Struct SessionInjection 

pub struct SessionInjection { /* private fields */ }

Write-only mechanism for middleware to populate session state

Prevents middleware from interfering with core session management while allowing controlled injection of custom state and metadata.

Design

• Write-only: Middleware cannot read existing session state
• Deferred application: Changes applied after all middleware succeed
• Isolation: Each middleware’s changes are independent

Examples

use turul_http_mcp_server::middleware::SessionInjection;
use serde_json::json;

let mut injection = SessionInjection::new();

// Set typed state
injection.set_state("user_id", json!(12345));
injection.set_state("role", json!("admin"));

// Set metadata
injection.set_metadata("authenticated_at", json!("2025-10-04T12:00:00Z"));

// State and metadata are applied to session after middleware succeeds
assert!(!injection.is_empty());

Implementations

impl SessionInjection

pub fn new() -> SessionInjection

Create a new empty session injection

pub fn set_state(&mut self, key: impl Into<String>, value: Value)

Set a state entry

Parameters

• key: State key (used with SessionContext::get_typed_state())
• value: JSON value to store

pub fn set_metadata(&mut self, key: impl Into<String>, value: Value)

Set a metadata entry

Parameters

• key: Metadata key
• value: JSON value to store

pub fn is_empty(&self) -> bool

Check if injection is empty

Trait Implementations

impl Clone for SessionInjection

fn clone(&self) -> SessionInjection

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for SessionInjection

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

Formats the value using the given formatter.

impl Default for SessionInjection

fn default() -> SessionInjection

Returns the “default value” for a type.