Jobe-compatible API

Set up CodeRunner

1. Get a free API key at your dashboard.
2. In Moodle, open Site administration > Plugins > Question types > CodeRunner.
3. Set Jobe server to https://api.onlinecompiler.io/api, with the https:// (without it, CodeRunner uses http).
4. Set Jobe API key to your API key, save, and check an answer in any CodeRunner question.

The key goes in X-API-KEY, as CodeRunner sends it. Requests and responses keep Jobe's shape, and errors come back as a JSON string.

curl -X POST https://api.onlinecompiler.io/api/jobe/index.php/restapi/runs \
  -H "X-API-KEY: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "run_spec": {
      "language_id": "python3",
      "sourcecode": "print(input()[::-1])",
      "input": "hello\n",
      "parameters": { "cputime": 3 }
    }
  }'

Response (200)

{
  "run_id": null,
  "outcome": 15,
  "cmpinfo": "",
  "stdout": "olleh\n",
  "stderr": ""
}

Language ids

Jobe's own ids, which CodeRunner's built-in question types use, run on these compilers. A custom question type can name any of the other 38 ids as its sandbox language.

Also: ada (Ada), bash (Bash), clojure (Clojure), cobol (COBOL), crystal (Crystal), csharp (C#), d (D), dart (Dart), duckdb (DuckDB), elixir (Elixir), erlang (Erlang), fortran (Fortran), freebasic (FreeBASIC), fsharp (F#), go (Go), groovy (Groovy), haskell (Haskell), julia (Julia), kotlin (Kotlin), lisp (Common Lisp), lua (Lua), nasm (Assembly), nim (Nim), objectivec (Objective-C), ocaml (OCaml), perl (Perl), powershell (PowerShell), prolog (Prolog), r (R), racket (Racket), ruby (Ruby), rust (Rust), scala (Scala), sqlite (SQL), swift (Swift), typescript (TypeScript), vbnet (Visual Basic), zig (Zig).

Outcomes and errors

• 15 the program ran and exited cleanly; 11 compile error, with the compiler's messages in cmpinfo, which includes a syntax error in Python, Java or PHP as on Jobe; 12 runtime error (a non-zero exit or a signal); 13 time limit; 17 memory limit; 19 more than 16 processes at once, which CodeRunner shows as an illegal function call; 30 output over 64 KB; 20 an internal error on our side.
• 21 (overload): your plan's per-minute, pending or at-once limit was reached, or the sandboxes were busy. Nothing ran and nothing was counted; the same run can be sent again shortly.
• HTTP 401: the monthly allowance of your account or key is spent, which CodeRunner reports as a submission limit. 403: the key is missing, unknown or not a REST API key. 404: a file in file_list isn't stored, so CodeRunner uploads it and sends the run again. 400: a bad request, with the reason.

Differences from Jobe

• Every run is a fresh gVisor sandbox with no network access and our limits: 512 MB of memory and at most 16 processes.
• parameters.cputime stops the run, 5 seconds when it is absent as on Jobe, capped at 30 seconds. Compiling does not count, and Java (1 s), Groovy (1.5 s) and F# (2.5 s) get a start-up allowance on top. memorylimit, numprocs, streamsize and disklimit are accepted and ignored.
• compileargs, linkargs and interpreterargs are ignored: programs compile with our commands. C compiles in GCC 15's default dialect rather than Jobe's -std=c99, and without -Werror. Compiler warnings arrive in stderr, and CodeRunner marks any stderr as an error, so warnings still fail an answer as they would on Jobe.
• runargs are refused with a 400: programs get no command-line arguments.
• sourcefilename is ignored. A Java file takes its public class's name, so CodeRunner's Java templates, which put the student's class before the test harness, run as on Jobe.
• Each language runs in a sandbox of its own, so a template that calls another language's compiler from Python does not work: the Python sandbox has no gcc, javac or php. That includes CodeRunner's built-in multilanguage question type, which compiles the student's chosen language from a Python template.
• A run's files follow the input file limits: up to 8 files and 1 MB, with plain names. Uploaded files are kept per account, up to the 200 most recently used and 50 MB.
• Each run counts as one run toward your monthly allowance. Listing languages and uploading or checking files are free.

Why use a hosted Jobe? See CodeRunner without a Jobe server.