TsgcWSPServer_WAMP › Methods › CallProgressResult
Sends an intermediate (progressive) result chunk to the caller while the RPC is still running; subsequent chunks or a final CallResult are expected.
procedure CallProgressResult(const aCallId: String; const aResult: String = '');| Name | Type | Description |
|---|---|---|
aCallId | const String | Identifier generated by the client when the remote procedure was invoked. The call remains pending after sending a progress chunk, so the same aCallId is reused for every additional chunk and for the final CallResult. |
aResult | const String | Partial payload for this chunk. Any string value is allowed (number, text, JSON fragment, etc.); the caller receives the chunks in the same order they are sent. |
Use this method when a single RPC produces more than one piece of data (streaming responses, paged results, long-running calculations, etc.). Each invocation writes a WAMP CALL_PROGRESS_RESULT frame to the caller but, unlike CallResult, it does not remove the call from the pending list: the server must eventually finish the exchange by calling CallResult (success) or CallError (failure) with the same aCallId. If aCallId does not correspond to a pending call the method silently does nothing. Example: for a procedure that yields 20 items, send items 1..19 with CallProgressResult and item 20 with CallResult.
procedure TForm1.sgcWSPServer_WAMP1Call(Connection: TsgcWSConnection;
const CallId, ProcURI: string; Arguments: TStringList);
var
i: Integer;
begin
if ProcURI = 'com.example.stream' then
begin
for i := 1 to 19 do
sgcWSPServer_WAMP1.CallProgressResult(CallId, IntToStr(i));
sgcWSPServer_WAMP1.CallResult(CallId, '20');
end;
end;