Moved WatchManager.js from WatchKeeper (#283)

* Moved WatchManager.js from WatchKeeper

* add WatchManager to module exports

* npm audit fix

* Revert "npm audit fix"

This reverts commit c445e25.

* npm audit fix take 2

* Apply suggestions from code review

Co-authored-by: Adam King <rak@us.ibm.com>

* update index.js copywrite note

* replace lets/vars with const

* changed missed let

Co-authored-by: Adam King <rak@us.ibm.com>

index.js

@@ -1,5 +1,5 @@
 /**
-* Copyright 2019 IBM Corp. All Rights Reserved.
+* Copyright 2019, 2022 IBM Corp. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
@@ -24,10 +24,13 @@ const Watchman = require('./lib/Watchman');
 
 const EventHandler = require('./lib/EventHandler');
 
+const WatchManager = require('./lib/WatchManager');
+
 module.exports = {
   KubeClass,
   KubeApiConfig,
   KubeResourceMeta,
   Watchman,
-  EventHandler
+  EventHandler,
+  WatchManager
 };

lib/WatchManager.js

@@ -0,0 +1,94 @@
+/**
+ * Copyright 2019, 2022 IBM Corp. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+const Watchman = require('./Watchman');
+const log = require('./bunyan-api').createLogger('WatchManager');
+const objectPath = require('object-path');
+const hash = require('object-hash');
+
+const _watchObjects = {};
+
+module.exports = function WatchManager() {
+  // private
+  const _saveWatch = function (wm, querySelector, startWatch = true) {
+    const selfLink = wm.selfLink;
+    _removeWatch(selfLink);
+    _watchObjects[selfLink] = { selfLink: wm.selfLink, watchman: wm, querySelectorHash: hash(querySelector) };
+    if (startWatch) {
+      wm.watch();
+    }
+    log.info(`Watch added: ${selfLink} ${JSON.stringify(querySelector)}`);
+    return _watchObjects[selfLink];
+  };
+
+  const _ensureWatch = function (options, objectHandler, globalWatch = false, startWatch = true) {
+    const querySelector = objectPath.get(options, 'requestOptions.qs', {});
+    const selfLink = options?.requestOptions?.uri;
+    const w = _getWatch(selfLink);
+    if (w && (!globalWatch || (globalWatch && w.querySelectorHash == hash(querySelector)))) {
+      return w;
+    }
+    const wm = new Watchman(options, objectHandler);
+    return _saveWatch(wm, querySelector, startWatch);
+  };
+
+  const _startWatch = function (selfLink) {
+    return _reWatch(selfLink);
+  };
+
+  const _removeWatch = function (selfLink) {
+    const w = objectPath.get(_getWatch(selfLink), 'watchman');
+    if (w) {
+      w.end();
+      delete _watchObjects[selfLink];
+      log.info(`Watch removed: ${selfLink}`);
+    }
+    return _watchObjects[selfLink];
+  };
+
+  const _getWatch = function (selfLink) {
+    return _watchObjects[selfLink];
+  };
+
+  const _reWatch = function (selfLink) {
+    const w = objectPath.get(_getWatch(selfLink), 'watchman');
+    if (w) {
+      w.watch();
+    }
+    return w;
+  };
+
+  // public
+  return {
+    saveWatch: _saveWatch,
+    ensureWatch: _ensureWatch,
+    startWatch: _startWatch,
+    removeWatch: _removeWatch,
+    removeAllWatches: function () {
+      const watches = Object.keys(_watchObjects);
+      watches.forEach(w => _removeWatch(w));
+    },
+    getWatch: _getWatch,
+    getAllWatches: function () {
+      return _watchObjects;
+    },
+    reWatch: _reWatch,
+    reWatchAll: function () {
+      const watches = Object.keys(_watchObjects);
+      watches.forEach(w => _reWatch(w));
+    }
+  };
+};