Merge branch '48004-db-initialize-migrate' into 'master'

Support db migration and initialization for Auto DevOps

Closes #48004

See merge request gitlab-org/gitlab-ce!21955

changelogs/unreleased/48004-db-initialize-migrate.yml

+---
+title: Support db migration and initialization for Auto DevOps
+merge_request: 21955
+author:
+type: added

doc/topics/autodevops/index.md

@@ -440,6 +440,30 @@ no longer be valid as soon as the deployment job finishes. This means that
 Kubernetes can run the application, but in case it should be restarted or
 executed somewhere else, it cannot be accessed again.
 
+> [Introduced][ce-21955] in GitLab 11.4
+
+Database initialization and migrations for PostgreSQL can be configured to run
+within the application pod by setting the project variables `DB_INITIALIZE` and
+`DB_MIGRATE` respectively.
+
+If present, `DB_INITIALIZE` will be run as a shell command within an application pod as a helm
+post-install hook. Note that this means that if any deploy succeeds,
+`DB_INITIALIZE` will not be processed thereafter.
+
+If present, `DB_MIGRATE` will be run as a shell command within an application pod as
+a helm pre-upgrade hook.
+
+For example, in a Rails application:
+
+* `DB_INITIALIZE` can be set to `cd /app && RAILS_ENV=production
+  bin/setup`
+* `DB_MIGRATE` can be set to `cd /app && RAILS_ENV=production bin/update`
+
+NOTE: **Note:**
+The `/app` path is the directory of your project inside the docker image
+as [configured by
+Herokuish](https://github.com/gliderlabs/herokuish#paths)
+
 > [Introduced][ce-19507] in GitLab 11.0.
 
 For internal and private projects a [GitLab Deploy Token](../../user/project/deploy_tokens/index.md###gitlab-deploy-token)
@@ -581,6 +605,8 @@ also be customized, and you can easily use a [custom buildpack](#custom-buildpac
 | `BUILDPACK_URL`              | The buildpack's full URL. It can point to either Git repositories or a tarball URL. For Git repositories, it is possible to point to a specific `ref`, for example `https://github.com/heroku/heroku-buildpack-ruby.git#v142` |
 | `SAST_CONFIDENCE_LEVEL`      | The minimum confidence level of security issues you want to be reported; `1` for Low, `2` for Medium, `3` for High; defaults to `3`.|
 | `DEP_SCAN_DISABLE_REMOTE_CHECKS` | Whether remote Dependency Scanning checks are disabled; defaults to `"false"`. Set to `"true"` to disable checks that send data to GitLab central servers. [Read more about remote checks](https://gitlab.com/gitlab-org/security-products/dependency-scanning#remote-checks).|
+| `DB_INITIALIZE`              | From GitLab 11.4, this variable can be used to specify the command to run to initialize the application's PostgreSQL database. It runs inside the application pod. |
+| `DB_MIGRATE`                 | From GitLab 11.4, this variable can be used to specify the command to run to migrate the application's PostgreSQL database. It runs inside the application pod. |
 | `STAGING_ENABLED`            | From GitLab 10.8, this variable can be used to define a [deploy policy for staging and production environments](#deploy-policy-for-staging-and-production-environments). |
 | `CANARY_ENABLED`             | From GitLab 11.0, this variable can be used to define a [deploy policy for canary environments](#deploy-policy-for-canary-environments). |
 | `INCREMENTAL_ROLLOUT_ENABLED`| From GitLab 10.8, this variable can be used to enable an [incremental rollout](#incremental-rollout-to-production) of your application for the production environment. |
@@ -834,4 +860,5 @@ curl --data "value=true" --header "PRIVATE-TOKEN: personal_access_token" https:/
 [postgresql]: https://www.postgresql.org/
 [Auto DevOps template]: https://gitlab.com/gitlab-org/gitlab-ce/blob/master/lib/gitlab/ci/templates/Auto-DevOps.gitlab-ci.yml
 [ee]: https://about.gitlab.com/pricing/
+[ce-21955]: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/21955
 [ce-19507]: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/19507

lib/gitlab/ci/templates/Auto-DevOps.gitlab-ci.yml

@@ -598,26 +598,59 @@ rollout 100%:
       secret_name=''
     fi
 
-    helm upgrade --install \
-      --wait \
-      --set service.enabled="$service_enabled" \
-      --set releaseOverride="$CI_ENVIRONMENT_SLUG" \
-      --set image.repository="$CI_APPLICATION_REPOSITORY" \
-      --set image.tag="$CI_APPLICATION_TAG" \
-      --set image.pullPolicy=IfNotPresent \
-      --set image.secrets[0].name="$secret_name" \
-      --set application.track="$track" \
-      --set application.database_url="$DATABASE_URL" \
-      --set service.url="$CI_ENVIRONMENT_URL" \
-      --set replicaCount="$replicas" \
-      --set postgresql.enabled="$postgres_enabled" \
-      --set postgresql.nameOverride="postgres" \
-      --set postgresql.postgresUser="$POSTGRES_USER" \
-      --set postgresql.postgresPassword="$POSTGRES_PASSWORD" \
-      --set postgresql.postgresDatabase="$POSTGRES_DB" \
-      --namespace="$KUBE_NAMESPACE" \
-      "$name" \
-      chart/
+    if [[ -n "$DB_INITIALIZE" && -z "$(helm ls -q "^$name$")" ]]; then
+      helm upgrade --install \
+        --wait \
+        --set service.enabled="$service_enabled" \
+        --set releaseOverride="$CI_ENVIRONMENT_SLUG" \
+        --set image.repository="$CI_APPLICATION_REPOSITORY" \
+        --set image.tag="$CI_APPLICATION_TAG" \
+        --set image.pullPolicy=IfNotPresent \
+        --set image.secrets[0].name="$secret_name" \
+        --set application.track="$track" \
+        --set application.database_url="$DATABASE_URL" \
+        --set service.url="$CI_ENVIRONMENT_URL" \
+        --set replicaCount="$replicas" \
+        --set postgresql.enabled="$postgres_enabled" \
+        --set postgresql.nameOverride="postgres" \
+        --set postgresql.postgresUser="$POSTGRES_USER" \
+        --set postgresql.postgresPassword="$POSTGRES_PASSWORD" \
+        --set postgresql.postgresDatabase="$POSTGRES_DB" \
+        --set application.initializeCommand="$DB_INITIALIZE" \
+        --namespace="$KUBE_NAMESPACE" \
+        "$name" \
+        chart/
+
+      helm upgrade --reuse-values \
+        --wait \
+        --set application.initializeCommand="" \
+        --set application.migrateCommand="$DB_MIGRATE" \
+        --namespace="$KUBE_NAMESPACE" \
+        "$name" \
+        chart/
+    else
+      helm upgrade --install \
+        --wait \
+        --set service.enabled="$service_enabled" \
+        --set releaseOverride="$CI_ENVIRONMENT_SLUG" \
+        --set image.repository="$CI_APPLICATION_REPOSITORY" \
+        --set image.tag="$CI_APPLICATION_TAG" \
+        --set image.pullPolicy=IfNotPresent \
+        --set image.secrets[0].name="$secret_name" \
+        --set application.track="$track" \
+        --set application.database_url="$DATABASE_URL" \
+        --set service.url="$CI_ENVIRONMENT_URL" \
+        --set replicaCount="$replicas" \
+        --set postgresql.enabled="$postgres_enabled" \
+        --set postgresql.nameOverride="postgres" \
+        --set postgresql.postgresUser="$POSTGRES_USER" \
+        --set postgresql.postgresPassword="$POSTGRES_PASSWORD" \
+        --set postgresql.postgresDatabase="$POSTGRES_DB" \
+        --set application.migrateCommand="$DB_MIGRATE" \
+        --namespace="$KUBE_NAMESPACE" \
+        "$name" \
+        chart/
+    fi
 
     kubectl rollout status -n "$KUBE_NAMESPACE" -w "deployment/$name"
   }