Automatic blog deployment with TravisCI

Hello! Today I will write about how to automate blog deployment usingTravisCIwith bash scripts.

When I first started writing blog using pelican my workflow look as follows:

1. I open one terminal window and go under output just for serving static files using python -m SimpleHTTPServer
2. Then I open another terminal and if I wanted to generate my changes in the post I have to do pelican content -s pelicanconf.py -t  pelican-clean-blog
3. After this I open my browser window and go to 127.0.0.1:8000 to see my changes
4. To publish content I push it to responsible branch

After some time, I know that there must be the way to automate such boring stuff. So I started looking around my pelican folder and I found Makefile.

This makefile is used to manage all these things that I am doing manually into bash script so it is perfect!

Let's look into content of makefile, what is worth seeing is command devserver:

devserver:
ifdef PORT
        $(BASEDIR)/develop_server.sh restart $(PORT)else$(BASEDIR)/develop_server.sh restart
endif

So whenever you specify $(PORT) or not the same command will be used: develop_server.sh restart. So what we have in restart?

elif[[$1=="restart"]];then
 shut_down
 start_up $port

and start_up:

 1 function start_up(){ 2 localport=$1 3 echo"Starting up Pelican and HTTP server" 4 shift 5 echo$PELICANOPTS 6 $PELICAN --debug --autoreload -r $INPUTDIR -o $OUTPUTDIR -s $CONFFILE$PELICANOPTS& 7 pelican_pid=$! 8 echo$pelican_pid> $PELICAN_PID 9 cd$OUTPUTDIR10 $PY -m pelican.server $port&11 srv_pid=$!12 echo$srv_pid> $SRV_PID13 cd$BASEDIR14   sleep 1
15 if ! alive $pelican_pid;then16 echo"Pelican didn't start. Is the Pelican package installed?"17 return 1
18 elif ! alive $srv_pid;then19 echo"The HTTP server didn't start. Is there another service using port"$port"?"20 return 1
21 fi22 echo'Pelican and HTTP server processes now running in background.'23 }

In line 6 is normal pelican command like:

pelican --debug --autoreload -r personal_blog/content -o personal_blog/output -s personal_blog/pelicanconf.py

Is is running pelican in debug mode with auto reload taking post content from personal_blog/content. It generate output to personal_blog/output with settings from personal_blog/pelicanconf.py.

After that script enters the $OUTPUTDIR and starts the pelican server by $PY -m pelican.server $port.

But what if I wanted to publish my work into GitHub Pages? There is command for that in Makefile

github: publish
       ghp-import -m "Generate Pelican site" -b $(GITHUB_PAGES_BRANCH)$(OUTPUTDIR)
       git push origin $(GITHUB_PAGES_BRANCH)

It is using ghp-import. Ghp-import is python application that allows pushing content to GitHub branches. Why is that important? The GitHub pages are organized in that way:

Table taken fromGitHub Pages help.

As you can see to publish content on GitHub Pages you have to push either to master and you can see is under krzysztofzuraw.github.io or to gh-pages and go to krzysztofzuraw.github.io/personal-blog. As I wanted building process of my blog to be automated I choose second option: on master I will have all settings and content that is be used to render HTML will be on gh-pages branch.

So to automate I need TravisCI. After connecting service to your GitHub account, let's enable it for given project:

And on the next screen enable repository for what you want to trigger Travis. After this click on wheel next to the name of the repo. In next page setup two environmental variables:

GH_TOKEN is your token generated from this page. Click there on Generate new token and in next screen make sure you add token description and scope for public_repo:

After generating token add it to Travis. The another variable in Travis TRAVIS_REPO_SLUG is in the form of username/project-name so in my case it was krzysztofzuraw/personal-blog. After setting up these variables add the following file .travis.yml to the main root of your pelican blog project with following content:

language:pythonbranches:only:-masterinstall:-pip install pelican-pip install ghp-import-pip install pelican_gistscript:-make publish github

It tells Travis to install pelican, ghp-import and pelican_gist (plugin for gists in pelican) and then it runs make publish github.

To make it work I need to change one thing in Makefile:

github: publish
        ghp-import -m "Generate Pelican site" -b $(GITHUB_PAGES_BRANCH)$(OUTPUTDIR)
        git push -fq https://${GH_TOKEN}@github.com/$(TRAVIS_REPO_SLUG).git $(GITHUB_PAGES_BRANCH)

The change is that I push to repo using GH_TOKEN not username so Travis is able to do it.

So right now when I push my commits to master branch the Travis starts building my blog!