# Additional Streams Specialized stream types for caching, recording, and broadcasting data operations. ## CacheStream Use `CacheStream` for performance optimization with frequently accessed data. `CacheStream` maintain a cache to reduce calls to the underlying stream. It increases the performance when there are too many data to read/write, or when the same part of the data needs to be modified repeatly. ### CacheStream Capabilities `CacheStream` inherits the capabilities of its underlying stream: - Readable when the underlying stream is readable - Writable when the underlying stream is writable - Seekable when the underlying stream is seekable - Limited/finite when the underlying stream is limited/finite ### Use Cases CacheStream is particularly useful for: - Random access patterns on large files - Repeated reading/writing of the same data sections - Reducing I/O operations on slow storage devices - Optimizing performance when working with network streams ## RecorderStream Use `RecorderStream` for copying data from one stream to another during reading. `RecorderStream` reads data from one readable stream while copying everything to another writable stream. ### RecorderStream Behavior - It is a read-only stream that wraps another readable stream - Every read operation is simultaneously written to a target stream - Useful for creating backups or logs of data as it's being processed - The recorded data can be written to any writable stream (file, memory, etc.) ### Use Cases RecorderStream is ideal for: - Creating audit trails of data processing - Simultaneous backup during data migration - Logging network communications - Splitting data streams for parallel processing ## BroadcastStream Use `BroadcastStream` for writing the same data to multiple target streams. `BroadcastStream` write the same data to multiple streams, which is managed by the `Targets()` method. ### Managing Broadcast Targets Use `Targets()` method to manage BroadcastStream destinations. The `Targets()` method returns a collection that allows you to: - Add new target streams for broadcasting - Remove existing target streams - Query the current list of active targets ### BroadcastStream Behavior - It is a write-only stream that distributes writes to multiple targets - Each write operation is replicated to all registered target streams - If any target stream fails, the broadcast operation may fail - All target streams should be writable for proper operation ### Use Cases BroadcastStream is useful for: - Creating multiple backup copies simultaneously - Writing to both file and network destinations - Distributing data to multiple processing pipelines - Creating redundant storage for critical data ## Extra Content ### Stream Combination Patterns These additional streams can be combined with basic streams and encoding streams to create sophisticated data processing pipelines: 1. **Cached File Processing**: `CacheStream` wrapping a `FileStream` for improved random access performance 2. **Recorded Encoding**: `RecorderStream` capturing the output of an `EncoderStream` for debugging 3. **Broadcast with Compression**: `BroadcastStream` sending data to both compressed and uncompressed destinations ### Performance Considerations - **CacheStream**: Trades memory usage for reduced I/O operations - **RecorderStream**: Doubles the write operations but provides valuable audit capabilities - **BroadcastStream**: Multiplies write operations by the number of targets ### Error Handling Each specialized stream type has specific error scenarios: - **CacheStream**: May fail if the underlying stream becomes unavailable - **RecorderStream**: Can fail if either the source or target stream has issues - **BroadcastStream**: May partially succeed if only some target streams fail ### Memory Management - **CacheStream**: Automatically manages cache size and eviction policies - **RecorderStream**: Doesn't store data itself, just passes it through - **BroadcastStream**: Minimal memory overhead as it doesn't buffer data ### Thread Safety These stream types inherit the thread safety characteristics of their underlying streams. Additional synchronization may be needed when using them in multi-threaded scenarios, especially with `BroadcastStream` where multiple targets might be accessed concurrently.