How to list objects in Google Cloud Storage from PHP

Question

I am trying to list objects in a folder within a Google Cloud Storage bucket. I can get a result with 1000 objects easily (or increase the number if I want) using the following code:

$names = [];
$bucket = $client->bucket('mybucketname');
$options = ['prefix' => 'myfoldername', 'fields' =>' items/name,nextPageToken'];
$objects = $bucket->objects($options);
foreach ($objects as $object) {
  $names[] = $object->name();
}

So far so good, but now I want to get the next 1000 objects (or whatever limit I set using maxResults and resultLimit) using the fact that I specified the nextPageToken object. I know that I have to do this by specifying pageToken as an option - it's just that I have no idea how.

I expect my final code will look something like this - what I need is the line of code which retrieves the next page token.

$names = [];
$bucket = $client->bucket('mybucketname');
$options = ['prefix' => 'myfoldername', 'fields' =>' items/name,nextPageToken'];
while(true) {
  $objects = $bucket->objects($options);
  foreach ($objects as $object) {
    $names[] = $object->name();
  }
  $nextPageToken = $objects->getNextPageTokenSomehowOrOther(); // @todo Need help here!!!!!!!
  if (empty($objects) || empty($nextPageToken)){
    break;
  }
  $options['pageToken'] = $nextPageToken;
}

Any ideas?

Answer 1

The nextPageToken is the name of the last object of the first request encoded in Base64.

Here we have an example from the documentation:

{
  "kind": "storage#objects",
  "nextPageToken": "CgtzaGliYS0yLmpwZw==",
  "items": [
    objects Resource
    …
  ]
}

If you decode the value "CgtzaGliYS0yLmpwZw==" this will reveal the value "shiba-2.jpg"

Here we have the definition of PageToken based on API documentation:

The pageToken is an encoded field that marks the name and generation of the last object in the returned list. In a subsequent request using the pageToken, items that come after the pageToken are shown (up to maxResults).

References:

• https://cloud.google.com/storage/docs/json_api/v1/objects/list#parameters
• https://cloud.google.com/storage/docs/paginate-results#rest-paginate-results

See ya