What is @asyncapi/parser?
@asyncapi/parser is a powerful npm package designed to parse AsyncAPI documents. It allows developers to read, validate, and manipulate AsyncAPI specifications programmatically. This is particularly useful for generating documentation, creating mock servers, and integrating with other tools in the API development lifecycle.
What are @asyncapi/parser's main functionalities?
Parsing AsyncAPI Documents
This feature allows you to parse an AsyncAPI document from a JSON string. The parsed document can then be used for further processing or validation.
const { Parser } = require('@asyncapi/parser');
const parser = new Parser();
const asyncapiDocument = `{
"asyncapi": "2.0.0",
"info": {
"title": "Streetlights API",
"version": "1.0.0"
},
"channels": {
"light/measured": {
"description": "Channel for light measurement events",
"subscribe": {
"summary": "Receive light measurement events",
"message": {
"$ref": "#/components/messages/LightMeasured"
}
}
}
},
"components": {
"messages": {
"LightMeasured": {
"payload": {
"type": "object",
"properties": {
"lumens": {
"type": "integer"
}
}
}
}
}
}
}`;
parser.parse(asyncapiDocument)
.then(doc => console.log('Parsed document:', doc))
.catch(err => console.error('Error parsing document:', err));
Validating AsyncAPI Documents
This feature allows you to validate an AsyncAPI document after parsing it. It checks for any schema violations or inconsistencies in the document.
const { Parser } = require('@asyncapi/parser');
const parser = new Parser();
const asyncapiDocument = `{
"asyncapi": "2.0.0",
"info": {
"title": "Streetlights API",
"version": "1.0.0"
},
"channels": {
"light/measured": {
"description": "Channel for light measurement events",
"subscribe": {
"summary": "Receive light measurement events",
"message": {
"$ref": "#/components/messages/LightMeasured"
}
}
}
},
"components": {
"messages": {
"LightMeasured": {
"payload": {
"type": "object",
"properties": {
"lumens": {
"type": "integer"
}
}
}
}
}
}
}`;
parser.parse(asyncapiDocument)
.then(doc => {
const validationErrors = doc.validate();
if (validationErrors.length) {
console.error('Validation errors:', validationErrors);
} else {
console.log('Document is valid');
}
})
.catch(err => console.error('Error parsing document:', err));
Accessing Document Components
This feature allows you to access various components of the parsed AsyncAPI document, such as channels and messages. This is useful for generating documentation or creating mock servers.
const { Parser } = require('@asyncapi/parser');
const parser = new Parser();
const asyncapiDocument = `{
"asyncapi": "2.0.0",
"info": {
"title": "Streetlights API",
"version": "1.0.0"
},
"channels": {
"light/measured": {
"description": "Channel for light measurement events",
"subscribe": {
"summary": "Receive light measurement events",
"message": {
"$ref": "#/components/messages/LightMeasured"
}
}
}
},
"components": {
"messages": {
"LightMeasured": {
"payload": {
"type": "object",
"properties": {
"lumens": {
"type": "integer"
}
}
}
}
}
}
}`;
parser.parse(asyncapiDocument)
.then(doc => {
const channels = doc.channels();
console.log('Channels:', channels);
const messages = doc.components().messages();
console.log('Messages:', messages);
})
.catch(err => console.error('Error parsing document:', err));
Other packages similar to @asyncapi/parser
swagger-parser
swagger-parser is a powerful npm package for parsing, validating, and dereferencing Swagger (OpenAPI) documents. It offers similar functionalities to @asyncapi/parser but is focused on the OpenAPI specification. It is widely used for working with RESTful APIs.
openapi-schema-validator
openapi-schema-validator is a package designed to validate OpenAPI 3.0 schemas. While it does not offer parsing capabilities, it provides robust validation features similar to those found in @asyncapi/parser.
openapi-types
openapi-types is a TypeScript library that provides type definitions for OpenAPI specifications. It is useful for developers who want to ensure type safety when working with OpenAPI documents, similar to how @asyncapi/parser provides structure for AsyncAPI documents.