Delphi DLL GMail: Parse GMail REST API Error Response

Back to Index

Gets the current user's Gmail profile, but shows an error response and how to parse it..

Documentation: https://developers.google.com/gmail/api/v1/reference/users/getProfile

var
rest: HCkRest;
success: Boolean;
oauth2: HCkOAuth2;
sbJson: HCkStringBuilder;
json: HCkJsonObject;
errorCode: Integer;
errorMessage: PWideChar;
i: Integer;
count_i: Integer;
domain: PWideChar;
reason: PWideChar;
message: PWideChar;
extendedHelp: PWideChar;

begin
rest := CkRest_Create();

//   Provide a previously obtained OAuth2 access token.
oauth2 := CkOAuth2_Create();
CkOAuth2_putAccessToken(oauth2,'OAUTH2_ACCESS_TOKEN');
CkRest_SetAuthOAuth2(rest,oauth2);

success := CkRest_Connect(rest,'www.googleapis.com',443,True,True);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkRest__lastErrorText(rest));
    Exit;
  end;

CkRest_AddPathParam(rest,'userId','matt@chilkat.io');

sbJson := CkStringBuilder_Create();
success := CkRest_FullRequestNoBodySb(rest,'GET','/gmail/v1/users/userId/profile',sbJson);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkRest__lastErrorText(rest));
    Exit;
  end;

if (CkRest_getResponseStatusCode(rest) <> 200) then
  begin
    Memo1.Lines.Add('Received error response code: ' + IntToStr(CkRest_getResponseStatusCode(rest)));
    Memo1.Lines.Add('Response body:');
    Memo1.Lines.Add(CkStringBuilder__getAsString(sbJson));
    Exit;
  end;

json := CkJsonObject_Create();
CkJsonObject_LoadSb(json,sbJson);

//  The following code parses the JSON response.
//  A sample JSON response is shown below the sample code.

errorCode := CkJsonObject_IntOf(json,'error.code');
errorMessage := CkJsonObject__stringOf(json,'error.message');
i := 0;
count_i := CkJsonObject_SizeOfArray(json,'error.errors');
while i < count_i do
  begin
CkJsonObject_putI(json,i);
    domain := CkJsonObject__stringOf(json,'error.errors[i].domain');
    reason := CkJsonObject__stringOf(json,'error.errors[i].reason');
    message := CkJsonObject__stringOf(json,'error.errors[i].message');
    extendedHelp := CkJsonObject__stringOf(json,'error.errors[i].extendedHelp');
    i := i + 1;
  end;

Memo1.Lines.Add('Example Completed.');

CkRest_Dispose(rest);
CkOAuth2_Dispose(oauth2);
CkStringBuilder_Dispose(sbJson);
CkJsonObject_Dispose(json);

Sample JSON Response Body

{
 "error": {
  "errors": [
   {
    "domain": "usageLimits",
    "reason": "accessNotConfigured",
    "message": "Access Not Configured. Gmail API has not been used in project 377697329735 before or it is disabled. Enable it by visiting https://console.developers.google.com/apis/api/gmail.googleapis.com/overview?project=377697329735 then retry. If you enabled this API recently, wait a few minutes for the action to propagate to our systems and retry.",
    "extendedHelp": "https://console.developers.google.com/apis/api/gmail.googleapis.com/overview?project=377697329735"
   }
  ],
  "code": 403,
  "message": "Access Not Configured. Gmail API has not been used in project 377697329735 before or it is disabled. Enable it by visiting https://console.developers.google.com/apis/api/gmail.googleapis.com/overview?project=377697329735 then retry. If you enabled this API recently, wait a few minutes for the action to propagate to our systems and retry."
 }
}