Skip to content
Drupal 8 Migrations by Example. Created by Mauricio Dinarte (@dinarcon). http://bit.ly/migrations-by-example
Branch: master
Clone or download
Fetching latest commit…
Cannot retrieve the latest commit at this time.
Permalink
Type Name Latest commit message Commit time
Failed to load latest commit information.
config/install Remove reference to running migrations from the UI Jan 17, 2019
mbe_professors_setup
migrations
sources Use proper quotes in HTML attribute Oct 25, 2018
README.md Provide more instructions about module location Jun 5, 2019
composer.json Initial commit Apr 10, 2018
mbe_professors.info.yml Add MBE to module names Apr 8, 2019

README.md

Drupal 8 Migrations by Example

A demo module created by Mauricio Dinarte (@dinarcon) to explain migrations concepts in Drupal 8.

This module has been used in conference talks to explain migration concetps. Find more information at:

Dependencies

The following projects are required to run this demo. The version number indicates which version was last used for testing.

Examples

This demo includes 3 migration configurations.

  • mbe_book_paragraph for importing data into paragraphs entities. There are no dependencies on other migrations.
  • mbe_photo_field for importing data into file entities. There are no dependencies on other migrations.
  • mbe_professors for importing data into node entities. This depend on other migrations to be run before: mbe_book_paragraph and mbe_photo_field.

Instructions

  • Install module dependencies via composer: composer require 'drupal/paragraphs:^1.8' 'drupal/address:^1.7' 'drupal/migrate_plus:^4.2' 'drupal/migrate_source_csv:^2.2' 'drupal/migrate_tools:^4.1'
  • If you do not have Drush available, install the latest version via composer: composer require drush/drush. After this step, you may call it via ./vendor/bin/drush.
  • Make sure that your Drupal installation has a /modules/custom folder. The modules folder should exist, but the custom sub-folder might not. Create it if needed.
  • Download the demo module contained in this repository into the /modules/custom folder. You can do this by cloning this repository or downloading a ZIP file. Important: The name of the folder containing this demo must ve mbe_professors. If you get it from the ZIP file the folder might be named mbe_professors-master. If that is the case, rename the folder to mbe_professors to prevent errors reading the CSV files.
  • Verify that the CSV files are in the proper location. See instructions below.
  • Enable the Professors Example Migration (mbe_professors) module.
  • Run migrations using drush. See instructions below.

CSV files location

The path configuration for the CSV source plugin accepts an absolute path or relative path from the Drupal installation folder.

The examples use a relative path and it is assumed that you place this demo module in a modules/custom folder. Therefore, the CSV files will be located at modules/custom/mbe_professors/sources/.

This would look similar to:

.
|-- autoload.php
|-- core
|-- index.php
|-- modules
|   |-- contrib
|   |   |-- address
|   |   |-- entity_reference_revisions
|   |   |-- migrate_plus
|   |   |-- migrate_source_csv
|   |   |-- migrate_tools
|   |   `-- paragraphs
|   `-- custom
|       `-- mbe_professors
|           |-- composer.json
|           |-- config
|           |-- mbe_professors.info.yml
|           |-- mbe_professors_setup
|           |-- migrations
|           |-- README.md
|           `-- sources
|-- profiles
|-- robots.txt
|-- sites
|-- themes
|-- update.php
`-- web.config

Not having the source CSV files in the proper location would trigger and error similar to:

[error]  Migration failed with source plugin exception: File path (modules/custom/mbe_professors/sources/mbe_book_paragraph.csv) does not exist.

If you want to place the files in a different location, you need to update the path in the corresponding configuration files. That is the source:path setting in the migration files.

Running the migrations

The Migrate Tools module provides drush commands to run the migrations.

drush migrate:import mbe_book_paragraph
drush migrate:import mbe_photo_field
drush migrate:import mbe_professors

Note: The commands above work for Drush 9. In Drush 8 the command names and aliases are different. Execute drush list --filter=migrate to verify the proper commands for your version of Drush.

After the migrations are run successfully, visit /professors to see the content that was imported.

Gotcha

There is an issue when rolling back a migration that depends on another one that interacts with entity revisions. This affects paragraphs migrations.

For this particular demo, if the mbe_professors is rolled back and later imported again, the book paragraphs will not be associated with the nodes.

To fix this, the dependent migration mbe_book_paragraph also needs to be rolled back and migrated again. This can be done via the UI or with the following drush commands:

drush migrate:rollback mbe_professors
drush migrate:rollback mbe_book_paragraph
drush migrate:import mbe_book_paragraph
drush migrate:import mbe_professors

Note: The commands above work for Drush 9. In Drush 8 the command names and aliases are different. Execute drush list --filter=migrate to verify the proper commands for your version of Drush.

You can’t perform that action at this time.