Struct FunctionObserver 

pub struct FunctionObserver { /* private fields */ }

Executes functions in response to trigger events.

This observer integrates with the fraiseql-observers action execution pipeline. It receives trigger events, looks up the corresponding function module, selects the appropriate runtime, and executes the function.

Implementations

impl FunctionObserver

pub fn new() -> Self

Create a new function observer.

pub fn register_runtime<R: FunctionRuntime + 'static>( &mut self, runtime_type: RuntimeType, runtime: R, )

Register a runtime for a specific runtime type.

Errors

Returns Err if runtime registration fails.

pub async fn invoke<H>( &self, module: &FunctionModule, event: EventPayload, host: &H, limits: ResourceLimits, ) -> Result<FunctionResult>

where H: HostContext + ?Sized,

Execute a function module in response to an event.

Dispatches to the appropriate runtime based on the module’s runtime field.

Errors

Returns Err if:

• No runtime is registered for the module’s runtime type
• The runtime fails to execute the module

pub fn find_after_mutation_triggers( &self, registry: &TriggerRegistry, event: &EntityEvent, ) -> Vec<AfterMutationTrigger>

Find all after:mutation triggers that match a given entity event.

Returns the list of matching AfterMutationTriggers from registry. Used by after-mutation dispatchers to know which functions to invoke. This method is allocation-free when no triggers match.

pub fn find_after_capture_triggers( &self, registry: &TriggerRegistry, event: &EntityEvent, ) -> Vec<AfterMutationTrigger>

Find after:capture triggers (#366) matching an externally-captured change.

The change-log reader calls this for captured rows; the match is on entity + event kind, same as after:mutation, but against the separate capture matcher.

pub async fn invoke_with_context( &self, module: &FunctionModule, event: EventPayload, host: Arc<dyn DynHostContext>, limits: ResourceLimits, ) -> Result<FunctionResult>

Execute a function module with a full I/O-capable host context.

Unlike invoke — which snapshots the host into a sync-only view and so returns Unsupported for async I/O — this routes to the runtime’s invoke_with_context, giving the guest live HTTP / query / storage access through host. The after:mutation dispatcher uses this so side-effecting functions (webhooks, external provisioning, LLM scoring) can reach the network.

Dispatches by the module’s runtime field: WASM modules route to WasmRuntime::invoke_with_context, Deno (JavaScript/TypeScript) modules to DenoRuntime::invoke_with_context. An event whose module targets a runtime that is not compiled in returns Unsupported.

Those two are named in prose rather than linked: this method is not feature-gated (the before:mutation chain calls it from an ungated caller, #1328), so its docs are rendered in a build where neither runtime module exists — and an intra-doc link to an item that is compiled out is a -D warnings rustdoc failure, not a dead link.

Errors

Returns Err if no runtime is registered for the module’s runtime type, the registered runtime is of the wrong concrete type, or guest execution fails.

Trait Implementations

impl Default for FunctionObserver

fn default() -> Self

Returns the “default value” for a type.