public CachedIndexOutput(ICloudProvider CloudProvider, Directory CacheDirectory, string Name)
        {
            this.cloudProvider  = CloudProvider;
            this.cacheDirectory = CacheDirectory;
            this.name           = Name;

            this.fileMutex = BlobMutexManager.GrabMutex(this.name);
            this.fileMutex.WaitOne();
            try {
                // create the local cache one we will operate against...
                this.indexOutput = this.cacheDirectory.CreateOutput(this.name);
            } finally {
                this.fileMutex.ReleaseMutex();
            }
        }
Esempio n. 2
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        // ctor for clone
        private CachedIndexInput(CachedIndexInput cloneInput)
        {
            this.name      = cloneInput.name;
            this.fileMutex = BlobMutexManager.GrabMutex(this.name);
            this.fileMutex.WaitOne();

            try {
#if FULLDEBUG
                Debug.WriteLine("Creating clone for " + this.name);
#endif
                this.indexInput = cloneInput.indexInput.Clone() as IndexInput;
                // FRAGILE: ASSUME: File is already downloaded and current
            } catch (Exception) {
                // sometimes we get access denied on the 2nd stream...but not always. I haven't tracked it down yet but this covers our tail until I do
                Debug.WriteLine("Dagnabbit, falling back to memory clone for " + this.name);
            } finally {
                this.fileMutex.ReleaseMutex();
            }
        }
Esempio n. 3
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        public CachedIndexInput(ICloudProvider CloudProvider, Directory CacheDirectory, string Name)
        {
            this.name = Name;

#if FULLDEBUG
            Debug.WriteLine("Opening " + this.name);
#endif
            this.fileMutex = BlobMutexManager.GrabMutex(this.name);
            this.fileMutex.WaitOne();
            try {
                bool         fFileNeeded   = false;
                FileMetadata cloudMetadata = CloudProvider.FileMetadata(this.name);
                if (!cloudMetadata.Exists)
                {
                    fFileNeeded = false;
                    // TODO: Delete local if it doesn't exist on cloud?

                    /*
                     * if (CacheDirectory.FileExists(this.name)) {
                     *      CacheDirectory.DeleteFile(this.name);
                     * }
                     */
                }
                else if (!CacheDirectory.FileExists(this.name))
                {
                    fFileNeeded = true;
                }
                else
                {
                    long cachedLength = CacheDirectory.FileLength(this.name);

                    long     blobLength          = cloudMetadata.Length;
                    DateTime blobLastModifiedUTC = cloudMetadata.LastModified.ToUniversalTime();

                    if (!cloudMetadata.Exists || cachedLength != blobLength)
                    {
                        fFileNeeded = true;
                    }
                    else
                    {
                        // there seems to be an error of 1 tick which happens every once in a while
                        // for now we will say that if they are within 1 tick of each other and same length
                        DateTime cachedLastModifiedUTC = new DateTime(CacheDirectory.FileModified(this.name), DateTimeKind.Local).ToUniversalTime();
                        if (cachedLastModifiedUTC < blobLastModifiedUTC)
                        {
                            TimeSpan timeSpan = blobLastModifiedUTC.Subtract(cachedLastModifiedUTC);
                            if (timeSpan.TotalSeconds > 1)
                            {
                                fFileNeeded = true;
                            }
                            else
                            {
#if FULLDEBUG
                                Debug.WriteLine("Using cache for " + this.name + ": " + timeSpan.TotalSeconds);
#endif
                                // file not needed
                            }
                        }
                    }
                }

                // if the file does not exist
                // or if it exists and it is older then the lastmodified time in the blobproperties (which always comes from the blob storage)
                if (fFileNeeded)
                {
                    using (StreamOutput fileStream = new StreamOutput(CacheDirectory.CreateOutput(this.name))) {
                        Stream blobStream = CloudProvider.Download(this.name);
                        blobStream.CopyTo(fileStream);

                        fileStream.Flush();
                        Debug.WriteLine("GET {0} RETREIVED {1} bytes", this.name, fileStream.Length);
                    }
                }
                else
                {
#if FULLDEBUG
                    if (!cloudMetadata.Exists)
                    {
                        Debug.WriteLine("Cloud doesn't have " + this.name);
                    }
                    else
                    {
                        Debug.WriteLine("Using cached file for " + this.name);
                    }
#endif
                }

                // open the file in read only mode
                this.indexInput = CacheDirectory.OpenInput(this.name);
            } finally {
                this.fileMutex.ReleaseMutex();
            }
        }