From a40025d8427cf225d47d932d80aaab9a8025f041 Mon Sep 17 00:00:00 2001
From: Evilham <cvs@evilham.com>
Date: Thu, 18 Jun 2020 00:47:16 +0200
Subject: [PATCH] [__git] Implement onchange triggers and messaging.

Closes #820.
---
 cdist/conf/type/__git/gencode-remote           | 18 +++++++++++++++++-
 cdist/conf/type/__git/man.rst                  | 15 +++++++++++++++
 .../conf/type/__git/parameter/default/onchange |  0
 cdist/conf/type/__git/parameter/optional       |  1 +
 4 files changed, 33 insertions(+), 1 deletion(-)
 create mode 100644 cdist/conf/type/__git/parameter/default/onchange

diff --git a/cdist/conf/type/__git/gencode-remote b/cdist/conf/type/__git/gencode-remote
index d52d44e1..7e0118fc 100755
--- a/cdist/conf/type/__git/gencode-remote
+++ b/cdist/conf/type/__git/gencode-remote
@@ -71,16 +71,24 @@ EOF
             fi
             # Actually clone the repository
             su -m "$git_user" -c "git clone --quiet '$recursive' '$shallow' --branch '$branch' '$source' '$destination'"
+            echo create >> "$__messages_out"
+            repo_changed="YES"
         elif [ "$branch_should" != "$branch_is" ]; then
             # User has changed tag / branch, let's update that
             echo su -m "$git_user" -c "git checkout '$branch_should'"
+            echo "change $branch_is -> $branch_should" >> "$__messages_out"
+            repo_changed="YES"
         elif [ "$needs_update" = "YES" ]; then
             # The remote has newer information than our repository.
             # Fetch was done in the explorer, here we can just pull
             echo su -m "$git_user" -c "git -C '$destination' pull"
+            echo update >> "$__messages_out"
+            repo_changed="YES"
         fi
         if [ -n "$needs_chown" ]; then
             echo chown -R "${owner}:${group}" "$destination"
+            echo "chown -R '${owner}:${group}'" >> "$__messages_out"
+            repo_changed="YES"
         fi
         if [ -f "$__object/parameter/mode-recursive" ]; then
             mode_recursive="-R"
@@ -91,7 +99,11 @@ EOF
     ;;
 
     absent)
-        # Handled in manifest
+        # Handled in manifest, except for the change triggers
+        if [ "$state_should" != "$state_is" ]; then
+            echo remove >> "$__messages_out"
+            repo_changed="YES"
+        fi
     ;;
 
     *)
@@ -99,3 +111,7 @@ EOF
         exit 1
     ;;
 esac
+
+if [ -n "$repo_changed" ]; then
+    cat "$__object/parameter/onchange"
+fi
diff --git a/cdist/conf/type/__git/man.rst b/cdist/conf/type/__git/man.rst
index dfcbc0f6..2db4d548 100644
--- a/cdist/conf/type/__git/man.rst
+++ b/cdist/conf/type/__git/man.rst
@@ -35,6 +35,9 @@ mode
    By default it only applies to the top-level directory.
    See the mode-recursive parameter as well.
 
+onchange
+   The code to run if the repository is first-cloned, changes or is removed.
+
 owner
    User to chown to.
 
@@ -50,6 +53,18 @@ recursive
 shallow
    Sets --depth=1 and --shallow-submodules for cloning repositories with big history.
 
+MESSAGES
+--------
+change <old_branch> -> <new_branch>
+    The directory tracks old_branch but should track new_branch, it will be changed
+chown -R <owner>:<group>
+    Changed ownership
+create
+    Freshly created the directory with the repository clone
+remove
+    The directory with the repository exists, but state is absent, it will be removed
+update
+    The repository tracks a branch that has been updated on the remote
 
 EXAMPLES
 --------
diff --git a/cdist/conf/type/__git/parameter/default/onchange b/cdist/conf/type/__git/parameter/default/onchange
new file mode 100644
index 00000000..e69de29b
diff --git a/cdist/conf/type/__git/parameter/optional b/cdist/conf/type/__git/parameter/optional
index 3c409162..13feb97e 100644
--- a/cdist/conf/type/__git/parameter/optional
+++ b/cdist/conf/type/__git/parameter/optional
@@ -1,5 +1,6 @@
 state
 branch
 group
+onchange
 owner
 mode