Overview of the server library

The server library implements specialized Rust server nodes for media, text, and chat handling in a packet-based networked system. It integrates with wg_internal for networking and common for shared utilities, using channels for inter-thread communication and a routing handler for message routing.

Provides three server types:

• MediaServer: Stores and serves media files (e.g., images) via UUID-indexed HashMap.
• TextServer: Manages text files with content and media references.
• ChatServer: Handles client registration and message forwarding.

All servers implement the Processor trait for packet processing, command handling, and event notifications.

Features

• Modular servers with shared Processor logic for commands, packets, and fragmentation.
• In-memory storage: HashMap for files (UUID keys), HashSet for chat clients.
• Request handling: Deserializes JSON requests (e.g., WebRequest, ChatRequest) and responds via routing.
• Command system: Supports node operations (add/remove neighbors, shutdown) and server-specific actions (add/remove files, get lists).
• Error management: Handles invalid UUIDs, missing files, malformed messages.
• File conversion: Uses common::file_conversion for path-to-file imports.
• Testing: Unit tests cover creation, operations, requests, and edge cases (e.g., large files, invalid inputs).

Architecture

Core Components

• Processor Trait: Interface for receivers (commands, packets), assembler, routing handler, message/command handling.
• RoutingHandler: Manages neighbors and message sending.
• FragmentAssembler: Reassembles packet fragments.
• Types: From common::types, includes commands/events (e.g., NodeCommand, WebEvent), requests/responses.
• Common Commands (NodeCommand): Handled by all servers.
  • AddSender(node_id, sender): Adds a neighbor to the routing handler.
  • RemoveSender(node_id): Removes a neighbor from the routing handler.
  • Shutdown: Signals termination (returns true to exit processing loop).

Server Details

MediaServer

• Storage: HashMap<Uuid, MediaFile> (title, chunked content).
• Requests (WebRequest variants):
  • ServerTypeQuery: Responds with WebResponse::ServerType { server_type: ServerType::MediaServer }; sends event NodeEvent::ServerTypeQueried.
  • MediaQuery { media_id }: Parses UUID, retrieves and serializes media file if found, responds with WebResponse::MediaFile { media_data: ... } and event WebEvent::FileServed; or WebResponse::ErrorFileNotFound if missing; or WebResponse::BadUuid if invalid (with event WebEvent::BadUuid).
• Commands (WebCommand variants):
  • GetMediaFiles: Retrieves all media files, sends event WebEvent::MediaFiles { files: ... }.
  • GetMediaFile { media_id, location: _ }: Retrieves specific media file if found, sends event WebEvent::MediaFile { file: ... }.
  • AddMediaFile(media_file): Adds file to storage, sends event WebEvent::MediaFileAdded { uuid: ... }.
  • AddMediaFileFromPath(file_path): Converts path to media file, adds if successful (sends MediaFileAdded), or sends WebEvent::FileOperationError on failure.
  • RemoveMediaFile(uuid): Removes file if found (sends WebEvent::MediaFileRemoved { uuid: ... }), or sends FileOperationError if missing.

TextServer

• Storage: HashMap<Uuid, TextFile> (title, content, media refs).
• Requests (WebRequest variants):
  • ServerTypeQuery: Responds with WebResponse::ServerType { server_type: ServerType::TextServer }; sends event NodeEvent::ServerTypeQueried.
  • TextFilesListQuery: Retrieves formatted list ("UUID:title"), responds with WebResponse::TextFilesList { files: ... }; sends event WebEvent::FilesListQueried.
  • FileQuery { file_id }: Parses UUID, retrieves and serializes text file if found, responds with WebResponse::TextFile { file_data: ... } and event WebEvent::FileServed; or WebResponse::ErrorFileNotFound if missing; or WebResponse::BadUuid if invalid (with event WebEvent::BadUuid).
• Commands (WebCommand variants):
  • GetTextFiles: Retrieves all text files, sends event WebEvent::TextFiles { files: ... }.
  • GetTextFile(uuid): Retrieves specific text file if found, sends event WebEvent::TextFile { file: ... }.
  • AddTextFile(text_file): Adds file to storage, sends event WebEvent::TextFileAdded { uuid: ... }.
  • AddTextFileFromPath(file_path): Converts path to text file, adds if successful (sends TextFileAdded), or sends WebEvent::FileOperationError on failure.
  • RemoveTextFile(uuid): Removes file if found (sends WebEvent::TextFileRemoved { uuid: ... }), or sends FileOperationError if missing.

ChatServer

• Storage: HashSet<NodeId> for clients.
• Requests (ChatRequest variants):
  • ServerTypeQuery: Responds with ChatResponse::ServerType { server_type: ServerType::ChatServer }; sends event NodeEvent::ServerTypeQueried.
  • RegistrationToChat { client_id }: Registers client, responds with ChatResponse::RegistrationSuccess; sends event ChatEvent::ClientRegistered.
  • ClientListQuery: Retrieves registered client IDs, responds with ChatResponse::ClientList { list_of_client_ids: ... }; sends event ChatEvent::ClientListQueried.
  • MessageFor { client_id, message }: If target registered, forwards ChatResponse::MessageFrom { client_id: from, message } to target; else responds with ChatResponse::ErrorWrongClientId.
• Commands (ChatCommand variants):
  • GetRegisteredClients: Retrieves registered client IDs, sends event ChatEvent::RegisteredClients { list: ... }.