nocca
Version:
NodeJS Mock Server
321 lines (207 loc) • 8.73 kB
JavaScript
;
var $utils = require('../../utils');
module.exports = {
interface: 'cacheRepository',
id: 'cacheQueue',
name: 'Cache Queue Repository',
description: 'Ordered list of caches, selects first matching cache entry for playback, removes cache entry on hit, allows skipping caches',
constructor: CacheQueue
};
function CacheQueue (Nocca) {
var caches = {
cacheKeys: {},
caches: {}
};
var cacheLists = {};
var recordedCaches = [];
var self = this;
self.logger = Nocca.logger.child({ module: module.exports.id });
var parentLogger = self.logger;
self.invoke = invoke;
self.setCaches = setCaches;
self.considerRecording = considerRecording;
self.matchRequest = matchRequest;
// initialize plugin when Nocca says it's ok to do so
if (!Nocca.initialized) {
Nocca.pubsub.subscribe(Nocca.constants.PUBSUB_NOCCA_INITIALIZE_PLUGIN, _init);
}
else {
_init();
}
// listen for publications with caches
Nocca.pubsub.subscribe('CACHE_QUEUE_SET_CACHES', self.setCaches);
function invoke () {
return self;
}
function _init () {
// add routes
var routes = [
// remove all cacheList sessions
['DELETE:/plugins/cacheQueue/caches', apiDeleteCaches, 'Empties playback caches'],
// feed caches
['PUT:/plugins/cacheQueue/caches', apiSetCaches, 'Replace playback caches (expects array of caches)'],
// feed caches
['GET:/plugins/cacheQueue/caches', apiGetCaches, 'Get current state of playback caches'],
// export recorded caches
['GET:/plugins/cacheQueue/recorded-caches', apiGetRecordedCaches, 'Get contents of current recording session']
];
routes.forEach(function (routeConfig) {
Nocca.pubsub.publish(Nocca.constants.PUBSUB_REST_ROUTE_ADDED, routeConfig);
});
}
function setCaches (cacheArray) {
if (typeof cacheArray === 'string') {
// try json parsing it
cacheArray = JSON.parse(cacheArray);
}
if (Array.isArray(cacheArray)) {
// redefining caches means removing all cacheLists, so do that first
Object.keys(cacheLists).forEach(function (sessionId) {
delete cacheLists[sessionId];
});
// also reset the current caches obj
caches = {
cacheKeys: {},
caches: {}
};
// then parse and reassign caches
cacheArray.forEach(function (cache) {
var cacheKey = generateCacheQueueKey(cache.endpointKey, cache.requestKey);
// register cacheKey if not yet registered
caches.cacheKeys[cacheKey] = caches.cacheKeys[cacheKey] || 0;
// and increment count to indicate cache length
caches.cacheKeys[cacheKey]++;
// register the cache using a numbered cacheKey
var numberedCacheKey = cacheKey + '#' + caches.cacheKeys[cacheKey];
caches.caches[numberedCacheKey] = cache;
});
self.logger.info('Cache queue filled with ' + cacheArray.length + ' caches');
}
else {
throw 'setCaches() should be called with an array, got ' + (typeof cacheArray);
}
}
function considerRecording (reqContext) {
// reserve a spot in the caches
var i = recordedCaches.push({}) - 1;
// always recording, so always extracting the cache
return Nocca.usePlugin(reqContext.config.cacheExtractor)(reqContext)
.then(function (cache) {
self.logger.info('Recorded cache');
// fill reserved spot
recordedCaches[i] = cache;
return reqContext;
});
}
function matchRequest (reqContext) {
// get a relevant cacheList
var cacheList = _getCacheList(reqContext);
// get and consume a cache from the list, if present
var cache = cacheList.consume(reqContext);
// when found, parse to httpMessage format
if (typeof cache !== 'undefined') {
self.logger.info('<<<< Providing cache response');
cache = Nocca.httpMessageFactory.createResponse(cache.playbackResponse);
}
return cache;
}
function _getCacheList (reqContext) {
// allows session dedicated cache list to support loadTesting
var sessionId = '_default';
if (typeof reqContext.config.sessionId !== 'undefined') {
sessionId = reqContext.config.sessionId;
}
// see if sessionId already has a dedicated cacheList
if (typeof cacheLists[sessionId] === 'undefined') {
// no cacheList present, generate on the fly
cacheLists[sessionId] = new CacheList(caches);
}
return cacheLists[sessionId];
}
function generateCacheQueueKey (endpointKey, requestKey) {
return endpointKey + '' + requestKey;
}
function CacheList (caches) {
var self = this;
self.empty = false;
self.repository = {
cacheKeys: {},
steps: {},
caches: {},
hits: 0
};
self.consume = consume;
// parse caches
Object.keys(caches.caches).forEach(function (numberedCacheKey) {
// copy a reference to the actual cache so we can call 'delete' on our object without manipulating the original
self.repository.caches[numberedCacheKey] = caches.caches[numberedCacheKey];
self.repository.steps[numberedCacheKey] = false;
});
function consume (reqContext) {
var cache;
var cacheKey = generateCacheQueueKey(reqContext.endpoint.key, reqContext.requestKey);
// increment count of cacheKey
self.repository.cacheKeys[cacheKey] = self.repository.cacheKeys[cacheKey] || 0;
self.repository.cacheKeys[cacheKey]++;
var numberedCacheKey = cacheKey + '#' + self.repository.cacheKeys[cacheKey];
if (typeof self.repository.caches[numberedCacheKey] !== 'undefined') {
// hit!
self.repository.hits++;
// assign cache
cache = self.repository.caches[numberedCacheKey];
// mark step as hit with hit count
self.repository.steps[numberedCacheKey] = self.repository.hits;
// consume from queue
delete self.repository.caches[numberedCacheKey];
self.empty = Object.keys(self.repository.caches).length === 0;
if (self.empty) {
parentLogger.info('All caches in CacheQueue repository were hit! No caches remaining.');
}
else {
// show progress
var progress = [];
var hits = 0;
Object.keys(self.repository.steps).forEach(function (hit) {
if (self.repository.steps[hit]) {
hits++;
}
progress.push(self.repository.steps[hit] ? '+' : '-');
});
var hitPercentage = 0;
if (hits) {
hitPercentage = Math.round(hits / progress.length * 100);
}
hitPercentage = (' ' + hitPercentage).substr(-3) + '% ';
parentLogger.info(hitPercentage + progress.join('|'));
}
}
return cache;
}
}
// R E S T - A P I F U N C T I O N A L I T Y
function apiGetRecordedCaches (apiReq) {
apiReq.ok().end(recordedCaches);
}
function apiSetCaches (apiReq) {
$utils.readBody(apiReq.req)
.then(function (body) {
var newCaches = JSON.parse(body);
if (Array.isArray(newCaches)) {
self.setCaches(newCaches);
apiReq.ok().end(caches);
}
else {
apiReq.badRequest().end('Payload should be an array of caches');
}
}).fail(function () {
apiReq.badRequest().end('Unable to read request');
});
}
function apiGetCaches (apiReq) {
apiReq.ok().end(cacheLists);
}
function apiDeleteCaches (apiReq) {
setCaches([]);
apiReq.ok().end(caches);
}
}