worker: hide previous comments when a new commit is pushed

Author: pietroalbini

src/bin/server/mod.rs

@@ -14,4 +14,5 @@ pub struct QueueItem {
 pub enum QueueItemKind {
     GitHubStatus(rla::github::CommitStatusEvent),
     GitHubCheckRun(rla::github::CheckRunEvent),
+    GitHubPullRequest(rla::github::PullRequestEvent),
 }

src/bin/server/service.rs

@@ -100,6 +100,13 @@ impl RlaService {
 
                 QueueItemKind::GitHubCheckRun(payload)
             }
+            "pull_request" => match serde_json::from_slice(body) {
+                Ok(payload) => QueueItemKind::GitHubPullRequest(payload),
+                Err(err) => {
+                    error!("Failed to decode 'pull_request' webhook payload: {}", err);
+                    return reply(StatusCode::BAD_REQUEST, "Failed to decode payload\n");
+                }
+            },
             "issue_comment" => {
                 debug!("Ignoring 'issue_comment' event.");
                 return reply(StatusCode::OK, "Event ignored.\n");

src/bin/server/worker.rs

@@ -115,6 +115,7 @@ impl Worker {
                     return Ok(());
                 }
             },
+            QueueItemKind::GitHubPullRequest(ev) => return self.process_pr(ev),
         };
 
         span.record("build_id", &build_id);
@@ -325,6 +326,15 @@ impl Worker {
 
         Ok(())
     }
+
+    fn process_pr(&self, e: &rla::github::PullRequestEvent) -> rla::Result<()> {
+        // Hide all comments by the bot when a new commit is pushed.
+        if let rla::github::PullRequestAction::Synchronize = e.action {
+            self.github
+                .hide_own_comments(&e.repository.full_name, e.number)?;
+        }
+        Ok(())
+    }
 }
 
 /// Keeps track of the recently seen IDs for both the failed build reports and the learned jobs.

src/github.rs

@@ -122,6 +122,32 @@ pub struct Repository {
     pub full_name: String,
 }
 
+#[derive(Deserialize)]
+#[serde(rename_all = "snake_case")]
+pub enum PullRequestAction {
+    Opened,
+    Edited,
+    Closed,
+    Assigned,
+    Unassigned,
+    ReviewRequested,
+    ReviewRequestRemoved,
+    ReadyForReview,
+    Labeled,
+    Unlabeled,
+    Synchronize,
+    Locked,
+    Unlocked,
+    Reopened,
+}
+
+#[derive(Deserialize)]
+pub struct PullRequestEvent {
+    pub action: PullRequestAction,
+    pub number: u32,
+    pub repository: Repository,
+}
+
 #[derive(Deserialize)]
 struct GraphResponse<T> {
     data: T,
@@ -213,8 +239,7 @@ impl Client {
     }
 
     pub fn hide_own_comments(&self, repo: &str, pull_request_id: u32) -> Result<()> {
-        const QUERY: &str =
-            "query($owner: String!, $repo: String!, $pr: Int!, $cursor: String) {
+        const QUERY: &str = "query($owner: String!, $repo: String!, $pr: Int!, $cursor: String) {
                 repository(owner: $owner, name: $repo) {
                     pullRequest(number: $pr) {
                         comments(first: 100, after: $cursor) {