(Delphi DLL) Twitter - Get Follower IDs

Demonstrates how to get a list of follower IDs for a Twitter user. If the number of followers is more than can be returned in a single response, this example will use cursors to page through the followers.

Note: Rate limits will prevent a program from paging through huge lists of followers. In general, a maximum of 16 GET requests (pages) can be retrieved in a short period of time.

Chilkat for Delphi Downloads Chilkat non-ActiveX DLL for Delphi Chilkat ActiveX DLL for Delphi * The examples here use the non-ActiveX DLL.

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, OAuth1, Rest, JsonObject, StringBuilder;

...

procedure TForm1.Button1Click(Sender: TObject);
var
json: HCkJsonObject;
success: Boolean;
rest: HCkRest;
oauth1: HCkOAuth1;
bAutoReconnect: Boolean;
jsonResponse: HCkJsonObject;
sbNextCursor: HCkStringBuilder;
pageNum: Integer;
caseSensitive: Boolean;
bContinue: Boolean;
resp: PWideChar;
numIds: Integer;
i: Integer;

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

// ----------------------------------------------------------------------
// This initial setup, which involves setting the OAuth1 properties and connecting
// to api.twitter.com, is only required once at the beginning.  Once connected, the same
// object instance may be re-used, and if necessary, it will automatically reconnect
// as needed.

// Assume we've previously obtained an access token and saved it to a JSON file..
json := CkJsonObject_Create();
success := CkJsonObject_LoadFile(json,'qa_data/tokens/twitter.json');

rest := CkRest_Create();
oauth1 := CkOAuth1_Create();

CkOAuth1_putConsumerKey(oauth1,'TWITTER_CONSUMER_KEY');
CkOAuth1_putConsumerSecret(oauth1,'TWITTER_CONSUMER_SECRET');
CkOAuth1_putToken(oauth1,CkJsonObject__stringOf(json,'oauth_token'));
CkOAuth1_putTokenSecret(oauth1,CkJsonObject__stringOf(json,'oauth_token_secret'));
CkOAuth1_putSignatureMethod(oauth1,'HMAC-SHA1');
CkOAuth1_GenNonce(oauth1,16);

CkRest_SetAuthOAuth1(rest,oauth1,False);

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

// This ends the initial setup...
// ----------------------------------------------------------------------

// This Twitter user has about 77.5K followers..
CkRest_AddQueryParam(rest,'screen_name','MarcusMiller959');

jsonResponse := CkJsonObject_Create();
CkJsonObject_putEmitCompact(jsonResponse,False);

// Get the 1st page of results using a cursor of "-1".
sbNextCursor := CkStringBuilder_Create();
CkStringBuilder_SetString(sbNextCursor,'-1');

pageNum := 1;
caseSensitive := False;
bContinue := True;
// Get a maximum of 5 pages (of 5000 ids each).
while bContinue = True do
  begin

    if (CkStringBuilder_ContentsEqual(sbNextCursor,'0',caseSensitive) = True) then
      begin
        // This will cause the loop to exit..
        bContinue := False;
      end
    else
      begin
        // Adds or replaces the query param.
        CkRest_AddQueryParam(rest,'cursor',CkStringBuilder__getAsString(sbNextCursor));

        // Get the next page of follower IDs
        resp := CkRest__fullRequestNoBody(rest,'GET','/1.1/followers/ids.json');
        if (CkRest_getLastMethodSuccess(rest) <> True) then
          begin
            Memo1.Lines.Add(CkRest__lastErrorText(rest));
            Exit;
          end;

        CkJsonObject_Load(jsonResponse,resp);

        if (CkRest_getResponseStatusCode(rest) <> 200) then
          begin
            Memo1.Lines.Add(CkJsonObject__emit(jsonResponse));
            Exit;
          end;

        // Show the number of IDs returned in this 
        numIds := CkJsonObject_SizeOfArray(jsonResponse,'ids');
        Memo1.Lines.Add('Page ' + IntToStr(pageNum) + ', Number of Ids: ' + IntToStr(numIds));

        // Show the 1st 10 ids in this page.
        i := 0;
        while i < numIds do
          begin
            CkJsonObject_putI(jsonResponse,i);
            Memo1.Lines.Add('    ' + IntToStr(i) + ': ' + CkJsonObject__stringOf(jsonResponse,'ids[i]'));

            i := i + 1;
            if (i > 10) then
              begin
                // Force the loop to exit.
                i := numIds;
              end;
          end;

        pageNum := pageNum + 1;
        if (pageNum > 5) then
          begin
            bContinue := False;
          end
        else
          begin
            CkStringBuilder_SetString(sbNextCursor,CkJsonObject__stringOf(jsonResponse,'next_cursor_str'));
          end;
      end;
  end;

// A successful JSON response for the 1st page looks like this:

// 	{
// 	  "ids": [
// 	    3140496044,
// 	    793204773751324672,
// 	    789951187781050369,
// 	    763520773587922945,
// 	    ...
// 	    15031286,
// 	    2668251246,
// 	    3751659443
// 	  ],
// 	  "next_cursor": 1531680438812851153,
// 	  "next_cursor_str": "1531680438812851153",
// 	  "previous_cursor": 0,
// 	  "previous_cursor_str": "0"
// 	}

// The output of this program looks like this:

// 	Page 1, Number of Ids: 5000
// 	    0: 931953350
// 	    1: 786708055
// 	    2: 560845700
// 	    3: 3140496044
// 	    4: 793204773751324672
// 	    5: 789951187781050369
// 	    6: 763520773587922945
// 	    7: 793143274059988992
// 	    8: 793139683412762624
// 	    9: 1588222783
// 	    10: 703821370778451968
// 	Page 2, Number of Ids: 5000
// 	    0: 15031286
// 	    1: 2668251246
// 	    2: 3751659443
// 	    3: 3324584493
// 	    4: 2440214809
// 	    5: 1322335441
// 	    6: 4439178393
// 	    7: 4911573711
// 	    8: 720792880080560128
// 	    9: 720805087124267008
// 	    10: 172926330
// 	Page 3, Number of Ids: 5000
// 	    0: 93867176
// 	    1: 2992946183
// 	    2: 2825296077
// 	    3: 3784572861
// 	    4: 2150051321
// 	    5: 2460881603
// 	    6: 4128849341
// 	    7: 2234697931
// 	    8: 2379418164
// 	    9: 3425171542
// 	    10: 325759186
// 	Page 4, Number of Ids: 5000
// 	    0: 22793412
// 	    1: 3347750489
// 	    2: 316923043
// 	    3: 2481719196
// 	    4: 3363591905
// 	    5: 3238116492
// 	    6: 58467130
// 	    7: 3015182362
// 	    8: 2985342719
// 	    9: 3095965720
// 	    10: 17505957
// 	Page 5, Number of Ids: 5000
// 	    0: 2541434684
// 	    1: 140022957
// 	    2: 134845054
// 	    3: 772810508
// 	    4: 16979294
// 	    5: 2320540225
// 	    6: 105439442
// 	    7: 2796744529
// 	    8: 251128801
// 	    9: 350229758
// 	    10: 2683994716
// 

CkJsonObject_Dispose(json);
CkRest_Dispose(rest);
CkOAuth1_Dispose(oauth1);
CkJsonObject_Dispose(jsonResponse);
CkStringBuilder_Dispose(sbNextCursor);

end;