JSON Schema implementation in Erlang and standalone validation server.

• Basic server logic
• Basic validation logic
• Constraints
• Schema builder
• Schema validation

• Put your schemas in webroot directory. May use subdirectories too. (Great tool for generating JSON schema from JSON)
• Start server (it listens on port 5000 by default, can be changed in etc/app.config)
• GET request will receive schema from server. Possible responses:
• HTTP 200 OK (schema in response body)
• HTTP 404 Schema not found
• HTTP 500 Broken schema
• POST request will validate JSON sent as request body. Possible responses:
• HTTP 200 OK (JSON validates against schema)
• HTTP 404 Schema not found
• HTTP 460 Invalid input (input is not a valid JSON)
• HTTP 461 Invalid JSON (JSON does not validates against schema)
• HTTP 500 Broken schema Response will contain JSON-encoded array of validation errors or empty array if validation passes.

Let's assume that webroot directory has following structure:

webroot
 |-- schemas_v1
 |    |-- schema1.jsonschema
 |    +-- schema2.jsonschema
 |
 +-- schemas_v2
      |-- schema1.jsonschema
      +-- schema2.jsonschema

• Request GET localhost:5000/schemas_v1/schema1.jsonschema will receive webroot/schemas_v1/schema1.jsonschema
• Request POST localhost:5000/schemas_v1/schema1.jsonschema will validate posted JSON against schema in webroot/schemas_v1/schema1.jsonschema file and return validation errors in response.

You may use JSON Validator as library. Required sources are jvalidator_validator.erl and all constraint_*.erl files. To perform validation you need to decode your JSON and JSON schema by mochijson2:decode/1 function and pass them to jvalidator_validator:validate/2 function.

Json2 = mochijson2:decode(Json),
Schema2 = mochijson2:decode(Schema),
ValidationErrors = jvalidator_validator:validate(Json2, Schema2).

• Mochiweb