Execution Stages
How the execution stages work in DevZero.
Overview
Recipes have three execution stages that you can customize:
- Build-time: when recipe is getting saved, after validation.
- Launch-time: when a workspace is being launched from a recipe.
- Run-time: when a workspace is running (your active coding, app runtime environment)
Irrespective of the stage, command blocks will be executed in the order in which they are specified in the recipe.
Build-time
This stage should be used when caching of the build is helpful, i.e., pre-builds. Our builder uses the YAML specification to create container images that are then run as workspaces, the build images are layered and cached to improve subsequent workspace launch times.
Each command block can be thought of as a layer in a Docker image. They are wrapped in a script and executed within a bash context. In case directory is specified:
- if absolute, it will be used
- if relative, it will be relative to
/home/devzero - if unspecified, it will default to
/home/devzero
name is used to help reference and understand what is being achieved in a command block.
When invoking binaries, its always best-practice to reference them by their
absolute paths. For example, /usr/local/go/bin/go instead of go. This
relates to the following warning block.
Environment variable set by calling export are not going to be available in
subsequent command blocks. To use them in subsequent blocks, either write to
some file, or to /etc/environment. Please see the previous info section for
more ways to better utilize this.
While recipe builds are cached, updating a lower layer (eg: the first step in your build steps) will cause the cache to get invalidated for all future steps. Therefore, if you edit step 1 in a 5-step recipe, steps 2, 3, 4 and 5 will get rebuilt. If you just edit step 5, the previous steps will be served out of the cache.
Here's an example of some build-time steps:
For more examples, see check the build commands in our starter-templates.
Use-cases:
- Users in your team don't need to wait for workspaces to build.
- Users in your team want to start with workspaces that are already configured with golden paths.
Launch-time
These steps are run using systemctl units at launch-time. Command blocks will be executed in the order in which they are specified in the recipe.
The launch block is used for commands to be executed as launch-time steps.
Other than that, the same rules from the Build-time stage apply.
Here's an example of some launch-time steps:
