Struct NodeAppContext 

#[repr(C)]
pub struct NodeAppContext {
    pub host_data: *const c_void,
    pub host_log: unsafe extern "C" fn(host_data: *const c_void, level: u32, message: *const c_char),
    pub host_get_config: unsafe extern "C" fn(host_data: *const c_void, key: *const c_char) -> *const c_char,
    pub host_set_storage: unsafe extern "C" fn(host_data: *const c_void, key: *const c_char, value: *const c_char),
    pub host_get_storage: unsafe extern "C" fn(host_data: *const c_void, key: *const c_char) -> *const c_char,
    pub host_invoke_capability: unsafe extern "C" fn(host_data: *const c_void, request_json: *const u8, request_len: usize) -> FfiResult,
    pub host_publish_event: unsafe extern "C" fn(host_data: *const c_void, event_name: *const u8, event_name_len: usize, event_data: *const u8, event_data_len: usize) -> i32,
}

Host context provided to native apps.

Contains function pointers for callbacks into the host. The context pointer is valid for the lifetime of the app.

Fields

host_data: *const c_void

Opaque pointer to host-side state (passed as first arg to callbacks)

host_log: unsafe extern "C" fn(host_data: *const c_void, level: u32, message: *const c_char)

Log a message at the specified level. level: 0=trace, 1=debug, 2=info, 3=warn, 4=error message: null-terminated UTF-8 string

host_get_config: unsafe extern "C" fn(host_data: *const c_void, key: *const c_char) -> *const c_char

Get a configuration value by key. Returns null if key not found. Caller must NOT free the returned pointer.

host_set_storage: unsafe extern "C" fn(host_data: *const c_void, key: *const c_char, value: *const c_char)

Set a storage value (scoped to this app). Both key and value are null-terminated UTF-8 strings.

host_get_storage: unsafe extern "C" fn(host_data: *const c_void, key: *const c_char) -> *const c_char

Get a storage value by key (scoped to this app). Returns null if key not found. Caller must NOT free the returned pointer.

host_invoke_capability: unsafe extern "C" fn(host_data: *const c_void, request_json: *const u8, request_len: usize) -> FfiResult

Invoke a capability on the host via the capability router. request_json is a pointer to UTF-8 JSON bytes (CapabilityRequest) of length request_len. Returns FfiResult with CapabilityResponse JSON in data/data_len. The caller must free the returned data using the host’s free function.

host_publish_event: unsafe extern "C" fn(host_data: *const c_void, event_name: *const u8, event_name_len: usize, event_data: *const u8, event_data_len: usize) -> i32

Publish a domain event to the host event bus. event_name is a pointer to UTF-8 bytes of length event_name_len (max 256 bytes). event_data is a pointer to UTF-8 JSON bytes of length event_data_len (max 64KB). Returns 0 on success, negative error code on failure. Fire-and-forget semantics: the event is queued asynchronously.