Struct PluginContext 

pub struct PluginContext {

    pub request_headers: Vec<(String, String)>,
    pub response_headers: Vec<(String, String)>,
    pub request_body: Vec<u8>,
    pub response_body: Vec<u8>,
    pub plugin_config: Vec<u8>,
    pub vm_config: Vec<u8>,
    pub action: u32,
    pub local_response: Option<LocalResponse>,
    pub logs: Vec<(u32, String)>,
    pub shared_data: Arc<Mutex<SharedData>>,
    pub pending_callouts: Vec<PendingCallout>,
    pub callout_token_counter: u32,
    pub callout_response_headers: Vec<(String, String)>,
    pub callout_response_body: Vec<u8>,
    pub metrics: HashMap<String, PluginMetric>,
    pub current_context_id: u32,
    pub effective_context_id: u32,
    pub done: bool,
    pub memory_used: usize,
    pub memory_cap: usize,
    /* private fields */
}

The per-instance context the host imports read from and write to.

Stored as the wasmtime store’s T type. The host import functions receive a &mut PluginContext via Caller and use it to exchange data with the plugin.

Fields

request_headers: Vec<(String, String)>

Request headers (set by the host before proxy_on_request_headers).

response_headers: Vec<(String, String)>

Response headers (set by the host before proxy_on_response_headers).

request_body: Vec<u8>

Request body (set by the host before proxy_on_request_body).

response_body: Vec<u8>

Response body (set by the host before proxy_on_response_body).

plugin_config: Vec<u8>

Plugin configuration (passed to proxy_on_configure).

vm_config: Vec<u8>

VM configuration (passed to proxy_on_vm_start).

action: u32

The action the plugin returned from the last phase callback.

local_response: Option<LocalResponse>

Whether the plugin has called proxy_send_http_response (a short-circuit response). When set, the host should stop processing and return the stored response.

logs: Vec<(u32, String)>

Log lines emitted by the plugin via proxy_log.

shared_data: Arc<Mutex<SharedData>>

The VM-scoped shared-data store handle (see SharedData).

pending_callouts: Vec<PendingCallout>

Callouts registered by proxy_http_call and not yet answered (DW-167). One instance can queue several; the dispatch driver performs them in FIFO order, one round each.

callout_token_counter: u32

Monotonic callout-token counter (tokens are handed out by the host and delivered back with proxy_on_http_call_response).

callout_response_headers: Vec<(String, String)>

The last delivered callout response’s header map (:status plus ordinary headers, hop-by-hop stripped) — what MapType 6 reads return inside proxy_on_http_call_response.

callout_response_body: Vec<u8>

The last delivered callout response’s body — what BufferType 4 reads return inside proxy_on_http_call_response.

metrics: HashMap<String, PluginMetric>

Metrics registered by the plugin.

current_context_id: u32

The current context ID (set by the host before calling exports).

effective_context_id: u32

The effective context ID (set by proxy_set_effective_context).

done: bool

Whether proxy_done was called.

memory_used: usize

Memory limiter state (tracks current allocation against the cap).

memory_cap: usize

Memory cap in bytes.

Trait Implementations

impl ResourceLimiter for PluginContext

The memory cap for a plugin instance, enforced via wasmtime’s ResourceLimiter trait on the store’s user data (PluginContext).

fn memory_growing( &mut self, _current: usize, desired: usize, _maximum: Option<usize>, ) -> Result<bool>

Notifies the resource limiter that an instance’s linear memory has been requested to grow.

fn table_growing( &mut self, _current: usize, desired: usize, _maximum: Option<usize>, ) -> Result<bool>

Notifies the resource limiter that an instance’s table has been requested to grow.

fn memory_grow_failed(&mut self, error: Error) -> Result<(), Error>

Notifies the resource limiter that growing a linear memory, permitted by the memory_growing method, has failed.

fn table_grow_failed(&mut self, error: Error) -> Result<(), Error>

Notifies the resource limiter that growing a linear memory, permitted by the table_growing method, has failed.

fn instances(&self) -> usize

The maximum number of instances that can be created for a Store.

fn tables(&self) -> usize

The maximum number of tables that can be created for a Store.

fn memories(&self) -> usize

The maximum number of linear memories that can be created for a Store