Semgrep code analysis

Semgrep is a lightweight static analysis for many languages. Find bug variants with patterns that look like source code

Semgrep is a fast, open-source, static analysis tool that searches code, finds bugs, and enforces secure guardrails and coding standards. Semgrep supports 30+ languages and can run in an IDE, as a pre-commit check, and as part of CI/CD workflows.

Github Actions

Add this file to your .github/workflows folder.

semgrep_code_check.yml

# Name of this GitHub Actions workflow.
name: Semgrep

on:
  # Scan changed files in PRs (diff-aware scanning):
  pull_request: {}
  # Scan on-demand through GitHub Actions interface:
  workflow_dispatch: {}
  # Scan mainline branches and report all findings:
  push:
    branches: ["master", "main"]

jobs:
  semgrep_scan:
    name: semgrep/ci
    runs-on: ubuntu-latest
    container:
      # A Docker image with Semgrep installed. Do not change this.
      image: returntocorp/semgrep
    permissions:
      # required for all workflows
      security-events: write
      # only required for workflows in private repositories
      actions: read
      contents: read

    steps:
      # Fetch project source with GitHub Actions Checkout.
      - name: Checkout repository
        uses: actions/checkout@v3

      - name: Perform Semgrep Analysis
      # Change the './src' to the root directory you want to set for semgrep to scan.
        run: semgrep scan -q --sarif --config auto ./src > semgrep-results.sarif

      # Upload the results for the CodeQL GitHub app to annotate the code
      - name: Save SARIF results as artifact
        uses: actions/upload-artifact@v3
        with:
          name: semgrep-scan-results
          path: semgrep-results.sarif

      # Upload SARIF file generated in previous step
      - name: Upload SARIF result to the GitHub Security Dashboard
        uses: github/codeql-action/upload-sarif@v3
        with:
          sarif_file: semgrep-results.sarif
        if: always()

Output

The code check run generates a results file in sarif format, is an industry standard format for the output of static analysis tools.