buildkite-agent env has --from-env-file and --print flags #1803
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| for _, e := range env { | ||
| k, v, _ := strings.Cut(e, "=") | ||
| envMap[k] = v | ||
| } |
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I suspect @moskyb's efforts to also use this command in windows will cause a merge conflict here.
This solves the problem of safely parsing BUILDKITE_ENV_FILE, and allows
for usage like this in a pre-command hook or similar:
local branch
branch="$(buildkite-agent env --from-env-file --print BUILDKITE_BRANCH)"
if [[ branch != "main" ]]; then
echo "This agent only builds branch 'main'"
exit 42
fi
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| if c.Bool("from-env-file") { | ||
| envMap, err = loadEnvFile(os.Getenv("BUILDKITE_ENV_FILE")) |
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This feels weird to me. I expect --from-env-file to take a value, but default to an environment variable, like our other options. But if we defaulted to the env file then it would break dumping of the current env as json.
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Yep. I like your idea of moving the current “dump entire process env as JSON” use-cases into a subcommand/flag(s), which then frees up the buildkite-agent env namespace to support some other environment-related use-cases.
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This feels like the same domain but a pretty orthogonal use case to the underlying command to dump the current env as json. I think it should be a separate command. Maybe something like: buildkite-agent env get NAMEBut it's unclear to me then which env it's getting. Build env? Job env? The current process? The env file, pointed at by an env (inception moment)? I would presume the current process env. Which feels odd, because I can Playing with some usage ... buildkite-agent env get NAME # current process env?
buildkite-agent env --env-file get NAME # from $BUILDKITE_ENV_FILE?
buildkite-agent env --env-file=... get NAME
buildkite-agent env --json-file=... get NAME??? Maybe the recently introduced command should also be a subcommand? |
Yeah I like that. Since the recently-added |
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The nice thing about subcommands is if we peer forwards to being able to set env from things which are not bash hooks, that could use |
Adds two flags to the
buildkite-agent envcommand introduced in #1781.By default,
buildkite-agent envloadsos.Environ()and prints it as a JSON object; it's mainly intended for internal use to capture a snapshot of environment before a hook runs, and detect changes afterwards.The new
--from-env-fileboolean flag sources the environment from the file named by$BUILDKITE_ENV_FILEinstead of fromos.Environ(), usingbufio.Scannerandstrconv.Unquote()to safely and correctly parse the quoting/escaping done by%qwhen the file was written:agent/agent/job_runner.go
Line 490 in 2aaefb6
The new
--print NAMEflag causes a single environment value to be printed in its raw unescaped form followed by a newline, instead of printing all vars as a JSON object.Combined, this solves the problem of safely parsing
BUILDKITE_ENV_FILE(which cannot be safely evaluated in a shell if it may contain untrusted user input) to access a single variable, and allows for usage like this in a pre-command hook or similar: