Provide mechanism for paging

[troydai]

A paging mechanism is helpful when a command needs to process large operation results. It should reduce the memory pressure and improve UI responsiveness.

[troydai]

After investigation I found this feature requires SDK improvement: Azure/azure-sdk-for-python#1296

[lmazuel]

@troydai or not :)

azure-cli/src/azure-cli-core/azure/cli/core/commands/__init__.py

Line 539 in 56bfba8

return list(result)

I return an iterator, and you cast it as a list :)

[troydai]

Misread the code. You're right.

[lmazuel]

@troydai no problem! You'll get me next time for sure :p

[squillace]

@troydai, @lmazuel, where are we on this? I need this command to work, as documented.... it appears as if this was just taken on here: #3323. True?

[karungithub]

Add on to this - I could not find if Azure Storage or compute REST API for some of the listing commands (like VM list) supports paging. If anyone knows the options to use in a REST call to get a paged list of elements, that would be really helpful. Thanks.

[lmazuel]

@karungithub The paging mechanism of ARM is described here:
https://github.com/Azure/azure-resource-manager-rpc/blob/master/v1.0/resource-api-reference.md#get-resource

If you don't have "nextLink" in the documentation or in what you get from Azure. or the "top" parameter, this probably means that the service does not support paging for this operation.

[seanknox]

Hey folks, this continues to a major problem for customers/Microsoft employees needing to managing many app registrations. Without a viable CLI alternative, the portal experience exposes users to accidentally deleting the wrong app registrations.

[troydai]

@seanknox thanks for the feedback. The SDK's paging mechanism acts like a linked list, meaning you can only travel through the entities in one direction page by page. There is no random access. Does this mechanism help the customers?

[seanknox]

No, unfortunately. See the discussion here: #1150

[troydai]

Thank you for pointing to this. Depends on the type of resources, we may provide different solutions. However, the difficult part is to make the change intuitive and usable. We may need to work with service team on this.

[yugangw-msft]

Hey folks, this continues to a major problem for customers/Microsoft employees needing to managing many app registrations

I will fix this through filters such --mine to avoid using unconditional list, which is more or less usage error. Even we have the paging, going through thousands of pages won't really help you find the one you are looking for. See details in #1150

I am closing this, as we will have a different way to fix this