sbt-git-flow-version is an sbt plugin for automation git flow based versioning.

If you using git flow for your projects development you possible know that it is quite annoying to switch between different branches and with different versions. This plugin allows you to define different versioning rules for different branches and change versions automatically without changing your code.

Java 8 and sbt 1.x, or, if you brave enought sbt 2.0.0-RC2. This plugin depends on sbt-git.

Note: if you are still using sbt 0.13.5+, you can use sbt-git-flow-version 0.3 or eariler.

addSbtPlugin("me.limansky" % "sbt-git-flow-version" % "0.6")

The heart of the plugin configuration is a versionPolicy setting which defines version rules as a tuple of BranchMatcher and VersionCalculator. Let's start with branch matchers. Branch matcher is a function taking branch name and returning Option[Matching]. Matching is a class containing matched branch name and optional extraction. There are number of built-in matchers:

• exact(name: String) - branch name is equals to name
• prefix(prefix: String) - branch name starts with prefix. The part after prefix is extraction.
• prefixes(prefixes: String*) - same as prefix but supports a number of prefixes.
• regex(r: String) - branch name matches regular expression r. If the expression contains groups, the first group will be returned as extraction.
• any - matches any branch (might be used to define default behaviour).

There are also several built in implementations for VersionCalculator:

• currentTag - take a version from a current tag. If there are several current tags it will take the one with a maximal version.
• nextMajor, nextMinor, nextBuild, nextN - increment major, minor, build or n-th number of a last version. The version is snapshot by default.
• nextGlobalMajor, nextGlobalMinor, nextGlobalBuild, nextGlobalN - same as nextX, but trying to find maximal available version not only merged to current branch, but even for not merged and remote branches.
• matching - take a version from matching returned by BranchMatcher. The version is snapshot by default.
• lastVersion - previous version. Version value is taken from last tag or initialVersion setting. The version is not snapshot by default.
• lastVersionWithMatching - takes last version and append matching returned by BranchMatcher. By default new version is snapshot.
• lastVersionWithSuffix - takes fixed suffix to append to the last version. By default new version is snapshot.
• fixed - takes flag if the version is snapshot and numbers. Just fixed version.
• unknownVersion - fails with unknown version message.

Note: calculating global version might take a long time if you have a lot of branches, so, to speed up the process it doesn't take in account all branches, but only the ones for those VersionCalculator has a global version flag. By default it matching policy. This means, that by default when calculating develop version it use tags and and release/xxx branches only.

So, the default policy is:

Seq(
  exact("master") -> currentTag(),
  exact("develop") -> nextGlobalMinor(),
  prefix("release/") -> matching(),
  prefixes("feature/", "bugfix/", "hotfix/") -> lastVersionWithMatching(),
  any -> unknownVersion
)

Which can be described as following rules:

• If branch name is "master" then the branch name is a current commit tag
• If branch name is "develop" then the branch name is a next global minor version. E.g. if last version was 1.4.2, the current version is 1.5.0-SNAPSHOT.
• If the branch name starts with "release/" then the version is taken from the branch name. E.g. for the branch "release/2.12.85" the version is "2.12.85-SNAPSHOT".
• For the branches started with "feature/", "bugfix/", and "hotfix/" the version is a combination of the last version and matching. E.g. for the branch "feature/123-new-ui" and the prevous version "1.0.1" the current version is "1.0.1-123-new-ui-SNAPSHOT".
• Finally, if the branch name doesn't follow any of these rules, the build fails, because version is unknown.

By default sbt-git-flow-version expects version in the tags as is (e.g. "1.0.1"). You can change this behaviour if you are using some prefixes or/and suffixes in your tag names. To do that use tagMatcher setting with TagMatcher class. Following tag matchers are available:

• raw - default tag matcher, takes the version as is.
• prefix(p: String) - tag should be started with prefix p (e.g. prefix("Version_") matches version 3.2.1 from tag "Version_3.2.1").
• suffix(s: String) - tag should be ended with suffix s.
• prefixAndSuffix(p: String, s:String) - tag should start with prefix p and end with suffix s.