swagger-parser

What is swagger-parser?

swagger-parser is a powerful npm package that allows you to parse, validate, and dereference Swagger (OpenAPI) definitions. It helps in ensuring that your API definitions are correct and can be used to resolve $ref pointers to simplify the API documentation.

What are swagger-parser's main functionalities?

Parse

This feature allows you to parse a Swagger (OpenAPI) definition file. The code sample demonstrates how to parse a Swagger file and log the API name and version.

const SwaggerParser = require('swagger-parser');

SwaggerParser.parse('path/to/your/swagger.yaml')
  .then(api => {
    console.log('API name: %s, Version: %s', api.info.title, api.info.version);
  })
  .catch(err => {
    console.error(err);
  });

Validate

This feature allows you to validate a Swagger (OpenAPI) definition file. The code sample demonstrates how to validate a Swagger file and log whether the API is valid or not.

const SwaggerParser = require('swagger-parser');

SwaggerParser.validate('path/to/your/swagger.yaml')
  .then(api => {
    console.log('API is valid:', api);
  })
  .catch(err => {
    console.error('API is invalid:', err);
  });

Dereference

This feature allows you to dereference $ref pointers in a Swagger (OpenAPI) definition file. The code sample demonstrates how to dereference a Swagger file and log the dereferenced API.

const SwaggerParser = require('swagger-parser');

SwaggerParser.dereference('path/to/your/swagger.yaml')
  .then(api => {
    console.log('Dereferenced API:', api);
  })
  .catch(err => {
    console.error(err);
  });

Bundle

This feature allows you to bundle all external $ref pointers into a single file. The code sample demonstrates how to bundle a Swagger file and log the bundled API.

const SwaggerParser = require('swagger-parser');

SwaggerParser.bundle('path/to/your/swagger.yaml')
  .then(api => {
    console.log('Bundled API:', api);
  })
  .catch(err => {
    console.error(err);
  });

Other packages similar to swagger-parser

openapi-schema-validator

openapi-schema-validator is a package that validates OpenAPI 3.0 schemas. It focuses on schema validation and does not provide parsing or dereferencing functionalities like swagger-parser.

swagger-jsdoc

swagger-jsdoc is a package that generates Swagger (OpenAPI) definitions from JSDoc comments in your code. It is more focused on generating documentation from code comments rather than parsing and validating existing Swagger files.

swagger-client

swagger-client is a package that provides a JavaScript client for interacting with Swagger (OpenAPI) APIs. It includes functionalities for making API requests and handling responses, but it does not focus on parsing or validating Swagger definitions.

README

Swagger-Parser

Parses, validates, and dereferences your Swagger specs

Features

• Supports Swagger specs in JSON or YAML format
• Validates against the official Swagger 2.0 schema
• Dereferences all $ref pointers, including pointers to external URLs
• Nested $ref pointers are supported, even in external URLs
• Multiple $ref pointers to the same definition are resolved to the same object instance, thus maintaining strict reference equality

Basic Example

swagger.parser.parse("path/to/my/swagger.yaml", function(err, swagger) {
  if (err) {
    console.error("There's an error in the Swagger file: " + err.message);
    return;
  }

  console.log("Your API is " + swagger.info.title + ", version " + swagger.info.version);
});

The swagger parameter that is passed to the callback function is a fully-parsed, validated, and dereferenced Swagger Object.

Installation and Use

Node

npm install swagger-parser

Then add this to your Node script:

var parser = require("swagger-parser");
parser.parse('path/to/my/swagger.yaml', function(err, swagger) { ... });

Bower

bower install swagger-parser

Then add this to your HTML page:

<script src="bower_components/swagger-parser/dist/swagger-parser.js"></script>
<script>
    swagger.parser.parse('http://mysite.com/path/to/my/swagger.yaml', function(err, swagger) { ... });
</script>

AMD (Require.js)

Just add swagger-parser to your AMD module's dependencies, or require("swagger-parser") explicitly.

define("myModule", ["swagger-parser"], function(parser) {
    parser.parse('http://mysite.com/path/to/my/swagger.yaml', function(err, swagger) { ... });
});

Options

The parse function accepts an optional options parameter, like this:

var options = { 
    dereferencePointers: false, 
    validateSpec: false 
};
parser.parse("path/to/my/swagger.yaml", options, function(err, swaggerObject) {
  ...
});

Available options are as follows:

• parseYaml (default: true) - Determines whether the parser will allow Swagger specs in YAML format. If set to false, then only JSON will be allowed.

• dereferencePointers (default: true) - Determines whether $ref pointers will be dereferenced. If set to false, then the resulting SwaggerObject will contain Reference Objects instead of the objects they reference.

• dereferenceExternalPointers (default: true) - Determines whether $ref pointers will be dereferenced if they point to external files (e.g. "http://company.com/my/schema.yaml"). If set to false then the resulting SwaggerObject will contain Reference Objects for external pointers instead of the objects they reference.

• validateSpec (default: true) - Determines whether your Swagger spec will be validated against the official Swagger schema. If set to false, then the resulting Swagger Object may be missing properties, have properties of the wrong data type, etc.

Contributing

I welcome any contributions, enhancements, and bug-fixes. File an issue on GitHub and submit a pull request. Use JSHint to make sure your code passes muster. (see .jshintrc).

Here are some things currently on the to-do list:

• Recursive (circular) $ref pointers - Recursive (circular) $ref pointers are not currently supported. So something like this won't work:

person:
  properties:
    name:
      type: string
    spouse:
      type:
        $ref: person

License

Swagger-Parser is 100% free and open-source, under the MIT license. Use it however you want.