(Delphi DLL) Google Contacts - Retrieve as JSON

Demonstrates how to retrieve Google Contacts as JSON.

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, StringBuilder, AuthGoogle, JsonObject, Rest;

...

procedure TForm1.Button1Click(Sender: TObject);
var
jsonToken: HCkJsonObject;
success: Boolean;
gAuth: HCkAuthGoogle;
rest: HCkRest;
bAutoReconnect: Boolean;
sbResponseBody: HCkStringBuilder;
json: HCkJsonObject;
totalResults: Integer;
startIndex: Integer;
itemsPerPage: Integer;
numEntries: Integer;
i: Integer;
fullName: PWideChar;
numEmailAddresses: Integer;
j: Integer;
emailAddress: PWideChar;

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

// --------------------------------------------------------------------------------------------------------
// Note: The code for setting up the Chilkat REST object and making the initial connection can be done once.
// Once connected, the REST object may be re-used for many REST API calls.
// (It's a good idea to put the connection setup code in a separate function/subroutine.)
// --------------------------------------------------------------------------------------------------------

// It is assumed we previously obtained an OAuth2 access token.
// This example loads the JSON access token file 
// saved by this example: Get Google Contacts OAuth2 Access Token

jsonToken := CkJsonObject_Create();
success := CkJsonObject_LoadFile(jsonToken,'qa_data/tokens/googleContacts.json');
if (success <> True) then
  begin
    Memo1.Lines.Add('Failed to load googleContacts.json');
    Exit;
  end;

gAuth := CkAuthGoogle_Create();
CkAuthGoogle_putAccessToken(gAuth,CkJsonObject__stringOf(jsonToken,'access_token'));

rest := CkRest_Create();

// Connect using TLS.
bAutoReconnect := True;
success := CkRest_Connect(rest,'www.google.com',443,True,bAutoReconnect);

// Provide the authentication credentials (i.e. the access token)
CkRest_SetAuthGoogle(rest,gAuth);

// ----------------------------------------------
// OK, the REST connection setup is completed..
// ----------------------------------------------

// To retrieve the contacts, we need to send the following:

// 	GET /m8/feeds/contacts/default/full
// 	GData-Version: 3.0

// To get the contacts data in JSON format, set the "alt" query parameter to "json"
CkRest_AddQueryParam(rest,'alt','json');
CkRest_AddHeader(rest,'GData-Version','3.0');

sbResponseBody := CkStringBuilder_Create();
success := CkRest_FullRequestNoBodySb(rest,'GET','/m8/feeds/contacts/default/full',sbResponseBody);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkRest__lastErrorText(rest));
    Exit;
  end;

// A successful response will have a status code equal to 200.
if (CkRest_getResponseStatusCode(rest) <> 200) then
  begin
    Memo1.Lines.Add('response status code = ' + IntToStr(CkRest_getResponseStatusCode(rest)));
    Memo1.Lines.Add('response status text = ' + CkRest__responseStatusText(rest));
    Memo1.Lines.Add('response header: ' + CkRest__responseHeader(rest));
    Memo1.Lines.Add('response body: ' + CkStringBuilder__getAsString(sbResponseBody));
    Exit;
  end;

// If the 200 response was received, then the contacts JSON is contained
// in the response body.
json := CkJsonObject_Create();
CkJsonObject_LoadSb(json,sbResponseBody);
CkJsonObject_putEmitCompact(json,False);

// Save the pretty-printed JSON response to a file.
CkStringBuilder_Clear(sbResponseBody);
CkJsonObject_EmitSb(json,sbResponseBody);
CkStringBuilder_WriteFile(sbResponseBody,'qa_output/google_contacts.json','utf-8',False);

// Parse the Google Contacts JSON, and iterate over the contacts..
totalResults := CkJsonObject_IntOf(json,'feed.openSearch$totalResults.$t');
startIndex := CkJsonObject_IntOf(json,'feed.openSearch$startIndex.$t');
itemsPerPage := CkJsonObject_IntOf(json,'feed.openSearch$itemsPerPage.$t');
Memo1.Lines.Add('totalResults = ' + IntToStr(totalResults));
Memo1.Lines.Add('startIndex = ' + IntToStr(startIndex));
Memo1.Lines.Add('itemsPerPage = ' + IntToStr(itemsPerPage));

numEntries := CkJsonObject_SizeOfArray(json,'feed.entry');
i := 0;
while i < numEntries do
  begin
    CkJsonObject_putI(json,i);
    Memo1.Lines.Add(IntToStr(i + 1) + ' ----');
    Memo1.Lines.Add('title: ' + CkJsonObject__stringOf(json,'feed.entry[i].title.$t'));

    fullName := CkJsonObject__stringOf(json,'feed.entry[i].gd$name.gd$fullName.$t');
    if (CkJsonObject_getLastMethodSuccess(json) = True) then
      begin
        Memo1.Lines.Add('fullName: ' + fullName);
      end;

    // There can be multiple email addresses, so it's stored as a JSON array..
    numEmailAddresses := CkJsonObject_SizeOfArray(json,'feed.entry[i].gd$email');
    j := 0;
    while j < numEmailAddresses do
      begin
        emailAddress := CkJsonObject__stringOf(json,'feed.entry[i].gd$email[j].address');
        if (CkJsonObject_getLastMethodSuccess(json) = True) then
          begin
            Memo1.Lines.Add('email address: ' + emailAddress);
          end;
        j := j + 1;
      end;

    i := i + 1;
  end;

// A sample Google Contacts JSON response:

// 	{ 
// 	  "version": "1.0",
// 	  "encoding": "UTF-8",
// 	  "feed": { 
// 	    "xmlns": "http://www.w3.org/2005/Atom",
// 	    "xmlns$openSearch": "http://a9.com/-/spec/opensearch/1.1/",
// 	    "xmlns$gContact": "http://schemas.google.com/contact/2008",
// 	    "xmlns$batch": "http://schemas.google.com/gdata/batch",
// 	    "xmlns$gd": "http://schemas.google.com/g/2005",
// 	    "gd$etag": "\"QHw5eTVSLyt7I2A9XRFaE0kNTwI.\"",
// 	    "id": { 
// 	      "$t": "chilkat.support@gmail.com"
// 	    },
// 	    "updated": { 
// 	      "$t": "2016-11-17T01:57:41.221Z"
// 	    },
// 	    "category": [
// 	      { 
// 	        "scheme": "http://schemas.google.com/g/2005#kind",
// 	        "term": "http://schemas.google.com/contact/2008#contact"
// 	      }
// 	    ],
// 	    "title": { 
// 	      "$t": "Chilkat Support's Contacts"
// 	    },
// 	    "link": [
// 	      { 
// 	        "rel": "alternate",
// 	        "type": "text/html",
// 	        "href": "https://www.googleapis.com/"
// 	      },
// 	      { 
// 	        "rel": "http://schemas.google.com/g/2005#feed",
// 	        "type": "application/atom+xml",
// 	        "href": "https://www.googleapis.com/m8/feeds/contacts/chilkat.support%40gmail.com/full"
// 	      },
// 	      { 
// 	        "rel": "http://schemas.google.com/g/2005#post",
// 	        "type": "application/atom+xml",
// 	        "href": "https://www.googleapis.com/m8/feeds/contacts/chilkat.support%40gmail.com/full"
// 	      },
// 	      { 
// 	        "rel": "http://schemas.google.com/g/2005#batch",
// 	        "type": "application/atom+xml",
// 	        "href": "https://www.googleapis.com/m8/feeds/contacts/chilkat.support%40gmail.com/full/batch"
// 	      },
// 	      { 
// 	        "rel": "self",
// 	        "type": "application/atom+xml",
// 	        "href": "https://www.googleapis.com/m8/feeds/contacts/chilkat.support%40gmail.com/full?max-results=25&alt=json"
// 	      },
// 	      { 
// 	        "rel": "next",
// 	        "type": "application/atom+xml",
// 	        "href": "https://www.googleapis.com/m8/feeds/contacts/chilkat.support%40gmail.com/full?max-results=25&alt=json&start-index=26"
// 	      }
// 	    ],
// 	    "author": [
// 	      { 
// 	        "name": { 
// 	          "$t": "Chilkat Support"
// 	        },
// 	        "email": { 
// 	          "$t": "chilkat.support@gmail.com"
// 	        }
// 	      }
// 	    ],
// 	    "generator": { 
// 	      "version": "1.0",
// 	      "uri": "http://www.google.com/m8/feeds",
// 	      "$t": "Contacts"
// 	    },
// 	    "openSearch$totalResults": { 
// 	      "$t": "350"
// 	    },
// 	    "openSearch$startIndex": { 
// 	      "$t": "1"
// 	    },
// 	    "openSearch$itemsPerPage": { 
// 	      "$t": "25"
// 	    },
// 	    "entry": [
// 	      { 
// 	        "id": { 
// 	          "$t": "http://www.google.com/m8/feeds/contacts/chilkat.support%40gmail.com/base/0"
// 	        },
// 	        "gd$etag": "\"SX8zcTVSLyt7I2A9WxBXFU4MQwI.\"",
// 	        "updated": { 
// 	          "$t": "2010-01-26T20:07:48.189Z"
// 	        },
// 	        "app$edited": { 
// 	          "xmlns$app": "http://www.w3.org/2007/app",
// 	          "$t": "2010-01-26T20:07:48.189Z"
// 	        },
// 	        "category": [
// 	          { 
// 	            "scheme": "http://schemas.google.com/g/2005#kind",
// 	            "term": "http://schemas.google.com/contact/2008#contact"
// 	          }
// 	        ],
// 	        "title": { 
// 	          "$t": "Joe Sample"
// 	        },
// 	        "link": [
// 	          { 
// 	            "rel": "http://schemas.google.com/contacts/2008/rel#photo",
// 	            "type": "image/*",
// 	            "href": "https://www.googleapis.com/m8/feeds/photos/media/chilkat.support%40gmail.com/0"
// 	          },
// 	          { 
// 	            "rel": "self",
// 	            "type": "application/atom+xml",
// 	            "href": "https://www.googleapis.com/m8/feeds/contacts/chilkat.support%40gmail.com/full/0"
// 	          },
// 	          { 
// 	            "rel": "edit",
// 	            "type": "application/atom+xml",
// 	            "href": "https://www.googleapis.com/m8/feeds/contacts/chilkat.support%40gmail.com/full/0"
// 	          }
// 	        ],
// 	        "gd$name": { 
// 	          "gd$fullName": { 
// 	            "$t": "Joe Sample"
// 	          },
// 	          "gd$givenName": { 
// 	            "$t": "Joe"
// 	          },
// 	          "gd$familyName": { 
// 	            "$t": "Sample"
// 	          }
// 	        },
// 	        "gd$email": [
// 	          { 
// 	            "address": "somebody@gmail.com",
// 	            "primary": "true",
// 	            "rel": "http://schemas.google.com/g/2005#other"
// 	          }
// 	        ]
// 	      },
// 		... more entries ...
// 	

CkJsonObject_Dispose(jsonToken);
CkAuthGoogle_Dispose(gAuth);
CkRest_Dispose(rest);
CkStringBuilder_Dispose(sbResponseBody);
CkJsonObject_Dispose(json);

end;