 293 | Decoded: 294 | 295 | ```json 296 | [ 297 | { 298 | "jsonrpc": "2.0", 299 | "result": 6, 300 | "id": 1 301 | }, 302 | { 303 | "jsonrpc": "2.0", 304 | "error": { 305 | "code": -32601, 306 | "message": "Function has not been exposed (it may or may not exist). Cannot execute.", 307 | "data": null 308 | }, 309 | "id": 2 310 | } 311 | ] 312 | ``` 313 | 314 | As you can see, one of the function calls executed successfully, another caused 315 | an error. The responses should be returned in the same order their requests were 316 | submitted, but they can also be synchronized based on their `"id"`. 317 | 318 | `json-rpc-server-handle` assumes that requests are atomic until proven otherwise. If your 319 | batch request is *malformed*, `json-rpc-server-handle` will probably not return a batch in 320 | response - it will respond with a single "malformed json" error. 321 | 322 | ## Datatype Limitations 323 | 324 | The structure of JSON limits the types of variables that can be transferred. 325 | JSON only contains six datatypes. Thus, functions exposed by this protocol 326 | must expect certain datatypes. 327 | 328 | The datatypes are mapped as follows: 329 | 330 | | JSON Datatype | Decodeded Elisp Datatype | In JSON | In Elisp | 331 | | --- | --- | --- | --- | 332 | | string | string | `"string"` | `"string"` | 333 | | [quoted string](#symbols) | symbol | `"'symbol"`, `":keyword"` | `'symbol`, `:keyword` | 334 | | number | integer or float | `21`, `3.14` | `21`, `3.14` | 335 | | boolean | `t` or `:json-false` | `true`, `false` | `t`, `:json-false` | 336 | | null | `nil` | `null` | `nil` | 337 | | object | alist | `{"Key": "Value"}` | `'(("Key" . "Value"))'` | 338 | | array | list | `[1, 2, 4, 7]` | `'(1 2 4 7)` | 339 | 340 | Note that alist keys are decoded as strings. 341 | 342 | You may notice that "quoted strings" are decoded differently to normal strings. 343 | See the [Symbols](#symbols) section for a full explanation. 344 | 345 | ### Other Types 346 | 347 | Because of these type limitations, you cannot transfer vectors, plists, hash tables, 348 | cl-structs, etc. 349 | 350 | There is no easy way around this. JSON-RPC provides simplicity, at the cost of 351 | flexibility. If you want to call a function that expects a different type, you 352 | must write an intermediary function that translates from the available ones and 353 | publish your intermediary instead. 354 | 355 | ### Symbols 356 | 357 | Symbols are important in Elisp. Luckily, by abusing the JSON-RPC syntax we can 358 | transfer symbols. Strings beginning with a single quote will be decoded into 359 | symbols. Strings that start with a single colon will be decoded into keywords. 360 | 361 | For example: 362 | 363 | - The string `"'a-symbol"` becomes the symbol `'a-symbol`. 364 | - The string `":a-keyword"` becomes the symbol `:a-keyword`. 365 | - `"'wrapped-string'"` does not change, because it contains multiple quotes. It 366 | will stay a string. 367 | 368 | Let's send a list: 369 | 370 | ```json 371 | ["a string", "'a-symbol", ":a-keyword"] 372 | ``` 373 | 374 | That list will be decoded into: 375 | 376 | ```emacs-lisp 377 | '("a string" a-symbol :a-keyword) 378 | ``` 379 | 380 | ### Keyword Arguments 381 | 382 | By default, JSON-RPC 2.0 383 | [requires](https://www.jsonrpc.org/specification#parameter_structures) that 384 | keyword arguments be passed as "objects" (you might know them as dictionaries - 385 | `{"keyword": "value"}`). This is not supported. In Elisp, you cannot reference 386 | positional arguments by name and they may be mixed with keyword arguments. 387 | Objects aren't compatible with that structure. 388 | 389 | If you want to pass keyword arguments, you must encode them as a list: 390 | 391 | ```json 392 | { 393 | "params": ["positional-arg", 394 | ":keyword1", "value1", 395 | ":keyword2", "value2"] 396 | } 397 | ``` 398 | 399 | #### Example: Symbols and Keyword Arguments 400 | 401 | Here's an example of a request containing symbols and a keyword argument. Let's 402 | say we want Emacs to [flash the line](https://github.com/rolandwalker/nav-flash) 403 | after we scroll up, so we can keep track of the cursor. 404 | 405 | In Elisp, we could do something like this: 406 | 407 | ```emacs-lisp 408 | ;; Advise the `scroll-up' function to call `nav-flash-show' afterwards. 409 | (advice-add 'scroll-up :after 'nav-flash-show) 410 | ``` 411 | 412 | Here's how to encode that in a JSON-RPC call: 413 | 414 | ```json 415 | { 416 | "jsonrpc": "2.0", 417 | "method": "advice-add", 418 | "params": ["'scroll-up" ":after" "'nav-flash-show"], 419 | "id": 29492, 420 | } 421 | ``` 422 | 423 | This would be encoded into a string and passed to `json-rpc-server-handle`. It will decode a function call similar to the following: 424 | 425 | ```emacs-lisp 426 | (apply 427 | 'advice-add 428 | '(switch-to-buffer 429 | :after 430 | save-current-buffer)) 431 | ``` 432 | 433 | Expressed another way, this is equivalent to: 434 | 435 | ```emacs-lisp 436 | (advice-add 'switch-to-buffer :after 'save-current-buffer) 437 | ``` 438 | 439 | (Please note that this would be terrible way to flash the line in actual Emacs. 440 | Don't use it. You'd have to wait between each scroll press.) 441 | 442 | ## Installation 443 | 444 | The package itself is named `json-rpc-server`. It's easiest to install from MELPA. Make sure it's in your list of repositories, then: 445 | 446 | ```text 447 | M-x package-install RET json-rpc-server RET 448 | ``` 449 | 450 | Once installed, require it with: 451 | 452 | ```emacs-lisp 453 | (require 'json-rpc-server) 454 | ``` 455 | 456 | ## List of Transport Layers 457 | 458 | If you want to actually make RPC calls to Emacs, you need to use a transport 459 | layer. Here's a list: 460 | 461 | | Project | Protocol | 462 | | ------- | -------- | 463 | | [`Porthole`](http://www.github.com/jcaw/porthole) | HTTP | 464 | 465 | Have you written one? Open a pull request and I'll add it. 466 | 467 | ## FAQ 468 | 469 | - Is it compatible with older versions of JSON-RPC? 470 | 471 | Yes. It should work fine with older JSON-RPC requests. However, they aren't 472 | officially supported and the response will still be JSON-RPC 2.0. 473 | 474 | - Does it support keyword arguments? 475 | 476 | Yes, but not in the standard format. You may not pass them as objects. Pass 477 | them [as lists](#keyword-arguments), just like in Elisp. 478 | 479 | - How can I send a [vector, hash table, etc]? 480 | 481 | [You can't](#other-types). You have to write an intermediate function that constructs these 482 | types from alists, strings, etc. 483 | 484 | - Does it support notifications? 485 | 486 | No. All requests block until a value is returned (or an error occurs). This 487 | could be implemented at the transport level, if desired. 488 | 489 | - Does it support batch requests? 490 | 491 | Yes. See the [batch requests](#example-batch-requests) example. 492 | 493 | - Can I run multiple servers at once? 494 | 495 | `json-rpc-server` has a somewhat misleading name. It's not a server, it's a 496 | server-side implementation of the protocol. The transport layer can run as 497 | many servers as it likes. 498 | 499 | - Are you open to pull requests? 500 | 501 | Yes! Please pull against the 502 | [develop](https://github.com/jcaw/json-rpc-server.el/tree/develop) branch. 503 | -------------------------------------------------------------------------------- /test/json-rpc-server-test.el: -------------------------------------------------------------------------------- 1 | ;;; json-rpc-server-test.el --- Tests for json-rpc-server 2 | 3 | 4 | (require 'ert) 5 | 6 | (load-file "json-rpc-server.el") 7 | 8 | 9 | ;; Unit tests 10 | (progn 11 | ;; TODO: Find how to organize Elisp tests hierarchically. 12 | (ert-deftest test-json-rpc-server--validate-request () 13 | "Test for `json-rpc-server--validate-request'. 14 | 15 | Test whether it accepts good requests, and raises the 16 | correct errors for flawed requests. 17 | 18 | Note that when testing for raised errors, it doesn't test error 19 | messages - it just tests the class of the signal." 20 | ;; Valid request, all fields filled. 21 | ;; 22 | ;; We also use this test to ensure the request is returned. 23 | (let ((request '(("jsonrpc" . "2.0") 24 | ("method" . "message") 25 | ("params" . ("This is a %s" 26 | "test message")) 27 | ("id" . 12456)))) 28 | (should (equal (json-rpc-server--validate-request request) 29 | request))) 30 | ;; Valid request, but it's jsonrpc 1.0 31 | (should (json-rpc-server--validate-request 32 | '(("method" . "message") 33 | ("params" . ("This is a %s" 34 | "test message")) 35 | ("id" . 12456)))) 36 | ;; Valid request, but there's no params. 37 | (should (json-rpc-server--validate-request 38 | '(("jsonrpc" . "2.0") 39 | ("method" . "message") 40 | ("id" . 12456)))) 41 | 42 | ;; This time, the id is a string. 43 | (should (json-rpc-server--validate-request 44 | '(("jsonrpc" . "2.0") 45 | ("method" . "message") 46 | ("id" . "b48297ce-8e07-4e72-b487-4d06b45cdf52")))) 47 | 48 | ;; Invalid `jsonrpc' param 49 | (progn 50 | ;; jsonrpc is 3.0 - too high 51 | (should (catch 'json-rpc-server-respond 52 | (json-rpc-server--validate-request 53 | '(("jsonrpc" . "3.0") 54 | ("method" . "message") 55 | ("id" . 12456)))) 56 | ;; TODO: Type 57 | ) 58 | ;; jsonrpc is 2 - formatted wrong 59 | (should (catch 'json-rpc-server-respond 60 | (json-rpc-server--validate-request 61 | '(("jsonrpc" . "2") 62 | ("method" . "message") 63 | ("id" . 12456)))) 64 | ;; TODO: Type 65 | )) 66 | 67 | ;; Invalid `method' param 68 | (progn 69 | ;; No method 70 | (should (catch 'json-rpc-server-respond 71 | (json-rpc-server--validate-request 72 | '(("jsonrpc" . "2.0") 73 | ("id" . 12456)))) 74 | ;; TODO: Type 75 | ) 76 | ;; Wrong type for method 77 | (should (catch 'json-rpc-server-respond 78 | (json-rpc-server--validate-request 79 | '(("jsonrpc" . "2.0") 80 | ("method" . 120983) 81 | ("id" . 12456)))) 82 | ;; TODO: Type 83 | )) 84 | 85 | ;; Invalid `params' param 86 | (progn 87 | (should (catch 'json-rpc-server-respond 88 | (json-rpc-server--validate-request 89 | '(("jsonrpc" . "2.0") 90 | ("method" . "message") 91 | ("params" . "Just a string param") 92 | ("id" . 12456)))) 93 | ;; TODO: Type 94 | )) 95 | 96 | ;; Invalid `id' param 97 | (progn 98 | ;; No id 99 | (should (catch 'json-rpc-server-respond 100 | (json-rpc-server--validate-request 101 | '(("jsonrpc" . "2.0") 102 | ("method" . "message")))) 103 | ;; TODO: type 104 | ) 105 | ;; Invalid id type - in this case, a list. 106 | (should (catch 'json-rpc-server-respond 107 | (json-rpc-server--validate-request 108 | '(("jsonrpc" . "2.0") 109 | ("method" . "message") 110 | ("id" . ["this is a list"])))) 111 | ;; TODO: Type 112 | ) 113 | ;; Id is null. 114 | (should (catch 'json-rpc-server-respond 115 | (json-rpc-server--validate-request 116 | '(("jsonrpc" . "2.0") 117 | ("method" . "message") 118 | ("id" . :json-null)))) 119 | ;; TODO: Type 120 | )) 121 | ) 122 | 123 | (ert-deftest test-json-rpc-server--decode-request-json () 124 | "Test for `json-rpc-server--decode-request-json'. 125 | 126 | Test whether it decodes json correctly, in the way I want. 127 | 128 | Note that this does not test the functionality of `json.el'. It 129 | only tests the additional conditions imposed by the 130 | `json-rpc-server--decode-request-json' method." 131 | ;; List decoding 132 | (progn 133 | ;; Simple members 134 | (should (equal (json-rpc-server--decode-request-json 135 | "[1, 2, 3]") 136 | '(1 2 3))) 137 | (should (equal (json-rpc-server--decode-request-json 138 | "[\"first\", \"second\", \"third\"]") 139 | '("first" "second" "third")))) 140 | 141 | ;; Index and object decoding. 142 | ;; 143 | ;; Indexes should be strings, not symbols, and the result should be an 144 | ;; alist. 145 | (should (equal (json-rpc-server--decode-request-json 146 | "{\"index1\": \"value1\", \"index2\": \"value2\"}") 147 | '(("index1" . "value1") 148 | ("index2" . "value2")))) 149 | 150 | ;; Malformed json should raise a specific error, so it can be caught. 151 | (should (catch 'json-rpc-server-respond 152 | (json-rpc-server--decode-request-json 153 | ;; Some malformed JSON input. 154 | "als;d'asfoasf")) 155 | ;; TODO: Type (invalid json) 156 | ) 157 | 158 | ;; Try decoding a full request 159 | (should (equal 160 | (json-rpc-server--decode-request-json "{\"jsonrpc\": \"2.0\",\"method\": \"message\",\"params\": [\"This is a %s\", \"test message\"],\"id\": 12456,}") 161 | '(("jsonrpc" . "2.0") 162 | ("method" . "message") 163 | ("params" . ("This is a %s" 164 | "test message")) 165 | ("id" . 12456)))) 166 | ) 167 | 168 | (ert-deftest test-json-rpc-server--execute-request () 169 | "Test for `json-rpc-server--execute-request'. 170 | 171 | Note that this while this test does test a full function 172 | execution, it does not do so thoroughly. That is done in the unit 173 | test for the underlying function, 174 | `json-rpc-server--call-function'. 175 | 176 | This test is primarily designed to check that the function is 177 | correctly parsed and sent into `json-rpc-server--call-function'." 178 | (defun json-rpc-server--call-function-patch (func args) 179 | "Patched `json-rpc-server--call-function' that just checks 180 | the types of the arguments." 181 | (should (symbolp func)) 182 | ;; Note that nil counts as a list. 183 | (should (listp args))) 184 | 185 | ;; Mock `json-rpc-server--call-function' for these methods 186 | (cl-letf (((symbol-function 'json-rpc-server--call-function) 187 | 'json-rpc-server--call-function-patch)) 188 | ;; Check it executes okay with a simple method call 189 | (json-rpc-server--execute-request '(("method" . "message") 190 | ("params" . ("this is a %s message" 191 | "test")) 192 | ("id" . 1)) 193 | '(message)) 194 | ;; Check it executes okay no arguments 195 | (json-rpc-server--execute-request '(("method" . "message") 196 | ("id" . 1)) 197 | '(message))) 198 | 199 | ;; Ensure it executes correctly. 200 | (should (= (json-rpc-server--execute-request '(("method" . "+") 201 | ("params" . (1 2 3)) 202 | ("id" . 1)) 203 | '(+)) 204 | 6))) 205 | 206 | 207 | (ert-deftest test-json-rpc-server-internal-error-response () 208 | "Test for `json-rpc-server-internal-error-response'. 209 | 210 | Tests the correct JSON is constructed, and the correct errors raised." 211 | ;; Check a simple message. 212 | (should (cl-equalp (json-read-from-string 213 | (json-rpc-server-internal-error-response "This is a test")) 214 | '((jsonrpc . "2.0") 215 | (error . ((code . -32700) 216 | (message . "This is a test") 217 | (data . nil))) 218 | (id . nil)))) 219 | 220 | ;; Check a request that holds an id 221 | (should (cl-equalp (json-read-from-string 222 | (json-rpc-server-internal-error-response 223 | "This is a test" 224 | "{\"method\": \"message\",\"id\": 12456,}" 225 | )) 226 | '((jsonrpc . "2.0") 227 | (error . ((code . -32700) 228 | (message . "This is a test") 229 | (data . nil))) 230 | (id . 12456)))) 231 | 232 | ;; Check wrong message types 233 | (progn 234 | (should-error (json-rpc-server-internal-error-response nil) 235 | :type 'error) 236 | (should-error (json-rpc-server-internal-error-response 1) 237 | :type 'error) 238 | (should-error (json-rpc-server-internal-error-response '(("an" . "alist"))) 239 | :type 'error)) 240 | 241 | ;; Check wrong JSON types 242 | ;; 243 | ;; These forms should execute without issue, but they should NOT contain an 244 | ;; id. 245 | (progn 246 | ;; nil JSON 247 | (should (not 248 | (alist-get 249 | 'id 250 | (json-read-from-string 251 | (json-rpc-server-internal-error-response "This is a test" nil))))) 252 | ;; Wrong JSON structure 253 | (should (not 254 | (alist-get 255 | 'id 256 | (json-read-from-string 257 | (json-rpc-server-internal-error-response "This is a test" "12980"))))) 258 | ;; Non-string JSON 259 | (should (not 260 | (alist-get 261 | 'id 262 | (json-read-from-string 263 | (json-rpc-server-internal-error-response "This is a test" 12980)))))) 264 | ) 265 | 266 | (ert-deftest test-json-rpc-server--decode-id () 267 | "Test for `json-rpc-server--decode-id'. 268 | 269 | Tests that it decodes the id in minimalistic JSON, and also that 270 | it does not block with errors when it cannot decode the id." 271 | ;; It should extract the id even if the overall request is invalid. 272 | (should (eq (json-rpc-server--decode-id "{\"id\": 10249}") 273 | 10249)) 274 | ;; Also check strings 275 | (should (equal (json-rpc-server--decode-id "{\"id\": \"10249\"}") 276 | "10249")) 277 | 278 | ;; These are all invalid JSON, so they should return nil. Nothing should 279 | ;; raise an error. 280 | (progn 281 | ;; Null id 282 | (should (eq (json-rpc-server--decode-id "{\"id\": null}") 283 | nil)) 284 | ;; Invalid id type: object (dictionary) 285 | (should (eq (json-rpc-server--decode-id "{\"id\": {\"nested\": \"dict\"}}") 286 | nil))) 287 | ) 288 | 289 | (ert-deftest test-json-rpc-server--replace-symbol-strings () 290 | "Test for `test-json-rpc-server--replace-symbol-strings'. 291 | 292 | This test throws hypothetical objects at 293 | `test-json-rpc-server--replace-symbol-strings' and ensures it 294 | replaces the symbols correctly." 295 | ;; Symbol variants - cover normal symbols, and keywords. 296 | (progn 297 | (should (eq (json-rpc-server--replace-symbol-strings "'symbol") 298 | 'symbol)) 299 | (should (eq (json-rpc-server--replace-symbol-strings "'SYMBOL") 300 | 'SYMBOL)) 301 | (should (eq (json-rpc-server--replace-symbol-strings ":keyword") 302 | :keyword)) 303 | (should (eq (json-rpc-server--replace-symbol-strings ":KEYWORD") 304 | :KEYWORD)) 305 | 306 | ;; Special case - quoted keywords should just parse like normal symbols 307 | (should (eq (json-rpc-server--replace-symbol-strings "':keyword") 308 | :keyword))) 309 | 310 | ;; Straight strings 311 | (progn 312 | (should (equal (json-rpc-server--replace-symbol-strings "a string") 313 | "a string")) 314 | (should (equal (json-rpc-server--replace-symbol-strings "'double quoted string'") 315 | "'double quoted string'")) 316 | (should (equal (json-rpc-server--replace-symbol-strings ":double key string:") 317 | ":double key string:"))) 318 | 319 | ;; There's no special handling for keywords with apostrophes in. 320 | (should (equal (json-rpc-server--replace-symbol-strings ":mixed 'keyword") 321 | :mixed\ \'keyword)) 322 | 323 | ;; Other types 324 | (progn 325 | (should (eq (json-rpc-server--replace-symbol-strings nil) 326 | nil)) 327 | (should (eq (json-rpc-server--replace-symbol-strings 23) 328 | 23))) 329 | 330 | ;; Nested types 331 | (should (equal (json-rpc-server--replace-symbol-strings '(something)) 332 | '(something))) 333 | (should (equal (json-rpc-server--replace-symbol-strings '(nil)) 334 | '(nil))) 335 | (should (equal (json-rpc-server--replace-symbol-strings '("string")) 336 | '("string"))) 337 | (should (equal (json-rpc-server--replace-symbol-strings '("'symbol")) 338 | '(symbol))) 339 | 340 | ;; Cons cells 341 | (should (equal (json-rpc-server--replace-symbol-strings '("'symbol" . "a string")) 342 | '(symbol . "a string"))) 343 | 344 | ;; Monster nesting test - test this thoroughly 345 | (should (equal (json-rpc-server--replace-symbol-strings 346 | '( 347 | ;; Cons cell 348 | ("string1" . "'symbol1") 349 | ;; Straight list 350 | ("string2" "'symbol2" ":keyword2" 2) 351 | ;; Individual components 352 | ":keyword3" 353 | "'symbol3" 354 | "string3" 355 | 3 356 | ("string4" 357 | ;; Nested cons cell 358 | ("'symbol4" . ":keyword4") 359 | 4))) 360 | '( 361 | ;; Cons cell 362 | ("string1" . symbol1) 363 | ;; Straight list 364 | ("string2" symbol2 :keyword2 2) 365 | ;; Individual components 366 | :keyword3 367 | symbol3 368 | "string3" 369 | 3 370 | ("string4" 371 | ;; Nested cons cell 372 | (symbol4 . :keyword4) 373 | 4)))) 374 | ) 375 | ) 376 | 377 | 378 | ;; Integration tests 379 | (progn 380 | ;; None yet. 381 | 382 | (ert-deftest test-full-procedure-call--to-+ () 383 | "Test a valid procedure call to `+'. 384 | 385 | Note that `+' is a command that doesn't change the editor's 386 | state. Thus this checks a limited type of functionality." 387 | ;; Get the response first, then progressively check each part of its 388 | ;; contents. 389 | (let ((response (json-read-from-string 390 | (json-rpc-server-handle 391 | (json-encode 392 | '(("jsonrpc" . "2.0") 393 | ("method" . "+") 394 | ("params" . [1 2 3]) 395 | ("id" . 21145))) 396 | '(+))))) 397 | ;; Check each component, *then* check the full structure. We do this to 398 | ;; make it easier to pinpoint why the test is failing. 399 | (should (equal (alist-get 'jsonrpc response) 400 | "2.0")) 401 | (should (eq (alist-get 'result response) 402 | 6)) 403 | ;; The JSON-RPC 2.0 specification indicates that, on a successful 404 | ;; response, the `error' parameter should not be present in the response 405 | ;; at all. It cannot simply be null - it should not be there. 406 | (should (eq (assoc 'error response) 407 | nil)) 408 | (should (eq (alist-get 'id response) 409 | 21145)) 410 | ;; Since Elisp has no reliable way of comparing alists with the same 411 | ;; elements in different orders, this is sensitive to the *order* of the 412 | ;; JSON object returned. The test will fail if the order changes. Not 413 | ;; perfect. 414 | (should (cl-equalp response 415 | '((jsonrpc . "2.0") 416 | (result . 6) 417 | (id . 21145))))) 418 | ) 419 | 420 | (ert-deftest test-full-procedure-call--changing-internal-state () 421 | "Test a valid procedure call that just changes a variable. 422 | 423 | This test is designed to test an internal state change. It tests 424 | relatively minimal stay changing functionality. Only a variable 425 | is changed - things like the buffer should be unaffected." 426 | ;; We have to define a function to change the variable, that takes a string 427 | ;; name as input, since we can't transfer symbols via JSON. 428 | (defun json-rpc-server-custom-setq (var-name new-value) 429 | (set (intern var-name) new-value)) 430 | (let ( 431 | ;; This is the variable we will try to change 432 | (test-var 10298) 433 | ) 434 | (json-rpc-server-handle 435 | (json-encode 436 | '(("jsonrpc" . "2.0") 437 | ("method" . "json-rpc-server-custom-setq") 438 | ("params" . ["test-var" "this is a test string"]) 439 | ("id" . 21145))) 440 | '(json-rpc-server-custom-setq)) 441 | (should (string= test-var 442 | "this is a test string")))) 443 | 444 | (ert-deftest test-full-procedure-call--changing-buffer () 445 | "Test a valid procedure call to `insert', with a temp buffer. 446 | 447 | This test is designed to test functionality that changes the 448 | state of the buffer. 449 | 450 | This only tests the change in the buffer - other tests are 451 | responsible for checking the actual response of the API." 452 | ;; Temporarily expose `insert' 453 | (with-temp-buffer 454 | (json-rpc-server-handle 455 | (json-encode 456 | '(("jsonrpc" . "2.0") 457 | ("method" . "insert") 458 | ("params" . ["this is a test string"]) 459 | ("id" . 21145))) 460 | '(insert)) 461 | (should (string= (buffer-string) 462 | "this is a test string"))) 463 | ) 464 | 465 | (ert-deftest test-full-procedure-call--unexposed-function () 466 | "Test a procedure call to a function that hasn't been exposed. 467 | 468 | This test is designed to test two things: 469 | 470 | 1. The error type of a function that has not been exposed. This 471 | should match the JSON-RPC 2.0 specification. Specifically, 472 | the error code needs to match. 473 | 474 | 2. The structure of an error response. 475 | 476 | Other integration tests will check other error codes, but they 477 | won't check the structure of the response. It is assumed that 478 | this test is sufficient to check that for other error codes." 479 | ;; Get the response first, then progressively check each part of its 480 | ;; contents. 481 | (let* ((response (json-read-from-string 482 | (json-rpc-server-handle 483 | (json-encode 484 | '(("jsonrpc" . "2.0") 485 | ("method" . "+") 486 | ("params" . [1 2 3]) 487 | ("id" . 21145))) 488 | ;; Expose no functions 489 | '()))) 490 | (response-error (alist-get 'error response))) 491 | (should response) 492 | ;; Check each component, *then* check the full structure. We do this to 493 | ;; make it easier to pinpoint why the test is failing. 494 | (should (equal (alist-get 'jsonrpc response) 495 | "2.0")) 496 | ;; The JSON-RPC 2.0 specification indicates that, when an error is 497 | ;; raised, the `result' parameter should not be present in the response 498 | ;; at all. It cannot simply be null - it should not be there. 499 | (should (eq (assoc 'result response) 500 | nil)) 501 | (should (eq (alist-get 'id response) 502 | 21145)) 503 | (should (eq (alist-get 'code response-error) 504 | ;; This error code corresponds to "method not found" in the 505 | ;; JSON-RPC 2.0 specification. 506 | -32601)) 507 | (should (eq (alist-get 'data response-error) 508 | nil)) 509 | ;; We don't check the exact string 510 | (should (stringp (alist-get 'message response-error))))) 511 | 512 | (ert-deftest test-full-procedure-call--non-existant-function () 513 | "Test a procedure call to a function that has been exposed, but doesn't exist. 514 | 515 | This test is designed to trick the system up by making it think 516 | it is calling a valid function, causing an unexpected error when 517 | the function is invoked." 518 | (let* ((response (json-read-from-string 519 | (json-rpc-server-handle 520 | (json-encode 521 | '(("method" . "json-rpc-server-function-that-does-not-exist") 522 | ("id" . 1))) 523 | '(json-rpc-server-function-that-does-not-exist)))) 524 | (response-error (alist-get 'error response))) 525 | (should response) 526 | ;; We only check the response code 527 | (should (eq (alist-get 'code response-error) 528 | ;; This error code corresponds to "method not found" in the 529 | ;; JSON-RPC 2.0 specification. 530 | -32601)))) 531 | 532 | (ert-deftest test-full-procedure-call--empty-json () 533 | "Test a procedure call with empty JSON." 534 | (let* ((response (json-read-from-string 535 | ;; The exposed functions don't matter here. Just pass an 536 | ;; empty list. 537 | (json-rpc-server-handle "{}" '()))) 538 | (response-error (alist-get 'error response))) 539 | (should response) 540 | (should (eq (alist-get 'code response-error) 541 | ;; This error code corresponds to "invalid request" in the 542 | ;; JSON-RPC 2.0 specification. 543 | -32600)))) 544 | 545 | (ert-deftest test-full-procedure-call--with-symbols () 546 | "Test a valid procedure call, that includes symbols. 547 | 548 | Symbols have to be passed by abusing the JSON syntax. Test a full 549 | procedure call works using this paradigm." 550 | ;; Temporarily expose `insert' 551 | (cl-defun json-rpc-server--symbols-test-function (arg1 &key keyword) 552 | ;; Keyword should be passed as a keyword, arg2 should end up a symbol. 553 | (should (equal arg1 "string")) 554 | (should (eq keyword 'symbol)) 555 | t) 556 | (should (json-rpc-server-handle 557 | (json-encode 558 | '(("jsonrpc" . "2.0") 559 | ("method" . "json-rpc-server--symbols-test-function") 560 | ("params" . ["string" ":keyword" "'symbol"]) 561 | ("id" . 201398))) 562 | '(json-rpc-server--symbols-test-function))) 563 | ) 564 | 565 | (ert-deftest test-full-procedure-call--quoted-method () 566 | "Test that a procedure call still works when the function is quoted. 567 | 568 | Given the way symbols are encoded, the user may get confused. 569 | They might pass the function name quoted, rather than as a 570 | straight string. This should be tolerated." 571 | (let ((response (json-read-from-string 572 | (json-rpc-server-handle 573 | (json-encode 574 | '(("jsonrpc" . "2.0") 575 | ("method" . "'+") 576 | ("params" . [1 2 3]) 577 | ("id" . 23234))) 578 | '(+))))) 579 | (should-not (alist-get 'error response)) 580 | (should (eq (alist-get 'result response) 581 | 6)) 582 | (should (cl-equalp response 583 | '((jsonrpc . "2.0") 584 | (result . 6) 585 | (id . 23234))))) 586 | ) 587 | ) 588 | 589 | 590 | ;;; json-rpc-server-test.el ends here 591 | -------------------------------------------------------------------------------- /json-rpc-server.el: -------------------------------------------------------------------------------- 1 | ;;; json-rpc-server.el --- Server-side JSON-RPC library. -*- lexical-binding: t; -*- 2 | 3 | ;; Copyright (C) 2019 GitHub user "Jcaw" 4 | 5 | ;; Author: GitHub user "Jcaw" 6 | ;; URL: https://github.com/jcaw/json-rpc-server.el 7 | ;; Keywords: tools, comm, json, rpc 8 | ;; Version: 0.3.0 9 | ;; Package-Requires: ((emacs "26")) 10 | 11 | ;; This program is free software; you can redistribute it and/or modify 12 | ;; it under the terms of the GNU General Public License as published by 13 | ;; the Free Software Foundation, either version 3 of the License, or 14 | ;; (at your option) any later version. 15 | 16 | ;; This program is distributed in the hope that it will be useful, 17 | ;; but WITHOUT ANY WARRANTY; without even the implied warranty of 18 | ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 19 | ;; GNU General Public License for more details. 20 | 21 | ;; You should have received a copy of the GNU General Public License 22 | ;; along with this program. If not, see . 23 | 24 | ;;; Commentary: 25 | 26 | ;; This is a full implementation of the JSON-RPC 2.0 protocol[1] for Emacs. You 27 | ;; pass in a JSON string, Emacs executes the specified function(s), and a 28 | ;; JSON-RPC 2.0 response is returned. 29 | 30 | ;; It was originally part of Porthole, a full-fledged HTTP-based RPC server for 31 | ;; Emacs: 32 | 33 | ;; http://www.github.com/jcaw/porthole 34 | 35 | ;; The underlying JSON-RPC protocol was extracted into a separate package so 36 | ;; that it could serve as a framework on which other RPC servers could be built. 37 | 38 | ;; *No transport logic is included.* This package is designed to sit underneath 39 | ;; a transport layer, which is responsible for communicate with external 40 | ;; clients. Since JSON-RPC provides no inbuilt mechanism for authenticating 41 | ;; requests, the transport layer should also handle authentication. 42 | 43 | ;; Here's en example request: 44 | 45 | ;; { 46 | ;; "jsonrpc": "2.0", 47 | ;; "method": "insert", 48 | ;; "params": ["some text to insert"], 49 | ;; "id": "3140983184" 50 | ;; } 51 | 52 | ;; Pass this as a string to `json-rpc-server-handle' - the specified text will 53 | ;; be inserted and the return value of the call to `insert' will be encoded into 54 | ;; a response. 55 | 56 | ;; Symbols and keywords can be passed by abusing the JSON-RPC syntax as follows: 57 | 58 | ;; { 59 | ;; "a symbol": "'a-symbol", 60 | ;; "a keyword": ":a-keyword" 61 | ;; } 62 | 63 | ;; This is a simplified explanation of the package that glosses over a lot of 64 | ;; details. Please refer to the full README[3] for an up-to-date and thorough 65 | ;; explanation. 66 | 67 | ;; [1] https://www.jsonrpc.org/specification 68 | 69 | ;; [2] https://groups.google.com/d/msg/json-rpc/PN462g49yL8/DdMa93870_o 70 | 71 | ;; [3] http://www.github.com/jcaw/json-rpc-server.el/README.md 72 | 73 | 74 | ;;; Code: 75 | 76 | 77 | (require 'json) 78 | (require 'cl-lib) 79 | 80 | 81 | (defgroup json-rpc-server nil 82 | "Group relating to json-rpc-server.el" 83 | :prefix "json-rpc-server-" 84 | :link `(url-link :tag "Send Bug Report" 85 | "https://github.com/jcaw/json-rpc-server.el/issues") 86 | :link '(url-link :tag "Other Emacs packages by Jcaw" 87 | "https://github.com/jcaw?utf8=%E2%9C%93&tab=repositories&q=&type=source&language=emacs+lisp") 88 | :link '(url-link :tag "Homepage" 89 | "https://github.com/jcaw/json-rpc-server.el") 90 | :group 'tools) 91 | 92 | 93 | (defvar json-rpc-server--error-codes 94 | '((json-rpc-server-invalid-request-json . -32700) 95 | (json-rpc-server-invalid-request . -32600) 96 | (json-rpc-server-invalid-function . -32601) 97 | (json-rpc-server-invalid-params . -32602) 98 | (json-rpc-server-error-calling-method . -32603)) 99 | "Alist mapping procedural errors to their JSON-RPC 2.0 error codes.") 100 | 101 | 102 | (defvar json-rpc-server--unknown-error-code -32603 103 | "Error code to be used for unknown errors.") 104 | 105 | 106 | (defun json-rpc-server--convert-for-json (data) 107 | "Recursively convert `DATA' to make it compatible with `json-serialize'. 108 | 109 | Alists are converted into hash tables, and regular lists 110 | converted into vectors. The objective is to make the output of 111 | `json-serialize' match that of `json-encode'." 112 | (cond ((stringp data) data) 113 | ((listp data) 114 | (if (json-alist-p data) 115 | (let ((data-as-table (make-hash-table :size (length data)))) 116 | (mapc (lambda (pair) 117 | (puthash (if (symbolp (car pair)) 118 | (symbol-name (car pair)) 119 | (car pair)) 120 | (json-rpc-server--convert-for-json (cdr pair)) 121 | data-as-table)) 122 | data) 123 | data-as-table) 124 | (vconcat (mapcar 'json-rpc-server--convert-for-json data)))) 125 | ((hash-table-p data) 126 | (maphash (lambda (key value) 127 | (let ((new-key (if (symbolp key) 128 | (progn 129 | (remhash key data) 130 | (symbol-name key)) 131 | key))) 132 | (puthash new-key 133 | (json-rpc-server--convert-for-json value) 134 | data))) 135 | data) 136 | data) 137 | ;; Don't want to convert these to a string. 138 | ((member data `(t nil :json-false)) data) 139 | ((symbolp data) (symbol-name data)) 140 | (t data))) 141 | 142 | 143 | (defconst json-rpc-server--use-native-serialize 144 | (and (fboundp 'json-serialize) 145 | (>= emacs-major-version 27)) 146 | "Use Emacs 27+'s native C JSON serialization?") 147 | 148 | 149 | (defun json-rpc-server--emulate-legacy-encode (data) 150 | "Emulate the behaviour of `json-encode', using fast encoding when possible. 151 | 152 | Emacs 27 introduces native C serialization for JSON, but it 153 | doesn't behave the same way as `json-encode'. It's stricter in 154 | the datatypes it requires. 155 | 156 | To get around this, we can convert the native elisp objects 157 | before encoding, so the output matches that of `json-encode' but 158 | the encoding process is a lot faster (~50x faster, even with the 159 | overhead of conversion)." 160 | (if (and json-rpc-server--use-native-serialize 161 | ;; New `json-serialize' doesn't seem to work with basic types. 162 | (not (member data '(nil t))) 163 | (not (stringp data)) 164 | (not (numberp data)) 165 | (not (symbolp data))) 166 | (json-serialize (json-rpc-server--convert-for-json data) 167 | :null-object nil 168 | :false-object :json-false) 169 | (json-encode data))) 170 | 171 | 172 | (defun json-rpc-server--get-error-code (error-symbol) 173 | "Get the JSON-RPC 2.0 specification error code for an error. 174 | 175 | `ERROR-SYMBOL' should be a symbol representing the error." 176 | (interactive) 177 | (or (alist-get error-symbol json-rpc-server--error-codes) 178 | json-rpc-server--unknown-error-code)) 179 | 180 | 181 | (defun json-rpc-server--construct-error-response (error-code 182 | message 183 | &optional 184 | underlying-error) 185 | "Encode a JSON-RPC 2.0 error response. 186 | 187 | The result will be a JSON-RPC 2.0 response string, containing 188 | information about the error. For example: 189 | 190 | `((\"jsonrpc\" . \"2.0\") 191 | (\"error\" . ((code . -32600) 192 | (message . \"This is an error.\") 193 | (data . [...])))) 194 | 195 | This method does not include an `id' in the response. The id must 196 | be added before this response is actually returned. 197 | 198 | Arguments: 199 | 200 | `ERROR-CODE' - The error code to respond with. 201 | 202 | `MESSAGE' - The message to send. 203 | 204 | `UNDERLYING-ERROR' - Optional. You may wish to add an underlying 205 | Elisp error to the response, for example if there was a problem 206 | executing the supplied method. Pass it here and it will be 207 | encoded and attached. Default: nil" 208 | (let* ( 209 | ;; The additional data should be an alist of additional data keys to 210 | ;; their data. 211 | ;; 212 | ;; Additional data should *only* have a value when additional data exists. 213 | ;; It should be null otherwise. 214 | (additional-data nil)) 215 | (when underlying-error 216 | (setq additional-data 217 | (append 218 | additional-data 219 | `((underlying-error . ((type . ,(car underlying-error)) 220 | ;; The data should be a list, since it's a 221 | ;; `cdr'. Encode as much of it as we can. 222 | (data . ,(mapcar 'json-rpc-server--replace-unencodable-object 223 | (cdr underlying-error))))))))) 224 | ;; The id will be added later. 225 | `(("jsonrpc" . "2.0") 226 | ("error" . ((code . ,error-code) 227 | (message . ,message) 228 | (data . ,additional-data)))))) 229 | 230 | 231 | (cl-defun json-rpc-server--throw-error-response (error-code message &key (original-error nil)) 232 | "Throw a `json-rpc-server-respond' signal with an error response attached. 233 | 234 | `MESSAGE' - the error message to attach. 235 | 236 | `:ORIGINAL-ERROR' - Optional. The original error that was thrown. 237 | Information about this error will be sent back in the 238 | response." 239 | (throw 'json-rpc-server-respond 240 | (json-rpc-server--construct-error-response error-code message original-error))) 241 | 242 | 243 | (cl-defun json-rpc-server--throw-invalid-json (message &key (original-error nil)) 244 | "Throw a `json-rpc-server-response' with a \"malformed JSON\" error code. 245 | 246 | `MESSAGE' - the error message to attach. 247 | 248 | `:ORIGINAL-ERROR' - Optional. The original error that was thrown. 249 | Information about this error will be sent back in the 250 | response." 251 | (json-rpc-server--throw-error-response 252 | (json-rpc-server--get-error-code 'json-rpc-server-invalid-request-json) 253 | message 254 | :original-error original-error)) 255 | 256 | 257 | (defun json-rpc-server--throw-invalid-request (message) 258 | "Throw a `json-rpc-server-response' with an \"invalid request\" error code. 259 | 260 | `MESSAGE' is the error message to attach." 261 | (json-rpc-server--throw-error-response 262 | (json-rpc-server--get-error-code 'json-rpc-server-invalid-request) 263 | message)) 264 | 265 | 266 | (defun json-rpc-server--throw-invalid-function (message) 267 | "Throw a `json-rpc-server-response' with an \"invalid function\" error code. 268 | 269 | `MESSAGE' is the error message to attach." 270 | (json-rpc-server--throw-error-response 271 | (json-rpc-server--get-error-code 'json-rpc-server-invalid-function) 272 | message)) 273 | 274 | 275 | (cl-defun json-rpc-server--throw-error-calling-method (message &key original-error) 276 | "Throw a `json-rpc-server-response' with an \"internal error\" error code. 277 | 278 | `MESSAGE' is the error message to attach. 279 | 280 | `:ORIGINAL-ERROR' - The original error that was thrown. 281 | Information about this error will be sent back in the 282 | response." 283 | (json-rpc-server--throw-error-response 284 | (json-rpc-server--get-error-code 'json-rpc-server-error-calling-method) 285 | message 286 | :original-error original-error)) 287 | 288 | 289 | (defun json-rpc-server--throw-result (result) 290 | "Throw a `json-rpc-server-response' with a successful result attached. 291 | 292 | `RESULT' should be the raw result of the method execution." 293 | (throw 'json-rpc-server-respond (json-rpc-server--construct-result-response result))) 294 | 295 | 296 | (defun json-rpc-server--construct-result-response (result) 297 | "Create a JSON-RPC 2.0 response with a successful result. 298 | 299 | `RESULT' should be the raw result data returned by the procedure 300 | invoked. 301 | 302 | Example output: 303 | 304 | '((\"jsonrpc\" . \"2.0\") 305 | (\"result\" . 6)) 306 | 307 | This method does not attach an \"id\" to the response. The id 308 | should be added before this response is returned to a client." 309 | ;; TODO: Handle errors encoding the result. If that happens, the response 310 | ;; should be a new JSON-RPC error defined by this API to indicate that the 311 | ;; response could not be encoded. 312 | ;; 313 | ;; The id will be added later 314 | `(("jsonrpc" . "2.0") 315 | ("result" . ,result))) 316 | 317 | 318 | ;; -------------------------------------------------------------------------- 319 | 320 | 321 | (defun json-rpc-server-null-p (value) 322 | "Is `VALUE' either nil, or json-null? 323 | 324 | Other falsey values, such as 0, do not count. Note that the empty 325 | list is equivalent to nil, so the empty list counts as nil." 326 | ;; TODO: Only allow `nil' here, for parity with `json-serialize'? 327 | (or (eq value nil) 328 | (eq value json-null))) 329 | 330 | 331 | (defun json-rpc-server-alist-get (key alist) 332 | "Like `alist-get', but works with string keys. 333 | 334 | `KEY' is the key to query. 335 | `ALIST' is the alist to search." 336 | (let ((pair (assoc key alist))) 337 | (and pair 338 | (eq (type-of pair) 'cons) 339 | (cdr pair)))) 340 | 341 | 342 | (defun json-rpc-server--call-function-internal (func args) 343 | "Apply `FUNC' to `ARGS'. 344 | 345 | This wrapper is abstracted from `json-rpc-server--call-function' 346 | to make it easier for developers to debug function calls 347 | themselves, without worrying about broader behavior." 348 | (apply func args)) 349 | 350 | 351 | (defun json-rpc-server--call-function (func args) 352 | "Execute the remote procedure call for `FUNC' with `ARGS'." 353 | ;; TODO: Allow macro calls here too? 354 | (condition-case err 355 | (json-rpc-server--call-function-internal func args) 356 | (error 357 | (json-rpc-server--throw-error-calling-method 358 | "There was an error calling the method." 359 | :original-error err)))) 360 | 361 | 362 | (defun json-rpc-server--execute-request (request exposed-functions) 363 | "Execute a remote procedure call. 364 | 365 | `REQUEST' should be an alist representing a JSON-RPC 2.0 request. 366 | 367 | `EXPOSED-FUNCTIONS' should be a list of function symbols that are 368 | allowed to be executed. The method will not be executed unless 369 | it's in this list. See `json-rpc-server-handle' for more details. 370 | 371 | An error will be raised if the function in the request does not 372 | exist (or has not been exposed.)" 373 | (let* ((method-name (json-rpc-server-alist-get "method" request)) 374 | ;; Because we can only transport strings via JSON, the method name has 375 | ;; to be encoded as a string. That means we have to manually convert it 376 | ;; into a symbol before invocation. 377 | (method-symbol 378 | ;; If the method-name was quoted, it will already have been converted 379 | ;; to a symbol. 380 | (if (symbolp method-name) 381 | method-name 382 | ;; I don't know what kind of strings fail to convert to symbols, but 383 | ;; add error handling just in case. 384 | (condition-case nil 385 | (intern method-name) 386 | (error 387 | (json-rpc-server--throw-invalid-request 388 | (concat 389 | "`method` could not be converted to an Elisp symbol. It " 390 | "should be a string that converts into an elisp symbol.")))))) 391 | (args (json-rpc-server-alist-get "params" request))) 392 | ;; We now check that the function is legal, and callable, before trying to 393 | ;; call it. 394 | (unless (member method-symbol exposed-functions) 395 | (json-rpc-server--throw-invalid-function 396 | (concat 397 | "Function has not been exposed (it may or may not exist). Cannot " 398 | "execute."))) 399 | (unless (functionp method-symbol) 400 | (json-rpc-server--throw-invalid-function 401 | "This symbol has been exposed, but it is not a function. Cannot call it.")) 402 | ;; TODO: Check if function is callable with args. Can the function signature 403 | ;; be checked in Elisp? 404 | (json-rpc-server--call-function method-symbol args))) 405 | 406 | 407 | (defun json-rpc-server--validate-request (request-alist) 408 | "Validate that a decoded request has the correct structure. 409 | 410 | The request should be provided in the form of an alist, in 411 | `REQUEST-ALIST'. 412 | 413 | If the request is invalid, an error response signal will be 414 | thrown. Ensure these signals are caught." 415 | (when (json-rpc-server-null-p request-alist) 416 | (json-rpc-server--throw-invalid-request "No request provided")) 417 | (unless (json-alist-p request-alist) 418 | (json-rpc-server--throw-invalid-request "The request was not a JSON \"object\"")) 419 | (let* ((jsonrpc (json-rpc-server-alist-get "jsonrpc" request-alist)) 420 | (method (json-rpc-server-alist-get "method" request-alist)) 421 | (params (json-rpc-server-alist-get "params" request-alist)) 422 | (id (json-rpc-server-alist-get "id" request-alist)) 423 | ;; If there's no `jsonrpc' parameter, we assume this is probably a 424 | ;; jsonrpc 1.0 request. 425 | (appears-to-be-jsonrpc-v1 (json-rpc-server-null-p jsonrpc)) 426 | ;; It's jsonrpc 2.0 iff the jsonrpc string is "2.0" *exactly*. 427 | (is-jsonrpc-v2.0 (and (stringp jsonrpc) 428 | (string= jsonrpc "2.0")))) 429 | ;; The supported jsonrpc versions are 2.0 and lower. Other versions are not 430 | ;; supported. 431 | (unless (or is-jsonrpc-v2.0 432 | appears-to-be-jsonrpc-v1) 433 | (json-rpc-server--throw-invalid-request 434 | (concat "Only jsonrpc versions 1 to 2.0 are supported. jsonrpc 2.0 is " 435 | "preferred. If the `jsonrpc` parameter is included, it must be " 436 | "\"2.0\" exactly."))) 437 | (unless method 438 | (json-rpc-server--throw-invalid-request "`method` was not provided.")) 439 | ;; TODO: Perhaps ensure the function is not a `json-rpc-server' function? 440 | ;; E.g. disallow the `json-rpc-server-' prefix? Perhaps not. Unlikely to be reliable. 441 | ;; User should simply never expose those functions. 442 | (unless (or (stringp method) 443 | ;; Sometimes users may get confused and send a symbol as the 444 | ;; method name. That's fine. Tolerate this behavior. 445 | (symbolp method)) 446 | (json-rpc-server--throw-invalid-request "`method` should be a string.")) 447 | ;; `params' should be a list of arguments, but it is optional. We have to 448 | ;; allow a nil value. 449 | (unless (or (json-rpc-server-null-p params) 450 | (listp params)) 451 | ;; TODO: Should this be a JSON-RPC "invalid params" error? 452 | (json-rpc-server--throw-invalid-request 453 | (concat "`params` was provided, but it was not an array. Could " 454 | "not decode the parameters into a list."))) 455 | (unless id 456 | (json-rpc-server--throw-invalid-request "`id` not provided")) 457 | ;; "id" can be a string or a number. Floats are allowed, which seems odd 458 | ;; given the potential for rounding errors. 459 | (unless (or (numberp id) 460 | (stringp id)) 461 | (json-rpc-server--throw-invalid-request "`id` should be an integer.")) 462 | request-alist)) 463 | 464 | 465 | (defun json-rpc-server--decode-request-json (json) 466 | "Decode JSON with custom rules and error handling. 467 | 468 | Arrays will be decoded into lists, objects (dictionaries) will be 469 | decoded into alists, and keys will be decoded into symbols. 470 | 471 | If there is an error parsing the JSON, a response will be thrown 472 | indicating that the request had invalid json. Ensure this 473 | response is caught." 474 | ;; Decode symbol-like strings into symbols. Do this as part of the JSON 475 | ;; parsing process. 476 | (json-rpc-server--replace-symbol-strings 477 | ;; Set some custom options for the JSON decoder. 478 | (let ( 479 | ;; Arrays should be decoded as lists, because this is the array-like 480 | ;; type most methods are going to expect. 481 | ;; 482 | ;; This adds a limitation to the RPC server. Some functions may expect 483 | ;; vectors, but only one type of list can be transferred via JSON. Those 484 | ;; functions will receive lists. This will have to be fixed manually by 485 | ;; the user with some kind of proxy function. 486 | (json-array-type 'list) 487 | ;; Hash tables are faster, but alists are more common. 488 | (json-object-type 'alist) 489 | ;; Keys should be symbols because alists keys should generally be 490 | ;; symbols, not strings. 491 | (json-key-type 'string) 492 | ) 493 | (condition-case err 494 | ;; Reading JSON with the legacy system is much faster than writing it, 495 | ;; so we're still using it for now. 496 | ;; 497 | ;; TODO: Switch JSON reading to Emacs 27 primitives 498 | (json-read-from-string json) 499 | (error 500 | ;; Catch JSON errors and raise a json-rpc-server error that can be more easily 501 | ;; understood. 502 | (json-rpc-server--throw-invalid-json 503 | "There was an error decoding the request's JSON." 504 | :original-error err)))))) 505 | 506 | 507 | (defun json-rpc-server--replace-symbol-strings (object) 508 | "Replace symbol-like strings with symbols. 509 | 510 | `OBJECT' is the decoded JSON object you want to modify. It should 511 | be composed of only the basic JSON types, decoded into Elisp. 512 | 513 | This is a hack that allows symbols (most importantly, keyword 514 | arguments) to be sent over the JSON-RPC protocol. It takes 515 | strings prefixed with a single \"'\" or \":\", and converts them 516 | into symbols. For example: 517 | 518 | \"'some-name\" -> 'some-name 519 | 520 | \":KEYWORD\" -> :KEYWORD 521 | 522 | Strings with more than one quote/colon won't be converted. For 523 | example: 524 | 525 | \"'a quote'\" -> \"'a quote'\" 526 | 527 | This method replaces the symbols inline in the request structure. 528 | The structure itself will be modified. 529 | 530 | This is a recursive function. It will call itself. Ensure 531 | `max-lisp-eval-depth' is high enough to parse your JSON object." 532 | (cond ((stringp object) 533 | (cond ((string-match "^:[^:]+$" object) 534 | ;; If there's an error interning the object, just pass back the 535 | ;; original string. 536 | (condition-case nil 537 | (intern object) 538 | (error object))) 539 | ((string-match "^'[^']+$" object) 540 | ;; If there's an error interning the object, just pass back the 541 | ;; original string. 542 | (condition-case nil 543 | ;; If it's prefixed with a quote, we have to shave off the quote 544 | ;; before interning. 545 | (intern (substring object 1)) 546 | (error object))) 547 | ;; It wasn't a symbol. Return the original string. 548 | (t object))) 549 | ((consp object) 550 | (cons (json-rpc-server--replace-symbol-strings (car object)) 551 | (json-rpc-server--replace-symbol-strings (cdr object)))) 552 | (t object))) 553 | 554 | 555 | (defun json-rpc-server--replace-unencodable-object (object) 556 | "Replace `OBJECT' if it can't be encoded into JSON. 557 | 558 | This function is designed to sanitise complex objects before they 559 | are encoded. 560 | 561 | Method: 562 | 563 | 1. This function attempts to encode `OBJECT' into JSON. 564 | 565 | 2a. If it works, that's fine - the original `OBJECT' is 566 | returned, unaltered. 567 | 568 | 2b. If it can't be encoded, that's a problem. A string is 569 | returned instead, indicating that the object could not be 570 | encoded properly. 571 | 572 | Usage example: 573 | 574 | Let's say an error was raised during method execution, and 575 | we're trying it. This shouldn't be a problem, but an error can 576 | theoretically contain any kind of data. There is a (very small) 577 | risk that the error will contain data that can't be encoded, 578 | crashing the JSON serializer. 579 | 580 | We can call this method on the data in the error to protect 581 | ourselves. If some part can't be encoded, it will simply be 582 | replaced with a message for the end user indicating the 583 | problem." 584 | ;; TODO: Replace only the lowest-level objects, if possible. Would have to 585 | ;; make this function recursive to do that. 586 | (condition-case nil 587 | (progn 588 | (json-rpc-server--emulate-legacy-encode object) 589 | object) 590 | (error 591 | (format 592 | (concat "[Object of type %s could not be encoded into JSON. " 593 | "This string was inserted instead.]") 594 | (type-of object))))) 595 | 596 | 597 | (defun json-rpc-server--extract-id (decoded-request) 598 | "Attempt to extract a valid ID from a request alist and NOTHING ELSE. 599 | 600 | If no valid ID could be extracted, returns nil. Valid IDs are 601 | numbers and strings. 602 | 603 | This method will not raise errors. 604 | 605 | `DECODED-REQUEST' should be a JSON-RPC request (up to 2.0), 606 | decoded from JSON into an alist form." 607 | (ignore-errors 608 | (let ((id (json-rpc-server-alist-get "id" decoded-request))) 609 | (when (or (stringp id) 610 | (integerp id)) 611 | id)))) 612 | 613 | 614 | (defun json-rpc-server--decode-id (request-in-json) 615 | "Attempt to decode a valid id from a JSON request and NOTHING ELSE. 616 | 617 | If no valid id could be decoded, returns nil. 618 | 619 | This method will not raise errors. 620 | 621 | `REQUEST-IN-JSON' should be a JSON-RPC request (up to 2.0) in 622 | JSON form." 623 | (ignore-errors 624 | (json-rpc-server--extract-id (json-rpc-server--decode-request-json request-in-json)))) 625 | 626 | 627 | (defun json-rpc-server-unknown-error-response (&optional request-in-json) 628 | "Construct a JSON response indicating an unknown error. 629 | 630 | This is a utility method for the transport layer to use when it 631 | wishes to send a JSON-RPC 2.0 error without knowing any details. 632 | 633 | If possible, please supply this method with the original JSON-RPC 634 | request, as a JSON string, in `REQUEST-IN-JSON'. It will be used 635 | by this method to extract as much information as possible for the 636 | response." 637 | (json-rpc-server-internal-error-response "An unknown error occurred" 638 | request-in-json)) 639 | 640 | 641 | (defun json-rpc-server-internal-error-response (message &optional request-in-json) 642 | "Construct a JSON response indicating internal error `MESSAGE'. 643 | 644 | This is a utility method for the transport layer to use to 645 | generate a valid JSON-RPC 2.0 response related to an arbitrary 646 | internal error. For example, if there is an internal error in the 647 | transport layer, this could be used to wrap the error into a 648 | valid JSON-RPC 2.0 response. 649 | 650 | If possible, please supply this method with the original JSON-RPC 651 | request, as a JSON string, in `REQUEST-IN-JSON'. It will be used 652 | by this method to extract as much information as possible for the 653 | response." 654 | ;; We manually construct the JSON from a string to minimise the chance of an 655 | ;; unexpected error, or a strange encoding of the JSON. 656 | 657 | ;; Ensure `MESSAGE' is a string to ensure it encodes predictably (i.e. as a 658 | ;; string). 659 | (unless (stringp message) 660 | (error "%s" "`message' must be a string")) 661 | (let ((id (or (json-rpc-server--decode-id request-in-json) 662 | "null"))) 663 | (format 664 | " 665 | { 666 | \"jsonrpc\": \"2.0\", 667 | \"error\": { 668 | \"code\": -32700, 669 | \"message\": %s, 670 | \"data\": null 671 | }, 672 | \"id\": %s 673 | }" 674 | ;; We encode the message explicitly to prevent something being injected 675 | ;; into the JSON. 676 | (json-rpc-server--emulate-legacy-encode message) 677 | id))) 678 | 679 | 680 | (defun json-rpc-server--ammend-id (id response) 681 | "Add an \"id\" to a JSON-RPC response. 682 | 683 | `ID' should be the id. `RESPONSE' should be the raw response, 684 | before it's encoded into a string." 685 | (append response `((id . ,id)))) 686 | 687 | 688 | (defun json-rpc-server--handle-single (decoded-request exposed-functions) 689 | "Handle a single JSON-RPC request. 690 | 691 | `DECODED-REQUEST' should be a JSON-RPC (up to 2.0) request, 692 | decoded into an alist. 693 | 694 | `EXPOSED-FUNCTIONS' should be a list of function symbols that are 695 | allowed to be executed. The method will not be executed unless 696 | it's in this list. See `json-rpc-server-handle' for more details. 697 | 698 | Returns the JSON-RPC response, encoded in JSON." 699 | (let ( 700 | ;; We attempt to decode the id using a robust method, to give us the 701 | ;; maximum chance of being able to include it in the response if there is 702 | ;; an error. 703 | ;; 704 | ;; This may still fail - that's OK. We just want to maximize the chance 705 | ;; of extracting it. 706 | (id (json-rpc-server--extract-id decoded-request))) 707 | (json-rpc-server--ammend-id 708 | id 709 | (catch 'json-rpc-server-respond 710 | (json-rpc-server--construct-result-response 711 | (json-rpc-server--execute-request 712 | (json-rpc-server--validate-request decoded-request) 713 | exposed-functions)))))) 714 | 715 | 716 | (defun json-rpc-server-handle (request-in-json exposed-functions) 717 | "Handle a JSON-RPC request. 718 | 719 | Parameters 720 | ---------- 721 | 722 | `REQUEST-IN-JSON' should be a JSON-RPC (up to 2.0) request, 723 | encoded in a JSON string. 724 | 725 | `EXPOSED-FUNCTIONS' should be a list of function symbols that are 726 | exposed to RPC calls. The RPC call will only be executed if its 727 | method is in this list. 728 | 729 | - Each function name should be a symbol. 730 | 731 | - Do not include raw functions such as lambdas. 732 | 733 | - Do not include string names. 734 | 735 | Returns the JSON-RPC 2.0 response, encoded in a JSON string. 736 | 737 | Description 738 | ----------- 739 | 740 | This is the main entry point into the RPC layer. This is the 741 | method that decodes the RPC request and executes it. This method 742 | is transport-agnostic - transport has to be implemented 743 | separately. 744 | 745 | This method can take either a single encoded request, or an 746 | encoded list of requests, per the JSON-RPC 2.0 specification. 747 | 748 | Please note that this implementation deviates slightly from the 749 | JSON-RPC 2.0 specification: 750 | 751 | 1. Notifications are not supported. All RPC requests will 752 | receive a response. Notifications may be implemented above 753 | this layer, at the transport level. 754 | 755 | 2. Batch requests are not processed concurrently. Batch 756 | requests will always be processed in the order they are 757 | supplied. Responses will be supplied in the same order." 758 | (json-rpc-server--emulate-legacy-encode 759 | (catch 'json-rpc-server-respond 760 | ;; Per JSON-RPC 2.0 specification, requests can either be single requests or 761 | ;; a list of requests. Each type has to be handled differently, so we decode 762 | ;; it up-front. 763 | (let* ((decoded-request (json-rpc-server--decode-request-json request-in-json)) 764 | ;; Because JSON objects (i.e. dictionaries) will be decoded into 765 | ;; alists, we can't just assume lists are batch requests. Single 766 | ;; requests will also look like lists. Instead, ensure the request is 767 | ;; a list *and* not a dictionary. 768 | (is-batch-request (and 769 | ;; If the request is an empty list (or null), we 770 | ;; can't iterate over it. We have to process it 771 | ;; as a single request. 772 | (not (json-rpc-server-null-p decoded-request)) 773 | (listp decoded-request) 774 | (not (json-alist-p decoded-request))))) 775 | (if is-batch-request 776 | ;; Process each request in turn; Return all the results, in a list. 777 | (mapcar (lambda (request) 778 | "Handle a single request from the batch" 779 | (json-rpc-server--handle-single request exposed-functions)) 780 | decoded-request) 781 | (json-rpc-server--handle-single decoded-request exposed-functions)))))) 782 | 783 | 784 | (provide 'json-rpc-server) 785 | ;;; json-rpc-server.el ends here 786 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | GNU GENERAL PUBLIC LICENSE 2 | Version 3, 29 June 2007 3 | 4 | Copyright (C) 2007 Free Software Foundation, Inc. 5 | Everyone is permitted to copy and distribute verbatim copies 6 | of this license document, but changing it is not allowed. 7 | 8 | Preamble 9 | 10 | The GNU General Public License is a free, copyleft license for 11 | software and other kinds of works. 12 | 13 | The licenses for most software and other practical works are designed 14 | to take away your freedom to share and change the works. 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Interpretation of Sections 15 and 16. 613 | 614 | If the disclaimer of warranty and limitation of liability provided 615 | above cannot be given local legal effect according to their terms, 616 | reviewing courts shall apply local law that most closely approximates 617 | an absolute waiver of all civil liability in connection with the 618 | Program, unless a warranty or assumption of liability accompanies a 619 | copy of the Program in return for a fee. 620 | 621 | END OF TERMS AND CONDITIONS 622 | 623 | How to Apply These Terms to Your New Programs 624 | 625 | If you develop a new program, and you want it to be of the greatest 626 | possible use to the public, the best way to achieve this is to make it 627 | free software which everyone can redistribute and change under these terms. 628 | 629 | To do so, attach the following notices to the program. It is safest 630 | to attach them to the start of each source file to most effectively 631 | state the exclusion of warranty; and each file should have at least 632 | the "copyright" line and a pointer to where the full notice is found. 633 | 634 | 635 | Copyright (C) 636 | 637 | This program is free software: you can redistribute it and/or modify 638 | it under the terms of the GNU General Public License as published by 639 | the Free Software Foundation, either version 3 of the License, or 640 | (at your option) any later version. 641 | 642 | This program is distributed in the hope that it will be useful, 643 | but WITHOUT ANY WARRANTY; without even the implied warranty of 644 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 645 | GNU General Public License for more details. 646 | 647 | You should have received a copy of the GNU General Public License 648 | along with this program. If not, see . 649 | 650 | Also add information on how to contact you by electronic and paper mail. 651 | 652 | If the program does terminal interaction, make it output a short 653 | notice like this when it starts in an interactive mode: 654 | 655 | Copyright (C) 656 | This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. 657 | This is free software, and you are welcome to redistribute it 658 | under certain conditions; type `show c' for details. 659 | 660 | The hypothetical commands `show w' and `show c' should show the appropriate 661 | parts of the General Public License. Of course, your program's commands 662 | might be different; for a GUI interface, you would use an "about box". 663 | 664 | You should also get your employer (if you work as a programmer) or school, 665 | if any, to sign a "copyright disclaimer" for the program, if necessary. 666 | For more information on this, and how to apply and follow the GNU GPL, see 667 | . 668 | 669 | The GNU General Public License does not permit incorporating your program 670 | into proprietary programs. If your program is a subroutine library, you 671 | may consider it more useful to permit linking proprietary applications with 672 | the library. If this is what you want to do, use the GNU Lesser General 673 | Public License instead of this License. But first, please read 674 | . 675 | --------------------------------------------------------------------------------