Accepting pull requests: the easy way

Recently I became a committer in the Apache CloudStack project. Last week when I was working with Rohit Yadav from ShapeBlue he showed me how he had automated the process with a Git alias. I really like it so I’ll share it here as well.

First of all, pull requests are created on Github.com. Rohit created a git alias called simply ‘pr’. This is how it looks like (for the impatient: copy/paste the one-liner below). The command below is for easy reading, it will print a syntax error.

[alias]
pr= "!apply_pr() { set -e; 
rm -f githubpr.patch; 
wget $1.patch -O githubpr.patch
--no-check-certificate; 
git am -s githubpr.patch; 
rm -f githubpr.patch; 
pr_num=$(echo $1 | sed 's/.*pull\\///'); 
git log -1 --pretty=%B > prmsg.txt; 
echo \"This closes #$pr_num\" >> 
prmsg.txt; git commit --amend -m \"$(cat prmsg.txt)\"; 
rm prmsg.txt; }; apply_pr"

Copy/paste this next two lines into your .gitconfig file (usually located in ‘~/.gitconfig’.):

[alias]
pr= "!apply_pr() { set -e; rm -f githubpr.patch; wget $1.patch -O githubpr.patch --no-check-certificate; git am -s githubpr.patch; rm -f githubpr.patch; pr_num=$(echo $1 | sed 's/.*pull\\///'); git log -1 --pretty=%B > prmsg.txt; echo \"This closes #$pr_num\" >> prmsg.txt; git commit --amend -m \"$(cat prmsg.txt)\"; rm prmsg.txt; }; apply_pr"

This alias allows you to do this:

git pr https://pull-request-url

It will then fetch the patch, extract the pull request number, adds a note that closes the pull request, finally commits all commits to your current branch. All you have to do is review and push.

Let’s demo this on a pull request I openend on the CloudStack documentation. Goes like this:

git pr https://github.com/apache/cloudstack-docs-rn/pull/21

--2015-05-24 19:22:54-- 
https://github.com/apache/cloudstack-docs-rn/pull/21.patch
Resolving github.com... 192.30.252.130
Connecting to github.com|192.30.252.130|:443... connected.
HTTP request sent, awaiting response... 302 Found
Location: https://patch-diff.githubusercontent.com/raw/apache/cloudstack-docs-rn/pull/21.patch [following]
--2015-05-24 19:22:54-- 
https://patch-diff.githubusercontent.com/raw/apache/cloudstack-docs-rn/pull/21.patch
Resolving patch-diff.githubusercontent.com... 192.30.252.130
Connecting to patch-diff.githubusercontent.com|192.30.252.130|:443... connected.
HTTP request sent, awaiting response... 200 OK
Cookie coming from patch-diff.githubusercontent.com attempted to set domain to github.com
Length: unspecified [text/plain]
Saving to: 'githubpr.patch'
githubpr.patch [ <=> ] 9.23K --.-KB/s in 0.002s
2015-05-24 19:22:55 (4.96 MB/s) - 'githubpr.patch' saved [9449]

Applying: add note on XenServer: we depend on pool HA these days
Applying: remove cached python classes and add ignore file for it
Applying: explicitly mention the undocumented timeout setting

[master 08e325d] explicitly mention the undocumented timeout setting
 Author: Remi Bergsma <[email protected]>
 Date: Sun May 24 08:28:43 2015 +0200
 3 files changed, 21 insertions(+), 3 deletions(-)

The pull request has 3 commits that are now committed to the current branch. Check the log:

git log

Isn’t that great? Now all you have to do is push it to a upstream repository.

Signed-off-by
This is achieved by adding the following to ‘.gitconfig’:

[format]
 signoff = true

Thanks Rohit for sharing!