@sportwarp/sportwarp-db v0.10.2

moleculer-db

Moleculer service to store entities in database.

Features

• default CRUD actions
• cached actions
• pagination support
• pluggable adapter (NeDB is the default memory adapter for testing & prototyping)
• official adapters for MongoDB, PostgreSQL, SQLite, MySQL, MSSQL.
• fields filtering
• populating
• encode/decode IDs
• entity lifecycle events for notifications

Install

$ npm install moleculer-db --save

Usage

"use strict";

const { ServiceBroker } = require("moleculer");
const DbService = require("moleculer-db");

const broker = new ServiceBroker();

// Create a DB service for `user` entities
broker.createService({
    name: "users",
    mixins: [DbService],

    settings: {
        fields: ["_id", "username", "name"]
    },

    afterConnected() {
        // Seed the DB with ˙this.create`
    }
});

broker.start()

// Create a new user
.then(() => broker.call("users.create", {
    username: "john",
    name: "John Doe",
    status: 1
}))

// Get all users
.then(() => broker.call("users.find").then(console.log));

// List users with pagination
.then(() => broker.call("users.list", { page: 2, pageSize: 10 }).then(console.log));

// Get a user
.then(() => broker.call("users.get", { id: 2 }).then(console.log));

// Update a user
.then(() => broker.call("users.update", { id: 2, name: "Jane Doe" }).then(console.log));

// Delete a user
.then(() => broker.call("users.remove", { id: 2 }).then(console.log));

Settings

Actions

find

Find entities by query.

Parameters

Results

Type: Array.<Object>

List of found entities.

count

Get count of entities by query.

Parameters

Results

Type: Number

Count of found entities.

list

List entities by filters and pagination results.

Parameters

Results

Type: Object

List of found entities and count.

create

Create a new entity.

Parameters

No input parameters.

Results

Type: Object

Saved entity.

insert

Create many new entities.

Parameters

Results

Type: Object, Array.<Object>

Saved entity(ies).

get

Get entity by ID.

Parameters

Results

Type: Object, Array.<Object>

Found entity(ies).

update

Update an entity by ID.

After update, clear the cache & call lifecycle events.

Parameters

No input parameters.

Results

Type: Object

Updated entity.

remove

Remove an entity by ID.

Parameters

Results

Type: Number

Count of removed entities.

Methods

getById

Get entity(ies) by ID(s).

Parameters

Results

Type: Object, Array.<Object>

Found entity(ies).

clearCache

Clear cached entities

Parameters

No input parameters.

Results

Type: Promise

encodeID

Encode ID of entity.

Parameters

Results

Type: any

decodeID

Decode ID of entity.

Parameters

Results

Type: any

Populating

The service supports to populate fields from other services. E.g.: if you have an author field in post entity, you can populate it with users service by ID of author. If the field is an Array of IDs, it will populate all entities via only one request.

Example of populate schema

broker.createService({
    name: "posts",
    mixins: [DbService],
    settings: {
        populates: {
            // Shorthand populate rule. Resolve the `voters` values with `users.get` action.
            "voters": "users.get",

            // Define the params of action call. It will receive only with username & full name of author.
            "author": {
                action: "users.get",
                params: {
                    fields: "username fullName"
                }
            },

            // Custom populator handler function
            "rate"(ids, rule, ctx) {
                return Promise.resolve(...);
            }
        }
    }
});

// List posts with populated authors
broker.call("posts.find", { populate: ["author"]}).then(console.log);

The populate parameter is available in find, list and get actions.

Lifecycle entity events

There are 3 lifecycle entity events which are called when entities are manipulated.

broker.createService({
    name: "posts",
    mixins: [DbService],
    settings: {},

    afterConnected() {
        this.logger.info("Connected successfully");
    },

    entityCreated(json, ctx) {
        this.logger.info("New entity created!");
    },

    entityUpdated(json, ctx) {
        // You can also access to Context
        this.logger.info(`Entity updated by '${ctx.meta.user.name}' user!`);
    },

    entityRemoved(json, ctx) {
        this.logger.info("Entity removed", json);
    },    
});

Please note! If you manipulate multiple entities (updateMany, removeMany), the json parameter will be a Number instead of entities!

Extend with custom actions

Naturally you can extend this service with your custom actions.

const DbService = require("moleculer-db");

module.exports = {
    name: "posts",
    mixins: [DbService],

    settings: {
        fields: ["_id", "title", "content", "votes"]
    },

    actions: {
        // Increment `votes` field by post ID
        vote(ctx) {
            return this.adapter.updateById(ctx.params.id, { $inc: { votes: 1 } });
        },

        // List posts of an author
        byAuthors(ctx) {
            return this.find({
                query: {
                    author: ctx.params.authorID
                },
                limit: ctx.params.limit || 10,
                sort: "-createdAt"
            });
        }
    }
}

Test

$ npm test

In development with watching

$ npm run ci

License

The project is available under the MIT license.

Contact

Copyright (c) 2016-2017 Ice Services