Gerrit Code Review with GitHub plugin

Luca@gerritforge.comhttp://www.gerritforge.comTwitter: @gitenterprise

GitHub plugin for …

Luca Milanesio

GerritForge

gerritGerrit Code Review

Platinum Sponsor

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About Luca

Luca MilanesioCo-founder of GerritForge

over 20 years of experience in Agile Development SCM and ALM worldwide

Contributor to Jenkins since 2007 (and previously Hudson)

Git SCM mentor for the Enterprise since 2009

Contributor to Gerrit Code Review community since 2011

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About GerritForge

Founded in 2009 in London UKMission: Agile EnterpriseProducts:

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Agenda Fork+Pull request or Change review ? People says … My experience say … Plugging two worlds together echo "github" | sed -e "s/git/gerrit/" Pull requests and Repo replication What do YOU think ?

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Two divided review worlds

BRANCH+

PULL REQUEST

CHECKOUT+

AMEND

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Fork + Pull request

GitHub BitBucket GitLab Gitorious + others …

> 10M repositories > 4M users SourceRepo

mastera1c 2df f9a

fork

masterdec 6fa 7a1

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Change review (rebase example)

Gerrit GitBlit + others?

SourceRepo

mastera1c 2df 7a1

dec 6fa 7a1 changes/27/1627/*

amend amend

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Two worlds at a glance

1. BRANCH

2. SCORE THE

BRANCH

3. MERGE ALL

COMMITs in

BRANCH

1. CHECKOUT

2. SCORE THE

COMMIT

3. MERGE ONLY

the REVIEWED

COMMIT

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WHAT PEOPLE SAY ?

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There are two fundamental problems with single-patch review systems:1. They encourage lumping at-best-weakly-related

changes together.2. They encourage you to hide your history.

[http://bit.ly/1hhQkcA]

The pull-request system looks like an incredible easy way to contribute to any project hosted on Github [but] doing any proper and useful contribution to a software is never done right the first time. But as a software maintainer you'll end up with pull-request you'll never get finished unless you wrap things up yourself.

[http://bit.ly/1o7HIb6]

A big advantage in Github's favor is the number of developers that are familiar with it compared to Gerrit.

Gerrit can be popular with Git power-users, but friction-free use of it requires intermediate or advanced git knowledge, and tolerance of a steep learning curve.

[http://bit.ly/1cJV8IJ]

I have no problem with people using github as a hosting site, but in order for *me* to pull from github, you need to(a) make a real pull request […]: real explanation,

proper email addresses, proper shortlog, and proper diffstat.

(b) since github identities are random, I expect the pull request to be a signed tag

[http://bit.ly/1iONQ4L]

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MY OWN (OpenSource +

Enterprise)

[humble] EXPERIENCE …

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Review modelDO NOT make git bisect + git cherry-pick

uselessDO NOT throw commits over the fence

(e.g. “I’ve made the pull request, now it’s up to you”)

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Governance

DEFINE rules for your projectTRUST your identities and roles

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Social engagement

MAKE your project visible MAKE collaboration easy and fun

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Growth

PLAN for collaboration model to scaleAVOID explosion of forks and pending pull-

requests

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Can we take both worlds ?

+ = ?

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GitHub plugin for Gerrit Code Review

https://gerrit-review.googlesource.com/#/admin/projects/plugins/github

1. Imports Pull Requests Gerrit Changes / Topics2. Reuses GitHub identity using Gerrit auth rules3. Replication: keeps presence on http://github.com 4. Prevents explosion of unmanaged forks 5. Avoid GitHub spamming one-email-per-change

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Gerrit and GitHub? Who is ever gonna use it?

June 2014 Statistics

select count(*) from accounts = 1664 usersselect count(*) from changes = 3654 changesselect count(*) from patch_sets = 4720 patch-setsfind . -name '*.git' | wc –l = 5022 repositoriesdu -s -h git = 140 GBytes

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THIS IS COOL !

How can use it ?

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SPEEDY WAY

http://GerritHub.io/login

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DEMO TIME

[http://www.youtube.com/watch?v=jeWTvDad6VM]

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HACKY WAY

Build the plugin from source

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Step#1 - GitHub OAuth 2.0 application keyshttps://github.com/settings/applications/new

Your server URL (hostname / port Gerrit will listen to)

OAuth 2.0 callback URL isYour server URL + /oauth

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Step#2 – Get OAuth Client-Id / CLient-Secret

GitHub OAuth 2.0 credentials for Gerrit integration

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Step#3 – Download Gerrit 2.10 (master)

http://ci.gerritforge.com/job/Gerrit-master

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Step#4 – build GitHub plugin

git clone https://gerrit.googlesource.com/plugins/github && cd github mvn install[…][INFO] ------------------------------------------------------------------------[INFO] BUILD SUCCESS[INFO] ------------------------------------------------------------------------[INFO] Total time: 7.755s[INFO] Finished at: Sat Mar 15 19:16:23 GMT 2014[INFO] Final Memory: 57M/449M[INFO] ------------------------------------------------------------------------

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Step#5 – install OAuth filter and GitHub plugin> export GERRIT_SITE=/var/gerrit

> mkdir –p $GERRIT_SITE/lib > cp github-oauth/target/github-oauth*.jar $GERRIT_SITE/lib

> mkdir –p $GERRIT_SITE/plugins > cp github-plugin/target/github-plugin*.jar $GERRIT_SITE/plugins

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Step#6 – Gerrit setup + replication + singleusergroup> cd $GERRIT_SITE && java –jar release.war init –d $GERRIT_SITE*** Gerrit Code Review 2.9-rc1-779-g90fac34-dirty*** […]*** User Authentication*** Authentication method ? HTTPGet username from custom HTTP header ? YUsername HTTP header ? GITHUB_USER

*** Plugins*** Install plugin singleusergroup version v2.9-rc2-536-g79393b2 [y/N]? yInstall plugin replication version v2.9-rc2-536-g79393b2 [y/N]? y

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Step#7 – Configure GitHub integration

[…]

*** GitHub Integration*** GitHub URL ? https://github.comUse GitHub for Gerrit login ? Y ClientId ? 732819a7b9c9d9a98 ClientSecret ? 6271627a6a7s6s718173642718a9bcacdHTTP Authentication Header [GITHUB_USER]:

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Replay presentation: http://slideshare.net/lucamilanesio

Sign-in: http://gerrithub.io/login

Gerrit book: http://gerrithub.io/book

Learn more about

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