add git:unlock functionality

docs/deployment/methods/git.md

@@ -12,6 +12,7 @@ git:initialize <app>                              # Initialize a git repository
 git:public-key                                    # Outputs the dokku public deploy key
 git:report [<app>] [<flag>]                       # Displays a git report for one or more apps
 git:set <app> <key> (<value>)                     # Set or clear a git property for an app
+git:unlock <app>                                  # Removes previous git clone folder for new deployment
 ```
 
 Git-based deployment has been the traditional method of deploying applications in Dokku. As of v0.12.0, Dokku introduces a few ways to customize the experience of deploying via `git push`. A Git-based deployment currently supports building applications via:

plugins/git/help-functions

@@ -36,5 +36,6 @@ fn-help-content() {
     git:public-key, Outputs the dokku public deploy key
     git:report [<app>] [<flag>], Displays a git report for one or more apps
     git:set <app> <property> (<value>), Set or clear a git property for an app
+    git:unlock <app>, Removes previous git clone folder for new deployment 
 help_content
 }

plugins/git/internal-functions

@@ -193,6 +193,20 @@ cmd-git-sync() {
 
   verify_app_name "$APP"
 
+  if [[ -d "$DOKKU_LIB_ROOT/data/git/$APP" ]]; then 
+    if [[ has_tty ]]; then 
+    cmd-git-unlock "$APP"
+      if [[ -d "$DOKKU_LIB_ROOT/data/git/$APP" ]]; then
+      dokku_log_fail "Failed to delete existing clone folder"
+      exit 15
+      fi
+    else 
+    dokku_log_fail "Missing tty, try running ssh -t which will allocate new tty for you"  
+    fi
+  else 
+    dokku_log_info1 "No need to unlock app, carrying on with build"
+  fi
+
   if [[ -z "$GIT_REMOTE" ]]; then
     dokku_log_fail "Missing GIT_REMOTE parameter"
     return
@@ -215,6 +229,26 @@ cmd-git-sync() {
   fi
 }
 
+cmd-git-unlock() {
+  declare desc="removes the clone folder for an app"
+  local cmd="git:unlock"
+  [[ "$1" == "$cmd" ]] && shift 1
+  declare APP
+
+  APP="${ARGS[0]}"
+
+  local APP_CLONE_ROOT="$DOKKU_LIB_ROOT/data/git/$APP"
+
+  if [[ -d "$APP_CLONE_ROOT" ]]; then
+    dokku_log_info1 "About to delete $APP_CLONE_ROOT"
+    rm -rf "$APP_CLONE_ROOT" 
+  else 
+    dokku_log_info1 "No clone folder exists app already unlocked"
+  fi
+
+  dokku_log_info1 "Successfully unlocked $APP"
+}
+
 cmd-git-public-key() {
   declare desc="outputs the dokku public deploy key"
   local cmd="git:public-key"
@@ -331,10 +365,6 @@ fn-git-clone() {
     dokku_log_fail "The clone subcommand can only be executed for new applications"
   fi
 
-  if [[ -d "$APP_CLONE_ROOT" ]]; then
-    dokku_log_fail "Clone in progress"
-  fi
-
   if [[ -z "$GIT_REF" ]]; then
     GIT_REF="$(fn-git-deploy-branch "$APP")"
   fi

plugins/git/subcommands/unlock

@@ -0,0 +1,6 @@
+#!/usr/bin/env bash
+source "$PLUGIN_AVAILABLE_PATH/git/internal-functions"
+set -eo pipefail
+[[ $DOKKU_TRACE ]] && set -x
+
+cmd-git-unlock "$@"