sgcHTTP HTTP サーバー、HTTP/2 と gRPC が、 Delphi にネイティブ。 Google Cloud にも対応。

uses
  sgcHTTP;
var
  GRPC: TsgcGRPCClient;
begin
  // gRPC: built on the HTTP/2 client, unary and streaming RPC
  GRPC := TsgcGRPCClient.Create(nil);
  GRPC.Client.Host := 'https://grpc.example.com';
  GRPC.OnGRPCResponse := GRPCResponse;

  GRPC.CallAsync('example.OrderService', 'GetOrder', RequestBytes);
end;

procedure TForm1.GRPCResponse(Sender: TObject;
  const aResponse: TsgcGRPCResponse);
begin
  Memo1.Lines.Add(aResponse.DataString);
end;

uses
  sgcHTTP_Server;
var
  Server: TsgcHTTPServer;
begin
  // HTTP server: endpoints and static files
  Server := TsgcHTTPServer.Create(nil);
  Server.Port := 8080;
  Server.DocumentRoot := 'C:\www';
  Server.OnCommandGet := ServerCommandGet;
  Server.Active := True;
end;

procedure TForm1.ServerCommandGet(AContext: TIdContext;
  ARequestInfo: TIdHTTPRequestInfo;
  AResponseInfo: TIdHTTPResponseInfo);
begin
  if ARequestInfo.Document = '/api/status' then
  begin
    AResponseInfo.ContentType := 'application/json';
    AResponseInfo.ContentText := '{"status":"ok"}';
  end;
end;