/bx-blue-green

zero-downtime deployment for Cloud Foundry applications

Primary LanguageShellOtherNOASSERTION

Blue-green deployments for Cloud Foundry based Bluemix apps

Allows zero-downtime deployments of applications within Bluemix, with no additional setup needed.

This repo is heavily based off of cf-blue-green

When to use bx-blue-green instead of cf-blue-green

This project uses the bluemix command line directly allowing it to leverage some of the new features added to bluemix.

The Bluemic CLI adds extra functionality to Cloud Foundry command line, if you are deploying onto bluemix, it is best to migrate over to the

Bluemix API key

To generate your Bluemix API key follow these steps:

demo

alternatively you can run

bluemix iam api-key-create <key-name> -d <description> -f <output-file>

Once the key is created, you may create an environment variable with the key BLUEMIX_API_KEY and when running bx login it will check for that variable first and if it exists, it will log you in.

Usage

  1. Install the bx CLI v0.6.0+.
  2. Run npm install -g https://github.com/andresfvilla/bx-blue-green.
    • See Notes below for non-Node installation.
  3. Run bx-blue-green <appname> (instead of bx cf push) from your application directory to deploy.

This creates a copy of your already-running application, and safely switches traffic over to it. It's recommended that you try this script on a non-production application environment first, just to ensure that everything is switched over properly.

Notes

Manual installation

The script is distributed via NPM, but doesn't actually require Node.js beyond that. If you don't want to install Node, simply:

  1. Download the script.
  2. Run chmod a+x bx-blue-green.
  3. Move the file somewhere in your PATH.

Using with Travis

Travis supports continuous deployment, which will automatically deploy your application after its tests pass on a specified branch. To use bx-blue-green with Travis, you need to use a script provider instead of the default Cloud Foundry provider. Your Cloud Foundry settings are read from environment variables.

Set up continuous deployment with the following settings in your .travis.yml file:

To add an encrypted Bluemix API key use travis encrypt BLUEMIX_API_KEY=<api-key> --add

sudo: true
env:
  global:
  - BX_APP=[app name]
  - BX_API=[API endpoint]
  - BX_ORGANIZATION=[organization]
  - BX_SPACE=[space]
  - BX_SLEEP=[# seconds to wait before swapping BLUE with GREEN]
  - secure: [BLUEMIX_API_KEY=[encrypted with Travis](http://docs.travis-ci.com/user/environment-variables/#Encrypted-Variables)]
before_deploy: npm install -g https://github.com/andresfvilla/bx-blue-green
deploy:
  provider: script
  script: bx-blue-green-travis
  on:
    branch: [git branch you want to deploy]

BX_SLEEP defines the number of seconds to sleep before replacing BLUE with GREEN. Useful when the new application requires some time to start.

Manifests

bx-blue-green creates a temporary manifest from your live application, meaning that it ignores the manifest.yml in your directory, if you have one. To deploy any changes to your manifest, use bx cf push directly.

Multiple domains

The script fails on apps with multiple domains, because the domains in the manifest are in the form of a list:

domain:
  - 18f.gov
  - digitalgov.gov

To work around this, use the env var B_DOMAIN for the domain you'd like the B instance to use.

Resources

More information about blue-green deployment, all of which this script drew from.