Blossom Docs
Blossom

Learn

Preview Every Pull Request

learn previews 2 min read

A Preview is a full copy of an Environment, such as production or staging, running another branch or pull request on its own URL. Full means the database too: each Preview gets its own, so you review a change running for real, end to end, before it ships. Ask your agent:

Create a Preview for each pull request.

Three Ways To Create Previews

Create How
By hand environment:preview:create --branch checkout-redesign
For every pull request pull_requests: true
For matching branches branch_pattern: preview/*

Turn On Pull Requests

blossom environment:preview:settings:init

preview_settings.yml:

preview_settings:
  expiry_days: 7 # delete after this many days without a deploy
  limit: 10 # most Previews at once
  pull_requests: true # each pull request into this branch gets a Preview
  # setup_command: bin/rails db:prepare db:seed # once, before the first release

blossom environment:preview:settings:update --environment environment-100 --data preview_settings.yml

The repository needs to come through a connected Git provider: GitHub, GitLab or Bitbucket.

What You Get

  • A full copy: the same Services, build settings and variables as its Environment, on the branch you’re testing.
  • Its own database: a PostgreSQL database of its own when your App links one, never production’s data.
  • Starting data: seed every new Preview’s database from a file, or run a setup command such as db:seed.
  • Its own URL, posted on the pull request on GitHub and updated on each push.
  • Access: open to your Account’s members by default; share a link with anyone else.
  • Variables: override one for Previews, such as a sandbox payment key.
  • Cleans up after itself: deleted when the pull request closes, or after 7 days without a deploy.

See Preview Environments for every setting, and Environment Access for who can open them.

On this page