Struct MiddlewareChain 

pub struct MiddlewareChain { /* private fields */ }

Chain of middleware handlers (legacy).

Examples

use pmcp::shared::{MiddlewareChain, LoggingMiddleware, AuthMiddleware, RetryMiddleware};
use pmcp::types::{JSONRPCRequest, JSONRPCResponse, RequestId};
use std::sync::Arc;
use tracing::Level;

// Create a middleware chain
let mut chain = MiddlewareChain::new();

// Add different types of middleware in order
chain.add(Arc::new(LoggingMiddleware::new(Level::INFO)));
chain.add(Arc::new(AuthMiddleware::new("Bearer token-123".to_string())));
chain.add(Arc::new(RetryMiddleware::default()));

// Create a request to process
let mut request = JSONRPCRequest {
    jsonrpc: "2.0".to_string(),
    method: "prompts.get".to_string(),
    params: Some(serde_json::json!({
        "name": "code_review",
        "arguments": {"language": "rust", "style": "detailed"}
    })),
    id: RequestId::from(1001i64),
};

// Process request through all middleware in order
chain.process_request(&mut request).await?;

// Create a response to process
let mut response = JSONRPCResponse {
    jsonrpc: "2.0".to_string(),
    id: RequestId::from(1001i64),
    payload: pmcp::types::jsonrpc::ResponsePayload::Result(
        serde_json::json!({"prompt": "Review the following code..."})
    ),
};

// Process response through all middleware
chain.process_response(&mut response).await?;

// The chain processes middleware in the order they were added
// 1. LoggingMiddleware logs the request/response
// 2. AuthMiddleware adds authentication
// 3. RetryMiddleware configures retry behavior

Implementations

impl MiddlewareChain

pub fn new() -> Self

Create a new empty middleware chain.

pub fn add(&mut self, middleware: Arc<dyn Middleware>)

Add a middleware to the chain.

pub async fn process_request(&self, request: &mut JSONRPCRequest) -> Result<()>

Process a request through all middleware.

pub async fn process_response( &self, response: &mut JSONRPCResponse, ) -> Result<()>

Process a response through all middleware.

pub async fn process_send(&self, message: &TransportMessage) -> Result<()>

Process an outgoing message through all middleware.

pub async fn process_receive(&self, message: &TransportMessage) -> Result<()>

Process an incoming message through all middleware.

Trait Implementations

impl Debug for MiddlewareChain

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for MiddlewareChain

fn default() -> Self

Returns the “default value” for a type.