RESTful API

There‘s a simple restful API that can be used to do compiles to asm and to list compilers. In general all handlers live in /api/* endpoints, will accept JSON or text in POSTs, and will return text or JSON responses depending on the request’s Accept header.

At a later date there may be some form of rate-limiting: currently, requests will be queued and dealt with in the same way interactive requests are done for the main site. Authentication might be required at some point in the future (for the main Compiler Explorer site anyway).

Endpoints

GET /api/languages - return a list of languages

Returns a list of the currently supported languages, as pairs of languages IDs and their names.

GET /api/compilers - return a list of compilers

Returns a list of compilers. In text form, there's a simple formatting of the ID of the compiler, its description and its language ID. In JSON, all the information is returned as an array of compilers, with the id key being the primary identifier of each compiler.

Due to the amount of compilers and information available through this api call, by default you will only get these fields per compiler: ['id', 'name', 'lang', 'compilerType', 'semver', 'extensions', 'monaco']

If you require different fields, you can specify them by adding ?fields=field1,field2,field3 to your query.

To see all the available fields, you can use ?fields=all. It is not recommended using this by default.

GET /api/compilers/<language-id> - return a list of compilers with matching language

Returns a list of compilers for the provided language id. In text form, there's a simple formatting of the ID of the compiler, its description and its language ID. In JSON, all the information is returned as an array of compilers, with the id key being the primary identifier of each compiler.

The same field restrictions apply as with GET /api/compilers

GET /api/libraries/<language-id> - return a list of libraries available with for a language

Returns a list of libraries and library versions available for the provided language id. This request only returns data in JSON.

You can use the given include paths to supply in the userArguments for compilation. (deprecated)

You will need the library id‘s, and the version id’s to supply to compile if you want to include libraries during compilation.

GET /api/shortlinkinfo/<linkid> - return information about a given link

Returns information like Sourcecode, Compiler settings and libraries for a given link id. This request only returns data in JSON.

POST /api/compiler/<compiler-id>/compile - perform a compilation

To specify a compilation request as a JSON document, post it as the appropriate type and send an object of the form:

{
    "source": "<Source-to-compile>",
    "options": {
        "userArguments": "<Compiler-flags>",
        "compilerOptions": {
              "skipAsm": false,
              "executorRequest": false
        },
        "filters": {
             "binary": false,
             "binaryObject": false,
             "commentOnly": true,
             "demangle": true,
             "directives": true,
             "execute": false,
             "intel": true,
             "labels": true,
             "libraryCode": false,
             "trim": false
        },
        "tools": [
             {"id":"clangtidytrunk", "args":"-checks=*"}
        ],
        "libraries": [
             {"id": "range-v3", "version": "trunk"},
             {"id": "fmt", "version": "400"}
        ]
    },
    "lang": "<lang-id (Optional)>",
    "allowStoreCodeDebug": true
}

Execution Only request example:

{
    "source": "int main () { return 1; }",
    "compiler": "g82",
    "options": {
        "userArguments": "-O3",
        "executeParameters": {
            "args": ["arg1", "arg2"],
            "stdin": "hello, world!"
        },
        "compilerOptions": {
            "executorRequest": true
        },
        "filters": {
            "execute": true
        },
        "tools": [],
        "libraries": [
            {"id": "openssl", "version": "111c"}
        ]
    },
    "lang": "c++",
    "allowStoreCodeDebug": true
}

The filters are a JSON object with true/false values. If not supplied, defaults are used. If supplied, the provided filters override their default values. The compilerOptions is used to pass extra arguments to the back end, and is probably not useful for most REST users.

To force a cache bypass, set bypassCache in the root of the request to true.

Filters include binary, binaryObject, labels, intel, directives and demangle, which correspond to the UI buttons on the HTML version.

With the tools array you can ask CE to execute certain tools available for the current compiler, and also supply arguments for this tool.

Libraries can be marked to have their directories available when including their header files. The can be listed by supplying the library ids and versions in an array. The id's to supply can be found with the /api/libraries/<language-id>

Note that using external header files of the type:

#include <https://some-url.to/a-file.h>

is not supported for this endpoint for security reasons.

The feature for the site is handled client-side, as the compilation nodes have no internet access.

GET /api/formats - return available code formatters

Returns a list of code formatters. The API returns an array of formatter objects which have the following object structure:

{
    "exe": "/opt/compiler-explorer/rustfmt-1.4.36/rustfmt",
    "version": "rustfmt 1.4.36-nightly (7de6968 2021-02-07)",
    "name": "rustfmt",
    "styles": [],
    "type": "rustfmt"
}

The name property corresponds to the <formatter> when requesting POST /api/format/<formatter>. The type key in the JSON request corresponds to one of the formatters.<key>.type found in https://github.com/compiler-explorer/compiler-explorer/blob/main/etc/config/compiler-explorer.amazon.properties#L43

POST /api/format/<formatter> - perform a formatter run

Formats a piece of code according to the given base style using the provided formatter

Formatters available can be found with GET /api/formats

{
    "source": "int main(     ) {}",
    "base": "Google",
    "useSpaces": false,
    "tabWidth": 4
}

The returned JSON body has the following object structure:

{
    "answer": "int main() {}",
    "exit": 0
}

In cases of internal code formatter failure an additional field named throw is also provided and set to true.

Non-REST API's

POST /api/compiler/<compiler-id>/compile - perform a compilation

This is same endpoint as for compilation using JSON.

A text compilation request has the source as the body of the post, and uses query parameters to pass the options and filters. Filters are supplied as a comma-separated string. Use the query parameter filters=XX to set the filters directly, else addFilters=XX to add a filter to defaults, or removeFilters to remove from defaults. Compiler parameters should be passed as options=-O2 and default to empty.

The text request is designed for simplicity for command-line clients like curl

$ curl 'https://godbolt.org/api/compiler/g63/compile?options=-Wall' --data-binary 'int foo() { return 1; }'
# Compilation provided by Compiler Explorer at godbolt.org
foo():
        push    rbp
        mov     rbp, rsp
        mov     eax, 1
        pop     rbp
        ret

If JSON is present in the request's Accept header, the compilation results are of the form:

(Optional values are marked with a **)

{
  "code": 0 if successful, else compiler return code,
  "stdout": [
            {
              "text": Output,
              ** "tag": {
                          "line": Source line,
                          "text": Parsed error for that line
                 }
            },
            ...
  ],
  "stderr": (format is similar to that of stdout),
  "asm": [
         {
           "text": Assembly text,
           "source": {file: null for user input, else path, line: number} or null if none
         },
         ...
  ],
  "tools": [],
  "okToCache": true if output could be locally cached else false,
  ** "optOutput" : {
                     "displayString" : String displayed in output,
                     "Pass" : [ Missed | Passed | Analysis ] (Specifies the type of optimisation output),
                     "Name" : Name of the output (mostly represents the reason for the output),
                     "DebugLoc" : {
                        "File": Name of file,
                        "Line": Line number,
                        "Column": Column number in line
                     },
                     "Function": Name of function for which optimisation output is provided,
                     "Args": Array of objects representing the arguments that the optimiser used when trying to optimise
     }
}

POST /api/shortener - saves given state forever to a shortlink and returns the unique id for the link

The body of this post should be in the format of a ClientState Be sure that the Content-Type of your post is application/json

An example of one the easiest forms of a clientstate:

{
  "sessions": [
    {
      "id": 1,
      "language": "c++",
      "source": "int main() { return 42; }",
      "compilers": [
        {
          "id": "g82",
          "options": "-O3"
        }
      ],
      "executors": [
        {
          "arguments": "arg1",
          "compiler": {
              "id": "g92",
              "libs": [],
              "options": "-O3"
          },
          "stdin": ""
        }
      ]
    }
  ]
}

Returns:

{
    "url": "https://godbolt.org/z/Km_340"
}

The storedId can be used in the api call /api/shortlinkinfo/ and to open in the website with a /z/ shortlink.

GET /z/<id> - Opens the website from a shortlink

This call opens the website in a state that was previously saved using the built-in shortener.

GET /z/<id>/code/<sourceid> - Returns just the sourcecode from a shortlink

This call returns plain/text for the code that was previously saved using the built-in shortener.

If there were multiple editors during the saved session, you can retrieve them by setting to 1, 2, 3, etcetera, otherwise can be set to 1.

GET /clientstate/<base64> - Opens the website in a given state

This call is to open the website with a given state (without having to store the state first with /api/shortener) Instead of sending the ClientState JSON in the post body, it will have to be encoded with base64 and attached directly onto the URL.

To avoid problems in reading base64 by the API, some characters must be kept in unicode. Therefore, before calling the API, it is necessary to replace these characters with their respective unicodes. A suggestion is to use the Regex expression /[\u007F-\uFFFF]/g that allows mapping these characters.

Implementations

Here are some examples of projects using the Compiler Explorer API: