CheckPullRequestContributionRules.java

package org.hibernate.infra.bot;

import java.io.IOException;
import java.util.ArrayList;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.Set;
import java.util.regex.Pattern;
import jakarta.inject.Inject;

import org.hibernate.infra.bot.check.Check;
import org.hibernate.infra.bot.check.CheckRunContext;
import org.hibernate.infra.bot.check.CheckRunOutput;
import org.hibernate.infra.bot.check.CheckRunRule;
import org.hibernate.infra.bot.config.DeploymentConfig;
import org.hibernate.infra.bot.config.RepositoryConfig;
import org.hibernate.infra.bot.util.CommitMessages;

import org.jboss.logging.Logger;

import io.quarkiverse.githubapp.ConfigFile;
import io.quarkiverse.githubapp.event.CheckRun;
import io.quarkiverse.githubapp.event.CheckSuite;
import io.quarkiverse.githubapp.event.PullRequest;
import org.kohsuke.github.GHEventPayload;
import org.kohsuke.github.GHIssueComment;
import org.kohsuke.github.GHIssueState;
import org.kohsuke.github.GHPullRequest;
import org.kohsuke.github.GHPullRequestCommitDetail;
import org.kohsuke.github.GHRepository;

public class CheckPullRequestContributionRules {

	private static final Logger LOG = Logger.getLogger( CheckPullRequestContributionRules.class );

	private static final Pattern SPACE_PATTERN = Pattern.compile( "\\s+" );

	private static final String COMMENT_INTRO_PASSED = """
			Thanks for your pull request!

			This pull request appears to follow the contribution rules.""";
	private static final String COMMENT_INTRO_FAILED = """
			Thanks for your pull request!

			This pull request does not follow the contribution rules. Could you have a look?
			""";
	private static final String COMMENT_FOOTER = "\n\n› This message was automatically generated.";

	@Inject
	DeploymentConfig deploymentConfig;

	void pullRequestChanged(
			@PullRequest.Opened @PullRequest.Reopened @PullRequest.Edited @PullRequest.Synchronize
					GHEventPayload.PullRequest payload,
			@ConfigFile("hibernate-github-bot.yml") RepositoryConfig repositoryConfig) throws IOException {
		checkPullRequestContributionRules( payload.getRepository(), repositoryConfig,
				payload.getPullRequest()
		);
	}

	void checkRunRequested(@CheckRun.Rerequested GHEventPayload.CheckRun payload,
			@ConfigFile("hibernate-github-bot.yml") RepositoryConfig repositoryConfig) throws IOException {
		for ( GHPullRequest pullRequest : payload.getCheckRun().getPullRequests() ) {
			checkPullRequestContributionRules( payload.getRepository(), repositoryConfig, pullRequest );
		}
	}

	void checkSuiteRequested(@CheckSuite.Requested @CheckSuite.Rerequested GHEventPayload.CheckSuite payload,
			@ConfigFile("hibernate-github-bot.yml") RepositoryConfig repositoryConfig) throws IOException {
		for ( GHPullRequest pullRequest : payload.getCheckSuite().getPullRequests() ) {
			checkPullRequestContributionRules( payload.getRepository(), repositoryConfig, pullRequest );
		}
	}

	private void checkPullRequestContributionRules(GHRepository repository, RepositoryConfig repositoryConfig,
			GHPullRequest pullRequest)
			throws IOException {
		if ( !shouldCheck( repository, pullRequest ) ) {
			return;
		}

		CheckRunContext context = new CheckRunContext( deploymentConfig, repository, repositoryConfig, pullRequest );
		List<Check> checks = createChecks( repositoryConfig );
		List<CheckRunOutput> outputs = new ArrayList<>();
		for ( Check check : checks ) {
			outputs.add( Check.run( context, check ) );
		}

		boolean passed = outputs.stream().allMatch( CheckRunOutput::passed );
		GHIssueComment existingComment = findExistingComment( pullRequest );
		// Avoid creating noisy comments for no reason, in particular if checks passed
		// or if the pull request was already closed.
		if ( existingComment == null && ( passed || GHIssueState.CLOSED.equals( pullRequest.getState() ) ) ) {
			return;
		}

		StringBuilder message = new StringBuilder( passed ? COMMENT_INTRO_PASSED : COMMENT_INTRO_FAILED );
		outputs.forEach( output -> output.appendFailingRules( message ) );
		message.append( COMMENT_FOOTER );

		if ( !deploymentConfig.isDryRun() ) {
			if ( existingComment == null ) {
				pullRequest.comment( message.toString() );
			}
			else {
				existingComment.update( message.toString() );
			}
		}
		else {
			LOG.info( "Pull request #" + pullRequest.getNumber() + " - Add comment " + message.toString() );
		}
	}

	// GitHub sometimes mentions pull requests in the payload that are definitely not related to the changes,
	// such as very old pull requests on the branch that just got updated,
	// or pull requests on different repositories.
	// We have to ignore those, otherwise we'll end up creating comments on old pull requests.
	private boolean shouldCheck(GHRepository repository, GHPullRequest pullRequest) {
		return !GHIssueState.CLOSED.equals( pullRequest.getState() )
				&& repository.getId() == pullRequest.getBase().getRepository().getId();
	}

	private GHIssueComment findExistingComment(GHPullRequest pullRequest) throws IOException {
		for ( GHIssueComment comment : pullRequest.listComments() ) {
			if ( comment.getBody().startsWith( COMMENT_INTRO_PASSED )
					|| comment.getBody().startsWith( COMMENT_INTRO_FAILED ) ) {
				return comment;
			}
		}
		return null;
	}

	private List<Check> createChecks(RepositoryConfig repositoryConfig) {
		List<Check> checks = new ArrayList<>();
		checks.add( new TitleCheck() );

		if ( repositoryConfig != null && repositoryConfig.jira != null ) {
			final boolean checkMentions = repositoryConfig.jira.getInsertLinksInPullRequests().isEmpty()
					|| repositoryConfig.jira.getInsertLinksInPullRequests().get().equals( Boolean.FALSE );
			repositoryConfig.jira.getIssueKeyPattern()
					.ifPresent( issueKeyPattern -> checks.add( new JiraIssuesCheck( issueKeyPattern, checkMentions ) ) );
		}

		return checks;
	}

	static class TitleCheck extends Check {

		TitleCheck() {
			super( "Contribution — Title" );
		}

		@Override
		public void perform(CheckRunContext context, CheckRunOutput output) {
			String title = context.pullRequest.getTitle();

			output.rule( "The pull request title should contain at least 2 words to describe the change properly" )
					.result( title != null && SPACE_PATTERN.split( title.trim() ).length >= 2 );
			output.rule( "The pull request title should not end with an ellipsis (make sure the title is complete)" )
					.result( title == null || !title.endsWith( "…" ) );
		}
	}

	static class JiraIssuesCheck extends Check {

		private final Pattern issueKeyPattern;

		private final boolean checkMentions;

		JiraIssuesCheck(Pattern issueKeyPattern, boolean checkMentions) {
			super( "Contribution — JIRA issues" );
			this.issueKeyPattern = issueKeyPattern;
			this.checkMentions = checkMentions;
		}

		@Override
		public void perform(CheckRunContext context, CheckRunOutput output) throws IOException {
			String title = context.pullRequest.getTitle();
			String body = context.pullRequest.getBody();

			Set<String> issueKeys = new LinkedHashSet<>();
			Set<String> commitsWithMessageNotStartingWithIssueKey = new LinkedHashSet<>();
			for ( GHPullRequestCommitDetail commitDetails : context.pullRequest.listCommits() ) {
				GHPullRequestCommitDetail.Commit commit = commitDetails.getCommit();
				List<String> commitIssueKeys = CommitMessages.extractIssueKeys( issueKeyPattern, commit.getMessage() );
				if ( commitIssueKeys.isEmpty() ) {
					commitsWithMessageNotStartingWithIssueKey.add( commitDetails.getSha() );
				}
				else {
					issueKeys.addAll( commitIssueKeys );
				}
			}

			CheckRunRule commitRule =
					output.rule( "All commit messages should start with a JIRA issue key matching pattern `"
							+ issueKeyPattern + "`" );
			if ( commitsWithMessageNotStartingWithIssueKey.isEmpty() ) {
				commitRule.passed();
			}
			else {
				commitRule.failed( "Offending commits: " + commitsWithMessageNotStartingWithIssueKey );
			}

			if ( checkMentions ) {
				// We only need to check mentions if automatic body editing is disabled
				CheckRunRule pullRequestRule = output.rule(
						"The PR title or body should list the keys of all JIRA issues mentioned in the commits");
				List<String> issueKeysNotMentionedInPullRequest = issueKeys.stream()
						.filter(issueKey -> (title == null || !title.contains(issueKey))
								&& (body == null || !body.contains(issueKey)))
						.toList();
				if (issueKeysNotMentionedInPullRequest.isEmpty()) {
					pullRequestRule.passed();
				} else {
					pullRequestRule.failed("Issue keys mentioned in commits but missing from the PR title or body: " + issueKeysNotMentionedInPullRequest);
				}
			}
		}
	}

}