Add caching to localfilesystem context

red/api/admin/context.js

@@ -29,7 +29,6 @@ module.exports = {
         var scope = req.params.scope;
         var id = req.params.id;
         var key = req.params[0];
-        var result = {};
         var ctx;
         if (scope === 'global') {
             ctx = redNodes.getContext('global');
@@ -43,19 +42,28 @@ module.exports = {
         }
         if (ctx) {
             if (key) {
-                result = util.encodeObject({msg:ctx.get(key)});
+                ctx.get(key,function(err, v) {
+                    console.log(key,v);
+                    res.json(util.encodeObject({msg:v}));
+                });
+                return;
             } else {
-                var keys = ctx.keys();
-
-                var i = 0;
-                var l = keys.length;
-                while(i < l) {
-                    var k = keys[i];
-                    result[k] = util.encodeObject({msg:ctx.get(k)});
-                    i++;
-                }
-            }
-        }
+                ctx.keys(function(err, keys) {
+                    var result = {};
+                    var c = keys.length;
+                    keys.forEach(function(key) {
+                        ctx.get(key,function(err, v) {
+                            result[key] = util.encodeObject({msg:v});
+                            c--;
+                            if (c === 0) {
                                 res.json(result);
                             }
+                        });
+                    });
+                });
+            }
+        } else {
+            res.json({});
+        }
+    }
 }

red/runtime/nodes/context/localfilesystem.js

@@ -14,10 +14,39 @@
  * limitations under the License.
  **/
 
+/**
+ * Local file-system based context storage
+ *
+ * Configuration options:
+ * {
+ *    base: "contexts",        // the base directory to use
+ *                             // default: "contexts"
+ *    dir: "/path/to/storage", // the directory to create the base directory in
+ *                             // default: settings.userDir
+ *    cache: true              // whether to cache contents in memory
+ *                             // default: true
+ *  }
+ *
+ *
+ *  $HOME/.node-red/contexts
+ *  ├── global
+ *  │     └── global_context.json
+ *  ├── <id of Flow 1>
+ *  │     ├── flow_context.json
+ *  │     ├── <id of Node a>.json
+ *  │     └── <id of Node b>.json
+ *  └── <id of Flow 2>
+ *         ├── flow_context.json
+ *         ├── <id of Node x>.json
+ *         └── <id of Node y>.json
+ */
+
 var fs = require('fs-extra');
 var path = require("path");
 var util = require("../../util");
 
+var MemoryStore = require("./memory");
+
 function getStoragePath(storageBaseDir, scope) {
     if(scope.indexOf(":") === -1){
         if(scope === "global"){
@@ -76,17 +105,58 @@ function loadFile(storagePath){
 function LocalFileSystem(config){
     this.config = config;
     this.storageBaseDir = getBasePath(this.config);
+    if (config.hasOwnProperty('cache')?config.cache:true) {
+        this.cache = MemoryStore({});
+    }
 }
 
 LocalFileSystem.prototype.open = function(){
+    var self = this;
+    if (this.cache) {
+        var scopes = [];
+        var promises = [];
+        var subdirs = [];
+        var subdirPromises = [];
+        return fs.readdir(self.storageBaseDir).then(function(dirs){
+            dirs.forEach(function(fn) {
+                var p = getStoragePath(self.storageBaseDir ,fn)+".json";
+                scopes.push(fn);
+                promises.push(loadFile(p));
+                subdirs.push(path.join(self.storageBaseDir,fn));
+                subdirPromises.push(fs.readdir(path.join(self.storageBaseDir,fn)));
+            })
+            return Promise.all(subdirPromises);
+        }).then(function(dirs) {
+            dirs.forEach(function(files,i) {
+                files.forEach(function(fn) {
+                    if (fn !== 'flow.json' && fn !== 'global.json') {
+                        scopes.push(fn.substring(0,fn.length-5)+":"+scopes[i]);
+                        promises.push(loadFile(path.join(subdirs[i],fn)))
+                    }
+                });
+            })
+            return Promise.all(promises);
+        }).then(function(res) {
+            scopes.forEach(function(scope,i) {
+                var data = res[i]?JSON.parse(res[i]):{};
+                Object.keys(data).forEach(function(key) {
+                    self.cache.set(scope,key,data[key]);
+                })
+            });
+        })
+    } else {
         return Promise.resolve();
     }
+}
 
 LocalFileSystem.prototype.close = function(){
     return Promise.resolve();
 }
 
 LocalFileSystem.prototype.get = function(scope, key, callback) {
+    if (this.cache) {
+        return this.cache.get(scope,key,callback);
+    }
     if(typeof callback !== "function"){
         throw new Error("Callback must be a function");
     }
@@ -102,7 +172,7 @@ LocalFileSystem.prototype.get = function(scope, key, callback) {
     });
 };
 
-LocalFileSystem.prototype.set =function(scope, key, value, callback) {
+LocalFileSystem.prototype._set = function(scope, key, value, callback) {
     var storagePath = getStoragePath(this.storageBaseDir ,scope);
     loadFile(storagePath + ".json").then(function(data){
         var obj = data ? JSON.parse(data) : {}
@@ -117,9 +187,23 @@ LocalFileSystem.prototype.set =function(scope, key, value, callback) {
             callback(err);
         }
     });
+}
+
+LocalFileSystem.prototype.set = function(scope, key, value, callback) {
+    if (this.cache) {
+        this.cache.set(scope,key,value,callback);
+        this._set(scope,key,value, function(err) {
+            // TODO: log any errors
+        });
+    } else {
+        this._set(scope,key,value,callback);
+    }
 };
 
 LocalFileSystem.prototype.keys = function(scope, callback){
+    if (this.cache) {
+        return this.cache.keys(scope,callback);
+    }
     if(typeof callback !== "function"){
         throw new Error("Callback must be a function");
     }
@@ -136,12 +220,28 @@ LocalFileSystem.prototype.keys = function(scope, callback){
 };
 
 LocalFileSystem.prototype.delete = function(scope){
-    var storagePath = getStoragePath(this.storageBaseDir ,scope);
+    var cachePromise;
+    if (this.cache) {
+        cachePromise = this.cache.delete(scope);
+    } else {
+        cachePromise = Promise.resolve();
+    }
+    var that = this;
+    return cachePromise.then(function() {
+        var storagePath = getStoragePath(that.storageBaseDir,scope);
         return fs.remove(storagePath + ".json");
+    });
 }
 
 LocalFileSystem.prototype.clean = function(activeNodes){
     var self = this;
+    var cachePromise;
+    if (this.cache) {
+        cachePromise = this.cache.clean(activeNodes);
+    } else {
+        cachePromise = Promise.resolve();
+    }
+    return cachePromise.then(function() {
         return fs.readdir(self.storageBaseDir).then(function(dirs){
             return Promise.all(dirs.reduce(function(result, item){
                 if(item !== "global" && activeNodes.indexOf(item) === -1){
@@ -156,9 +256,9 @@ LocalFileSystem.prototype.clean = function(activeNodes){
                 return Promise.reject(err);
             }
         });
+    });
 }
 
 module.exports = function(config){
     return new LocalFileSystem(config);
 };
-

test/red/runtime/nodes/context/localfilesystem_spec.js

@@ -29,7 +29,7 @@ describe('localfilesystem',function() {
     });
 
     beforeEach(function() {
-        context = LocalFileSystem({dir: resourcesDir});
+        context = LocalFileSystem({dir: resourcesDir, cache: false});
         return context.open();
     });
 
@@ -308,7 +308,7 @@ describe('localfilesystem',function() {
                                                 done();
                                             });
                                         });
-                                    });
+                                    }).catch(done);
                                 });
                             });
                         });