Dr Jekyll and Mister --safe Github jekyll, github, bash, git

March 29, 2013

Setup a blog with Jekyll on Github. Back. Again.
Solution : static site … generated dynamically
Step by Step :
One for all
Aliasing
In so quick & dirty way : a little bash script

Setup a blog with Jekyll on Github. Back. Again.

So you’ve got a nice simple Github pages. Missing some tag ? No problem, check the Jekyll plugins directory, tape one and install it. jekyll serve --port 80 locally (i’m on Jekyll 1 prerelease) and all it’s fine ! Simple blog, with simple tag management.

One git push origin remote and … c’est le bordel, as we says here … First check my code … but nothing seems wrong. Monkey-patch the plugin … nothing wrong again …

Digging Google : Github run his github page with -- safe : no plugins are allowed to run on Github page !!

Solution : static site … generated dynamically

Finally have found the solution with http://edhedges.com/blog/2012/07/30/jekyll-with-plugins-hosted-on-github-pages/ : keep Git with 2 different structures,

the master branch : containing only the static site (inside the _site directory of your Jekyll installation)
a dev branch : containing the full Jekyll site, where i launch the jekyll server for generate the statics pages.

Step by Step :

create a new branch

      git checkout -b dev

work on this branch only (create another branch from this one for testing new features, or just create some new posts), and use git here (commit, merge from new features, …)
when you want to publish, run jekyll server for generating the statics files in _site

      jekyll build

get a reference id for the tree (_site) : this pointer contain only a reference to the _site tree.

      git commit-tree dev^{tree}:_site -m 'message'
      > COMMIT_ID

and check your log

      git lg COMMIT_ID

now, update the master branch for pointing only to this tree object :

      git update-ref refs/heads/master COMMIT_ID

go to the master branch

      git checkout master

and push it to github (with -f option because our master doesn’t have any parent)

      git push -f origin master

And that’s it !

One for all

Ok, do all of this in just one step from the dev branch (after running jekyll) :

    git update-ref refs/heads/master $(echo 'Add commit message here!' | git commit-tree dev^{tree}:_site -p $(cat .git/refs/heads/master))

Aliasing

Easing the hacker life :)

So, in [alias] section of .gitconfig

    devtree = "!sh -c 'git update-ref refs/heads/master $(echo \"Transfert\" | git commit-tree dev^{tree}:_site -p $(cat .git/refs/heads/master))'"

    ### in quick and dirty way, a shell alias : 

    alias trf="jekyll build && git add . && git commit -m 'post : upd' && git devtree && git co master && git push origin master && git co dev"

Now, after commiting my work, I have just to launch a trf command for publishing on Github :)

In so quick & dirty way : a little bash script

Feel free to comment / improve it ! In short, use your dev for working and master only for pushing to Github. Gist code

    #!/bin/bash  


    echo "------- Transfer statics pages to Github (make sure jekyll build ok, and git branch dev commited) ---"

    current_branch=$(git branch | grep '*' | cut -c 3-)
    echo -e "-- \033[1;33mGit\033[0m    : Current branch :\033[0;31m $current_branch\033[0m"

    if [ $current_branch != "dev" ]; then
      echo -e "-- \033[0;31mERROR : Branch must be dev \033[0m"
      echo "------- Finished"
      exit 0;
    fi

    echo -e "-- \033[0;32mJekyll\033[0m : Build"
    jekyll build

    echo -e "-- \033[0;33mGit\033[0m    : add ."
    git add .

    echo -e "-- \033[0;34mUSER\033[0m   : enter the commit message for dev branch : "
    read dev_commit_message

    echo -e "-- \033[0;33mGit\033[0m    : commit dev "
    git commit -m "$dev_commit_message"


    master_commit_id=$(cat .git/refs/heads/master)
    echo -e "-- \033[0;33mGit\033[0m    : get the last COMMIT_ID of master branch :\033[0;31m ${master_commit_id:0:7}\033[0m"



    commit_tree_id=$(git commit-tree dev^{tree}:_site -p $master_commit_id -m '$dev_commit_message')
    echo -e "-- \033[0;33mGit\033[0m    : commit-tree _site, id :\033[0;31m ${commit_tree_id:0:7} \033[0m"

    new_master_commit_id=$(git update-ref refs/heads/master $commit_tree_id)
    echo -e "-- \033[0;33mGit\033[0m    : update-ref, new master id  : \033[0;31m ${new_master_commit_id:0:7} \033[0m"


    echo -e "-- \033[0;33mGit\033[0m    : checkout master"
    git checkout master

    echo -e "-- \033[0;33mGit\033[0m    : push origin master to github"
    git push origin master 

    echo -e "-- \033[0;33mGit\033[0m    : checkout dev"
    git checkout dev 

    echo "------- Finished "

Don’t hesitate to improve it !