From 326d1e9250336cc380b2026131349da976749976 Mon Sep 17 00:00:00 2001
From: Matt Cruz <matt.cruz@nasdaq.com>
Date: Thu, 5 Dec 2024 14:30:18 -0500
Subject: [PATCH] Move Postgres Replica command to separate file for better
 readability

---
 .github/workflows/prebuild_postgres_replica.yml |  9 ++++++++-
 .github/workflows/test.yml                      |  8 +++++++-
 docker/postgres_replica/cmd.sh                  |  9 +++++++++
 postgres_replica.dockerfile                     | 14 +++-----------
 4 files changed, 27 insertions(+), 13 deletions(-)
 create mode 100644 docker/postgres_replica/cmd.sh

diff --git a/.github/workflows/prebuild_postgres_replica.yml b/.github/workflows/prebuild_postgres_replica.yml
index f907cf1..bf7169a 100644
--- a/.github/workflows/prebuild_postgres_replica.yml
+++ b/.github/workflows/prebuild_postgres_replica.yml
@@ -4,6 +4,7 @@ on:
   pull_request:
     paths:
       - 'postgres_replica.dockerfile'
+      - 'docker/postgres_replica/cmd.sh'
 
 jobs:
   export_variables:
@@ -22,7 +23,13 @@ jobs:
 
     - name: Calculate SHA256 for postgres_replica.dockerfile
       id: calculate_replica_sha
-      run: echo "REPLICA_SHA=$(sha256sum postgres_replica.dockerfile | awk '{ print substr($1, 1, 12) }')" >> $GITHUB_OUTPUT
+      run: |
+        checksum () {
+          sha256sum $@ | awk '{print substr($1, 1, 12)}'
+        }
+        REPLICA_DOCKERFILE_SHA=$(checksum postgres_replica.dockerfile)
+        REPLICA_CMD_SHA=$(checksum docker/postgres_replica/cmd.sh)
+        echo "REPLICA_SHA=$(echo \"${REPLICA_DOCKERFILE_SHA}-${REPLICA_CMD_SHA}\" | checksum)" >> $GITHUB_OUTPUT
 
   prebuild_replica:
     needs: export_variables
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 41f69f3..24eab39 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -30,7 +30,13 @@ jobs:
 
     - name: Calculate SHA256 for postgres_replica.dockerfile
       id: calculate_replica_sha
-      run: echo "REPLICA_SHA=$(sha256sum postgres_replica.dockerfile | awk '{ print substr($1, 1, 12) }')" >> $GITHUB_OUTPUT
+      run: |
+        checksum () {
+          sha256sum $@ | awk '{print substr($1, 1, 12)}'
+        }
+        REPLICA_DOCKERFILE_SHA=$(checksum postgres_replica.dockerfile)
+        REPLICA_CMD_SHA=$(checksum docker/postgres_replica/cmd.sh)
+        echo "REPLICA_SHA=$(echo \"${REPLICA_DOCKERFILE_SHA}-${REPLICA_CMD_SHA}\" | checksum)" >> $GITHUB_OUTPUT
 
   rubocop:
     runs-on: ubuntu-latest
diff --git a/docker/postgres_replica/cmd.sh b/docker/postgres_replica/cmd.sh
new file mode 100644
index 0000000..3861c16
--- /dev/null
+++ b/docker/postgres_replica/cmd.sh
@@ -0,0 +1,9 @@
+until pg_basebackup --pgdata=/var/lib/postgresql/data -R --slot=$PRIMARY_REPLICATION_SLOT --host=$PRIMARY_DATABASE_HOST --port=$PRIMARY_DATABASE_PORT
+do
+  echo 'Waiting for primary to connect...'
+  sleep 1s
+done
+
+echo 'Backup done, starting replica...'
+chmod 0700 /var/lib/postgresql/data
+postgres
diff --git a/postgres_replica.dockerfile b/postgres_replica.dockerfile
index 7b6975e..b5c5135 100644
--- a/postgres_replica.dockerfile
+++ b/postgres_replica.dockerfile
@@ -4,20 +4,12 @@ ENV PRIMARY_DATABASE_HOST=localhost
 ENV PRIMARY_DATABASE_PORT=5432
 ENV PRIMARY_REPLICATION_SLOT=replication_slot
 
-USER root
-RUN printf '' > cmd.sh
 
-RUN echo 'until pg_basebackup --pgdata=/var/lib/postgresql/data -R --slot=$PRIMARY_REPLICATION_SLOT --host=$PRIMARY_DATABASE_HOST --port=$PRIMARY_DATABASE_PORT' >> cmd.sh
-RUN echo 'do' >> cmd.sh
-RUN echo "echo 'Waiting for primary to connect...'" >> cmd.sh
-RUN echo 'sleep 1s' >> cmd.sh
-RUN echo 'done' >> cmd.sh
-RUN echo "echo 'Backup done, starting replica...'" >> cmd.sh
-RUN echo 'chmod 0700 /var/lib/postgresql/data' >> cmd.sh
-RUN echo 'postgres' >> cmd.sh
+COPY docker/postgres_replica/cmd.sh cmd.sh
 
+USER root
 RUN chown -R postgres:postgres cmd.sh
 USER postgres
-RUN chmod u+rwx cmd.sh
+RUN chmod u+x cmd.sh
 
 CMD [ "./cmd.sh" ]