Add documentation for automerger plugin
Change-Id: I2944b75bcc43314c02419a5b9144349461b1654a
diff --git a/src/main/resources/Documentation/config.md b/src/main/resources/Documentation/config.md
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+@PLUGIN@ Configuration
+======================
+
+The configuration of the @PLUGIN@ plugin is done on the project level in
+the `@PLUGIN@.config` file of the project.
+
+```
+ [global]
+ automergeLabel = Code-Review
+ hostName = https://hostname.example.com
+ conflictMessage = Merge conflict found on ${branch}\n\
+" # Example of multiline conflict message"
+ manifestProject = platform/manifest
+ manifestFile = default.xml
+ alwaysBlankMerge = .*SKIP ME ALWAYS.*
+ blankMerge = .*RESTRICT AUTOMERGE.*
+ blankMerge = .*SKIP UNLESS MERGEALL SET.*
+
+ [@PLUGIN@ "branch1:branch2"]
+ setProjects = some/project
+ addProjects = some/other/project
+ ignoreProjects = some/ignored/project
+ mergeAll = True
+ ignoreSourceManifest = False
+```
+
+global.automergeLabel
+: Label to vote -1 on when there is a merge conflict.
+
+ When the automerger detects a merge conflict from one branch to another, it
+ will vote -1 on this label.
+
+global.hostName
+: Hostname to use in a custom conflict message.
+
+ The automerger will attempt to use the canonicalWebUrl to fill in the
+ hostname. However, if it is unable to do so for whatever reason, it can be
+ overriden using this field.
+
+global.conflictMessage
+: Message to comment with the automergeLabel vote if there is a merge conflict.
+
+ When the automerger detects a merge conflict from one branch to another, it
+ will vote -1 on the automergeLabel. The message on the vote can be custom
+ configured to include:
+
+ - branch
+ - revision
+ - hostname
+ - topic
+ - conflict
+
+ For example, you could configure the @PLUGIN@.config to include:
+
+ ```
+ conflictMessage = Conflict message ${conflict} found on branch ${branch}
+ ```
+
+global.manifestProject
+: Project to look for a [repo manifest][1] in.
+
+ The automerger will attempt to look for the manifest project in this project.
+
+global.manifestFile
+: File to look for a [repo manifest][1] in.
+
+ The automerger will attempt to look for a repo manifest in this file.
+
+[1]: https://gerrit.googlesource.com/git-repo/
+
+global.blankMerge
+: Pattern for skipping changes.
+
+ If the automerger matches this regex in the subject of the change, it will
+ merge with "-s ours" to all downstream branches, effectively skipping the
+ change.
+
+ If mergeAll is set to True for a branch, however, it will merge downstream
+ normally for that branch.
+
+global.alwaysBlankMerge
+: Pattern for always skipping changes.
+
+ If the automerger matches this regex in the subject of the change, it will
+ merge with "-s ours" to all downstream branches, effectively skipping the
+ change.
+
+ Even if mergeAll is set to True for a branch, it will still merge with
+ "-s ours".
+
+@PLUGIN@.branch1:branch2.setProjects
+: Projects to automerge for.
+
+ If setProjects is set, it overrides the default scope.
+
+@PLUGIN@.branch1:branch2.addProjects
+: Projects to add on top of the projects already in scope.
+
+ If setProjects is set, this will add projects on top of the setProjects.
+ If setProjects is not set, this will add projects on top of the default scope.
+
+@PLUGIN@.branch1:branch2.ignoreProjects
+: Projects to ignore on top of the projects already in scope
+
+ If setProjects is set, this will ignore projects on top of the setProjects.
+ If setProjects is not set, this will ignore projects on top of the default
+ scope.
+
+@PLUGIN@.branch1:branch2.mergeAll
+: If this is true, the blankMerge regex will be ignored.
+
+ When mergeAll is true, the blankMerge regex will be ignored but the
+ alwaysBlankMerge regex will still be honored.
+
+@PLUGIN@.branch1:branch2.ignoreSourceManifest
+: If this is true, the default scope will be modified.
+
+ The default scope normally includes the intersection of all projects in the
+ manifest of branch1 whose revisions are branch1, and all projects in the
+ manifest of branch2 whose revisions are branch2.
+
+ If ignoreSourceManifest is true, the scope will become all projects in the
+ manifest of branch2 whose revisions are branch2.
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