Struct PluginContext 

pub struct PluginContext { /* private fields */ }

Available on crate feature plugin only.

A type-safe, concurrent key-value store for plugin shared state.

Uses the TypeMap pattern where each type serves as its own key. Thread-safe via tokio::sync::RwLock for concurrent async access.

Concurrency

• Multiple readers can access state concurrently via get and contains.
• Writers acquire exclusive access via insert and remove.
• No locks are held across await points — each method acquires and releases the lock within a single operation.

Examples

use adk_plugin::PluginContext;

#[derive(Clone, Debug)]
struct RateLimitState {
    requests_this_minute: u32,
}

let ctx = PluginContext::new();

// A rate-limiting plugin writes state
ctx.insert(RateLimitState { requests_this_minute: 1 }).await;

// A metrics plugin reads it
if let Some(state) = ctx.get::<RateLimitState>().await {
    println!("Requests: {}", state.requests_this_minute);
}

Implementations

impl PluginContext

pub fn new() -> PluginContext

Creates a new empty PluginContext.

Examples

use adk_plugin::PluginContext;

let ctx = PluginContext::new();

pub async fn insert<T>(&self, value: T)

where T: Send + Sync + 'static,

Inserts a value into the context. The type itself is the key.

If a value of the same type already exists, it is replaced. The previous value is discarded.

Examples

use adk_plugin::PluginContext;

#[derive(Clone, Debug, PartialEq)]
struct Counter(u32);

let ctx = PluginContext::new();
ctx.insert(Counter(1)).await;
ctx.insert(Counter(2)).await; // Replaces the previous value

assert_eq!(ctx.get::<Counter>().await, Some(Counter(2)));

pub async fn get<T>(&self) -> Option<T>

where T: Clone + Send + Sync + 'static,

Gets a clone of the stored value for type T.

Returns None if no value of type T has been inserted.

Examples

use adk_plugin::PluginContext;

#[derive(Clone, Debug, PartialEq)]
struct Name(String);

let ctx = PluginContext::new();

assert_eq!(ctx.get::<Name>().await, None);

ctx.insert(Name("alice".to_string())).await;
assert_eq!(ctx.get::<Name>().await, Some(Name("alice".to_string())));

pub async fn contains<T>(&self) -> bool

where T: Send + Sync + 'static,

Checks if a value of type T exists in the context.

Examples

use adk_plugin::PluginContext;

#[derive(Clone, Debug)]
struct Marker;

let ctx = PluginContext::new();

assert!(!ctx.contains::<Marker>().await);
ctx.insert(Marker).await;
assert!(ctx.contains::<Marker>().await);

pub async fn remove<T>(&self) -> Option<T>

where T: Send + Sync + 'static,

Removes a value of type T, returning it if present.

After removal, get and contains for type T will return None and false respectively.

Examples

use adk_plugin::PluginContext;

#[derive(Clone, Debug, PartialEq)]
struct Token(String);

let ctx = PluginContext::new();
ctx.insert(Token("abc".to_string())).await;

let removed = ctx.remove::<Token>().await;
assert_eq!(removed, Some(Token("abc".to_string())));
assert_eq!(ctx.get::<Token>().await, None);

Trait Implementations

impl Default for PluginContext

fn default() -> PluginContext

Returns the “default value” for a type.