sqlalchemy_media GoogleCloudStore

google_cloud_store.py

from os import path
from io import BytesIO
from sqlalchemy_media import Store
from sqlalchemy_media.typing_ import FileLike
from sqlalchemy_media.constants import KB
from google.cloud import storage


class GoogleCloudStore(Store):
    """ Store for dealing with Google Cloud Storage """

    BASE_URL_FORMAT = 'https://{0}.storage.googleapis.com'
    DEFAULT_MAX_AGE = 60 * 60 * 24 * 365

    # The chunk size must be a multiple of 256 KB,
    # see https://google-cloud-python.readthedocs.io/en/latest/storage-blobs.html#google.cloud.storage.blob.Blob
    BLOB_CHUNK_SIZE = 256 * KB

    def __init__(self, project, bucket):
        self.project = project
        self.bucket_name = bucket
        self.base_url = self.BASE_URL_FORMAT.format(bucket)

        self._client = None
        self._bucket = None

    @property
    def client(self):
        """ Returns a Google Cloud Storage client for the configured project """

        if not self._client:
            self._client = storage.Client(project=self.project)

        return self._client

    @property
    def bucket(self):
        """ Returns a Google Cloud Storage bucket from the configured client """

        if not self._bucket:
            self._bucket = self.client.get_bucket(self.bucket_name)

        return self._bucket

    def put(self, filename: str, stream: FileLike):
        data = stream.read()
        content_type = stream.content_type

        print(content_type)

        blob = self.bucket.blob(filename, chunk_size=self.BLOB_CHUNK_SIZE)
        blob.upload_from_string(data, content_type=content_type)

        return len(data)

    def delete(self, filename: str):
        blob = self.bucket.blob(filename)
        blob.delete()

    def open(self, filename: str, mode: str=''):
        blob = self.bucket.blob(filename)
        conent = blob.download_as_string()

        print(content)

        return BytesIO(res.content)

    def locate(self, attachment) -> str:
        return path.join(self.base_url, attachment.path)