clarify calculation of max timeout when using RENOVATE_X_GITLAB_AUTO_MERGEABLE_CHECK_ATTEMPS

[sebhoss]

What would you like help with?

I would like help with my configuration

How are you running Renovate?

Self-hosted

If you're self-hosting Renovate, tell us which platform (GitHub, GitLab, etc) and which version of Renovate.

GitLab

Please tell us more about your question or problem

https://docs.renovatebot.com/self-hosted-experimental/#renovate_x_gitlab_auto_mergeable_check_attemps mentions that the formula is RENOVATE_X_GITLAB_MERGE_REQUEST_DELAY * attempt * attempt. The same page mentions that RENOVATE_X_GITLAB_MERGE_REQUEST_DELAY is 250ms by default and RENOVATE_X_GITLAB_AUTO_MERGEABLE_CHECK_ATTEMPS is 5 by default. How does 250ms * 5 * 5 (= 6250ms = 6.25s) come out as 13.75s?

Logs (if relevant)

Logs

Replace this text with your logs, between the starting and ending triple backticks

[rarkins]

It backs off with each attempt. Search the source code to confirm

[sebhoss]

ok thanks

[HonkingGoose]

I think this is the code you want to read:

renovate/lib/modules/platform/gitlab/index.ts

Lines 647 to 737 in da3872e

	async function tryPrAutomerge(
	pr: number,
	platformOptions: PlatformPrOptions | undefined,
	): Promise<void> {
	if (platformOptions?.usePlatformAutomerge) {
	try {
	if (platformOptions?.gitLabIgnoreApprovals) {
	await ignoreApprovals(pr);
	}
	// https://docs.gitlab.com/ee/api/merge_requests.html#merge-status
	const desiredDetailedMergeStatus = [
	'mergeable',
	'ci_still_running',
	'not_approved',
	];
	const desiredPipelineStatus = [
	'failed', // don't lose time if pipeline failed
	'running', // pipeline is running, no need to wait for it
	];
	const desiredStatus = 'can_be_merged';
	// The default value of 5 attempts results in max. 13.75 seconds timeout if no pipeline created.
	const retryTimes = parseInteger(
	process.env.RENOVATE_X_GITLAB_AUTO_MERGEABLE_CHECK_ATTEMPS,
	5,
	);
	const mergeDelay = parseInteger(
	process.env.RENOVATE_X_GITLAB_MERGE_REQUEST_DELAY,
	250,
	);
	// Check for correct merge request status before setting `merge_when_pipeline_succeeds` to `true`.
	for (let attempt = 1; attempt <= retryTimes; attempt += 1) {
	const { body } = await gitlabApi.getJson<{
	merge_status: string;
	detailed_merge_status?: string;
	pipeline: {
	status: string;
	};
	}>(`projects/${config.repository}/merge_requests/${pr}`, {
	memCache: false,
	});
	// detailed_merge_status is available with Gitlab >=15.6.0
	const use_detailed_merge_status = !!body.detailed_merge_status;
	const detailed_merge_status_check =
	use_detailed_merge_status &&
	desiredDetailedMergeStatus.includes(body.detailed_merge_status!);
	// merge_status is deprecated with Gitlab >= 15.6
	const deprecated_merge_status_check =
	!use_detailed_merge_status && body.merge_status === desiredStatus;
	// Only continue if the merge request can be merged and has a pipeline.
	if (
	(detailed_merge_status_check || deprecated_merge_status_check) &&
	body.pipeline !== null &&
	desiredPipelineStatus.includes(body.pipeline.status)
	) {
	break;
	}
	logger.debug(`PR not yet in mergeable state. Retrying ${attempt}`);
	await setTimeout(mergeDelay * attempt ** 2); // exponential backoff
	}
	// Even if Gitlab returns a "merge-able" merge request status, enabling auto-merge sometimes
	// returns a 405 Method Not Allowed. It seems to be a timing issue within Gitlab.
	for (let attempt = 1; attempt <= retryTimes; attempt += 1) {
	try {
	await gitlabApi.putJson(
	`projects/${config.repository}/merge_requests/${pr}/merge`,
	{
	body: {
	should_remove_source_branch: true,
	merge_when_pipeline_succeeds: true,
	},
	},
	);
	break;
	} catch (err) {
	logger.debug(
	{ err },
	`Automerge on PR creation failed. Retrying ${attempt}`,
	);
	}
	await setTimeout(mergeDelay * attempt ** 2); // exponential backoff
	}
	} catch (err) /* istanbul ignore next */ {
	logger.debug({ err }, 'Automerge on PR creation failed');
	}
	}
	}