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Schema parser for Protobuf compatible with AsyncAPI JS Parser

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asyncapi/protobuf-schema-parser

ProtoBuff Data Types Schema Parser

A schema parser for Protocol Buffers data types. For ProtoBuff 2 and 3 schemas.

There is no explicit distinction between ProtoBuff 2 and 3. You dont have to expect any errors if your schemaFormat is application/vnd.google.protobuf;version=2 defined, but your schema is proto3.

Version >= 2.0.0 of package is only supported by @asyncapi/parser version >= 2.0.0.

This package is browser-compatible.

Installation

npm install @asyncapi/protobuf-schema-parser
// OR
yarn add @asyncapi/protobuf-schema-parser

Usage

import {Parser} from '@asyncapi/parser';
import {ProtoSchemaParser} from '@asyncapi/protobuf-schema-parser'

const parser = new Parser();
parser.registerSchemaParser(ProtoSchemaParser());

const asyncapiWithProto = `
asyncapi: 2.0.0
info:
  title: Example with ProtoBuff
  version: 0.1.0
channels:
  example:
    publish:
      message:
        schemaFormat: 'application/vnd.google.protobuf;version=3'
        payload: |
            message Point {
                required int32 x = 1;
                required int32 y = 2;
                optional string label = 3;
            }

            message Line {
                required Point start = 1;
                required Point end = 2;
                optional string label = 3;
            }
`

const {document} = await parser.parse(asyncapiWithProto);
const {Parser} = require('@asyncapi/parser');
const {ProtoSchemaParser} = require('@asyncapi/protobuf-schema-parser');

const parser = new Parser();
parser.registerSchemaParser(ProtoSchemaParser());

const asyncapiWithProto = `
asyncapi: 2.0.0
info:
  title: Example with ProtoBuff
  version: 0.1.0
channels:
  example:
    publish:
      message:
        schemaFormat: 'application/vnd.google.protobuf;version=3'
        payload: |
            message Point {
                required int32 x = 1;
                required int32 y = 2;
                optional string label = 3;
            }

            message Line {
                required Point start = 1;
                required Point end = 2;
                optional string label = 3;
            }
`

const {document} = await parser.parse(asyncapiWithProto);

Place your protoBuff schema as string in payload to get it parsed.

References are NOT supported:

  • no support for $ref
  • no support for import, except the default google types:
    • google/protobuf/*
    • google/type/*

Comments

Each field of a message may have a comment witch will be reflected as json schema description. Furthermore, the comment can contain the following annotations:

message Point {
    /*
     * The cordinate on the x axis.
     * @Default 99
     * @Min 0
     * @Max 100 
     */
    required int32 x = 1;
    
    /*
     * The cordinate on the y axis.
     * @Default 12
     * @Min 0
     * @Max 100 
     */
    required int32 y = 2;
    optional string label = 3;
}

Per field annotation

annotation description
@Example json schema examples keyword. Can exists multiple times. If used with an complex type, an single lines json object hast to be used.
@Min or @Minimum json schema numeric validator
@Max or @Maximum json schema numeric validator
@Pattern json scheme string validator
@ExclusiveMinimum json schema numeric validator
@ExclusiveMaximum json schema numeric validator
@MultipleOf json schema numeric validator
@MinLength json scheme string validator
@MaxLength json scheme string validator
@MinItems json scheme array validator
@MaxItems json scheme array validator
@Default json schema default value

Per message annotation

annotation description
@RootNode If there are multiple types without an parent you can give a hint to the root node with this annotation.

Head annotation

annotation description
@Option In head of your file you can place options for the parser

Head annotation "Option"

The @Option have to follow by space separated options key and another space separated value

// @Option primitiveTypesWithLimits false

message Point {

}

Possible options are:

option description def
primitiveTypesWithLimits If you dont like to get default Min and Max limits for primitive types, you can set this option to false true