loopback-migration-tool

loopback-migration-tool expose the lb-migration script that ables you easy handle migrations and seeders for Loopback.io

Usage

Install Global

Install with Yarn

yarn global add loopback-migration-tool

or install with NPM

npm i -g loopback-migration-tool

Migrate all your models on all datasources.

lb-migration migrate

Migrate all your models on specific datasources.

lb-migration migrate --ds=datasource1 datasource2

Migrate specific models on specific datasources.

lb-migration migrate --ds=datasource1 datasource2 --model=model1 model2 model3

Migrate specific models using autoupdate method.

lb-migration migrate --model=model1 model2 model3 --method=update

Seed your models with files in ./seeds/*.js.

lb-migration seed

Seed your models with files in multiple locations.

lb-migration seed --src=path/to/files1/*.js path/to/files2/*.js path/to/files3/*.js  

Install as dev dependency

Install with Yarn

yarn add loopback-migration-tool --dev

or install with NPM

npm i loopback-migration-tool --save-dev

In your project root.

node_modules/.bin/lb-migration migrate [options] 

options

.lb-migrationrc.json

You can use a .lb-migrationrc.json to save your common migration settings.

Global options

| Property | Description | Type | Values | Default | As argument | |:--------: |:---------------------------------------------: |:------: |:------: |:--------------------: |:------------------------------------------------------------: | | app | Path to your loopback applicationmain file. | String | | ./server/server.js | -a --app --loopback-app |

migrate

Important: Loopback's datasources uses two methods to migrate your models.

• Auto-migration: Drop existing schema objects if they exist, and re-create them based on model definitions. Existing data will be lost.
• Auto-update: Detect the difference between schema objects and model definitions, and alter the database schema objects. Keep existing data.

Be careful what method must you use.

| Property | Description | Type | Values | Default | As argument | |:----------: |:--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------: |:---------------------: |:-----------------: |:-------: |:-----------------------------: | | ds |Datasources that will be migrated.If empty or not present, all datasources will be migrates. | String, [String] | | [] | -d --ds --datasource | | model |Models in the selected datasourcesthat will be migrated. If empty or not present,all models in all selected datasources willbe migrates. Selected Models not presents inselected datasources will be not migrated. | [String] | | [] | --mod --model | | ignored-model |Models in the selected datasourcesthat will be not migrated. | [String] | | [] | --imod --ignored-model | | method |Loopback migration method to use.Loopback uses automigrate and autoupdate methodsfor migrations. | String | update migrate | migrate | -m --method |

seed

Important: seed command will destroy all existing models' data calling to destroyAll method before start to seed them.

| Property | Description | Type | Values | Default | As argument | |:--------: |:---------------------------------: |:-----------: |:------: |:----------------: |:-----------------------------: | | src | File glob to your seeders files. | String | | "./seeds/*.js" | -s --src --sources |

Seeder file

A seeder file is just a js module that exports a function where you fill your model's data. Seeder files are executed in lexicographic order.

The exported function receive a loopback-app instance as argument where you can find all the loopback app data, that includes the app.models object.

You can find a example here

./seeds/index.js

module.exports = function (app, cb) {
    let Travel = app.models.Travel

    let promises = _.map(data, function (entry) {
        let passengers = entry.passengers
        delete entry.passengers

        return Travel.create(entry)
            .then((travel) => travel.passengers.create(passengers))
    })

    return Promise.all(promises) //Or you can use cb argument when all is done, but not both.
}