Task-graph generation takes a collection of parameters as input, in the form of a JSON or YAML file.
During decision-task processing, some of these parameters are supplied on the command line or by environment variables. The decision task helpfully produces a full parameters file as one of its output artifacts. The other
mach taskgraph commands can take this file as input. This can be very helpful when working on a change to the task graph.
When experimenting with local runs of the task-graph generation, it is always best to find a recent decision task's
parameters.yml file, and modify that file if necessary, rather than starting from scratch. This ensures you have a complete set of parameters.
The properties of the parameters object are described here, divided rougly by topic.
The event that precipitated this decision task; one of
The repository from which to do an initial clone, utilizing any available caching.
The repository containing the changeset to be built. This may differ from
base_repository in cases where
base_repository is likely to be cached and only a few additional commits are needed from
The revision to check out; this can be a short revision string
For Mercurial repositories, this is the same as
head_rev. For git repositories, which do not allow pulling explicit revisions, this gives the symbolic ref containing
head_rev that should be pulled from
Email address indicating the person who made the push. Note that this value may be forged and must not be relied on for authentication.
The commit message
The ID from the
The timestamp of the push to the repository that triggered this decision task. Expressed as an integer seconds since the UNIX epoch.
The timestamp of the build date. Defaults to
pushdate and falls back to present time of taskgraph invocation. Expressed as an integer seconds since the UNIX epoch.
A formatted timestamp of
build_date. Expressed as a string with the following format: %Y%m%d%H%M%S
Another name for what may otherwise be called tree or branch or repository. This is the unqualified name, such as
The SCM level associated with this tree. This dictates the names of resources used in the generated tasks, and those tasks will fail if it is incorrect.
The "target set" is the set of task labels which must be included in a task graph. The task graph generation process will include any tasks required by those in the target set, recursively. In a decision task, this set can be specified programmatically using one of a variety of methods (e.g., parsing try syntax or reading a project-specific configuration file).
The method to use to determine the target task set. This is the suffix of one of the functions in
If true, then target tasks are eligible for optimization.