theonedev/onedev · error · ValidationException

Cannot link to self

Error message

Cannot link to self

What it means

Domain validation in IssueLink.validate: source and target issues are the same issue, which a self-link cannot represent (getLinked would be ambiguous); ValidationException is raised. Called from createLink, so the invalid link is rejected before persistence. Fix: link two distinct issues.

Source

Thrown at server-core/src/main/java/io/onedev/server/model/IssueLink.java:87

	public void setSpec(LinkSpec spec) {
		this.spec = spec;
	}
	
	public Issue getLinked(Issue issue) {
		return issue.equals(source)?target:source;
	}

	public int getPosition() {
		return position;
	}

	public void setPosition(int position) {
		this.position = position;
	}

	public void validate() {
		if (getSource().equals(getTarget()))
			throw new ValidationException("Cannot link to self");
		if (getSpec().getOpposite() != null) {
			if (getSource().getTargetLinks().stream()
					.anyMatch(it -> it.getSpec().equals(getSpec()) && it.getTarget().equals(getTarget())))
				throw new ValidationException("Source issue already linked to target issue via specified link spec");
			if (!getSpec().isMultiple()
					&& getSource().getTargetLinks().stream().anyMatch(it -> it.getSpec().equals(getSpec())))
				throw new ValidationException(
						"Link spec is not multiple and the source issue is already linked to another issue via this link spec");
			if (!getSpec().getParsedIssueQuery(getSource().getProject()).matches(getTarget()))
				throw new ValidationException("Link spec not allowed to link to the target issue");
			if (!getSpec().getOpposite().isMultiple()
					&& getTarget().getSourceLinks().stream().anyMatch(it -> it.getSpec().equals(getSpec())))
				throw new ValidationException(
						"Opposite side of link spec is not multiple and the target issue is already linked to another issue via this link spec");
			if (!getSpec().getOpposite().getParsedIssueQuery(getSource().getProject())
					.matches(getSource()))
				throw new ValidationException("Opposite side of link spec not allowed to link to the source issue");
		} else {

View on GitHub (pinned to d44925c47c)

Solutions

1. Ensure the target issue id differs from the source issue id before calling createLink
2. Guard scripts: skip linking when source.getId() == target.getId()
3. Fix import/bulk data so self-references are removed

Example fix

// before
issueLinkService.createLink(issue, issue, spec);  // self link
// after
if (!target.equals(issue)) issueLinkService.createLink(issue, target, spec);

if (source.equals(target)) { /* skip or reject link */ }

try { issueLinkService.createLink(source, target, spec); } catch (ValidationException e) { log.warn("Link rejected: " + e.getMessage()); }

When it happens

Trigger: Creating an issue link (via UI, API, or createLink) where source issue equals target issue, e.g. passing the same issue id for both ends.

Common situations: Automation scripts computing the link target incorrectly (off-by-one/wrong variable); UI bugs allowing self-selection; bulk import scripts linking an issue to itself; copy-paste of issue numbers.

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

• Source issue already linked to target issue via specified li
• Title is required
• Issue ${issueReference} is not in current project
• Invalid issue id/number
• Not eligible for multi-value

AI-assisted analysis of theonedev/onedev@d44925c47c (2026-09-06). Data as JSON: /api/errors/70e7a317688304ba. Report an issue: GitHub.