[Storage] exists() for BlobClient and BlobContainerClient

sdk/storage/azure_storage_blob/assets.json

@@ -1,6 +1,6 @@
 {
   "AssetsRepo": "Azure/azure-sdk-assets",
   "AssetsRepoPrefixPath": "rust",
-  "Tag": "rust/azure_storage_blob_f9b39b45b4",
+  "Tag": "rust/azure_storage_blob_fc6c153d44",
   "TagPrefix": "rust/azure_storage_blob"
 }

sdk/storage/azure_storage_blob/src/clients/blob_client.rs

@@ -24,9 +24,10 @@ use crate::{
 };
 use azure_core::{
     credentials::TokenCredential,
+    error::ErrorKind,
     http::{
         policies::{BearerTokenCredentialPolicy, Policy},
-        JsonFormat, NoFormat, RequestContent, Response, Url, XmlFormat,
+        JsonFormat, NoFormat, RequestContent, Response, StatusCode, Url, XmlFormat,
     },
     Bytes, Result,
 };
@@ -355,4 +356,19 @@ impl BlobClient {
     ) -> Result<Response<BlobClientGetAccountInfoResult, NoFormat>> {
         self.client.get_account_info(options).await
     }
+
+    /// Returns `true` if the blob exists, `false` if the blob does not exist, and propagates all other errors.
+    pub async fn exists(&self) -> Result<bool> {
+        match self.client.get_properties(None).await {
+            Ok(_) => Ok(true),
+            Err(e) if e.http_status() == Some(StatusCode::NotFound) => match e.kind() {
+                ErrorKind::HttpResponse {
+                    error_code: Some(error_code),
+                    ..
+                } if error_code == "BlobNotFound" || error_code == "ContainerNotFound" => Ok(false),
+                _ => Ok(false),
+            },
+            Err(e) => Err(e),
+        }
+    }
 }

sdk/storage/azure_storage_blob/src/clients/blob_container_client.rs

@@ -23,9 +23,10 @@ use crate::{
 };
 use azure_core::{
     credentials::TokenCredential,
+    error::ErrorKind,
     http::{
         policies::{BearerTokenCredentialPolicy, Policy},
-        NoFormat, PageIterator, Pager, Response, Url, XmlFormat,
+        NoFormat, PageIterator, Pager, Response, StatusCode, Url, XmlFormat,
     },
     Result,
 };
@@ -275,4 +276,19 @@ impl BlobContainerClient {
     ) -> Result<Response<BlobContainerClientGetAccountInfoResult, NoFormat>> {
         self.client.get_account_info(options).await
     }
+
+    /// Returns `true` if the container exists, `false` if the container does not exist, and propagates all other errors.
+    pub async fn exists(&self) -> Result<bool> {
+        match self.client.get_properties(None).await {
+            Ok(_) => Ok(true),
+            Err(e) if e.http_status() == Some(StatusCode::NotFound) => match e.kind() {
+                ErrorKind::HttpResponse {
+                    error_code: Some(error_code),
+                    ..
+                } if error_code == "ContainerNotFound" => Ok(false),
+                _ => Ok(false),
+            },
+            Err(e) => Err(e),
+        }
+    }
 }

sdk/storage/azure_storage_blob/tests/blob_client.rs

@@ -26,14 +26,16 @@ async fn test_get_blob_properties(ctx: TestContext) -> Result<(), Box<dyn Error>
     let container_client = get_container_client(recording, false).await?;
     let blob_client = container_client.blob_client(get_blob_name(recording));
 
-    // Invalid Container Scenario
+    // Container Doesn't Exist Scenario
     let response = blob_client.get_properties(None).await;
 
     // Assert
     let error = response.unwrap_err().http_status();
     assert_eq!(StatusCode::NotFound, error.unwrap());
+    assert!(!blob_client.exists().await?);
 
     container_client.create_container(None).await?;
+    assert!(!blob_client.exists().await?);
     create_test_blob(&blob_client, None, None).await?;
 
     // No Option Scenario
@@ -49,6 +51,7 @@ async fn test_get_blob_properties(ctx: TestContext) -> Result<(), Box<dyn Error>
     assert_eq!(17, content_length.unwrap());
     assert!(etag.is_some());
     assert!(creation_time.is_some());
+    assert!(blob_client.exists().await?);
 
     container_client.delete_container(None).await?;
     Ok(())

sdk/storage/azure_storage_blob/tests/blob_container_client.rs

@@ -43,6 +43,7 @@ async fn test_get_container_properties(ctx: TestContext) -> Result<(), Box<dyn E
     assert!(response.is_err());
     let error = response.unwrap_err().http_status();
     assert_eq!(StatusCode::NotFound, error.unwrap());
+    assert!(!container_client.exists().await?);
 
     // Container Exists Scenario
     container_client.create_container(None).await?;
@@ -53,6 +54,7 @@ async fn test_get_container_properties(ctx: TestContext) -> Result<(), Box<dyn E
     // Assert
     assert_eq!(LeaseState::Available, lease_state.unwrap());
     assert!(!has_immutability_policy.unwrap());
+    assert!(container_client.exists().await?);
 
     container_client.delete_container(None).await?;
     Ok(())