README.md

@@ -11,7 +11,7 @@ another system.
 
 ## git-monitor
 
-The git-monitor is a system service, that monitors a target directory on the
+The git-monitor is a system service that monitors a target directory on the
 PiDP-10. It contains a file with a list of git repositories to monitor, one at a
 time. The service will check if any of the repositories changed, and pull them.
 After a successful pull a script will be called, if it exists, that allows the
@@ -36,3 +36,49 @@ service to be enabled on system boot, enable the service:
 ```bash
 sudo systemctl enable git-monitor.service
 ```
+
+### Configuration
+
+The service is usable immediately after installation. The service is configured
+through a series of environment variables, that can be set to change the default
+behaviour. There are five different environment variables to configure the
+service with:
+
+<table>
+  <tr>
+    <th>Environment Variable</th>
+    <th>Description</th>
+    <th>Default Value</th>
+  </tr>
+  <tr>
+    <td>GITMONITOR_URLS</td>
+    <td>A file that contains the list of observed repositories in a directory by name and URL.</td>
+    <td>/opt/src/repository.list</td>
+  </tr>
+  <tr>
+    <td>GITMONITOR_LOCAL_PATH</td>
+    <td>The path in which the clone repositories will be stored.</td>
+    <td>/opt/src</td>
+  </tr>
+  <tr>
+    <td>GITMONITOR_BRANCH_NAME</td>
+    <td>The name of the branch to observe.</td>
+    <td>develop</td>
+  </tr>
+  <tr>
+    <td>GITMONITOR_POLL_INTERVALL</td>
+    <td>The number of seconds to wait until the next poll.</td>
+    <td>30</td>
+  </tr>
+  <tr>
+    <td>GITMONITOR_LOCK_FILE</td>
+    <td>The lock file that is used to monitor the service. </td>
+    <td>/run/lock/git-monitor.lock</td>
+  </tr>
+</table>
+
+You can override these settings by creating an override file for the service
+unit. Create a new file
+`/etc/serviced/service/git-monitor.service.d/override.conf` by typing
+`sudo systemctl edit git-monitor.service`. You can then uncomment the
+`Environment` statements, and change the value of the variables accordingly.

services/git-monitor

@@ -1,12 +1,12 @@
 #!/bin/bash
 
-# Configuration (Customize these!)
+# Configuration
-REPO_URLS="/opt/src/repository.list"
+[[ "x${GITMONITOR_URLS}" == "x" ]] && GITMONITOR_URLS="/opt/src/repository.list"
-REPO_LOCAL_PATH="/opt/src"
+[[ "x${GITMONITOR_LOCAL_PATH}" == "x" ]] && GITMONITOR_LOCAL_PATH="/opt/src"
-BRANCH_NAME="develop"
+[[ "x${GITMONITOR_BRANCH_NAME}" == "x" ]] && GITMONITOR_BRANCH_NAME="develop"
-POLL_INTERVAL=60  # Seconds between checks
+[[ "x${GITMONITOR_POLL_INTERVAL}" == "x" ]] && GITMONITOR_POLL_INTERVAL=60  # Seconds between checks
-#LOG_FILE="/var/log/git-monitor.log" # Log file for recording actions
+[[ "x${GITMONITOR_LOCK_FILE}" == "x" ]] && GITMONITOR_LOCK_FILE="/run/lock/git-monitor.lock" # File to prevent multiple instances
-LOCK_FILE="/run/lock/git-monitor.lock" # File to prevent multiple instances
+
 IFS="|"
 
 # Functions
@@ -19,14 +19,14 @@ log_message() {
 }
 
 check_lock() {
-  if [ -f "$LOCK_FILE" ]; then
+  if [ -f "$GITMONITOR_LOCK_FILE" ]; then
     log_message "WARN" "Another instance is already running. Exiting."
     exit 1
   fi
 }
 
 create_lock() {
-  touch "$LOCK_FILE"
+  touch "$GITMONITOR_LOCK_FILE"
 }
 
 run_after() {
@@ -36,17 +36,17 @@ run_after() {
 
 initialize_repos() {
   while read -r repo_name repo_url; do
-    if [ ! -d "$REPO_LOCAL_PATH/$repo_name" ]; then
+    if [ ! -d "$GITMONITOR_LOCAL_PATH/$repo_name" ]; then
-      log_message "INFO" "Repository directory $REPO_LOCAL_PATH/$repo_name does not exist. Cloning..."
+      log_message "INFO" "Repository directory $GITMONITO_LOCAL_PATH/$repo_name does not exist. Cloning..."
-      mkdir -p "$REPO_LOCAL_PATH/$repo_name"
+      mkdir -p "$GITMONITOR_LOCAL_PATH/$repo_name"
-      git clone --depth 1 "$repo_url" "$REPO_LOCAL_PATH/$repo_name"
+      git clone --depth 1 "$repo_url" "$GITMONITOR_LOCAL_PATH/$repo_name"
       if [ $? -ne 0 ]; then
         log_message "ERROR" "Failed to clone repository. Exiting."
         exit 1
       fi
       log_message "INFO" "Repository cloned successfully."
     fi
-  done <$REPO_URLS
+  done <$GITMONITOR_URLS
 }
 
 check_for_updates() {
@@ -55,30 +55,32 @@ check_for_updates() {
   local current_commit_hash
 
   # Get the last known commit hash (from a file)
-  cd "$REPO_LOCAL_PATH/$repo_name"
+  cd "$GITMONITOR
-  if [ -f "$REPO_LOCAL_PATH/$repo_name/.git-monitor-last-commit" ]; then
+_LOCAL_PATH/$repo_name"
-    last_commit_hash=$(cat "$REPO_LOCAL_PATH/$repo_name/.git-monitor-last-commit")
+  if [ -f "$GITMONITOR_LOCAL_PATH/$repo_name/.git-monitor-last-commit" ]; then
+    last_commit_hash=$(cat "$GITMONITOR_LOCAL_PATH/$repo_name/.git-monitor-last-commit")
   else
     last_commit_hash="" # Initialize if file doesn't exist
   fi
 
   # Fetch the latest commit hash from the remote repository
-  git -C "$REPO_LOCAL_PATH/$repo_name" fetch origin $BRANCH_NAME
+  git -C "$GITMONITOR_LOCAL_PATH/$repo_name" fetch origin $GITMONITOR_BRANCH_NAME
-  current_commit_hash=$(git -C "$REPO_LOCAL_PATH/$repo_name" rev-parse origin $BRANCH_NAME)
+  current_commit_hash=$(git -C "$GITMONITOR_LOCAL_PATH/$repo_name" rev-parse origin $GITMONITOR_BRANCH_NAME)
 
   if [ -z "$last_commit_hash" ] || [ "$current_commit_hash" != "$last_commit_hash" ]; then
     log_message "INFO" "New commits detected. Pulling..."
-    git -C "$REPO_LOCAL_PATH/$repo_name" pull origin $BRANCH_NAME
+    git -C "$GITMONITOR
+  _LOCAL_PATH/$repo_name" pull origin $GITMONITOR_BRANCH_NAME
     if [ $? -eq 0 ]; then
       log_message "INFO" "Pull successful."
 
       # run local scripts
-      if [ -f "$REPO_LOCAL_PATH/$repo_name/.git-monitor_after.sh" ]; then
+      if [ -f "$GITMONITOR_LOCAL_PATH/$repo_name/.git-monitor_after.sh" ]; then
-        run_after "$REPO_LOCAL_PATH/$repo_name/.git-monitor_after.sh"
+        run_after "$GITMONITOR_LOCAL_PATH/$repo_name/.git-monitor_after.sh"
       fi
     
       # Update the last commit hash file
-      echo "$current_commit_hash" > "$REPO_LOCAL_PATH/$repo_name/.git-monitor-last-commit"
+      echo "$current_commit_hash" > "$GITMONITOR_LOCAL_PATH/$repo_name/.git-monitor-last-commit"
     else
       log_message "ERROR" "Pull failed."
     fi
@@ -87,7 +89,7 @@ check_for_updates() {
 
 # Main Execution
 
-trap 'rm -f $LOCK_FILE' EXIT
+trap 'rm -f $GITMONITOR_LOCK_FILE' EXIT
 
 check_lock
 create_lock
@@ -99,7 +101,7 @@ initialize_repos
 while true; do
   while read -r repo_name repo_url; do
     check_for_updates $repo_name
-  done < $REPO_URLS
+  done < $GITMONITOR_URLS
-  sleep "$POLL_INTERVAL"
+  sleep "$GITMONITOR_POLL_INTERVAL"
 done
 

units/git-monitor.service

@@ -7,6 +7,11 @@ ExecStart=/usr/local/bin/git-monitor
 Restart=on-failure
 User=monitor
 WorkingDirectory=/opt/src
+Environment="GITMONITOR_URLS=/opt/src/repository.list"
+Environment="GITMONITOR_LOCAL_PATH=/opt/src"
+Environment="GITMONITOR_BRANCH_NAME=develop"
+Environment="GITMONITOR_POLL_INTERVALL=30"
+Environment="GITMONITOR_LOCK_FILE=/run/lock/git-monitor.lock"
 
 [Install]
 WantedBy=multi-user.target