Plugin for sbt to "roll" – view and navigate – the Git commit history. This turns out to be very useful for live coding and training sessions. As of version 5 sbt-groll depends on sbt-git, i.e. a local Git installation can be used, but is not needed.

sbt-groll is a plugin for sbt 1.0.0 or higher. In order to install sbt, please refer to the sbt documentation. Please make sure that you are using a suitable version of sbt:

As sbt-groll is a plugin for sbt, it is installed like any other sbt plugin, that is by mere configuration: just add sbt-groll to your global or local plugin definition. Global plugins are defined in ~/.sbt/<sbt_version>/plugins/plugins.sbt and local plugins are defined in project/plugins.sbt in your project.

In order to add sbt-groll as a plugin, just add the below setting to the relevant plugin definition:

addSbtPlugin("de.heikoseeberger" % "sbt-groll" % "6.1.0")

After adding the sbt-groll plugin like this, you should either start sbt or, if it was already started, reload the current session by executing the reload command. If everything worked, you should have the new groll command available.

sbt-groll adds the groll command that provides various ways to view and navigate the Git history. Of course this means, that you can only use sbt-groll for projects which are using Git as version control system.

If you navigate the Git history, i.e. move to some commit, sbt-groll reloads the sbt session if the build definition changes, i.e. any .sbt file in the project root directory or any .scala or .sbt file in the project/ directory.

In order to use sbt-groll, just execute groll <arg_or_opt> in an sbt session, giving one of the arguments or options described below. Here are two examples:

> groll show
[info] == 0bf1f60 Exercise: Connect to a remote system> groll move=bc1ac93
> groll head
[info] >> b97ef22 Exercise: HTTP server

sbt-groll can be configured by the following settings:

• grollConfigFile: java.io.File – the configuration file for sbt-groll; "~/.sbt-groll.conf" by default
• grollHistoryRef: String – the ref (commit id, branch or tag) used for the Git history; "main" by default
• grollWorkingBranch: String – the working branch used by sbt-groll; "groll" by default

The groll command must be followed by one of the following arguments or options:

• show – shows the current commit id and message, if current commit is in history
• list – shows the full commit history
• next – moves to the next commit
• prev – moves to the previous commit
• head – moves to the head of the commit history
• initial – moves to a commit with a message containing "groll:initial" or starting with "Initial state" or with a tag "groll-initial"
• move=<commit> – moves to the given commit
• push=<branch> – pushes the current commit via HTTPS to the "origin-https" remote repository (needs to be defined!) under the given branch
• help - shows this help info.

Contributions via GitHub pull requests are gladly accepted from their original author. Along with any pull requests, please state that the contribution is your original work and that you license the work to the project under the project's open source license. Whether or not you state this explicitly, by submitting any copyrighted material via pull request, email, or other means you agree to license the material under the project's open source license and warrant that you have the legal authority to do so.

This code is open source software licensed under the Apache 2.0 license.