@janiscommerce/router-fetcher

router-fetcher

Maps services names, namespaces and methods defined in the API's schemas, to endpoints and HTTP methods for APIs's calls from any service.

Instalation

npm install @janiscommerce/router-fetcher

Configuration

Router-Fetcher uses a setting JSON file.

It's located in path/to/root/[MS_PATH]/config/.janiscommercerc.json

Needs the following fields

• routerConfig, object with URL to get Endpoints and Schemas.

Example

In path/to/root/[MS_PATH]/config/.janiscommercerc.json.

{
	"routerConfig": {
		"endpoint": "http://valid-router:7999/api/endpoint",
		"schema": "http://valid-router:7999/api/services/{serviceName}/schema"
	}
}

API

• new RouterFetcher()

  Router-Fetcher Constructors

• getEndpoint(service, namespace, method, httpMethod)

  Get the endpoint data doing one request to the router.

  • service:
    • type String
    • The name of the microservice.
  • namespace
    • type String
    • The namespace of the microservice.
  • method
    • type String
    • The method of microservice.
  • httpMethod
    • type String
    • Verb of the request.

  Returns a Promise of RouterResponse object

• getSchema(service)

  Get the schema data of a service doing one request to the router.

  • service:
    • type String
    • The name of the microservice.

  Returns a Promise of RouterResponse object

Response Object

Response of Router for endpoints

• RouterResponse
  • endpoint
    • type: String
    • The endpoint of microservice.
  • httpMethod
    • type: String
    • The httpMethod of endpoint.

For Schemas requests, the response will be an object with the OpenAPI specification

Errors

The errors are informed with a RouterFetcherError.

• RouterFetcherError:
  • code:
    • type: Number
    • The status code of the error
  • message:
    • type: String
    • The status message of the response.
  • name:
    • type: String
    • value:
      • RouterFetcherError. If the response code is >= 400.
      • Other, Request Library Error.

Codes

The codes are the following:

Code	Description
2	Schema not found
3	Invalid Router Config Path
4	Endpoint not found
5	Request Library Errors

Usage

Make a request to "SAC" microservice with the namespace "claim-type" and method "list" and get its endpoints.

const RouterFetcher = require('@janiscommerce/router-fetcher');

const routerFetcher = new RouterFetcher();

try {

    const response = await routerFetcher.getEndpoint('sac', 'claim-type', 'list');

    /*
        Response example
        {
            "endpoint": "https://sac.janis.in/claim-types",
            "httpMethod: "GET"
        }
    */

} catch (err) {
    /*
        Error Response Example:
        {
            name: 'RouterFetcherError'
            message: 'Endpoint not found',
            code: 3
        }
    */
    if (err.name === `RouterFetcherError`) {
        // The code of the router response is >= 400.

    } else {
        // Fatal error of request library https://www.npmjs.com/package/request
    }
}

Make a request to "SAC" microservice and obtain its schemas.

const RouterFetcher = require('@janiscommerce/router-fetcher');

const routerFetcher = new RouterFetcher();

try {

    const response = await routerFetcher.getSchema('sac');

    /*
        Response example
        {
            servers: ["core"],
            tags: ["sac"],
            paths: {
                /sac/claim-type/list:
                    x-janis-namespace: claim-type,
                    x-janis-method: "list",
                    get: {
                        responses: {
                        '200': description: OK,
                        '400': description: Invalid parameters,
                        '401': description: Invalid authentication,
                        '403': description: Invalid permissions
                        }
                    }
                }
        }
    */

} catch(err) {
    /*
        Error Response Example:
        {
            name: 'RouterFetcherError'
            message: 'Schema not found',
            code: 2
        }
    */
    if(err.name === `RouterFetcherError`) {
        // The code of the router response is >= 400.

    } else {
        // Fatal error of request library https://www.npmjs.com/package/request
    }
}