felipecrv commented on code in PR #39298:
URL: https://github.com/apache/arrow/pull/39298#discussion_r1432762652
##########
cpp/src/arrow/filesystem/azurefs.h:
##########
@@ -117,6 +118,54 @@ struct ARROW_EXPORT AzureOptions {
MakeDataLakeServiceClient() const;
};
+namespace internal {
+
+enum class HNSSupport {
+ kUnknown = 0,
+ kContainerNotFound = 1,
+ kDisabled = 2,
+ kEnabled = 3,
+};
+
+/// \brief Performs a request to check if the storage account has Hierarchical
+/// Namespace support enabled.
+///
+/// This check requires a DataLakeFileSystemClient for any container of the
+/// storage account. If the container doesn't exist yet, we just forward that
+/// error to the caller (kContainerNotFound) since that's a proper error to
the operation
+/// on that container anyways -- no need to try again with or without the
knowledge of
+/// Hierarchical Namespace support.
+///
+/// Hierarchical Namespace support can't easily be changed after the storage
account is
+/// created and the feature is shared by all containers in the storage account.
+/// This means the result of this check can (and should!) be cached as soon as
+/// it returns a successful result on any container of the storage account (see
+/// AzureFileSystem::Impl).
+///
+/// The check consists of a call to
DataLakeFileSystemClient::GetAccessControlList()
+/// on the root directory of the container. An approach taken by the Hadoop
Azure
+/// project [1]. A more obvious approach would be to call
+/// BlobServiceClient::GetAccountInfo(), but that endpoint requires elevated
+/// permissions [2] that we can't generally rely on.
+///
+/// [1]:
+///
https://github.com/apache/hadoop/blob/7c6af6a5f626d18d68b656d085cc23e4c1f7a1ef/hadoop-tools/hadoop-azure/src/main/java/org/apache/hadoop/fs/azurebfs/AzureBlobFileSystemStore.java#L356.
+/// [2]:
+///
https://learn.microsoft.com/en-us/rest/api/storageservices/get-blob-service-properties?tabs=azure-ad#authorization
+///
+/// IMPORTANT: If the result is kEnabled or kDisabled, it doesn't necessarily
mean that
+/// the container exists.
+///
+/// \param adlfs_client A DataLakeFileSystemClient for a container of the
storage
+/// account.
+/// \return kEnabled/kDisabled/kContainerNotFound (kUnknown is never
+/// returned).
+Result<HNSSupport> CheckIfHierarchicalNamespaceIsEnabled(
Review Comment:
Because this is called from tests. But note that it's in the `internal`
namespace.
I removed `azurefs_internal.h` and moved everything to `azurefs.cc` to
minimize the export of utilities that mention Azure SDK types and this was the
only one left in the `internal` namespace because it's called directly from
unit tests (cc @Tom-Newton).
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: [email protected]
For queries about this service, please contact Infrastructure at:
[email protected]
