From 9888ba3d4e7f941c06abca90a8e94f6336972f40 Mon Sep 17 00:00:00 2001
From: Athanasios Voutsadakis
 <athanasios.voutsadakis@digital.cabinet-office.gov.uk>
Date: Wed, 28 Mar 2018 17:19:02 +0100
Subject: [PATCH 1/3] Add http health-check for the api app

Also rename the 'elb' argument to 'simple' to be more descriptive.

The healthcheck is going to issue requests to `/_status?simple=true`
just to check that gunicorn is up and running - we don't need to go all
the way to the database, as this would have adverse impact when api is
under load.
---
 app/status/healthcheck.py | 2 +-
 manifest-api-base.yml     | 2 ++
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/app/status/healthcheck.py b/app/status/healthcheck.py
index e704e6b73..da305c9e2 100644
--- a/app/status/healthcheck.py
+++ b/app/status/healthcheck.py
@@ -11,7 +11,7 @@ status = Blueprint('status', __name__)
 
 @status.route('/_status', methods=['GET', 'POST'])
 def show_status():
-    if request.args.get('elb', None):
+    if request.args.get('simple', None):
         return jsonify(status="ok"), 200
     else:
         return jsonify(
diff --git a/manifest-api-base.yml b/manifest-api-base.yml
index e8197575f..bc043e351 100644
--- a/manifest-api-base.yml
+++ b/manifest-api-base.yml
@@ -51,6 +51,8 @@ memory: 1G
 
 applications:
   - name: notify-api
+    health-check-type: http
+    health-check-http-endpoint: /_status?simple=true
 
   - name: notify-api-db-migration
     command: sleep infinity

From 23cfe73c488072968bd501838021df4d6d2f519b Mon Sep 17 00:00:00 2001
From: Athanasios Voutsadakis
 <athanasios.voutsadakis@digital.cabinet-office.gov.uk>
Date: Wed, 11 Apr 2018 15:01:45 +0100
Subject: [PATCH 2/3] Add 5 second sleep before stopping old api instances

This is to allow the new instances to start responding to the http
healthchecks and start serving traffic.
---
 Makefile | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Makefile b/Makefile
index ebf56145a..57585e43b 100644
--- a/Makefile
+++ b/Makefile
@@ -208,6 +208,7 @@ cf-deploy: ## Deploys the app to Cloud Foundry
 	cf rename ${CF_APP} ${CF_APP}-rollback
 	cf push ${CF_APP} -f <(make -s generate-manifest)
 	cf scale -i $$(cf curl /v2/apps/$$(cf app --guid ${CF_APP}-rollback) | jq -r ".entity.instances" 2>/dev/null || echo "1") ${CF_APP}
+	if [ "${CF_APP}" == "notify-api" ]; then sleep 5; fi
 	cf stop ${CF_APP}-rollback
 	# sleep for 10 seconds to try and make sure that all worker threads (either web api or celery) have finished before we delete
 	# when we delete the DB is unbound from the app, which can cause "permission denied for relation" psycopg2 errors.

From 0766e680998bff16db1ec2a8a60ebb19a8ff6053 Mon Sep 17 00:00:00 2001
From: Athanasios Voutsadakis
 <athanasios.voutsadakis@digital.cabinet-office.gov.uk>
Date: Wed, 11 Apr 2018 15:38:41 +0100
Subject: [PATCH 3/3] Revert "Add 5 second sleep before stopping old api
 instances"

This reverts commit 23cfe73c488072968bd501838021df4d6d2f519b.
---
 Makefile | 1 -
 1 file changed, 1 deletion(-)

diff --git a/Makefile b/Makefile
index 57585e43b..ebf56145a 100644
--- a/Makefile
+++ b/Makefile
@@ -208,7 +208,6 @@ cf-deploy: ## Deploys the app to Cloud Foundry
 	cf rename ${CF_APP} ${CF_APP}-rollback
 	cf push ${CF_APP} -f <(make -s generate-manifest)
 	cf scale -i $$(cf curl /v2/apps/$$(cf app --guid ${CF_APP}-rollback) | jq -r ".entity.instances" 2>/dev/null || echo "1") ${CF_APP}
-	if [ "${CF_APP}" == "notify-api" ]; then sleep 5; fi
 	cf stop ${CF_APP}-rollback
 	# sleep for 10 seconds to try and make sure that all worker threads (either web api or celery) have finished before we delete
 	# when we delete the DB is unbound from the app, which can cause "permission denied for relation" psycopg2 errors.