The Release Cycle

Our Hello World package from the previous section contains a single file, but other than that it doesn’t do much:

name: quickstart/hello-world
version: 0.0.@
description: 
logo: 

includes:
- README.md

build: 
deploy:

Build and test

The life cycle of almost every unit starts with a build step. This step is generally only run on developer’s workstations and CI servers to make sure all the artefacts that are necessary at deployment time are part of the package.

We can trigger the build step of an Escape plan using the escape run build command:

escape run build

Our almost empty Escape plan doesn’t define a build step however, so this step completes very quickly, but we can add one:

name: quickstart/hello-world
version: 0.0.@
description: 
logo: 

includes:
- README.md

build: hello_world.sh
deploy:

Now Escape expects this file to exist when we try and run the build again:

$ escape run build
Compile: Error: File 'hello_world.sh' was referenced in the escape plan, but it doesn't exist

Let’s do Escape a favour and create the hello_world.sh file:

cat > hello_world.sh <<EOF
#!/bin/bash

set -euf

echo "Hello World!"
EOF

And try that again:

$ escape run build
Build: Running build step /home/bspaans/src/workspace/escape/hello_world.sh.
Build: hello_world.sh: Hello World!
Build: ✔️ Completed build

After a build step we’d usually want to run a test step to make sure that what we’ve built the right thing:

escape run test

Again, we haven’t defined this field in our Escape plan, so this step completes quickly, but we can add a test field to make Escape run another script. However, our Hello World package currently doesn’t contain anything worth testing so we’ll skip this.

Deploy and smoke

We have a build phase that can be used to generate files, binaries, docs, etc. and then test them. Next, we want to be able to deploy these files into separate environments.

We can trigger the deploy step of an Escape plan using the escape run deploy command:

$ escape run deploy

We haven’t specified a deployment script however so this completes very quickly for us, but let’s re-use our “Hello World” script from before:

name: quickstart/hello-world
version: 0.0.@
description: 
logo: 

includes:
- README.md

build: hello_world.sh
deploy: hello_world.sh

$ escape run deploy
Deploy: Running deploy step /home/bspaans/src/workspace/escape/hello_world.sh.
Deploy: hello_world.sh: Hello World!
Deploy: ✔️ Successfully deployed hello-world-v0.0.1 with deployment name quickstart/hello-world in the dev environment.

Release

Running the release step will run the build, test, deploy, smoke, destroy, package and push steps in succession to make sure the unit is working end-to-end (although parts can be skipped see escape run release)

$ escape run release
Release: Releasing quickstart/hello-world-v0.0.1
  Build: Running build step /home/bspaans/src/workspace/escape/hello_world.sh.
  Build: hello_world.sh: Hello World!
  Build: ✔️ Completed build
  Test: ✔️ Tests passed.
  Destroy: ✔️ Destruction complete
  Deploy: Running deploy step /home/bspaans/src/workspace/escape/hello_world.sh.
  Deploy: hello_world.sh: Hello World!
  Deploy: ✔️ Successfully deployed hello-world-v0.0.1 with deployment name quickstart/hello-world in the dev environment.
  Smoke tests: ✔️ Smoke tests passed.
  Destroy: ✔️ Destruction complete
  Package: ✔️ Packaged quickstart/hello-world-v0.0.1 at /home/bspaans/src/workspace/escape/.escape/target/hello-world-v0.0.1.tgz
  Push: ✔️ Push successful.
Release: ✔️ Successfully released quickstart/hello-world-v0.0.1

As we can see our Hello World script gets run twice. So why does the release command run both the build and deploy step? Our general philosophy is that once a package is in the inventory all its steps should have been tested. The main thing that a package will be used for after publishing is deployments so it’s good to test this early.