llamazure.azrest 0.3.0

Azure REST client

llamazure.azrest : A REST client for the Azure API

Usage

llamazure.azrest has 3 primary components:

1. an Engine for running requests
2. an OpenAPI Generator for creating bindings for Azure services
3. the Bindings created by the Generator and submitted to the Engine

The general workflow is:

1. use the Generator to codegen Bindings
2. create an Engine
3. use the Bindings to create requests
4. run those requests with the Engine

You only need to run regenrate the bindings to upgrade the version of llamazure or to change the version of the Azure API you're targeting. If you're using the shell, you can use:

python3 llamazure-azrest-openapi 'https://raw.githubusercontent.com/Azure/azure-rest-api-specs/main/' 'specification/authorization/resource-manager/Microsoft.Authorization/stable/2022-04-01/authorization-RoleAssignmentsCalls.json' 'my/module/role_asn.py' 

If you're using the Pants build system, try something like:

adhoc_tool(
	name="role_asn",
	runnable="//llamazure/azrest/openapi.py",  # TODO: adapt for out-of-tree
	args=[
		"https://raw.githubusercontent.com/Azure/azure-rest-api-specs/main/",
		"specification/authorization/resource-manager/Microsoft.Authorization/stable/2022-04-01/authorization-RoleAssignmentsCalls.json",
		"my/module/az",
	],
	output_directories=["my/module/az"],
	root_output_directory=".",
)

experimental_wrap_as_python_sources(
	name="azgen",
	inputs=[
		":role_asn",
        ...
	],
)

And then in your code:

from azure.identity import DefaultAzureCredential
from llamazure.azrest.azrest import AzRest

from my.module.role_asn import AzRoleAssignments
# create the Engine
az = AzRest.from_credential(DefaultAzureCredential())

# use the Bindings to create the request
req = AzRoleAssignments.ListForScope(scope="/")

# run the request
role_assignments = az.call(req)

Some Azure datatypes are subsets of others. For example, a FooResource might also have FooResourceUpdateParams, which is mostly the same. You can use the cast_as function for this:

from llamazure.azrest.models import cast_as

d = Dashboard(...)
cast_as(d, PatchableDashboard)

Using the secret batching API

Azure lets you batch several requests into one request. This can save you round-trip time.

from azure.identity import DefaultAzureCredential
from llamazure.azrest.azrest import AzRest
from llamazure.azrest.models import BatchReq

from my.module.role_asn import AzRoleAssignments

az = AzRest.from_credential(DefaultAzureCredential())
query_subscriptions: list[str] = [...]

# use the bindings to create multiple requests
reqs = [AzRoleAssignments.ListForSubscription(sub) for sub in query_subscriptions]
# gather those into a batch
# the `BatchReq.gather` method automatically assigns them IDs
batch_req = BatchReq.gather(reqs)
# you can also name them explicitly
named_reqs = {sub: AzRoleAssignments.ListForSubscription(sub) for sub in query_subscriptions}
batch_req = BatchReq(named_reqs)

az.call_batch(batch_req)

Services with other domain

Some services need different hosts. For example, keyvaults use https://myvault.vault.azure.net. Using these services requires creating a separate AzRest instance to execute those requests:

from azure.identity import DefaultAzureCredential
from llamazure.azrest.azrest import AzRest

a = AzRest.from_credential(DefaultAzureCredential(), token_scope="https://vault.azure.net/.default", base_url="https://myvault.vault.azure.net")

Manually constructing requests

You can build requests yourself

from llamazure.azrest.models import Req

req = Req.get(
    name="List my spacecraft",  # this is a meaningful name for you. It will appear in logs
    path="/subscriptions/00000000-0000-0000-0000-000000000000/resourceGroups/spaaaaaaaace/providers/Microsoft.Orbital/spacecrafts/potato",
    apiv="2022-11-01",
    ret_t=dict, # This is the return type you expect. You can use a Pydantic BaseModel. A Pydantic TypeAdapter is used to deserialise the return. 
)

For requests that expect a body, use a Pydantic BaseModel.

You can also modify existing requests. There are even some builtin helpers:

from my.module.role_asn import AzRoleAssignments

secure_rg = "secure-rg"

my_req = AzRoleAssignments.ListForResourceGroup(my_subscription, secure_rg).named("list role assignments on secure rg")

TODO

1. Odata parameters (x-ms-odata) (I'd have to think through the common elements with llamazure.msgraph)
2. Better retries of Batch elements
3. Enums (x-ms-enum)
4. Nullable (x-nullable)
5. Support path-level parameters

Known Issues

• Pagination doesn't work if the nextLinkName is not "nextLink"

X-MS Support

support	extension	comments
no	x-ms-skip-url-encoding	priority:low really, supporting url encoding is the priority
no	x-ms-enum	priority:hig
no	x-ms-parameter-grouping	priority:low
no	x-ms-parameter-location	priority:low
yes	x-ms-paths
no	x-ms-client-name	priority:med will cause breaking changes in object names
no	x-ms-external	priority:low
no	x-ms-discriminator-value	priority:low The resources that require this are not priorities for me
never	x-ms-client-flatten	In all my experience with the API, this makes it harder to use in any context
mostly	x-ms-parameterized-host	supported, requires a separate AzRest instance
no	x-ms-mutability	priority:low
never	x-ms-examples	No need for examples in code
yes	x-ms-error-response	General error support
no	x-ms-text	priority:low (only in file and blob operations)
no	x-ms-client-default	priority:low You can do this with filters
mostly	x-ms-pageable
no	x-ms-long-running-operation	priority:mid
no	x-ms-long-running-operation-options	priority:mid
no	x-nullable	priority:hig
never	x-ms-header-collection-prefix	I think this isn't for me
never	x-ms-internal	Rude (although it's not used... in the public api)
no	x-ms-odata	priority:hig actually useful
never	x-ms-azure-resource	I'm not generating Terraform providers... yet
no	x-ms-request-id	priority:low I think this might be necessary for some long operations
no	x-ms-client-request-id	priority:low I think this might be necessary for some long operations
no	x-ms-arm-id-details	priority:mid Might be nice to accept/convert the real resource
no	x-ms-secret	priority:low seems more design-by-contract
no	x-ms-identifiers	priority:low
never	x-ms-azure-rbac-permissions-required	Not for me