(Delphi DLL) Google Cloud Storage List Bucket Objects

See more Google Cloud Storage Examples

List the objects in a Google Cloud Storage bucket.

For more information, see https://cloud.google.com/storage/docs/json_api/v1/objects/list

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, Http, StringBuilder, HttpResponse, JsonObject;

...

procedure TForm1.Button1Click(Sender: TObject);
var
sbToken: HCkStringBuilder;
http: HCkHttp;
success: Boolean;
resp: HCkHttpResponse;
responseCode: Integer;
json: HCkJsonObject;
id: PWideChar;
selfLink: PWideChar;
mediaLink: PWideChar;
name: PWideChar;
bucket: PWideChar;
generation: PWideChar;
metageneration: PWideChar;
contentType: PWideChar;
storageClass: PWideChar;
size: PWideChar;
md5Hash: PWideChar;
crc32c: PWideChar;
etag: PWideChar;
timeCreated: PWideChar;
updated: PWideChar;
timeStorageClassUpdated: PWideChar;
kind: PWideChar;
i: Integer;
count_i: Integer;

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

// This example uses a previously obtained access token having permission for the 
// scope "https://www.googleapis.com/auth/cloud-platform"

// In this example, Get Google Cloud Storage OAuth2 Access Token, 
// the service account access token was saved to a text file.  This example fetches the access token from the file..
sbToken := CkStringBuilder_Create();
CkStringBuilder_LoadFile(sbToken,'qa_data/tokens/googleCloudStorageAccessToken.txt','utf-8');

http := CkHttp_Create();
CkHttp_putAuthToken(http,CkStringBuilder__getAsString(sbToken));

// For more info see Cloud Storage Documentation - Objects: list 
// 
success := CkHttp_SetUrlVar(http,'bucket','chilkat-ocean');
success := CkHttp_SetUrlVar(http,'PROJECT_NAME','ChilkatCloud');

resp := CkHttp_QuickGetObj(http,'https://www.googleapis.com/storage/v1/b/{$bucket}/o?project={$ChilkatCloud}');
if (CkHttp_getLastMethodSuccess(http) = False) then
  begin
    Memo1.Lines.Add(CkHttp__lastErrorText(http));
    Exit;
  end;

responseCode := CkHttpResponse_getStatusCode(resp);
if (responseCode = 401) then
  begin
    Memo1.Lines.Add(CkHttpResponse__bodyStr(resp));
    Memo1.Lines.Add('If invalid credentials, then it is likely the access token expired.');
    Memo1.Lines.Add('Your app should automatically fetch a new access token and re-try.');
    CkHttpResponse_Dispose(resp);
    Exit;
  end;

Memo1.Lines.Add('Response code: ' + IntToStr(responseCode));
Memo1.Lines.Add('Response body');

json := CkJsonObject_Create();
success := CkJsonObject_Load(json,CkHttpResponse__bodyStr(resp));
CkHttpResponse_Dispose(resp);

CkJsonObject_putEmitCompact(json,False);

Memo1.Lines.Add(CkJsonObject__emit(json));

// A response code = 200 indicates success, and the response body contains JSON such as this:

// {
//   "kind": "storage#objects",
//   "items": [
//     {
//       "kind": "storage#object",
//       "id": "chilkat-ocean/file with space char.jpg/1555776690752366",
//       "selfLink": "https://www.googleapis.com/storage/v1/b/chilkat-ocean/o/file%20with%20space%20char.jpg",
//       "mediaLink": "https://www.googleapis.com/download/storage/v1/b/chilkat-ocean/o/file%20with%20space%20char.jpg?generation=1555776690752366&alt=media",
//       "name": "file with space char.jpg",
//       "bucket": "chilkat-ocean",
//       "generation": "1555776690752366",
//       "metageneration": "1",
//       "contentType": "image/jpeg",
//       "storageClass": "MULTI_REGIONAL",
//       "size": "6229",
//       "md5Hash": "LpxZ2/JmI2fcl9/dqF2gSA==",
//       "crc32c": "9RjgwQ==",
//       "etag": "CO6WguiH3+ECEAE=",
//       "timeCreated": "2019-04-20T16:11:30.752Z",
//       "updated": "2019-04-20T16:11:30.752Z",
//       "timeStorageClassUpdated": "2019-04-20T16:11:30.752Z"
//     },
//     {
//       "kind": "storage#object",
// 
//       "id": "chilkat-ocean/penguins.jpg/1555775749593296",
//       "selfLink": "https://www.googleapis.com/storage/v1/b/chilkat-ocean/o/penguins.jpg",
//       "mediaLink": "https://www.googleapis.com/download/storage/v1/b/chilkat-ocean/o/penguins.jpg?generation=1555775749593296&alt=media",
//       "name": "penguins.jpg",
//       "bucket": "chilkat-ocean",
//       "generation": "1555775749593296",
//       "metageneration": "1",
//       "contentType": "image/jpeg",
//       "storageClass": "MULTI_REGIONAL",
//       "size": "777835",
//       "md5Hash": "nTd7EM53jEk4s8fixjoimg==",
//       "crc32c": "ixxYVw==",
//       "etag": "CNCxnqeE3+ECEAE=",
//       "timeCreated": "2019-04-20T15:55:49.593Z",
//       "updated": "2019-04-20T15:55:49.593Z",
//       "timeStorageClassUpdated": "2019-04-20T15:55:49.593Z"
//     },
//     {
//       "kind": "storage#object",
//       "id": "chilkat-ocean/starfish.jpg/1628958192639968",
//       "selfLink": "https://www.googleapis.com/storage/v1/b/chilkat-ocean/o/starfish.jpg",
//       "mediaLink": "https://www.googleapis.com/download/storage/v1/b/chilkat-ocean/o/starfish.jpg?generation=1628958192639968&alt=media",
//       "name": "starfish.jpg",
//       "bucket": "chilkat-ocean",
//       "generation": "1628958192639968",
//       "metageneration": "1",
//       "contentType": "image/jpeg",
//       "storageClass": "MULTI_REGIONAL",
//       "size": "6229",
//       "md5Hash": "LpxZ2/JmI2fcl9/dqF2gSA==",
//       "crc32c": "9RjgwQ==",
//       "etag": "COC/tJP2sPICEAE=",
//       "timeCreated": "2021-08-14T16:23:12.660Z",
//       "updated": "2021-08-14T16:23:12.660Z",
//       "timeStorageClassUpdated": "2021-08-14T16:23:12.660Z"
//     }
//   ]
// }

// Use this online tool to generate parsing code from sample JSON: 
// Generate Parsing Code from JSON

kind := CkJsonObject__stringOf(json,'kind');
i := 0;
count_i := CkJsonObject_SizeOfArray(json,'items');
while i < count_i do
  begin
    CkJsonObject_putI(json,i);
    kind := CkJsonObject__stringOf(json,'items[i].kind');
    id := CkJsonObject__stringOf(json,'items[i].id');
    selfLink := CkJsonObject__stringOf(json,'items[i].selfLink');
    mediaLink := CkJsonObject__stringOf(json,'items[i].mediaLink');
    name := CkJsonObject__stringOf(json,'items[i].name');
    bucket := CkJsonObject__stringOf(json,'items[i].bucket');
    generation := CkJsonObject__stringOf(json,'items[i].generation');
    metageneration := CkJsonObject__stringOf(json,'items[i].metageneration');
    contentType := CkJsonObject__stringOf(json,'items[i].contentType');
    storageClass := CkJsonObject__stringOf(json,'items[i].storageClass');
    size := CkJsonObject__stringOf(json,'items[i].size');
    md5Hash := CkJsonObject__stringOf(json,'items[i].md5Hash');
    crc32c := CkJsonObject__stringOf(json,'items[i].crc32c');
    etag := CkJsonObject__stringOf(json,'items[i].etag');
    timeCreated := CkJsonObject__stringOf(json,'items[i].timeCreated');
    updated := CkJsonObject__stringOf(json,'items[i].updated');
    timeStorageClassUpdated := CkJsonObject__stringOf(json,'items[i].timeStorageClassUpdated');
    i := i + 1;
  end;

CkStringBuilder_Dispose(sbToken);
CkHttp_Dispose(http);
CkJsonObject_Dispose(json);

end;