| var path = require('path'); | |
| var crypto = require('crypto'); | |
| 
 | |
| module.exports = { | |
|   createFromFile: function (filePath, useChecksum) { | |
|     var fname = path.basename(filePath); | |
|     var dir = path.dirname(filePath); | |
|     return this.create(fname, dir, useChecksum); | |
|   }, | |
| 
 | |
|   create: function (cacheId, _path, useChecksum) { | |
|     var fs = require('fs'); | |
|     var flatCache = require('flat-cache'); | |
|     var cache = flatCache.load(cacheId, _path); | |
|     var normalizedEntries = {}; | |
| 
 | |
|     var removeNotFoundFiles = function removeNotFoundFiles() { | |
|       const cachedEntries = cache.keys(); | |
|       // remove not found entries | |
|       cachedEntries.forEach(function remover(fPath) { | |
|         try { | |
|           fs.statSync(fPath); | |
|         } catch (err) { | |
|           if (err.code === 'ENOENT') { | |
|             cache.removeKey(fPath); | |
|           } | |
|         } | |
|       }); | |
|     }; | |
| 
 | |
|     removeNotFoundFiles(); | |
| 
 | |
|     return { | |
|       /** | |
|        * the flat cache storage used to persist the metadata of the `files | |
|        * @type {Object} | |
|        */ | |
|       cache: cache, | |
| 
 | |
|       /** | |
|        * Given a buffer, calculate md5 hash of its content. | |
|        * @method getHash | |
|        * @param  {Buffer} buffer   buffer to calculate hash on | |
|        * @return {String}          content hash digest | |
|        */ | |
|       getHash: function (buffer) { | |
|         return crypto.createHash('md5').update(buffer).digest('hex'); | |
|       }, | |
| 
 | |
|       /** | |
|        * Return whether or not a file has changed since last time reconcile was called. | |
|        * @method hasFileChanged | |
|        * @param  {String}  file  the filepath to check | |
|        * @return {Boolean}       wheter or not the file has changed | |
|        */ | |
|       hasFileChanged: function (file) { | |
|         return this.getFileDescriptor(file).changed; | |
|       }, | |
| 
 | |
|       /** | |
|        * given an array of file paths it return and object with three arrays: | |
|        *  - changedFiles: Files that changed since previous run | |
|        *  - notChangedFiles: Files that haven't change | |
|        *  - notFoundFiles: Files that were not found, probably deleted | |
|        * | |
|        * @param  {Array} files the files to analyze and compare to the previous seen files | |
|        * @return {[type]}       [description] | |
|        */ | |
|       analyzeFiles: function (files) { | |
|         var me = this; | |
|         files = files || []; | |
| 
 | |
|         var res = { | |
|           changedFiles: [], | |
|           notFoundFiles: [], | |
|           notChangedFiles: [], | |
|         }; | |
| 
 | |
|         me.normalizeEntries(files).forEach(function (entry) { | |
|           if (entry.changed) { | |
|             res.changedFiles.push(entry.key); | |
|             return; | |
|           } | |
|           if (entry.notFound) { | |
|             res.notFoundFiles.push(entry.key); | |
|             return; | |
|           } | |
|           res.notChangedFiles.push(entry.key); | |
|         }); | |
|         return res; | |
|       }, | |
| 
 | |
|       getFileDescriptor: function (file) { | |
|         var fstat; | |
| 
 | |
|         try { | |
|           fstat = fs.statSync(file); | |
|         } catch (ex) { | |
|           this.removeEntry(file); | |
|           return { key: file, notFound: true, err: ex }; | |
|         } | |
| 
 | |
|         if (useChecksum) { | |
|           return this._getFileDescriptorUsingChecksum(file); | |
|         } | |
| 
 | |
|         return this._getFileDescriptorUsingMtimeAndSize(file, fstat); | |
|       }, | |
| 
 | |
|       _getFileDescriptorUsingMtimeAndSize: function (file, fstat) { | |
|         var meta = cache.getKey(file); | |
|         var cacheExists = !!meta; | |
| 
 | |
|         var cSize = fstat.size; | |
|         var cTime = fstat.mtime.getTime(); | |
| 
 | |
|         var isDifferentDate; | |
|         var isDifferentSize; | |
| 
 | |
|         if (!meta) { | |
|           meta = { size: cSize, mtime: cTime }; | |
|         } else { | |
|           isDifferentDate = cTime !== meta.mtime; | |
|           isDifferentSize = cSize !== meta.size; | |
|         } | |
| 
 | |
|         var nEntry = (normalizedEntries[file] = { | |
|           key: file, | |
|           changed: !cacheExists || isDifferentDate || isDifferentSize, | |
|           meta: meta, | |
|         }); | |
| 
 | |
|         return nEntry; | |
|       }, | |
| 
 | |
|       _getFileDescriptorUsingChecksum: function (file) { | |
|         var meta = cache.getKey(file); | |
|         var cacheExists = !!meta; | |
| 
 | |
|         var contentBuffer; | |
|         try { | |
|           contentBuffer = fs.readFileSync(file); | |
|         } catch (ex) { | |
|           contentBuffer = ''; | |
|         } | |
| 
 | |
|         var isDifferent = true; | |
|         var hash = this.getHash(contentBuffer); | |
| 
 | |
|         if (!meta) { | |
|           meta = { hash: hash }; | |
|         } else { | |
|           isDifferent = hash !== meta.hash; | |
|         } | |
| 
 | |
|         var nEntry = (normalizedEntries[file] = { | |
|           key: file, | |
|           changed: !cacheExists || isDifferent, | |
|           meta: meta, | |
|         }); | |
| 
 | |
|         return nEntry; | |
|       }, | |
| 
 | |
|       /** | |
|        * Return the list o the files that changed compared | |
|        * against the ones stored in the cache | |
|        * | |
|        * @method getUpdated | |
|        * @param files {Array} the array of files to compare against the ones in the cache | |
|        * @returns {Array} | |
|        */ | |
|       getUpdatedFiles: function (files) { | |
|         var me = this; | |
|         files = files || []; | |
| 
 | |
|         return me | |
|           .normalizeEntries(files) | |
|           .filter(function (entry) { | |
|             return entry.changed; | |
|           }) | |
|           .map(function (entry) { | |
|             return entry.key; | |
|           }); | |
|       }, | |
| 
 | |
|       /** | |
|        * return the list of files | |
|        * @method normalizeEntries | |
|        * @param files | |
|        * @returns {*} | |
|        */ | |
|       normalizeEntries: function (files) { | |
|         files = files || []; | |
| 
 | |
|         var me = this; | |
|         var nEntries = files.map(function (file) { | |
|           return me.getFileDescriptor(file); | |
|         }); | |
| 
 | |
|         //normalizeEntries = nEntries; | |
|         return nEntries; | |
|       }, | |
| 
 | |
|       /** | |
|        * Remove an entry from the file-entry-cache. Useful to force the file to still be considered | |
|        * modified the next time the process is run | |
|        * | |
|        * @method removeEntry | |
|        * @param entryName | |
|        */ | |
|       removeEntry: function (entryName) { | |
|         delete normalizedEntries[entryName]; | |
|         cache.removeKey(entryName); | |
|       }, | |
| 
 | |
|       /** | |
|        * Delete the cache file from the disk | |
|        * @method deleteCacheFile | |
|        */ | |
|       deleteCacheFile: function () { | |
|         cache.removeCacheFile(); | |
|       }, | |
| 
 | |
|       /** | |
|        * remove the cache from the file and clear the memory cache | |
|        */ | |
|       destroy: function () { | |
|         normalizedEntries = {}; | |
|         cache.destroy(); | |
|       }, | |
| 
 | |
|       _getMetaForFileUsingCheckSum: function (cacheEntry) { | |
|         var contentBuffer = fs.readFileSync(cacheEntry.key); | |
|         var hash = this.getHash(contentBuffer); | |
|         var meta = Object.assign(cacheEntry.meta, { hash: hash }); | |
|         delete meta.size; | |
|         delete meta.mtime; | |
|         return meta; | |
|       }, | |
| 
 | |
|       _getMetaForFileUsingMtimeAndSize: function (cacheEntry) { | |
|         var stat = fs.statSync(cacheEntry.key); | |
|         var meta = Object.assign(cacheEntry.meta, { | |
|           size: stat.size, | |
|           mtime: stat.mtime.getTime(), | |
|         }); | |
|         delete meta.hash; | |
|         return meta; | |
|       }, | |
| 
 | |
|       /** | |
|        * Sync the files and persist them to the cache | |
|        * @method reconcile | |
|        */ | |
|       reconcile: function (noPrune) { | |
|         removeNotFoundFiles(); | |
| 
 | |
|         noPrune = typeof noPrune === 'undefined' ? true : noPrune; | |
| 
 | |
|         var entries = normalizedEntries; | |
|         var keys = Object.keys(entries); | |
| 
 | |
|         if (keys.length === 0) { | |
|           return; | |
|         } | |
| 
 | |
|         var me = this; | |
| 
 | |
|         keys.forEach(function (entryName) { | |
|           var cacheEntry = entries[entryName]; | |
| 
 | |
|           try { | |
|             var meta = useChecksum | |
|               ? me._getMetaForFileUsingCheckSum(cacheEntry) | |
|               : me._getMetaForFileUsingMtimeAndSize(cacheEntry); | |
|             cache.setKey(entryName, meta); | |
|           } catch (err) { | |
|             // if the file does not exists we don't save it | |
|             // other errors are just thrown | |
|             if (err.code !== 'ENOENT') { | |
|               throw err; | |
|             } | |
|           } | |
|         }); | |
| 
 | |
|         cache.save(noPrune); | |
|       }, | |
|     }; | |
|   }, | |
| };
 |