Google Cloud Storage

This backend provides Django File API for Google Cloud Storage using the Python library provided by Google.

Installation

Use pip to install from PyPI:

pip install django-storages[google]

Authentication

By default, this library will try to use the credentials associated with the current Google Cloud infrastructure/environment for authentication.

In most cases, the default service accounts are not sufficient to read/write and sign files in GCS, so you will need to create a dedicated service account:

  1. Create a service account. (Google Getting Started Guide)
  2. Make sure your service account has access to the bucket and appropriate permissions. (Using IAM Permissions)
  3. Ensure this service account is associated to the type of compute being used (Google Compute Engine (GCE), Google Kubernetes Engine (GKE), Google Cloud Run (GCR), etc)

For development use cases, or other instances outside Google infrastructure:

  1. Create the key and download your-project-XXXXX.json file.
  2. Ensure the key is mounted/available to your running Django app.
  3. Set an environment variable of GOOGLE_APPLICATION_CREDENTIALS to the path of the json file.

Alternatively, you can use the setting GS_CREDENTIALS as described below.

Getting Started

Set the default storage and bucket name in your settings.py file

# django < 4.2
DEFAULT_FILE_STORAGE = 'storages.backends.gcloud.GoogleCloudStorage'

# django >= 4.2
STORAGES = {"default": {"BACKEND": "storages.backends.gcloud.GoogleCloudStorage"}}

GS_BUCKET_NAME = 'YOUR_BUCKET_NAME_GOES_HERE'

To allow django-admin collectstatic to automatically put your static files in your bucket set the following in your settings.py:

# django < 4.2
STATICFILES_STORAGE = 'storages.backends.gcloud.GoogleCloudStorage'

# django >= 4.2
STORAGES = {"staticfiles": {"BACKEND": "storages.backends.gcloud.GoogleCloudStorage"}}

Once you’re done, default_storage will be Google Cloud Storage

>>> from django.core.files.storage import default_storage
>>> print(default_storage.__class__)
<class 'storages.backends.gcloud.GoogleCloudStorage'>

This way, if you define a new FileField, it will use the Google Cloud Storage

>>> from django.db import models
>>> class Resume(models.Model):
...     pdf = models.FileField(upload_to='pdfs')
...     photos = models.ImageField(upload_to='photos')
...
>>> resume = Resume()
>>> print(resume.pdf.storage)
<storages.backends.gcloud.GoogleCloudStorage object at ...>

Settings

GS_BUCKET_NAME

Your Google Storage bucket name, as a string. Required.

GS_PROJECT_ID (optional)

Your Google Cloud project ID. If unset, falls back to the default inferred from the environment.

GS_IS_GZIPPED (optional: default is False)

Whether or not to enable gzipping of content types specified by GZIP_CONTENT_TYPES

GZIP_CONTENT_TYPES (optional: default is text/css, text/javascript, application/javascript, application/x-javascript, image/svg+xml)

When GS_IS_GZIPPED is set to True the content types which will be gzipped

GS_CREDENTIALS (optional)

The OAuth 2 credentials to use for the connection. If unset, falls back to the default inferred from the environment (i.e. GOOGLE_APPLICATION_CREDENTIALS)

from google.oauth2 import service_account

GS_CREDENTIALS = service_account.Credentials.from_service_account_file(
    "path/to/credentials.json"
)

GS_DEFAULT_ACL (optional, default is None)

ACL used when creating a new blob, from the list of predefined ACLs. (A “JSON API” ACL is preferred but an “XML API/gsutil” ACL will be translated.)

For most cases, the blob will need to be set to the publicRead ACL in order for the file to be viewed. If GS_DEFAULT_ACL is not set, the blob will have the default permissions set by the bucket.

publicRead files will return a public, non-expiring url. All other files return a signed (expiring) url.

Note

GS_DEFAULT_ACL must be set to ‘publicRead’ to return a public url. Even if you set the bucket to public or set the file permissions directly in GCS to public.

Note

When using this setting, make sure you have fine-grained access control enabled on your bucket, as opposed to Uniform access control, or else, file uploads will return with HTTP 400. If you already have a bucket with Uniform access control set to public read, please keep GS_DEFAULT_ACL to None and set GS_QUERYSTRING_AUTH to False.

GS_QUERYSTRING_AUTH (optional, default is True)

If set to False it forces the url not to be signed. This setting is useful if you need to have a bucket configured with Uniform access control configured with public read. In that case you should force the flag GS_QUERYSTRING_AUTH = False and GS_DEFAULT_ACL = None

GS_FILE_OVERWRITE (optional: default is True)

By default files with the same name will overwrite each other. Set this to False to have extra characters appended.

GS_MAX_MEMORY_SIZE (optional)

The maximum amount of memory a returned file can take up (in bytes) before being rolled over into a temporary file on disk. Default is 0: Do not roll over.

GS_BLOB_CHUNK_SIZE (optional: default is None)

The size of blob chunks that are sent via resumable upload. If this is not set then the generated request must fit in memory. Recommended if you are going to be uploading large files.

Note

This must be a multiple of 256K (1024 * 256)

GS_OBJECT_PARAMETERS (optional: default is {})

Dictionary of key-value pairs mapping from blob property name to value.

Use this to set parameters on all objects. To set these on a per-object basis, subclass the backend and override GoogleCloudStorage.get_object_parameters.

The valid property names are

acl
cache_control
content_disposition
content_encoding
content_language
content_type
metadata
storage_class

If not set, the content_type property will be guessed.

If set, acl overrides GS_DEFAULT_ACL.

Warning

Do not set name. This is set automatically based on the filename.

GS_CUSTOM_ENDPOINT (optional: default is None)

Sets a custom endpoint, that will be used instead of https://storage.googleapis.com when generating URLs for files.

GS_LOCATION (optional: default is '')

Subdirectory in which the files will be stored. Defaults to the root of the bucket.

GS_EXPIRATION (optional: default is timedelta(seconds=86400))

The time that a generated URL is valid before expiration. The default is 1 day. Public files will return a url that does not expire. Files will be signed by the credentials provided to django-storages (See GS Credentials).

Note: Default Google Compute Engine (GCE) Service accounts are unable to sign urls.

The GS_EXPIRATION value is handled by the underlying Google library. It supports timedelta, datetime, or integer seconds since epoch time.

Note: The maximum value for this option is 7 days (604800 seconds) in version v4 (See this Github issue)

Usage

Fields

Once you’re done, default_storage will be Google Cloud Storage

>>> from django.core.files.storage import default_storage
>>> print(default_storage.__class__)
<class 'storages.backends.gcloud.GoogleCloudStorage'>

This way, if you define a new FileField, it will use the Google Cloud Storage

>>> from django.db import models
>>> class Resume(models.Model):
...     pdf = models.FileField(upload_to='pdfs')
...     photos = models.ImageField(upload_to='photos')
...
>>> resume = Resume()
>>> print(resume.pdf.storage)
<storages.backends.gcloud.GoogleCloudStorage object at ...>

Storage

Standard file access options are available, and work as expected

>>> default_storage.exists('storage_test')
False
>>> file = default_storage.open('storage_test', 'w')
>>> file.write('storage contents')
>>> file.close()

>>> default_storage.exists('storage_test')
True
>>> file = default_storage.open('storage_test', 'r')
>>> file.read()
'storage contents'
>>> file.close()

>>> default_storage.delete('storage_test')
>>> default_storage.exists('storage_test')
False

Model

An object without a file has limited functionality

>>> obj1 = Resume()
>>> obj1.pdf
<FieldFile: None>
>>> obj1.pdf.size
Traceback (most recent call last):
...
ValueError: The 'pdf' attribute has no file associated with it.

Saving a file enables full functionality

>>> obj1.pdf.save('django_test.txt', ContentFile('content'))
>>> obj1.pdf
<FieldFile: tests/django_test.txt>
>>> obj1.pdf.size
7
>>> obj1.pdf.read()
'content'

Files can be read in a little at a time, if necessary

>>> obj1.pdf.open()
>>> obj1.pdf.read(3)
'con'
>>> obj1.pdf.read()
'tent'
>>> '-'.join(obj1.pdf.chunks(chunk_size=2))
'co-nt-en-t'

Save another file with the same name

>>> obj2 = Resume()
>>> obj2.pdf.save('django_test.txt', ContentFile('more content'))
>>> obj2.pdf
<FieldFile: tests/django_test_.txt>
>>> obj2.pdf.size
12

Push the objects into the cache to make sure they pickle properly

>>> cache.set('obj1', obj1)
>>> cache.set('obj2', obj2)
>>> cache.get('obj2').pdf
<FieldFile: tests/django_test_.txt>