Access public data

API Link

1. Get the name of the public object and the bucket that stores the object.

2. Use the following URI to access an object in the bucket:

   https://storage.googleapis.com/BUCKET_NAME/OBJECT_NAME

For example, the Google public bucket gcp-public-data-landsat contains the Landsat public dataset. You can link to the publicly shared object LC08/01/001/003/LC08_L1GT_001003_20140812_20170420_01_T2/LC08_L1GT_001003_20140812_20170420_01_T2_B3.TIF with the link:

https://storage.googleapis.com/gcp-public-data-landsat/LC08/01/001/003/LC08_L1GT_001003_20140812_20170420_01_T2/LC08_L1GT_001003_20140812_20170420_01_T2_B3.TIF

Console

1. Get the name of the public object and the bucket that stores the object.

2. Using a web browser, access the object with the following URI (you are asked to sign in if you are not already signed in):

   https://console.cloud.google.com/storage/browser/_details/BUCKET_NAME/OBJECT_NAME

3. If the public has permission to list the bucket's contents, you can list all the objects in the bucket with the following URI:

   https://console.cloud.google.com/storage/browser/BUCKET_NAME

For example, the Google public bucket gcp-public-data-landsat contains the Landsat public dataset. You can access the bucket with:

https://console.cloud.google.com/storage/browser/gcp-public-data-landsat

Command line

1. If you don't have the gcloud CLI, follow these instructions to install it.

   • When installing the gcloud CLI, if you don't want to authenticate, skip the step of running the command gcloud init, and instead run the following command:

     gcloud config set auth/disable_credentials True

2. Get the name of the public object and the bucket that stores the object.

3. If permission to list the bucket's contents is granted to the public, you can list some or all of the objects contained in the bucket by using the ls command.

   For example, the Google public bucket gcp-public-data-landsat contains the Landsat public dataset. You can list objects with the prefix LC08/01/001/003/LC with the following command:

   gcloud storage ls --recursive gs://gcp-public-data-landsat/LC08/01/001/003/LC*

4. Download specific public objects contained in the bucket by using the cp command.

   For example, the following command downloads a file from the bucket gcp-public-data-landsat to your local directory:

   gcloud storage cp gs://gcp-public-data-landsat/LC08/01/001/003/LC08_L1GT_001003_20140812_20170420_01_T2/LC08_L1GT_001003_20140812_20170420_01_T2_B3.TIF .

Client libraries

namespace gcs = ::google::cloud::storage;
[](std::string const& bucket_name, std::string const& object_name) {
  // Create a client that does not authenticate with the server.
  auto client = gcs::Client{
      google::cloud::Options{}.set<google::cloud::UnifiedCredentialsOption>(
          google::cloud::MakeInsecureCredentials())};

  // Read an object, the object must have been made public.
  gcs::ObjectReadStream stream = client.ReadObject(bucket_name, object_name);

  int count = 0;
  std::string line;
  while (std::getline(stream, line, '\n')) {
    ++count;
  }
  if (stream.bad()) throw google::cloud::Status(stream.status());
  std::cout << "The object has " << count << " lines\n";
}

using Google.Cloud.Storage.V1;
using System;
using System.IO;

public class DownloadPublicFileSample
{
    public string DownloadPublicFile(
        string bucketName = "your-bucket-name",
        string objectName = "your-object-name",
        string localPath = "path/to/download/object/to")
    {
        var storage = StorageClient.CreateUnauthenticated();

        using var outputFile = File.OpenWrite(localPath);
        storage.DownloadObject(bucketName, objectName, outputFile);

        Console.WriteLine($"Downloaded public file {objectName} from bucket {bucketName} to {localPath}.");
        return localPath;
    }
}

import (
	"context"
	"fmt"
	"io"
	"time"

	"cloud.google.com/go/storage"
	"google.golang.org/api/option"
)

// downloadPublicFile downloads a public object.
func downloadPublicFile(w io.Writer, bucket, object string) ([]byte, error) {
	// bucket := "bucket-name"
	// object := "object-name"
	ctx := context.Background()
	// Create a client that does not authenticate with the server.
	client, err := storage.NewClient(ctx, option.WithoutAuthentication())
	if err != nil {
		return nil, fmt.Errorf("storage.NewClient: %w", err)
	}
	defer client.Close()

	ctx, cancel := context.WithTimeout(ctx, time.Second*50)
	defer cancel()

	rc, err := client.Bucket(bucket).Object(object).NewReader(ctx)
	if err != nil {
		return nil, fmt.Errorf("Object(%q).NewReader: %w", object, err)
	}
	defer