From 1e088a99c482ea79abb5fc65ae468b4de7023ecb Mon Sep 17 00:00:00 2001
From: Emterry <emma.terry@digital.justice.gov.uk>
Date: Thu, 29 Feb 2024 16:28:32 +0000
Subject: [PATCH] add changelog

---
 .github/workflows/build.yml | 23 +++++++++++++++++++++++
 CHANGELOG.md                |  0
 2 files changed, 23 insertions(+)
 create mode 100644 CHANGELOG.md

diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 3b69174..caffb3f 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -28,3 +28,26 @@ jobs:
         with:
           context: .
           push: false
+
+  preflight-checks:
+    name: Preflight Checks
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        id: checkout
+        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
+      
+      - name: Check CHANGELOG Updates
+        id: check_changelog_updates
+        env:
+          GH_TOKEN: ${{ github.token }}
+        run: |
+          mainSha=$(gh api --method GET /repos/"${GITHUB_REPOSITORY}"/contents/CHANGELOG.md --field ref="main" | jq -r '.sha')
+          branchSha=$(gh api --method GET /repos/"${GITHUB_REPOSITORY}"/contents/CHANGELOG.md --field ref="${GITHUB_HEAD_REF}" | jq -r '.sha')
+
+          if [[ "${mainSha}" == "${branchSha}" ]]; then
+            echo "CHANGELOG.md matches main branch, needs to be updated"
+            exit 1
+          elif [[ "${mainSha}" != "${branchSha}" ]]; then
+            echo "CHANGELOG.md does not match main branch, does not need to be updated"
+          fi
\ No newline at end of file
diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 0000000..e69de29