Add documentation on deployment.

Author: matthias_schaub

.travis.yml

@@ -39,21 +39,20 @@ script:
   - docker-compose run mapswipe_workers python -m unittest discover --verbose --start-directory tests/integration/
 
 after_success:
-  # Deploy to development server using Ansible
   # SSH setup to deploy to server after build.
   - apk add openssh-client
-  - eval "$(ssh-agent -s)"  #start the ssh agent
+  - eval "$(ssh-agent -s)"  # start the ssh agent
   - mkdir -p $HOME/.ssh
-  # - chmod 700 $HOME/.ssh
+  # Use config to define SSH connection variables (User, IdentityFile)
   - cp travis/ssh_config $HOME/.ssh/config
   - openssl aes-256-cbc -K $encrypted_c17fa81e6490_key -iv $encrypted_c17fa81e6490_iv -in travis/ssh-private-key.enc -out $HOME/.ssh/private-key -d
   - chmod 600 $HOME/.ssh/private-key
   - ssh-add $HOME/.ssh/private-key
   - chmod +x deploy.sh
 
 deploy:
+  # Deploy to server using Ansible
   provider: script
-  # Extent waiting time of Travis for deploy to to finish
   script: bash deploy.sh
   on:
     branch: dev

deploy.sh

@@ -1,8 +1,10 @@
 #!/bin/bash
-# Deploy to dev server.
+# Deploy to server.
 # This script is called by Travis.
 
 function bell() {
+  # Print regular to stdout, so that Travis will not abort due to time.
+  # travis_wait does not work with script deployment.
   while true; do
     echo -e "\a"
     sleep 60
@@ -12,4 +14,4 @@ bell &
 
 ansible-playbook -i ansible/inventory.yml ansible/playbook.yml
 
-exit $?
+exit $?  # Return exit code of last command

docs/source/contributing.md

@@ -34,3 +34,10 @@ From now on `black`, `flake8` and `isort` should run automatically whenever `git
 
 When running those tools manually please make sure the right version is used. The version can be looked up in `.pre-commit-config.yaml`.
 To update to newer version please make sure to change version numbers in `.pre-commit-config.yaml`, `.travis.yml` and `requirements.txt`.
+
+
+### Tips
+
+Ignore a hook: `SKIP=flake8 git commit -m "foo"`
+Mark in code that flake8 should ignore the line: `print()  # noqa`
+

docs/source/deployment_overview.md

@@ -16,3 +16,12 @@ MapSwipe utilizes a bunch of Google Cloud services:
 [Configuration](configuration.md) describes all needed configuration and credentials.
 
 [Installation](installation.md) describes step-by-step how to setup the backend for the first time.
+
+
+## Continuous deployment using Ansible and Travis
+
+Travis is setup to automatically deploy a new version of MapSwipe Back-End to the server once it run successfully.
+This is done by using Travis script deployment (https://docs.travis-ci.com/user/deployment/script/). Travis simply calls the `deploy.sh` script found at the root directory of MapSwipe Workers.
+To be able to connect to the MapSwipe server the Travis instance uses an encrypted SSH private key (Which can be found in the directory `travis/`).
+
+In the `deploy.sh` script an Ansible Playbook is run (https://docs.ansible.com/ansible/latest/index.html). Ansible is an automation tool which utilizes a SSH connection (`ansible/ansible.cfg`) to run commands defined in the Playbook (`ansible/playbook.yml`) on hosts defined in the Inventory (`ansible/inventory.yml`).