Pascal (Lazarus/Delphi)

Firebase PUT - Writing Data

See more Firebase Examples

Demonstrates how to PUT new data to a Firebase JSON database. The data used in this example is at Chilkat Firebase Pigs Database, and is shown here:

Pascal (Lazarus/Delphi)

program ChilkatDemo;

// Demonstrates using the Chilkat Pascal wrapper via the C bridge DLL.
// Builds as a console application under Lazarus (FPC) or Delphi.

{$IFDEF FPC}
  {$MODE DELPHI}
{$ENDIF}
{$APPTYPE CONSOLE}

uses
  {$IFDEF UNIX}
  cthreads,
  {$ENDIF}
  SysUtils,
  CkDllLoader,
  Chilkat.AuthGoogle,
  Chilkat.Prng,
  Chilkat.FileAccess,
  Chilkat.Rest,
  Chilkat.JsonObject,
  Chilkat.StringBuilder;

// ---------------------------------------------------------------------------

procedure RunDemo;
var
  success: Boolean;
  fac: TFileAccess;
  accessToken: string;
  rest: TRest;
  authGoogle: TAuthGoogle;
  prng: TPrng;
  pushId: string;
  pigRecord: TJsonObject;
  path: TStringBuilder;
  jsonResponse: string;

begin
  success := False;

  //  Demonstrates how to PUT new data to a Firebase JSON database.

  //  This example requires the Chilkat API to have been previously unlocked.
  //  See Global Unlock Sample for sample code.

  //  This example assumes a JWT authentication token, if required, has been previously obtained.
  //  See Get Firebase Access Token from JSON Service Account Private Key for sample code.

  //  Load the previously obtained Firebase access token into a string.
  fac := TFileAccess.Create;
  accessToken := fac.ReadEntireTextFile('qa_data/tokens/firebaseToken.txt','utf-8');
  if (fac.LastMethodSuccess <> True) then
    begin
      WriteLn(fac.LastErrorText);
      Exit;
    end;

  rest := TRest.Create;

  //  Make the initial connection (without sending a request yet).
  //  Once connected, any number of requests may be sent.  It is not necessary to explicitly
  //  call Connect before each request.  
  success := rest.Connect('chilkat.firebaseio.com',443,True,True);
  if (success <> True) then
    begin
      WriteLn(rest.LastErrorText);
      Exit;
    end;
  authGoogle := TAuthGoogle.Create;
  authGoogle.AccessToken := accessToken;
  rest.SetAuthGoogle(authGoogle);

  //  Chilkat's sample data (pig-rescue data) is publicly readable at: https://chilkat.firebaseio.com/.json
  //  This data is publicly readable, but not writable.  You'll need to 
  //  run against your own database..

  //  Generate a new push ID.
  prng := TPrng.Create;
  pushId := prng.FirebasePushId();

  //  We're going to add a new pig with just the name.
  pigRecord := TJsonObject.Create;
  pigRecord.AppendString('name','William');

  path := TStringBuilder.Create;
  path.Append('/pig-rescue/animal/');
  path.Append(pushId);
  path.Append('.json');

  //  The string content of the last arg passed is  {"name":"William"} 
  jsonResponse := rest.FullRequestString('PUT',path.GetAsString(),pigRecord.Emit());
  if (rest.LastMethodSuccess <> True) then
    begin
      //  Something happened in the communications (either no request was sent, or no response was received.
      //  (The Chilkat REST API also has lower-level methods where an app can send the request in one call,
      //  and then receive the response in another call.)
      WriteLn(rest.LastErrorText);
      Exit;
    end;

  //  Check the response status code.   A 200 response status indicates success.
  if (rest.ResponseStatusCode <> 200) then
    begin
      WriteLn(rest.ResponseStatusText);
      WriteLn(jsonResponse);
      WriteLn('Failed.');
      Exit;
    end;

  WriteLn(jsonResponse);
  WriteLn('Success.');

  //  Note: In many of the Chilkat examples, you may notice strange ways
  //  of doing something that should be simpler and shorter.  For example,
  //  building the path (above) could've been written differently,
  //  with some simple string concatenation.
  //  
  //  The reason is that the Chilkat examples are written in a 
  //  proprietary "example code" scripting language,
  //  and then automatically generated to each of the different programming
  //  languages you see on example-code.com.  The code generation is
  //  limited in what it can do.  For example, string concatentation
  //  is not yet a feature of the "example code" scripting language (as of May 2016), 
  //  and therefore you won't see the use of a programming language's string
  //  concatentation operators in any example.  
  //  


  fac.Free;
  rest.Free;
  authGoogle.Free;
  prng.Free;
  pigRecord.Free;
  path.Free;

end;

// ---------------------------------------------------------------------------

begin

  try
    RunDemo;
  except
    on E: Exception do
      WriteLn('Unhandled exception: ', E.ClassName, ': ', E.Message);
  end;

  WriteLn;
  {$IFDEF MSWINDOWS}
  WriteLn('Press Enter to exit...');
  ReadLn;
  {$ENDIF}
end.