fix: posting canbench results from forked repos (#209)

Note that canbench didn't comment with the benchmark results in this PR.
Due to a quirk with Github actions, that will happen for subsequent PRs
once this is merged.

.github/workflows/ci.yml

@@ -76,11 +76,6 @@ jobs:
   benchmark:
     runs-on: ubuntu-latest
     needs: build
-    permissions:
-      # To allow writing comments to the PR in forked repositorites.
-      # See https://github.com/thollander/actions-comment-pull-request/issues/181
-      pull-requests: write
-
     env:
       PROJECT_DIR: .
     steps:
@@ -93,16 +88,13 @@ jobs:
           ref: main
           path: _canbench_main_branch
 
-      - name: Cache Cargo
-        uses: actions/cache@v2
+      - uses: actions/cache@v2
         with:
           path: |
             ~/.cargo/registry
             ~/.cargo/git
             target
-          key: ${{ matrix.build }}-cargo-${{ hashFiles('**/Cargo.lock') }}
-          restore-keys: |
-            ${{ matrix.build }}-cargo-
+          key: ${{ runner.os }}-cargo-${{ hashFiles('**/Cargo.lock') }}-1
 
       - name: Install Rust
         run: |
@@ -112,17 +104,25 @@ jobs:
 
       - name: Benchmark
         run: |
-          bash .github/workflows/canbench_ci_run_benchmark.sh $PROJECT_DIR
+          bash ./scripts/ci_run_benchmark.sh $PROJECT_DIR ${{ github.job }}
+
+      - uses: actions/upload-artifact@v4
+        with:
+          name: canbench_result_${{github.job}}
+          path: /tmp/canbench_result_${{ github.job }}
+
+      - name: Save PR number
+        run: |
+          echo ${{ github.event.number }} > /tmp/pr_number
 
-      - name: Post comment
-        uses: thollander/actions-comment-pull-request@v2
+      - uses: actions/upload-artifact@v4
         with:
-          filePath: /tmp/canbench_comment_message.txt
-          comment_tag: ${{ env.PROJECT_DIR }}
+          name: pr_number
+          path: /tmp/pr_number
 
       - name: Pass or fail
         run: |
-          bash .github/workflows/canbench_ci_post_run_benchmark.sh
+          bash ./scripts/ci_post_run_benchmark.sh
 
   checks-pass:
     # Always run this job!

.github/workflows/canbench_ci_download_artifacts.sh → scripts/ci_download_canbench_artifacts.sh

@@ -27,4 +27,3 @@ json_array+="]"
 # Output the benchmarks and PR number to be used by the next job.
 echo "matrix={\"benchmark\": $json_array}" >> "$GITHUB_OUTPUT"
 echo "pr_number=$(cat ./pr_number/pr_number)" >> "$GITHUB_OUTPUT"
-

.github/workflows/canbench_ci_run_benchmark.sh → scripts/ci_run_benchmark.sh

@@ -7,8 +7,11 @@ set -Eexuo pipefail
 # Path to run `canbench` from.
 CANISTER_PATH=$1
 
+# The name of the job in CI
+CANBENCH_JOB_NAME=$2
+
 # Must match the file specified in the github action.
-COMMENT_MESSAGE_PATH=/tmp/canbench_comment_message.txt
+COMMENT_MESSAGE_PATH=/tmp/canbench_result_${CANBENCH_JOB_NAME}
 
 # Github CI is expected to have the main branch checked out in this folder.
 MAIN_BRANCH_DIR=_canbench_main_branch
@@ -45,7 +48,7 @@ fi
 popd
 
 
-echo "# \`canbench\` 🏋" > $COMMENT_MESSAGE_PATH
+echo "# \`canbench\` 🏋 (dir: $CANISTER_PATH)" > "$COMMENT_MESSAGE_PATH"
 
 # Detect if there are performance changes relative to the main branch.
 if [ -f "$MAIN_BRANCH_RESULTS_FILE" ]; then
@@ -54,23 +57,15 @@ if [ -f "$MAIN_BRANCH_RESULTS_FILE" ]; then
 
   # Run canbench to compare result to main branch.
   pushd "$CANISTER_PATH"
-  set +e
-  canbench --less-verbose > $CANBENCH_OUTPUT
-  RES=$?
-  set -e
+  canbench --less-verbose > "$CANBENCH_OUTPUT"
   popd
 
-  if [ "$RES" -eq 0 ]; then
-    if grep -q "(regress\|(improved by" "${CANBENCH_OUTPUT}"; then
-      echo "**Significant performance change detected! ⚠️**
-      " >> $COMMENT_MESSAGE_PATH;
-    else
-      echo "**No significant performance changes detected ✅**
-      " >> $COMMENT_MESSAGE_PATH
-    fi
+  if grep -q "(regress\|(improved by" "${CANBENCH_OUTPUT}"; then
+    echo "**Significant performance change detected! ⚠️**
+    " >> "$COMMENT_MESSAGE_PATH"
   else
-    echo "Failed to run \`canbench\` against main branch ⚠️
-    " >> $COMMENT_MESSAGE_PATH
+    echo "**No significant performance changes detected ✅**
+    " >> "$COMMENT_MESSAGE_PATH"
   fi
 fi
 
@@ -81,7 +76,7 @@ fi
   echo "\`\`\`"
   cat "$CANBENCH_OUTPUT"
   echo "\`\`\`"
-} >> $COMMENT_MESSAGE_PATH
+} >> "$COMMENT_MESSAGE_PATH"
 
 # Output the comment to stdout.
-cat $COMMENT_MESSAGE_PATH
+cat "$COMMENT_MESSAGE_PATH"