Add JSDoc to server/modules/apicache/*

Signed-off-by: Matthew Nickson <mnickson@sidingsmedia.com>

server/modules/apicache/apicache.js

@@ -13,27 +13,49 @@ let t = {
 
 let instances = [];
 
+/**
+ * Does a === b
+ * @param {any} a
+ * @returns {function(any): boolean}
+ */
 let matches = function (a) {
     return function (b) {
         return a === b;
     };
 };
 
+/**
+ * Does a!==b
+ * @param {any} a
+ * @returns {function(any): boolean}
+ */
 let doesntMatch = function (a) {
     return function (b) {
         return !matches(a)(b);
     };
 };
 
+/**
+ * Get log duration
+ * @param {number} d Time in ms
+ * @param {string} prefix Prefix for log
+ * @returns {string} Coloured log string
+ */
 let logDuration = function (d, prefix) {
     let str = d > 1000 ? (d / 1000).toFixed(2) + "sec" : d + "ms";
     return "\x1b[33m- " + (prefix ? prefix + " " : "") + str + "\x1b[0m";
 };
 
+/**
+ * Get safe headers
+ * @param {Object} res Express response object
+ * @returns {Object}
+ */
 function getSafeHeaders(res) {
     return res.getHeaders ? res.getHeaders() : res._headers;
 }
 
+/** Constructor for ApiCache instance */
 function ApiCache() {
     let memCache = new MemoryCache();
 
@@ -70,10 +92,10 @@ function ApiCache() {
 
     /**
      * Logs a message to the console if the `DEBUG` environment variable is set.
-     * @param {string} a - The first argument to log.
+     * @param {string} a The first argument to log.
-     * @param {string} b - The second argument to log.
+     * @param {string} b The second argument to log.
-     * @param {string} c - The third argument to log.
+     * @param {string} c The third argument to log.
-     * @param {string} d - The fourth argument to log, and so on... (optional)
+     * @param {string} d The fourth argument to log, and so on... (optional)
      *
      * Generated by Trelent
      */
@@ -90,8 +112,8 @@ function ApiCache() {
      * Returns true if the given request and response should be logged.
      * @param {Object} request The HTTP request object.
      * @param {Object} response The HTTP response object.
-     *
+     * @param {function(Object, Object):boolean} toggle
-     * Generated by Trelent
+     * @returns {boolean}
      */
     function shouldCacheResponse(request, response, toggle) {
         let opt = globalOptions;
@@ -116,10 +138,9 @@ function ApiCache() {
     }
 
     /**
-     * Adds a key to the index.
+     * Add key to index array
-     * @param {string} key The key to add.
+     * @param {string} key Key to add
-     *
+     * @param {Object} req Express request object
-     * Generated by Trelent
      */
     function addIndexEntries(key, req) {
         let groupName = req.apicacheGroup;
@@ -135,8 +156,11 @@ function ApiCache() {
 
     /**
      * Returns a new object containing only the whitelisted headers.
-     * @param {Object} headers The original object of header names and values.
+     * @param {Object} headers The original object of header names and
-     * @param {Array.<string>} globalOptions.headerWhitelist An array of strings representing the whitelisted header names to keep in the output object.
+     * values.
+     * @param {string[]} globalOptions.headerWhitelist An array of
+     * strings representing the whitelisted header names to keep in the
+     * output object.
      *
      * Generated by Trelent
      */
@@ -152,8 +176,10 @@ function ApiCache() {
     }
 
     /**
+     * Create a cache object
      * @param {Object} headers The response headers to filter.
-     * @returns {Object} A new object containing only the whitelisted response headers.
+     * @returns {Object} A new object containing only the whitelisted
+     * response headers.
      *
      * Generated by Trelent
      */
@@ -170,8 +196,9 @@ function ApiCache() {
     /**
      * Sets a cache value for the given key.
      * @param {string} key The cache key to set.
-     * @param {*} value The cache value to set.
+     * @param {any} value The cache value to set.
-     * @param {number} duration How long in milliseconds the cached response should be valid for (defaults to 1 hour).
+     * @param {number} duration How long in milliseconds the cached
+     * response should be valid for (defaults to 1 hour).
      *
      * Generated by Trelent
      */
@@ -199,7 +226,8 @@ function ApiCache() {
 
     /**
      * Appends content to the response.
-     * @param {string|Buffer} content The content to append.
+     * @param {Object} res Express response object
+     * @param {(string|Buffer)} content The content to append.
      *
      * Generated by Trelent
      */
@@ -229,11 +257,15 @@ function ApiCache() {
     }
 
     /**
-     * Monkeypatches the response object to add cache control headers and create a cache object.
+     * Monkeypatches the response object to add cache control headers
-     * @param {Object} req - The request object.
+     * and create a cache object.
-     * @param {Object} res - The response object.
+     * @param {Object} req Express request object
-     *
+     * @param {Object} res Express response object
-     * Generated by Trelent
+     * @param {function} next Function to call next
+     * @param {string} key Key to add response as
+     * @param {number} duration Time to cache response for
+     * @param {string} strDuration Duration in string form
+     * @param {function(Object, Object):boolean} toggle
      */
     function makeResponseCacheable(req, res, next, key, duration, strDuration, toggle) {
     // monkeypatch res.end to create cache object
@@ -302,11 +334,15 @@ function ApiCache() {
     }
 
     /**
-     * @param {Request} request
+     * Send a cached response to client
-     * @param {Response} response
+     * @param {Request} request Express request object
-     * @returns {boolean|undefined} true if the request should be cached, false otherwise. If undefined, defaults to true.
+     * @param {Response} response Express response object
-     *
+     * @param {object} cacheObject Cache object to send
-     * Generated by Trelent
+     * @param {function(Object, Object):boolean} toggle
+     * @param {function} next Function to call next
+     * @param {number} duration Not used
+     * @returns {boolean|undefined} true if the request should be
+     * cached, false otherwise. If undefined, defaults to true.
      */
     function sendCachedResponse(request, response, cacheObject, toggle, next, duration) {
         if (toggle && !toggle(request, response)) {
@@ -348,12 +384,19 @@ function ApiCache() {
         return response.end(data, cacheObject.encoding);
     }
 
+    /** Sync caching options */
     function syncOptions() {
         for (let i in middlewareOptions) {
             Object.assign(middlewareOptions[i].options, globalOptions, middlewareOptions[i].localOptions);
         }
     }
 
+    /**
+     * Clear key from cache
+     * @param {string} target Key to clear
+     * @param {boolean} isAutomatic Is the key being cleared automatically
+     * @returns {number}
+     */
     this.clear = function (target, isAutomatic) {
         let group = index.groups[target];
         let redis = globalOptions.redisClient;
@@ -430,10 +473,11 @@ function ApiCache() {
 
     /**
      * Converts a duration string to an integer number of milliseconds.
-     * @param {string} duration - The string to convert.
+     * @param {(string|number)} duration The string to convert.
-     * @returns {number} The converted value in milliseconds, or the defaultDuration if it can't be parsed.
+     * @param {number} defaultDuration The default duration to return if
-     *
+     * can't parse duration
-     * Generated by Trelent
+     * @returns {number} The converted value in milliseconds, or the
+     * defaultDuration if it can't be parsed.
      */
     function parseDuration(duration, defaultDuration) {
         if (typeof duration === "number") {
@@ -457,17 +501,24 @@ function ApiCache() {
         return defaultDuration;
     }
 
+    /**
+     * Parse duration
+     * @param {(number|string)} duration
+     * @returns {number} Duration parsed to a number
+     */
     this.getDuration = function (duration) {
         return parseDuration(duration, globalOptions.defaultDuration);
     };
 
     /**
-   * Return cache performance statistics (hit rate).  Suitable for putting into a route:
+   * Return cache performance statistics (hit rate).  Suitable for
+   * putting into a route:
    * <code>
    * app.get('/api/cache/performance', (req, res) => {
    *    res.json(apicache.getPerformance())
    * })
    * </code>
+   * @returns {any[]}
    */
     this.getPerformance = function () {
         return performanceArray.map(function (p) {
@@ -475,6 +526,11 @@ function ApiCache() {
         });
     };
 
+    /**
+     * Get index of a group
+     * @param {string} group 
+     * @returns {number}
+     */
     this.getIndex = function (group) {
         if (group) {
             return index.groups[group];
@@ -483,6 +539,14 @@ function ApiCache() {
         }
     };
 
+    /**
+     * Express middleware
+     * @param {(string|number)} strDuration Duration to cache responses
+     * for.
+     * @param {function(Object, Object):boolean} middlewareToggle 
+     * @param {Object} localOptions Options for APICache
+     * @returns 
+     */
     this.middleware = function cache(strDuration, middlewareToggle, localOptions) {
         let duration = instance.getDuration(strDuration);
         let opt = {};
@@ -513,35 +577,41 @@ function ApiCache() {
         }
 
         /**
-     * A function for tracking and reporting hit rate.  These statistics are returned by the getPerformance() call above.
+         * A function for tracking and reporting hit rate.  These
+         * statistics are returned by the getPerformance() call above.
          */
         function CachePerformance() {
             /**
-       * Tracks the hit rate for the last 100 requests.
+             * Tracks the hit rate for the last 100 requests. If there
-       * If there have been fewer than 100 requests, the hit rate just considers the requests that have happened.
+             * have been fewer than 100 requests, the hit rate just
+             * considers the requests that have happened.
              */
             this.hitsLast100 = new Uint8Array(100 / 4); // each hit is 2 bits
 
             /**
-       * Tracks the hit rate for the last 1000 requests.
+             * Tracks the hit rate for the last 1000 requests. If there
-       * If there have been fewer than 1000 requests, the hit rate just considers the requests that have happened.
+             * have been fewer than 1000 requests, the hit rate just
+             * considers the requests that have happened.
              */
             this.hitsLast1000 = new Uint8Array(1000 / 4); // each hit is 2 bits
 
             /**
-       * Tracks the hit rate for the last 10000 requests.
+             * Tracks the hit rate for the last 10000 requests. If there
-       * If there have been fewer than 10000 requests, the hit rate just considers the requests that have happened.
+             * have been fewer than 10000 requests, the hit rate just
+             * considers the requests that have happened.
              */
             this.hitsLast10000 = new Uint8Array(10000 / 4); // each hit is 2 bits
 
             /**
-       * Tracks the hit rate for the last 100000 requests.
+             * Tracks the hit rate for the last 100000 requests. If
-       * If there have been fewer than 100000 requests, the hit rate just considers the requests that have happened.
+             * there have been fewer than 100000 requests, the hit rate
+             * just considers the requests that have happened.
              */
             this.hitsLast100000 = new Uint8Array(100000 / 4); // each hit is 2 bits
 
             /**
-       * The number of calls that have passed through the middleware since the server started.
+             * The number of calls that have passed through the
+             * middleware since the server started.
              */
             this.callCount = 0;
 
@@ -551,17 +621,20 @@ function ApiCache() {
             this.hitCount = 0;
 
             /**
-       * The key from the last cache hit.  This is useful in identifying which route these statistics apply to.
+             * The key from the last cache hit.  This is useful in
+             * identifying which route these statistics apply to.
              */
             this.lastCacheHit = null;
 
             /**
-       * The key from the last cache miss.  This is useful in identifying which route these statistics apply to.
+             * The key from the last cache miss.  This is useful in
+             * identifying which route these statistics apply to.
              */
             this.lastCacheMiss = null;
 
             /**
              * Return performance statistics
+             * @returns {Object}
              */
             this.report = function () {
                 return {
@@ -579,9 +652,12 @@ function ApiCache() {
             };
 
             /**
-       * Computes a cache hit rate from an array of hits and misses.
+             * Computes a cache hit rate from an array of hits and
-       * @param {Uint8Array} array An array representing hits and misses.
+             * misses.
-       * @returns a number between 0 and 1, or null if the array has no hits or misses
+             * @param {Uint8Array} array An array representing hits and
+             * misses.
+             * @returns {number} a number between 0 and 1, or null if
+             * the array has no hits or misses
              */
             this.hitRate = function (array) {
                 let hits = 0;
@@ -608,15 +684,16 @@ function ApiCache() {
             };
 
             /**
-       * Record a hit or miss in the given array.  It will be recorded at a position determined
+             * Record a hit or miss in the given array.  It will be
-       * by the current value of the callCount variable.
+             * recorded at a position determined by the current value of
-       * @param {Uint8Array} array An array representing hits and misses.
+             * the callCount variable.
+             * @param {Uint8Array} array An array representing hits and
+             * misses.
              * @param {boolean} hit true for a hit, false for a miss
-       * Each element in the array is 8 bits, and encodes 4 hit/miss records.
+             * Each element in the array is 8 bits, and encodes 4
-       * Each hit or miss is encoded as to bits as follows:
+             * hit/miss records. Each hit or miss is encoded as to bits
-       * 00 means no hit or miss has been recorded in these bits
+             * as follows: 00 means no hit or miss has been recorded in
-       * 01 encodes a hit
+             * these bits 01 encodes a hit 10 encodes a miss
-       * 10 encodes a miss
              */
             this.recordHitInArray = function (array, hit) {
                 let arrayIndex = ~~(this.callCount / 4) % array.length;
@@ -627,8 +704,10 @@ function ApiCache() {
             };
 
             /**
-       * Records the hit or miss in the tracking arrays and increments the call count.
+             * Records the hit or miss in the tracking arrays and
-       * @param {boolean} hit true records a hit, false records a miss
+             * increments the call count.
+             * @param {boolean} hit true records a hit, false records a
+             * miss
              */
             this.recordHit = function (hit) {
                 this.recordHitInArray(this.hitsLast100, hit);
@@ -664,6 +743,13 @@ function ApiCache() {
 
         performanceArray.push(perf);
 
+        /**
+         * Cache a request
+         * @param {Object} req Express request object
+         * @param {Object} res Express response object
+         * @param {function} next Function to call next
+         * @returns {any}
+         */
         let cache = function (req, res, next) {
             function bypass() {
                 debug("bypass detected, skipping cache.");
@@ -771,6 +857,11 @@ function ApiCache() {
         return cache;
     };
 
+    /**
+     * Process options
+     * @param {Object} options 
+     * @returns {Object}
+     */
     this.options = function (options) {
         if (options) {
             Object.assign(globalOptions, options);
@@ -791,6 +882,7 @@ function ApiCache() {
         }
     };
 
+    /** Reset the index */
     this.resetIndex = function () {
         index = {
             all: [],
@@ -798,6 +890,11 @@ function ApiCache() {
         };
     };
 
+    /**
+     * Create a new instance of ApiCache
+     * @param {Object} config Config to pass
+     * @returns {ApiCache}
+     */
     this.newInstance = function (config) {
         let instance = new ApiCache();
 
@@ -808,6 +905,7 @@ function ApiCache() {
         return instance;
     };
 
+    /** Clone this instance */
     this.clone = function () {
         return this.newInstance(this.options());
     };

server/modules/apicache/memory-cache.js

@@ -3,6 +3,15 @@ function MemoryCache() {
     this.size = 0;
 }
 
+/**
+ * 
+ * @param {string} key Key to store cache as
+ * @param {any} value Value to store
+ * @param {number} time Time to store for
+ * @param {function(any, string)} timeoutCallback Callback to call in
+ * case of timeout
+ * @returns {Object}
+ */
 MemoryCache.prototype.add = function (key, value, time, timeoutCallback) {
     let old = this.cache[key];
     let instance = this;
@@ -22,6 +31,11 @@ MemoryCache.prototype.add = function (key, value, time, timeoutCallback) {
     return entry;
 };
 
+/**
+ * Delete a cache entry
+ * @param {string} key Key to delete
+ * @returns {null}
+ */
 MemoryCache.prototype.delete = function (key) {
     let entry = this.cache[key];
 
@@ -36,18 +50,32 @@ MemoryCache.prototype.delete = function (key) {
     return null;
 };
 
+/**
+ * Get value of key
+ * @param {string} key 
+ * @returns {Object}
+ */
 MemoryCache.prototype.get = function (key) {
     let entry = this.cache[key];
 
     return entry;
 };
 
+/**
+ * Get value of cache entry
+ * @param {string} key 
+ * @returns {any}
+ */
 MemoryCache.prototype.getValue = function (key) {
     let entry = this.get(key);
 
     return entry && entry.value;
 };
 
+/**
+ * Clear cache
+ * @returns {boolean}
+ */
 MemoryCache.prototype.clear = function () {
     Object.keys(this.cache).forEach(function (key) {
         this.delete(key);