Add Azure parameters as kwargs for storage.url

[fao89]

It enables using kwargs, such as content_type, content_disposition, ..., when generating a shared access signature for a blob
https://github.com/Azure/azure-sdk-for-python/blob/main/sdk/storage/azure-storage-blob/azure/storage/blob/_shared_access_signature.py#L482-L574

[ipanova]

@jschneier any chance this can be accepted and released any time soon?Thank you.

[mdellweg]

No need to copy, if it is used read only.

Suggested change

	params = parameters.copy() if parameters else {}
	params = parameters or {}

[fao89]

I tried to follow S3 example:
https://github.com/jschneier/django-storages/blob/master/storages/backends/s3boto3.py#L574-L577

[mdellweg]

Yes, there the dict is augmented before using it. Here it is not.

[jschneier]

How come we only want to run this if expire?

[fao89]

How come we only want to run this if expire?

Good question!
I think so, and renaming parameters to expire_params would make more sense. It would make it easier to document/understand. What do you think?

[ipanova]

How come we only want to run this if expire?

reading trough the docs expire is set to None by default which means it never expires. Any reason why it is not possible create token_sas when expire is not set?

[ipanova]

I see, it boils down to public and private access https://django-storages.readthedocs.io/en/latest/backends/azure.html#private-vs-public-access; tldr in private access there is always an expiration set, and in public access i guess one does not need any credentials.

[jschneier]

I think the name parameters is fine. In the initial message things like content_disposition are mentioned for which public/private isn't a meaningful distinction; that is the source of my questions.

[ipanova]

I think the name parameters is fine. In the initial message things like content_disposition are mentioned for which public/private isn't a meaningful distinction; that is the source of my questions.

Take this with a grain of salt, I am not expert in this area at all, but here is my understanding - expiry is used only with private containers as mentioned in docs, where as a result a SAS token is created and is being used as credentials when calling into from_blob_url

django-storages/storages/backends/azure_storage.py

Line 302 in 493adb7

return BlobClient.from_blob_url(container_blob_url, credential=credential).url

https://docs.microsoft.com/en-us/python/api/azure-storage-blob/azure.storage.blob.blobclient?view=azure-python#examples

https://github.com/Azure/azure-sdk-for-python/blob/main/sdk/storage/azure-storage-blob/azure/storage/blob/_shared_access_signature.py#L558

To hopefully answer your question - apparently there is a limitation and it is not possible to send any headers in a public container since they are passed in the credentials which are used in the SAS token which is used only in private containers.

[jschneier]

That is quite the limitation! Thanks for the info. In that case we should add a disclaimer to the docs, and include the urldocumentation as well.

[fao89]

That is quite the limitation! Thanks for the info. In that case we should add a disclaimer to the docs, and include the urldocumentation as well.

I tried to add some docs, let me know how can I improve it!

Here are the links that I used:

• https://docs.microsoft.com/en-us/rest/api/storageservices/set-blob-properties#remarks
• https://docs.microsoft.com/en-us/python/api/azure-storage-blob/azure.storage.blob?view=azure-python#generate-blob-sas-account-name--container-name--blob-name--snapshot-none--account-key-none--user-delegation-key-none--permission-none--expiry-none--start-none--policy-id-none--ip-none----kwargs-

I didn't added the second one, because it is too big

[ipanova]

can you add These properties include the cache-control, content-type, content-encoding, content-language, and content-disposition properties.

[fao89]

I shared the link of the official docs below, so people could see this note:

but you are right, I'll add the properties here