How can I get the commit id?

[cathaysia]

When I clone a repo, how can I get the commit id?

[EDMPhoenix]

When you clone a git repository, it downloads the entire history of the project, including all the commits. You can view the commit ID (also known as the commit hash) of each commit using the git log command.

The output will look something like this:

commit a8b9f34bcdf30cf6ae5325459a9d1f9f9153b204 (HEAD -> master, origin/master, origin/HEAD)
Author: Author Name <[email protected]>
Date:   Mon Jan 6 12:34:56 2024 -0500

    This is the most recent commit message

commit b3a7d76f445df2398333a4998b3aa0d713cb9a63
Author: Another Author <[email protected]>
Date:   Sun Jan 5 11:23:45 2024 -0500

    This is the second most recent commit message

In this example, a8b9f34bcdf30cf6ae5325459a9d1f9f9153b204 and b3a7d76f445df2398333a4998b3aa0d713cb9a63 are the commit IDs.

[cathaysia]

But how can I get it in buildbot? can I get the output of ShellCommand?

[EDMPhoenix]

Yes, you can use ShellCommand in Buildbot to run git commands and capture their output. This is done by creating a step in your build process that uses ShellCommand.

Here's an example of how to get all commit IDs:

from buildbot.plugins import *

factory = util.BuildFactory()
factory.addStep(steps.ShellCommand(command=["git", "log", "--pretty=format:'%H'"],
                                   workdir="build/src",
                                   logEnviron=False,
                                   decodeRC={0:SUCCESS, 1:FAILURE, 2:FAILURE, 3:FAILURE, 4:FAILURE, 5:FAILURE},
                                   name="Get Commit IDs",
                                   description="Getting all commit IDs..",
                                   descriptionDone="Got all commit IDs."))

In this case, we're running the git log --pretty=format:'%H' command, which will output just the commit IDs of all commits.

The workdir parameter is the directory where the command will be run, logEnviron is set to False to not log the environment variables, decodeRC is used to interpret the return code from the command, and name, description, and descriptionDone are just metadata for the step.

The output of the command will be logged by Buildbot, and can be viewed in the web UI.

Also, please note that all the commits will be shown as a single block of text. If you want each commit on a new line, you can modify the command to:

factory.addStep(steps.ShellCommand(command=["bash", "-c", "git log --pretty=format:'%H'"],

This will run the git log command in a bash shell, which will interpret the %n as a newline character.

[cathaysia]

Ok, thanks. :)

[EDMPhoenix]

My pleasure. Please feel free to ask any questions.

[cathaysia]

I hope to get the current commit id and then generate a file name based on the commit id, which is to achieve this effect:

hash = steps.ShellCommand(command=["git", "rev-parse", "HEAD"])
output_filename = f"libc.{hash}.so"

In addition to this, I also need to collect some buildinfo information. For example, compiler version, system version, etc. Although I could execute the bash command and then redirect the output into .buildinfo, such a ShellCommand would be cumbersome to write. Is there a simpler way? (For example, call the command and get its stdout like above)

[EDMPhoenix]

To achieve this in Buildbot, you can use the setProperty argument in ShellCommand to capture the output of the command as a property. After that, you can use the Interpolate function to create the filename based on the commit id property.

from buildbot.plugins import *

factory = util.BuildFactory()
factory.addStep(steps.ShellCommand(command=["git", "rev-parse", "HEAD"],
                                   workdir="build/src",
                                   logEnviron=False,
                                   decodeRC={0:SUCCESS},
                                   name="Get Commit ID",
                                   description="Getting commit ID..",
                                   descriptionDone="Got commit ID.",
                                   setProperty={"commit_id": util.Property('got_revision')}))

factory.addStep(steps.SetPropertyFromCommand(
    command='echo libc.$(git rev-parse HEAD).so',
    property='output_filename'))

factory.addStep(steps.ShellCommand(command=Interpolate("echo 'Filename: %%(prop:output_filename)s' > output.txt")))

In this case, the first step gets the git commit ID and stores it in the commit_id property.

The second step uses SetPropertyFromCommand to create a filename using the commit id and stores it in the output_filename property.

The third step uses the Interpolate function to replace %(prop:output_filename)s with the value of the output_filename property, and then echo this filename to output.txt.

As for collecting build information, you can indeed use a series of ShellCommand steps to execute the commands and redirect their output to a file. However, if you find it cumbersome to write, you could create a script that collects all the build information and then just call this script from Buildbot using ShellCommand. This would make your buildbot configuration simpler and the script can be used outside of buildbot as well.

[cathaysia]

thanks. you help me a lot. :)