Context
-------
Building and testing Vault artifacts on pull requests and merges is
responsible for about 1/3rd of our overall spend on Vault CI. Of the
artifacts that we ship as part of a release, we do Enos testing scenarios
on the `linux/amd64` and `linux/arm64` binaries and their derivative
artifacts. The extended build artifacts for non-Linux platforms or less
common machine architectures are not tested at this time. They are built,
notarized, and signed as part of every pull request update and merge. As
we don't actually test these artifacts, the only gain we get from this
rather expensive behavior is that we wont merge a change that would prevent
Vault from building on one of the extended targets. Extended platform or
architecture changes are quite rare, so performing this work as frequently
as we do is costly in both monetary and developer time for little relative
safety benefit.
Goals
-----
Rethink and implement how and when we build binaries and artifacts of Vault
so that we can spend less money on repetitive work and while also reducing
the time it takes for the build and test pipelines to complete.
Solution
--------
Instead of building all release artifacts on every push, we'll opt to build
only our testable (core) artifacts. With this change we are introducing a
bit of risk. We could merge a change that breaks an extended platform and
only find out after the fact when we trigger a complete build for a release.
We'll hedge against that risk by building all of the release targets on a
scheduled cadence to ensure that they are still buildable.
We'll make building all of the targets optional on any pull request by
use of a `build/all` label on the pull request.
Further considerations
----------------------
* We want to reduce the total number of workflows and runners for all of our
pipelines if possible. As each workflow runner has infrastructure cost and
runner time penalties, using a single runner over many is often preferred.
* Many of our jobs runners have been optimized for cost and performance. We
should simplify the choices of which runners to use.
* CRT requires us to use the same build workflow in both CE and Ent.
Historically that meant that modifying `build.yml` in CE would result in a
merge conflict with `build.yml` in Ent, and break our merge workflows.
* Workflow flow control in both `build.yml` and `ci.yml` can be quite
complicated, as each needs to maintain compatibility whether executed as CE
or Ent, and when triggered with various Github events like pull_request,
push, and workflow_call, each with their own requirements.
* Many jobs utilize similar patterns of flow control and metadata but are not
reusable.
* Workflow call depth has a maximum of four, so we need to be quite
considerate when calling other workflows.
* Called workflows can only have 10 inputs.
Implementation
--------------
* Refactor the `build.yml` workflow to be agnostic to whether or not it is
executing in CE or Ent. That makes future updates to the build much easier
as we won't have to worry about merge conflicts when the change is merged
downstream.
* Extract common steps in workflows into composite actions that we can reuse.
* Fix bugs where some but not all workflows would use different Git
references when building and testing a pull request.
* We rewrite the application, docs, and UI change helpers as a composite
action. This allows us to re-use this logic to make consistent behavior
choices across build and CI.
* We combine several `build.yml` and `ci.yml` jobs into our final job.
This reduces the number of workflows required for the same behavior while
saving time overall.
* Update most of our action pins.
Results
-------
| Metric | Before | After | Diff |
|-------------------|----------|---------|-------|
| Duration: | ~14-18m | ~15-18m | ~ = |
| Workflows: | 43 | 18 | - 58% |
| Billable time: | ~1h15m | 16m | - 79% |
| Saved artifacts: | 34 | 12 | - 65% |
Infra costs should map closely to billable time.
Network I/O costs should map closely to the workflow count.
Storage costs should map directly with saved artifacts.
We could probably get parity with duration by getting more clever with
our UBI container build, as that's where we're seeing the increase. I'm
not yet concerned as it takes roughly the same time for this job to
complete as it did before.
While the CI workflow was not the focus on the PR, some shared
refactoring does show some marginal improvements there.
| Metric | Before | After | Diff |
|-------------------|----------|----------|--------|
| Duration: | ~24m | ~12.75m | - 15% |
| Workflows: | 55 | 47 | - 8% |
| Billable time: | ~4h20m | ~3h36m | - 7% |
Further focus on streamlining the CI workflows would likely result in a
few more marginal improvements, but nothing on the order like we've seen
with the build workflow.
Signed-off-by: Ryan Cragun <me@ryan.ec>
We're on a quest to reduce our pipeline execution time to both enhance
our developer productivity but also to reduce the overall cost of the CI
pipeline. The strategy we use here reduces workflow execution time and
network I/O cost by reducing our module cache size and using binary
external tools when possible. We no longer download modules and build
many of the external tools thousands of times a day.
Our previous process of installing internal and external developer tools
was scattered and inconsistent. Some tools were installed via `go
generate -tags tools ./tools/...`,
others via various `make` targets, and some only in Github Actions
workflows. This process led to some undesirable side effects:
* The modules of some dev and test tools were included with those
of the Vault project. This leads to us having to manage our own
Go modules with those of external tools. Prior to Go 1.16 this
was the recommended way to handle external tools, but now
`go install tool@version` is the recommended way to handle
external tools that need to be build from source as it supports
specific versions but does not modify the go.mod.
* Due to Github cache constraints we combine our build and test Go
module caches together, but having our developer tools as deps in
our module results in a larger cache which is downloaded on every
build and test workflow runner. Removing the external tools that were
included in our go.mod reduced the expanded module cache by size
by ~300MB, thus saving time and network I/O costs when downloading
the module cache.
* Not all of our developer tools were included in our modules. Some were
being installed with `go install` or `go run`, so they didn't take
advantage of a single module cache. This resulted in us downloading
Go modules on every CI and Build runner in order to build our
external tools.
* Building our developer tools from source in CI is slow. Where possible
we can prefer to use pre-built binaries in CI workflows. No more
module download or tool compiles if we can avoid them.
I've refactored how we define internal and external build tools
in our Makefile and added several new targets to handle both building
the developer tools locally for development and verifying that they are
available. This allows for an easy developer bootstrap while also
supporting installation of many of the external developer tools from
pre-build binaries in CI. This reduces our network IO and run time
across nearly all of our actions runners.
While working on this I caught and resolved a few unrelated issue:
* Both our Go and Proto format checks we're being run incorrectly. In
CI they we're writing changes but not failing if changes were
detected. The Go was less of a problem as we have git hooks that
are intended to enforce formatting, however we drifted over time.
* Our Git hooks couldn't handle removing a Go file without failing. I
moved the diff check into the new Go helper and updated it to handle
removing files.
* I combined a few separate scripts and into helpers and added a few
new capabilities.
* I refactored how we install Go modules to make it easier to download
and tidy all of the projects go.mod's.
* Refactor our internal and external tool installation and verification
into a tools.sh helper.
* Combined more complex Go verification into `scripts/go-helper.sh` and
utilize it in the `Makefile` and git commit hooks.
* Add `Makefile` targets for executing our various tools.sh helpers.
* Update our existing `make` targets to use new tool targets.
* Normalize our various scripts and targets output to have a consistent
output format.
* In CI, install many of our external dependencies as binaries wherever
possible. When not possible we'll build them from scratch but not mess
with the shared module cache.
* [QT-641] Remove our external build tools from our project Go modules.
* [QT-641] Remove extraneous `go list`'s from our `set-up-to` composite
action.
* Fix formatting and regen our protos
Signed-off-by: Ryan Cragun <me@ryan.ec>
