Use file-type environment variables

.gitlab/ci/deploy.gitlab-ci.yml

@@ -11,7 +11,7 @@ prepare-deploy:
     DOKKU_PORT: 22
     DOKKU_VERSION: v0.31.2
     DOKKU_DEPLOY_BRANCH: chore/rework-deployment
-    SSH_PRIVATE_KEY: $DOKKU_SSH_PRIVATE_KEY
+    SSH_PRIVATE_KEY_FILE: $DOKKU_SSH_PRIVATE_KEY_FILE
   script:
     - dokku network:exists "$APP_NAME-network" \
       || dokku network:create "$APP_NAME-network"

.gitlab/ci/dokku.gitlab-ci.yml

@@ -12,7 +12,8 @@
   before_script:
     - chmod +x .gitlab/bin/gitlab_before_script.sh && bash .gitlab/bin/gitlab_before_script.sh
     - eval $(ssh-agent -s)
-    - ssh-add "$SSH_PRIVATE_KEY"
+    - chmod 400 "$SSH_PRIVATE_KEY_FILE"
+    - ssh-add "$SSH_PRIVATE_KEY_FILE"
     - mkdir -p "$HOME/.ssh" && chmod 700 "$HOME/.ssh"
     - echo -e "Host *\n\tStrictHostKeyChecking no\n\n" >> $HOME/.ssh/config"
     - dokku version