moleculer-grpc-api

Moleculer gRPC API mixin for Moleculer API Gateway

Features

Install

npm i moleculer-grpc-api moleculer-web

Usage

helloworld.proto

syntax = "proto3";
package helloworld;

// The greeting service definition.
service Greeter {
  // Sends a greeting
  rpc SayHello (HelloRequest) returns (HelloReply) {}
}

// The request message containing the user's name.
message HelloRequest {
  string name = 1;
}

// The response message containing the greetings
message HelloReply {
  string message = 1;
}

This example demonstrates how to setup a Moleculer API Gateway with gRPC mixin in order to handle incoming gRPC requests.

"use strict";

const { GrpcService } = require("moleculer-grpc-api");

module.exports = {
    name: "greeter",

    mixins: [

        // gRPC Server
        GrpcService({

            // Directory with you .proto files
            directory: `${dirname}/../protos`,

            // gRPC port. Default: 50051
            port: `50051`,

            // List of actions available. ${protoPackage}.${protoService}/${serviceName}: ${moleculerService}.${moculerAction}
            aliases: {
                'helloworld.Greeter': {
                    'sayHello': 'greeter.sayHello'
                }
            },

            // Authentication action to populate ctx.user using header
            authentication: {
                action: "greeter.currentUser",
                params: {
                    accessToken: "12345"
                }
            },
        })
    ],

    actions: {
        sayHello: {
            async handler(ctx) {
                this.logger.info("[INFO]:::: handler -> ctx.params", ctx.params);
                this.logger.info("[INFO]:::: handler -> metadata", ctx.meta.user);
                return { message: `Hello ${ctx.params.name}` };
            },
        },

        currentUser: {
            async handler(ctx) {
                const accessToken = ctx.params["access-token"];

                if (accessToken) {
                    if (accessToken === "12345") {
                        // valid credentials
                        return { id: 1, username: "john.doe", name: "John Doe" };
                    } else {
                        // invalid credentials
                        throw new MoleculerError("Unauthorize user", 401, null, { accessToken });
                    }
                } else {
                    // anonymous user
                    return null;
                }
            },
        },
    },
};

Start your Moleculer project and send gRPC requests.

Contribution

Please send pull requests improving the usage and fixing bugs, improving documentation and providing better examples, or providing some testing, because these things are important.

License

The project is available under the MIT license.