environment changes in yaml

.gitlab-ci.yml

-stages:
+#stages:
 # - deploy
-  - build
+#  - build
 #test_app:
-build_app:
- image: python:3.6
+#build_app:
+# image: python:3.6
 # stage: test
- stage: build
+# stage: build
 
- before_script:
- - python3 -V
- - ls -ltr
- - python3 -m venv venv
- - python3 -m venv python3-virtualenv
- - source python3-virtualenv/bin/activate
- - pwd
- - whoami
- script:
- - pip install Flask
- - echo $PATH
+# before_script:
+# - python3 -V
+# - ls -ltr
+# - python3 -m venv venv
+# - python3 -m venv python3-virtualenv
+# - source python3-virtualenv/bin/activate
+# - pwd
+# - whoami
+# script:
+# - pip install Flask
+# - echo $PATH
 # - /usr/bin/find / -name systemctl
 # - export FLASK_APP=hello.py
 # - export FLASK_ENV=development
@@ -31,17 +31,50 @@ build_app:
 # - sudo systemctl start python.service
 # - sudo systemctl start prod.service
 # - sudo  systemctl status python.service
- - |
-        if [[ $CI_COMMIT_REF_NAME == master ]]; then
-            echo "it's a prod server"
-            sudo systemctl start prod.service
+# - |
+ #       if [[ $CI_COMMIT_REF_NAME == master ]]; then
+  #          echo "it's a prod server"
+   #         sudo systemctl start prod.service
        # elif [[ $CI_COMMIT_REF_NAME == dev ]]; then
-        else
-            echo "it's a dev server"
-            sudo systemctl start python.service
-        fi
+    #    else
+     #       echo "it's a dev server"
+      #      sudo systemctl start python.service
+      #  fi
 # environment:
  #  name: staging
   # url : http://localhost/test
- tags:
- - ci 
+build_app:
+  image: python:3.6
+
+before_script:
+   - python3 -V
+   - ls -ltr
+   - python3 -m venv venv
+   - python3 -m venv python3-virtualenv
+   - source python3-virtualenv/bin/activate
+   - pwd
+   - whoami
+
+stages:
+   - production
+   - development
+     
+production:
+  stage: production
+  script:
+   - pip install Flask
+   - sudo systemctl start prod.service
+  only:
+   - dev
+
+development:
+  stage: development
+  script:
+   - pip install Flask
+ #  - echo $PATH
+   - echo "deploying to staging server"
+   - sudo systemctl start python.service
+  only:
+   - master
+tags:
+  - ci