wasmbus FFI Functions

For the curious, here is the exact list of the wasmbus protocol’s functions. The guest always imports from a module called wasmbus, and all function names are preceded by two underscores to avoid accidental collisions with other exported functions.

Function	Owner	Description
__console_log	Host	Guest calls host to log to host’s stdout (if permitted)
__host_call	Host	Guest calls to request the host perform an operation
__host_response	Host	Tells the host the pointer address at which to store its response
__host_response_len	Host	Returns the length of the host’s response
__host_error	Host	Tells the host the pointer address at which to store its error blob
__host_error_len	Host	Returns the length of the host error blob
__guest_response	Host	Called by the guest to set the pointer and length of the guest’s response blob
__guest_error	Host	Called by the guest to set the pointer and length of the guest’s error blob
__guest_request	Host	Called by the guest to tell the host the pointer addresses of where to store the request’s operation (string) and request payload (blob) values.
__guest_call	Guest	Invoked by the host to tell the guest to begin processing a function call. The guest will then retrieve the parameters and set response values via host calls.
__wasmbus_rpc_version	Guest	Invoked by the host to query the actor module to determine which version of the wasmbus protocol it was built against. Current actors should return the value 1

The wasmbus FFI functions are already taken care of for you in the existing libraries that are code generated from our smithy schemas. Built on top of our code generation foundation, we have the wasmCloud interfaces.