Watcher plugin fixes

* com.noccy.watcher: Initial inotify support
* ScriptRunner now accepts an array of local vars for expansion
  when evaluating scripts

plugins/com.noccy.watcher/FileWatcher.php

@@ -17,10 +17,12 @@ class FileWatcher {
 
     public function __construct()
     {
-        if (extension_loaded('inotify')) {
-            $this->monitor = new MtimeMonitor();
-            //$this->monitor = new InotifyMonitor();
+        if (extension_loaded('inotify') && !getenv("SPARK_NO_INOTIFY")) {
+            //$this->monitor = new MtimeMonitor();
+            printf("Enabling inotify support, watching directories\n");
+            $this->monitor = new InotifyMonitor();
         } else {
+            printf("No inotify support, watching file mtimes\n");
             $this->monitor = new MtimeMonitor();
         }
         $this->scriptRunner = get_environment()->getScriptRunner();
@@ -38,7 +40,11 @@ class FileWatcher {
     private function triggerRule(Rule $rule) 
     {
         $actions = $rule->getActions();
-        $this->scriptRunner->evaluate($actions);
+        $locals = [
+            'WATCHER_RULE' => $rule->getName(),
+            'WATCHER_FILES' => join(" ",$rule->getWatchedFiles()),
+        ];
+        $this->scriptRunner->evaluate($actions, $locals);
     }
 
     public function loop()

plugins/com.noccy.watcher/Monitor/InotifyMonitor.php

@@ -0,0 +1,97 @@
+<?php
+
+namespace SparkPlug\Com\Noccy\Watcher\Monitor;
+
+use SparkPlug\Com\Noccy\Watcher\Rule;
+
+class InotifyMonitor implements MonitorInterface
+{
+    private array $rules = [];
+
+    private array $watched = [];
+
+    private array $modified = [];
+
+    private $fd;
+
+    public function __construct()
+    {
+        $this->fd = \inotify_init();   
+    }
+
+    public function __destruct()
+    {
+        if (is_resource($this->fd)) fclose($this->fd);
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public function add(Rule $rule)
+    {
+        $this->rules[] = $rule;
+
+        $paths = $rule->getWatchedFiles();
+        $check = [];
+        foreach ($paths as $path) {
+            if (str_contains($path, '*')) {
+                $check = array_merge($check, glob($path));
+            } else {
+                $check[] = $path;
+            }
+        }
+        $dirs = [];
+        foreach ($check as $path) {
+            $dir = is_dir($path) ? $path : dirname($path);
+            if (!array_key_exists($dir, $dirs)) {
+                $dirs[$dir] = $rule;
+                \inotify_add_watch($this->fd, $dir, \IN_ATTRIB);
+            }
+        }
+        $this->watched = array_merge($this->watched, $dirs);
+
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public function getModified(): array
+    {
+        $mod = $this->modified;
+        $this->modified = [];
+        return $mod;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public function getWatched(): array
+    {
+        return [];        
+    }
+
+    public function loop()
+    {
+        $read = [ $this->fd ];
+        $write = null;
+        $except = null;
+        $changed = [];
+        while (stream_select($read,$write,$except,0)) {
+            $events = \inotify_read($this->fd);
+            foreach ($events as $event) {
+                $changed[] = $event['name'];
+            }
+        }
+
+        foreach ($changed as $file) {
+            foreach ($this->watched as $dir=>$rule) {
+                if (file_exists($dir."/".$file)) {
+                    if (!in_array($rule, $this->modified)) {
+                        printf("~ modified: %s (%s)\n", $dir."/".$file, $rule->getName());
+                        $this->modified[] = $rule;
+                    }
+                }
+            }
+        }
+    }
+}

plugins/com.noccy.watcher/Monitor/MtimeMonitor.php

@@ -60,12 +60,13 @@ class MtimeMonitor implements MonitorInterface
         }
 
         foreach ($check as $path) {
+            if (!file_exists($path)) continue;
             if (empty($this->watched[$path])) {
                 $this->watched[$path] = filemtime($path);
             } else {
                 $mtime = filemtime($path);
                 if ($mtime > $this->watched[$path]) {
-                    printf("* modified: %s (%s)\n", $path, $rule->getName());
+                    printf("~ modified: %s (%s)\n", $path, $rule->getName());
                     $this->watched[$path] = $mtime;
                     if (!in_array($rule, $this->modified)) {
                         $this->modified[] = $rule;

plugins/com.noccy.watcher/README.md

@@ -34,4 +34,21 @@ issues.
 }
 ```
 
-The `initial-trigger` key controls whether the rule is triggered on startup.
+- `name` contains an optional name of the rule.
+- `initial-trigger` controls whether the rule is triggered on startup. If false
+  or not specified, the actions will be triggered when the file is modified
+  after startup.
+- `watch` is an array of files or wildcards to watch.
+- `actions` are script actions to invoke.
+
+The executed action will have access to the `WATCHER_RULE` and `WATCHER_FILES`
+variables for expansion.
+
+## Known issues
+
+- The *inotify* monitor will trigger whenever a file is changed in a watched
+  directory, even if an explicit file is set. For example, changing the file
+  `./templates/index.html` will trigger the rule for `./templates/style.scss`.
+  If you can't live with that, export `SPARK_NO_INOTIFY=1` before invoking!
+- The *mtime* monitor will poll the mtime of each watched file every check.
+  This works great if you are explicit in what you are watching.

src/Environment/ScriptRunner.php

@@ -26,16 +26,16 @@ class ScriptRunner
         $this->evaluate($script);
     }
 
-    public function evaluate(string|array $script)
+    public function evaluate(string|array $script, array $locals=[])
     {
         if (is_array($script)) {
             foreach ($script as $step) {
-                $this->evaluate($step);
+                $this->evaluate($step, $locals);
             }
             return;
         }
 
-        $script = $this->expandString($script);
+        $script = $this->expandString($script, $locals);
 
         // Determine what to do
         if (str_starts_with($script, '@')) {
@@ -81,10 +81,12 @@ class ScriptRunner
         }
     }
 
-    public function expandString(string $input)
+    public function expandString(string $input, array $locals=[])
     {
-        return preg_replace_callback('/(\$\{(.+?)\})/', function ($match) {
-
+        return preg_replace_callback('/(\$\{(.+?)\})/', function ($match) use ($locals) {
+            if (array_key_exists($match[2], $locals)) {
+                return $locals[$match[2]];
+            }
             return ($_ENV[$match[2]]??getenv($match[2]))??null;
         }, $input);
     }