IdHTTP how to send raw body - http

Question

How i can use IdHTTP to send message as PostMan dos below:
My first attempt was as follow:
function TIdFoo.SendIM(const AID, AMessage: string): Boolean;
const
_URL = 'https://URL.com/SendMessage';
var
Params : TStringStream;
Response : string;
LMsg : string;
begin
Result := False;
LMsg := '-----------------------------13932'+
'Content-Type: application/json; charset=utf-8'+
'Content-Description: message'+ sLineBreak+ '{"message":{"Type":1,"body":"'+AMessage+'"},"to":["'+AID+'"]}'+
'-----------------------------13932--;'+sLineBreak;
Params := TStringStream.Create(LMsg, TEncoding.UTF8);
try
IdHTTP.Request.CustomHeaders.AddValue('authorization', 'Bearer ' + FToken);
IdHTTP.Request.CustomHeaders.AddValue('Origin', 'https://www.URL.com');
IdHTTP.Request.UserAgent := 'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/59.0.3071.104 Safari/537.36';
IdHTTP.Request.Accept := '*/*';
IdHTTP.Request.Referer := 'https://www.URL.com/en-us/';
IdHTTP.Request.Host := 'URL.com';
IdHTTP.Request.AcceptEncoding := 'gzip, deflate, br';
IdHTTP.Request.AcceptLanguage := 'Accept-Language';
IdHTTP.Request.ContentType := 'multipart/mixed; boundary="---------------------------13932"';
Params.Position := 0;
try
Response := IdHTTP.Post(_URL, Params);
Result := True;
except
on E: Exception do
Writeln('Error on Send Message request: '#13#10, e.Message);
end;
Writeln(IdHTTP.Request.RawHeaders.Text);
finally
Params.Free;
end;
end;
The second attempt i try it this way
function TIdFoo.SendIM(const AID, AMessage: string): Boolean;
const
_URL = 'https://URL.com/SendMessage';
var
Params : TStringStream;
Response : string;
LMsg : string;
begin
Result := False;
LMsg := '{"message":{"Type":1,"body":"'+AMessage+'"},"to":["'+AID+'"]}';
Params := TStringStream.Create(LMsg, TEncoding.UTF8);
try
IdHTTP.Request.CustomHeaders.AddValue('authorization', 'Bearer ' + FToken);
IdHTTP.Request.CustomHeaders.AddValue('Origin', 'https://www.URL.com');
IdHTTP.Request.CustomHeaders.AddValue('Content-Description', 'message'); // I addedd this as on PostMan Body
IdHTTP.Request.UserAgent := 'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/59.0.3071.104 Safari/537.36';
IdHTTP.Request.Accept := '*/*';
IdHTTP.Request.Referer := 'https://www.URL.com/en-us/';
IdHTTP.Request.Host := 'URL.com';
IdHTTP.Request.AcceptEncoding := 'gzip, deflate, br';
IdHTTP.Request.AcceptLanguage := 'Accept-Language';
IdHTTP.Request.ContentType := 'application/json; charset=utf-8'; // I alos changed this as it shown on PostMan body
Params.Position := 0;
try
Response := IdHTTP.Post(_URL, Params);
Result := True;
except
on E: Exception do
Writeln('Error on Send Message request: '#13#10, e.Message);
end;
Writeln(IdHTTP.Request.RawHeaders.Text);
finally
Params.Free;
end;
end;
Both attempts gives HTTP/1.1 400 Bad Request.
Can any advice my what i', doing wrong?

Answer 1

In your first example, your "raw" MIME data is not formatted correctly:
You are missing a bunch of required line breaks. And don't use the sLineBreak constant, as its value is platform-specific. MIME expects line breaks to use CRLF specifically. Indy has an EOL constant for that value.
You have an erroneous semicolon on the end of the closing boundary line.
You are also not setting the Request.AcceptEncoding property correctly. DO NOT enable encodings manually, unless you are prepared to actually handle them manually in responses (which your code is not). TIdHTTP handles gzip and deflate encodings for you, if you assign a TIdZLibCompressorBase-derived component, like TIdCompressorZLib, to the TIdHTTP.Compressor property. Don't worry about the br encoding, it is not widely used. In short, leave the Request.AcceptEncoding at its default and let TIdHTTP manage it for you.
You are also not setting the Request.AcceptLanguage property correctly. You should be setting it to 'en-US,en;q=0.8', not to 'Accept-Language'.
Your first example should work if you make these fixes, eg:
function TIdFoo.SendIM(const AID, AMessage: string): Boolean;
const
_URL = 'https://URL.com/SendMessage';
var
Params : TStringStream;
Response : string;
LMsg : string;
begin
Result := False;
LMsg := '-----------------------------13932' + EOL +
'Content-Type: application/json; charset=utf-8' + EOL +
'Content-Description: message' + EOL +
EOL +
'{"message":{"Type":1,"body":"'+AMessage+'"},"to":["'+AID+'"]}' + EOL +
'-----------------------------13932--' + EOL;
Params := TStringStream.Create(LMsg, TEncoding.UTF8);
try
IdHTTP.Request.CustomHeaders.AddValue('Authorization', 'Bearer ' + FToken);
IdHTTP.Request.CustomHeaders.AddValue('Origin', 'https://www.URL.com');
IdHTTP.Request.UserAgent := 'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/59.0.3071.104 Safari/537.36';
IdHTTP.Request.Accept := '*/*';
IdHTTP.Request.Referer := 'https://www.URL.com/en-us/';
IdHTTP.Request.Host := 'URL.com';
IdHTTP.Request.AcceptLanguage := 'en-US,en;q=0.8';
IdHTTP.Request.ContentType := 'multipart/mixed; boundary="---------------------------13932"';
try
Response := IdHTTP.Post(_URL, Params);
Result := True;
except
on E: Exception do
Writeln('Error on Send Message request: '#13#10, e.Message);
end;
Writeln(IdHTTP.Request.RawHeaders.Text);
finally
Params.Free;
end;
end;
Alternatively:
function TIdFoo.SendIM(const AID, AMessage: string): Boolean;
const
_URL = 'https://URL.com/SendMessage';
var
Params : TMemoryStream;
Response : string;
LMsg : string;
begin
Result := False;
Params := TMemoryStream.Create;
try
WriteStringToStream(Params, '-----------------------------13932' + EOL);
WriteStringToStream(Params, 'Content-Type: application/json; charset=utf-8' + EOL);
WriteStringToStream(Params, 'Content-Description: message' + EOL);
WriteStringToStream(Params, EOL);
WriteStringToStream(Params, '{"message":{"Type":1,"body":"'+AMessage+'"},"to":["'+AID+'"]}' + EOL, IndyTextEncoding_UTF8);
WriteStringToStream(Params, '-----------------------------13932--' + EOL);
Params.Position := 0;
IdHTTP.Request.CustomHeaders.AddValue('Authorization', 'Bearer ' + FToken);
IdHTTP.Request.CustomHeaders.AddValue('Origin', 'https://www.URL.com');
IdHTTP.Request.UserAgent := 'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/59.0.3071.104 Safari/537.36';
IdHTTP.Request.Accept := '*/*';
IdHTTP.Request.Referer := 'https://www.URL.com/en-us/';
IdHTTP.Request.Host := 'URL.com';
IdHTTP.Request.AcceptLanguage := 'en-US,en;q=0.8';
IdHTTP.Request.ContentType := 'multipart/mixed; boundary="---------------------------13932"';
try
Response := IdHTTP.Post(_URL, Params);
Result := True;
except
on E: Exception do
Writeln('Error on Send Message request: '#13#10, e.Message);
end;
Writeln(IdHTTP.Request.RawHeaders.Text);
finally
Params.Free;
end;
end;
Alternatively:
function TIdFoo.SendIM(const AID, AMessage: string): Boolean;
const
_URL = 'https://URL.com/SendMessage';
var
Params : TMemoryStream;
Response : string;
LMsg : string;
begin
Result := False;
Params := TMemoryStream.Create;
try
with TStreamWriter.Create(Params, TEncoding.UTF8) do
try
NewLine := EOL;
WriteLine('-----------------------------13932');
WriteLine('Content-Type: application/json; charset=utf-8');
WriteLine('Content-Description: message');
WriteLine;
WriteLine('{"message":{"Type":1,"body":"'+AMessage+'"},"to":["'+AID+'"]}');
WriteLine('-----------------------------13932--');
finally
Free;
end;
Params.Position := 0;
IdHTTP.Request.CustomHeaders.AddValue('Authorization', 'Bearer ' + FToken);
IdHTTP.Request.CustomHeaders.AddValue('Origin', 'https://www.URL.com');
IdHTTP.Request.UserAgent := 'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/59.0.3071.104 Safari/537.36';
IdHTTP.Request.Accept := '*/*';
IdHTTP.Request.Referer := 'https://www.URL.com/en-us/';
IdHTTP.Request.Host := 'URL.com';
IdHTTP.Request.AcceptLanguage := 'en-US,en;q=0.8';
IdHTTP.Request.ContentType := 'multipart/mixed; boundary="---------------------------13932"';
try
Response := IdHTTP.Post(_URL, Params);
Result := True;
except
on E: Exception do
Writeln('Error on Send Message request: '#13#10, e.Message);
end;
Writeln(IdHTTP.Request.RawHeaders.Text);
finally
Params.Free;
end;
end;
In your second example, your "raw" data is just the JSON by itself, not any MIME wrapping it. You are putting MIME headers in the HTTP headers, where they don't belong. This example will not work if the server expects MIME data and not just raw JSON data.
You are also making the same mistakes with the Request.AcceptEncoding and Request.AcceptLanguage properties.
Since you are posting data in MIME format, an easier way to handle this would have been to use Indy's TIdMultipartFormDataStream class instead, and let it handle the MIME formatting for you. However, that class does not currently support:
setting the stream's RequestContentType property to a custom value (in this case, 'multipart/mixed' instead of 'multipart/form-data'). Though, you can use an accessor class to accomplish this, since the FRequestContentType member is protected.
omitting the Content-Disposition: form-data header on individual fields. This might trip up servers that are not expecting form-data submissions.
specifying the Content-Description MIME header at all (see Add support for user-defined MIME headers in TIdMultipartFormDataStream in Indy's issue tracker on GitHub).
So you will have to continue resorting to formatting the MIME data manually. You just have to make sure you get it right.