Create event in google calendar ClientLogin - Delphi language

Question

Bad formatting aside (which I have to assume is NOT in your actual code), one problem your code has is that you are posting the XML as a TStringList. That will not work, as TIdHTTP will encode the XML in a manner that breaks the XML. You need to post the XML as a TStream instead so TIdHTTP will post it as-is without encoding it.

Try this:

  sXML := '<?xml version="1.0" encoding="UTF-8"?>'#13#10 +
          '<entry xmlns="http://www.w3.org/2005/Atom" xmlns:gd="http://schemas.google.com/g/2005">'#13#10 +
          '<category scheme="http://schemas.google.com/g/2005#kind" term="http://schemas.google.com/g/2005#event"/>'#13#10 +
          '<title type="text">' + title + '</title>'#13#10 +
          '<content type="text">' + content + '</content>'#13#10 +
          '<gd:transparency value="http://schemas.google.com/g/2005#event.opaque"/>'#13#10 +
          '<gd:eventStatus value="http://schemas.google.com/g/2005#event.confirmed"/>'#13#10 +
          '<gd:where valueString="' + location + '"/>'#13#10 +
          '<gd:when startTime="' + EventStartTime + '" endTime="' + eventEndTime + '"/>'#13#10 +
          '</entry>';

  slPost := TStringList.Create;
  try    
    slPost.Values['accountType'] := 'HOSTED_OR_GOOGLE';
    slPost.Values['email'] := email;
    slPost.Values['Passwd'] := pass;
    slPost.Values['service'] := 'cl';
    slPost.Values['source'] := '123';

    idHTTP1.IOHandler := IdSSLIOHandlerSocketOpenSSL1 ;
    idHTTP1.Request.ContentType := 'application/x-www-form-urlencoded';
    Responsetxt := idHTTP1.Post('https://www.google.com/accounts/ClientLogin', slPost);
  finally
    slPost.Free;
  end;

  slReply := TStringList.Create;
  try
    slReply.Delimiter := #10;
    slReply.DelimitedText := Responsetxt;
    FAuthID := slReply.Values['Auth'];
  finally
    slReply.Free;
  end;

  if Length(FAuthID) > 0 then
  begin
    try
      URL := 'https://www.google.com/calendar/feeds/' + NormalizeField(email) + '/private/full';

      try
        // you did not say which version of Delphi or Indy
        // you are using, so I am taking some guesses...
        {$IFDEF UNICODE}
        CreateXML := TStringStream.Create(sXML, TEncoding.UTF8);
        {$ELSE}
        CreateXML : = TMemoryStream.Create;
        WriteStringToStream(CreateXML, sXML, enUTF8);
        CreateXML.Position := 0;
        {$ENDIF}

        try
          idHTTP2.IOHandler := IdSSLIOHandlerSocketOpenSSL1;
          idHTTP2.Request.Connection := 'Keep-Alive';
          idHTTP2.Request.ContentType := 'application/atom+xml';
          idHTTP2.Request.CustomHeaders.Values['GData-Version'] := '2.0';
          idHTTP2.Request.CustomHeaders.Values['Authorization'] := 'GoogleLogin Auth=" + FAuthID;

          Responsetxt := idHTTP2.Post(URL, CreateXML);
        finally
          CreateXML.Free;
        end;
      except
        on E: EIdHTTPProtocolException do
        begin
          ...
        end;
      end;

With that said, you should consider creating your XML using an actual XML library, eg:

uses
  ..., XmlIntf, XmlDoc;

var
  XMLDoc: IXMLDocument;
  Entry: IXMLNode;
  Node: IXMLNode;
begin
  ...

  XMLDoc := NewXMLDocument;

  Entry := XMLDoc.AddChild('entry', 'http://www.w3.org/2005/Atom');
  Entry.DeclareNamespace('gd', 'http://schemas.google.com/g/2005');

  Node := Entry.AddChild('category');
  Node.Attribute['scheme'] := 'http://schemas.google.com/g/2005#kind';
  Node.Attribute['term'] := 'http://schemas.google.com/g/2005#event';

  Node := Entry.AddChild('title');
  Node.Attribute['type'] := 'text';
  Node.Text := title;

  Node := Entry.AddChild('content');
  Node.Attribute['type'] := 'text';
  Node.Text := content;

  Node := Entry.AddChild('gd:transparency');
  Node.Attribute['value'] := 'http://schemas.google.com/g/2005#event.opaque';

  Node := Entry.AddChild('gd:eventStatus');
  Node.Attribute['value'] := 'http://schemas.google.com/g/2005#event.confirmed';

  Node := Entry.AddChild('gd:where');
  Node.Attribute['valueString'] := location;

  Node := Entry.AddChild('gd:when');
  Node.Attribute['startTime'] := EventStartTime;
  Node.Attribute['endTime'] := eventEndTime;

  CreateXML := TMemoryStream.Create;
  try
    XMLDoc.SaveToStream(CreateXML);
    CreateXML.Position := 0;
    ...
    Responsetxt := idHTTP2.Post(URL, CreateXML);
  finally
    CreateXML.Free;
  end;

  ...
end;