theonedev/onedev · warning · NotAcceptableException

Another pull request already opened for this change

Error message

Another pull request already opened for this change

What it means

OneDev's DefaultPullRequestService.open() refuses to create a pull request when an open pull request already exists for the same target<-source branch pair. findOpen() is consulted first; if it returns a live PR, a NotAcceptableException (HTTP 406) is thrown because duplicate PRs for the same change would fragment review and merge state.

Source

Thrown at server-core/src/main/java/io/onedev/server/service/impl/DefaultPullRequestService.java:440

	@Transactional
	@Override
	public void open(PullRequest request) {
		Preconditions.checkArgument(request.isNew());

		var target = Preconditions.checkNotNull(request.getTarget(),
				"Pull request target must be set before calling open");
		var source = Preconditions.checkNotNull(request.getSource(),
				"Pull request source must be set before calling open");
		Preconditions.checkNotNull(request.getSubmitter(),
				"Pull request submitter must be set before calling open");

		if (target.equals(source))
			throw new NotAcceptableException("Source and target are the same");

		PullRequest existing = findOpen(target, source);
		if (existing != null)
			throw new NotAcceptableException("Another pull request already opened for this change");

		existing = findEffective(target, source);
		if (existing != null) {
			if (existing.isOpen())
				throw new NotAcceptableException("Another pull request already opened for this change");
			else
				throw new NotAcceptableException("Another pull request already merged the change");
		}

		if (request.getBaseCommitHash() == null) {
			ObjectId baseCommitId = gitService.getMergeBase(
					target.getProject(), target.getObjectId(),
					source.getProject(), source.getObjectId());
			if (baseCommitId == null)
				throw new NotAcceptableException("No common base for target and source");
			request.setBaseCommitHash(baseCommitId.name());
		}

View on GitHub (pinned to d44925c47c)

Solutions

1. Check findOpen()/list the project's open pull requests before calling open() and reuse the existing PR instead
2. Catch NotAcceptableException from open() and look up the existing PR to return its number/link to the user
3. Make automated PR creation idempotent: key scripts on the target/source branch pair and skip creation if one exists
4. If the existing PR is stale/wrong, close it first, then open the new one

Example fix

// before
pullRequestService.open(pullRequest); // throws if one already exists
// after
PullRequest existing = pullRequestService.findOpen(target, source);
if (existing == null)
    pullRequestService.open(pullRequest);
else
    logger.info("Reusing existing PR #{}", existing.getNumber());

PullRequest existing = pullRequestService.findOpen(target, source);
if (existing != null)
    return existing; // reuse instead of opening

try {
    pullRequestService.open(request);
} catch (NotAcceptableException e) {
    if (e.getMessage().contains("Another pull request already opened")) {
        PullRequest existing = pullRequestService.findOpen(target, source);
        redirect(existing);
    } else throw e;
}

When it happens

Trigger: Calling PullRequestService.open() (directly or via the 'new pull request' flow) when findOpen(target, source) returns a non-null PullRequest, i.e. an open PR with the exact same target and source branches already exists.

Common situations: Double-submitting the PR creation form after a page reload; scripting PR creation in CI that runs on every push without checking for an existing PR; two users creating the same PR concurrently.

Understand the failure class

Background: "Invalid state transition" errors: "status must be X, actually Y", "already rejected/charging/uninstalled", "cannot ... while running" — what they mean when a library rejects your call — this error's family across 31 libraries.

Related errors

• Reviewer not found:
• Pull request submitter cannot be reviewer
• Assignee not found:
• No permission to read code of source project:
• No permission to read code of target project:

AI-assisted analysis of theonedev/onedev@d44925c47c (2026-09-06). Data as JSON: /api/errors/62ba5a8417cad4e9. Report an issue: GitHub.