[Storage] Cache specialized clients (Azure#24615)

* Revert "Increment version for core releases (Azure#24504)"

This reverts commit 8a10ae6

* recording.

* Revert "Revert "Increment version for core releases (Azure#24504)""

This reverts commit ad5155d.

* cache specialized client.

* checkstyle.

* Update BlobAPITest.groovy

Author: kasobol-msft

sdk/storage/azure-storage-blob/src/main/java/com/azure/storage/blob/BlobAsyncClient.java

@@ -101,6 +101,10 @@ public class BlobAsyncClient extends BlobAsyncClientBase {
     static final long BLOB_MAX_UPLOAD_BLOCK_SIZE = 4000L * Constants.MB;
     private final ClientLogger logger = new ClientLogger(BlobAsyncClient.class);
 
+    private BlockBlobAsyncClient blockBlobAsyncClient;
+    private AppendBlobAsyncClient appendBlobAsyncClient;
+    private PageBlobAsyncClient pageBlobAsyncClient;
+
     /**
      * Protected constructor for use by {@link BlobClientBuilder}.
      *
@@ -233,7 +237,10 @@ public BlobAsyncClient getCustomerProvidedKeyAsyncClient(CustomerProvidedKey cus
      * @return A {@link AppendBlobAsyncClient} associated with this blob.
      */
     public AppendBlobAsyncClient getAppendBlobAsyncClient() {
-        return prepareBuilder().buildAppendBlobAsyncClient();
+        if (appendBlobAsyncClient == null) {
+            appendBlobAsyncClient = prepareBuilder().buildAppendBlobAsyncClient();
+        }
+        return appendBlobAsyncClient;
     }
 
     /**
@@ -242,7 +249,10 @@ public AppendBlobAsyncClient getAppendBlobAsyncClient() {
      * @return A {@link BlockBlobAsyncClient} associated with this blob.
      */
     public BlockBlobAsyncClient getBlockBlobAsyncClient() {
-        return prepareBuilder().buildBlockBlobAsyncClient();
+        if (blockBlobAsyncClient == null) {
+            blockBlobAsyncClient = prepareBuilder().buildBlockBlobAsyncClient();
+        }
+        return blockBlobAsyncClient;
     }
 
     /**
@@ -251,7 +261,10 @@ public BlockBlobAsyncClient getBlockBlobAsyncClient() {
      * @return A {@link PageBlobAsyncClient} associated with this blob.
      */
     public PageBlobAsyncClient getPageBlobAsyncClient() {
-        return prepareBuilder().buildPageBlobAsyncClient();
+        if (pageBlobAsyncClient == null) {
+            pageBlobAsyncClient = prepareBuilder().buildPageBlobAsyncClient();
+        }
+        return pageBlobAsyncClient;
     }
 
     private SpecializedBlobClientBuilder prepareBuilder() {

sdk/storage/azure-storage-blob/src/main/java/com/azure/storage/blob/BlobClient.java

@@ -75,6 +75,10 @@ public class BlobClient extends BlobClientBase {
 
     private final BlobAsyncClient client;
 
+    private BlockBlobClient blockBlobClient;
+    private AppendBlobClient appendBlobClient;
+    private PageBlobClient pageBlobClient;
+
     /**
      * Protected constructor for use by {@link BlobClientBuilder}.
      * @param client the async blob client
@@ -136,9 +140,12 @@ public BlobClient getCustomerProvidedKeyClient(CustomerProvidedKey customerProvi
      * @return A {@link AppendBlobClient} associated with this blob.
      */
     public AppendBlobClient getAppendBlobClient() {
-        return new SpecializedBlobClientBuilder()
-            .blobClient(this)
-            .buildAppendBlobClient();
+        if (appendBlobClient == null) {
+            appendBlobClient = new SpecializedBlobClientBuilder()
+                .blobClient(this)
+                .buildAppendBlobClient();
+        }
+        return appendBlobClient;
     }
 
     /**
@@ -147,9 +154,12 @@ public AppendBlobClient getAppendBlobClient() {
      * @return A {@link BlockBlobClient} associated with this blob.
      */
     public BlockBlobClient getBlockBlobClient() {
-        return new SpecializedBlobClientBuilder()
-            .blobClient(this)
-            .buildBlockBlobClient();
+        if (blockBlobClient == null) {
+            blockBlobClient = new SpecializedBlobClientBuilder()
+                .blobClient(this)
+                .buildBlockBlobClient();
+        }
+        return blockBlobClient;
     }
 
     /**
@@ -158,9 +168,12 @@ public BlockBlobClient getBlockBlobClient() {
      * @return A {@link PageBlobClient} associated with this blob.
      */
     public PageBlobClient getPageBlobClient() {
-        return new SpecializedBlobClientBuilder()
-            .blobClient(this)
-            .buildPageBlobClient();
+        if (pageBlobClient == null) {
+            pageBlobClient = new SpecializedBlobClientBuilder()
+                .blobClient(this)
+                .buildPageBlobClient();
+        }
+        return pageBlobClient;
     }
 
     /**

sdk/storage/azure-storage-blob/src/test/java/com/azure/storage/blob/BlobAPITest.groovy

@@ -73,11 +73,13 @@ import java.util.concurrent.atomic.AtomicInteger
 
 class BlobAPITest extends APISpec {
     BlobClient bc
+    BlobAsyncClient bcAsync
     String blobName
 
     def setup() {
         blobName = generateBlobName()
         bc = cc.getBlobClient(blobName)
+        bcAsync = ccAsync.getBlobAsyncClient(blobName)
         bc.getBlockBlobClient().upload(data.defaultInputStream, data.defaultDataSize)
     }
 
@@ -3183,4 +3185,14 @@ class BlobAPITest extends APISpec {
         notThrown(BlobStorageException)
         response.getHeaders().getValue("x-ms-version") == "2017-11-09"
     }
+
+    def "Specialized child client gets cached"() {
+        expect:
+        bc.getBlockBlobClient() == bc.getBlockBlobClient()
+        bc.getAppendBlobClient() == bc.getAppendBlobClient()
+        bc.getPageBlobClient() == bc.getPageBlobClient()
+        bcAsync.getBlockBlobAsyncClient() == bcAsync.getBlockBlobAsyncClient()
+        bcAsync.getAppendBlobAsyncClient() == bcAsync.getAppendBlobAsyncClient()
+        bcAsync.getPageBlobAsyncClient() == bcAsync.getPageBlobAsyncClient()
+    }
 }

sdk/storage/azure-storage-blob/src/test/resources/session-records/BlobAPITestSpecializedChildClientGetsCached.json

@@ -0,0 +1,50 @@
+{
+  "networkCallRecords" : [ {
+    "Method" : "PUT",
+    "Uri" : "https://REDACTED.blob.core.windows.net/c4cb2b070c4cb2b0760d01980b5fbbd116ea5420dbb6?restype=container",
+    "Headers" : {
+      "x-ms-version" : "2020-10-02",
+      "User-Agent" : "azsdk-java-azure-storage-blob/12.15.0-beta.1 (11; Windows 10; 10.0)",
+      "x-ms-client-request-id" : "dfcc68cd-e621-4df0-ad8b-877bbbc6f8bf"
+    },
+    "Response" : {
+      "content-length" : "0",
+      "x-ms-version" : "2020-10-02",
+      "Server" : "Windows-Azure-Blob/1.0 Microsoft-HTTPAPI/2.0",
+      "eTag" : "0x8D989A320D892D6",
+      "Last-Modified" : "Thu, 07 Oct 2021 14:59:57 GMT",
+      "retry-after" : "0",
+      "StatusCode" : "201",
+      "x-ms-request-id" : "eeb0684a-201e-005e-618b-bb2151000000",
+      "x-ms-client-request-id" : "dfcc68cd-e621-4df0-ad8b-877bbbc6f8bf",
+      "Date" : "Thu, 07 Oct 2021 14:59:57 GMT"
+    },
+    "Exception" : null
+  }, {
+    "Method" : "PUT",
+    "Uri" : "https://REDACTED.blob.core.windows.net/c4cb2b070c4cb2b0760d01980b5fbbd116ea5420dbb6/c4cb2b071c4cb2b0760d56405bb0ce39faa19449d9f2",
+    "Headers" : {
+      "x-ms-version" : "2020-10-02",
+      "User-Agent" : "azsdk-java-azure-storage-blob/12.15.0-beta.1 (11; Windows 10; 10.0)",
+      "x-ms-client-request-id" : "577feec8-2ac2-45e2-b191-494f95feddcb",
+      "Content-Type" : "application/octet-stream"
+    },
+    "Response" : {
+      "content-length" : "0",
+      "x-ms-version" : "2020-10-02",
+      "Server" : "Windows-Azure-Blob/1.0 Microsoft-HTTPAPI/2.0",
+      "x-ms-content-crc64" : "6RYQPwaVsyQ=",
+      "Last-Modified" : "Thu, 07 Oct 2021 14:59:57 GMT",
+      "retry-after" : "0",
+      "StatusCode" : "201",
+      "x-ms-request-server-encrypted" : "true",
+      "Date" : "Thu, 07 Oct 2021 14:59:57 GMT",
+      "Content-MD5" : "wh+Wm18D0z1D4E+PE252gg==",
+      "eTag" : "0x8D989A321051AC5",
+      "x-ms-request-id" : "eeb069e3-201e-005e-588b-bb2151000000",
+      "x-ms-client-request-id" : "577feec8-2ac2-45e2-b191-494f95feddcb"
+    },
+    "Exception" : null
+  } ],
+  "variables" : [ "c4cb2b070c4cb2b0760d01980b5fbbd116ea5420dbb6", "c4cb2b071c4cb2b0760d56405bb0ce39faa19449d9f2" ]
+}