Added ADLS SDK (#6071)

eng/code-quality-reports/src/main/resources/checkstyle/checkstyle-suppressions.xml

@@ -208,6 +208,8 @@
   <suppress checks="com.azure.tools.checkstyle.checks.ServiceClientCheck" files="com.azure.storage.blob.batch.BlobBatchAsyncClient.java"/>
   <suppress checks="com.azure.tools.checkstyle.checks.ServiceClientCheck" files="com.azure.data.appconfiguration.ConfigurationClient.java"/>
   <suppress checks="com.azure.tools.checkstyle.checks.ServiceClientCheck" files="com.azure.data.appconfiguration.ConfigurationAsyncClient.java"/>
+  <suppress checks="com.azure.tools.checkstyle.checks.ServiceClientCheck" files="com.azure.storage.file.datalake.DataLakeLeaseClient.java"/>
+  <suppress checks="com.azure.tools.checkstyle.checks.ServiceClientCheck" files="com.azure.storage.file.datalake.DataLakeLeaseAsyncClient.java"/>
 
   <!-- Suppress public/private constructor check since BlobClients need protected constructors to create EncryptedClients -->
   <suppress checks="com.azure.tools.checkstyle.checks.ServiceClientCheck" files="com.azure.storage.blob.BlobAsyncClient.java"/>

eng/code-quality-reports/src/main/resources/spotbugs/spotbugs-exclude.xml

@@ -542,7 +542,7 @@
   <!-- It is fine to have un-used variables, unread fields, anonymous static inner classes in javadoc code samples. -->
   <Match>
     <Or>
-      <Class name="~.*JavaDoc(CodeSnippets|CodeSamples)"/>
+      <Class name="~.*JavaDoc(CodeSnippets|CodeSamples|Samples)"/>
       <Class name="com.azure.storage.blob.batch.ReadmeCodeSamples"/>
     </Or>
     <Bug pattern="DLS_DEAD_LOCAL_STORE,

sdk/storage/azure-storage-file-datalake/README.md

@@ -1,20 +1,325 @@
 # Azure File Data Lake client library for Java
 
+Azure Data Lake Storage is Microsoft's optimized storage solution for for big 
+data analytics workloads. A fundamental part of Data Lake Storage Gen2 is the
+addition of a hierarchical namespace to Blob storage. The hierarchical 
+namespace organizes objects/files into a hierarchy of directories for 
+efficient data access.
+
+[Source code][source] | [API reference documentation][docs] | [REST API documentation][rest_docs] | [Product documentation][product_docs] | [Samples][samples]
+
 ## Getting started
 
+### Prerequisites
+
+- [Java Development Kit (JDK)][jdk] with version 8 or above
+- [Azure Subscription][azure_subscription]
+- [Create Storage Account][storage_account]
+
+### Adding the package to your product
+
+Add a dependency on Azure Storage Blob
+[//]: # ({x-version-update-start;com.azure:azure-storage-blob;current})
+```xml
+<dependency>
+    <groupId>com.azure</groupId>
+    <artifactId>azure-storage-blob</artifactId>
+    <version>12.0.0</version>
+</dependency>
+```
+[//]: # ({x-version-update-end})
+
+### Default HTTP Client
+All client libraries, by default, use the Netty HTTP client. Adding the above dependency will automatically configure 
+Storage Data Lake to use the Netty HTTP client. 
+
+### Alternate HTTP client
+If, instead of Netty it is preferable to use OkHTTP, there is an HTTP client available for that too. Exclude the default
+Netty and include the OkHTTP client in your pom.xml.
+
+[//]: # ({x-version-update-start;com.azure:azure-storage-file-datalake;current})
+```xml
+<!-- Add the Storage Data Lake dependency without the Netty HTTP client -->
+<dependency>
+    <groupId>com.azure</groupId>
+    <artifactId>azure-storage-file-datalake</artifactId>
+    <version>12.0.0-preview.5</version>
+    <exclusions>
+        <exclusion>
+            <groupId>com.azure</groupId>
+            <artifactId>azure-core-http-netty</artifactId>
+        </exclusion>
+    </exclusions>
+</dependency>
+```
+[//]: # ({x-version-update-end})
+[//]: # ({x-version-update-start;com.azure:azure-core-http-okhttp;current})
+```xml
+<!-- Add the OkHTTP client to use with Storage Data Lake -->
+<dependency>
+    <groupId>com.azure</groupId>
+    <artifactId>azure-core-http-okhttp</artifactId>
+    <version>1.0.0</version>
+</dependency>
+```
+[//]: # ({x-version-update-end})
+
+### Configuring HTTP Clients
+When an HTTP client is included on the classpath, as shown above, it is not necessary to specify it in the client library [builders](#create-datalakeserviceclient) unless you want to customize the HTTP client in some fashion. If this is desired, the `httpClient` builder method is often available to achieve just this by allowing users to provide custom (or customized) `com.azure.core.http.HttpClient` instances.
+
+For starters, by having the Netty or OkHTTP dependencies on your classpath, as shown above, you can create new instances of these `HttpClient` types using their builder APIs. For example, here is how you would create a Netty HttpClient instance:
+
+```java
+HttpClient client = new NettyAsyncHttpClientBuilder()
+        .port(8080)
+        .wiretap(true)
+        .build();
+```
+
+### Create a Storage Account
+To create a Storage Account you can use the [Azure Portal][storage_account_create_portal] or [Azure CLI][storage_account_create_cli].
+Note: To use data lake, your account must have hierarchical namespace enabled.
+
+```bash
+az storage account create \
+    --resource-group <resource-group-name> \
+    --name <storage-account-name> \
+    --location <location>
+```
+
+### Authenticate the client
+
+In order to interact with the Storage Service you'll need to create an instance of the Service Client class.
+To make this possible you'll need the Account SAS (shared access signature) string of the Storage Account. Learn more at [SAS Token][sas_token]
+
+#### Get credentials
+
+##### SAS Token
+
+a. Use the Azure CLI snippet below to get the SAS token from the Storage Account.
+
+```bash
+az storage blob generate-sas \
+    --account-name {Storage Account name} \
+    --container-name {container name} \
+    --name {blob name} \
+    --permissions {permissions to grant} \
+    --expiry {datetime to expire the SAS token} \
+    --services {storage services the SAS allows} \
+    --resource-types {resource types the SAS allows}
+```
+
+Example:
+
+```bash
+CONNECTION_STRING=<connection-string>
+
+az storage blob generate-sas \
+    --account-name MyStorageAccount \
+    --container-name MyContainer \
+    --name MyBlob \
+    --permissions racdw \
+    --expiry 2020-06-15
+```
+
+b. Alternatively, get the Account SAS Token from the Azure Portal.
+
+1. Go to your Storage Account
+2. Select `Shared access signature` from the menu on the left
+3. Click on `Generate SAS and connection string` (after setup)
+
+##### **Shared Key Credential**
+
+a. Use Account name and Account key. Account name is your Storage Account name.
+
+1. Go to your Storage Account
+2. Select `Access keys` from the menu on the left
+3. Under `key1`/`key2` copy the contents of the `Key` field
+
+or
+
+b. Use the connection string.
+
+1. Go to your Storage Account
+2. Select `Access keys` from the menu on the left
+3. Under `key1`/`key2` copy the contents of the `Connection string` field
+
 ## Key concepts
 
+This preview package for Java includes ADLS Gen2 specific API support made available in Blob SDK. This includes:
+1. New directory level operations (Create, Rename/Move, Delete) for both hierarchical namespace enabled (HNS) storage accounts and HNS disabled storage accounts. For HNS enabled accounts, the rename/move operations are atomic.
+2. Permission related operations (Get/Set ACLs) for hierarchical namespace enabled (HNS) accounts. 
+
+HNS enabled accounts in ADLS Gen2 can also now leverage all of the operations available in Blob SDK. Support for File level semantics for ADLS Gen2 is planned to be made available in Blob SDK in a later release. In the meantime, please find below mapping for ADLS Gen2 terminology to Blob terminology
+
+|ADLS Gen2 	 | Blob       |
+| ---------- | ---------- |
+|Filesystem	 | Container  | 
+|Folder	   	 | Directory  |
+|File		 | Blob       |
+
 ## Examples
 
+The following sections provide several code snippets covering some of the most common Azure Storage Blob tasks, including:
+
+- [Create a `DataLakeServiceClient`](#create-a-datalakeserviceclient)
+- [Create a `DataLakeFileSystemClient`](#create-a-filesystemclient)
+- [Create a `DataLakeFileClient`](#create-a-fileclient)
+- [Create a file system](#create-a-filesystem)
+- [Upload a file from a stream](#upload-a-file-from-a-stream)
+- [Read a file to a stream](#read-a-file-to-a-stream)
+- [Enumerate paths](#enumerate-paths)
+- [Authenticate with Azure Identity](#authenticate-with-azure-identity)
+
+### Create a `DataLakeServiceClient`
+
+Create a `DataLakeServiceClient` using the [`sasToken`](#get-credentials) generated above.
+
+```java
+DataLakeServiceClient dataLakeServiceClient = new DataLakeServiceClientBuilder()
+        .endpoint("<your-storage-dfs-url>")
+        .sasToken("<your-sasToken>")
+        .buildClient();
+```
+
+### Create a `DataLakeFileSystemClient`
+
+Create a `DataLakeFileSystemClient` using a `DataLakeServiceClient`.
+
+```java
+DataLakeFileSystemClient dataLakeFileSystemClient = dataLakeServiceClient.getFileSystemClient("myfilesystem");
+```
+
+or
+
+Create a `DataLakeFileSystemClient` from the builder [`sasToken`](#get-credentials) generated above.
+
+```java
+DataLakeFileSystemClient dataLakeFileSystemClient = new DataLakeFileSystemClientBuilder()
+        .endpoint("<your-storage-dfs-url>")
+        .sasToken("<your-sasToken>")
+        .containerName("myfilesystem")
+        .buildClient();
+```
+
+### Create a `DataLakeFileClient`
+
+Create a `DataLakeFileClient` using a `DataLakeFileSystemClient`.
+
+```java
+DataLakeFileClient fileClient = dataLakeFileSystemClient.getFileClient("myfile");
+```
+
+or
+
+Create a `FileClient` from the builder [`sasToken`](#get-credentials) generated above.
+
+```java
+DataLakeFileClient fileClient = new DataLakePathClientBuilder()
+        .endpoint("<your-storage-dfs-url>")
+        .sasToken("<your-sasToken>")
+        .fileSystemName("myfilesystem")
+        .pathName("myfile")
+        .buildClient();
+```
+
+### Create a file system
+
+Create a file system using a `DataLakeServiceClient`.
+
+```java
+dataLakeServiceClient.createFileSystem("myfilesystem");
+```
+
+or
+
+Create a container using a `DataLakeFileSystemClient`.
+
+```java
+dataLakeFileSystemClient.create();
+```
+
+### Upload a file from a stream
+
+Upload from an `InputStream` to a blob using a `DataLakeFileClient` generated from a `DataLakeFileSystemClient`.
+
+```java
+DataLakeFileClient fileClient = dataLakeFileSystemClient.getFileClient("myfile");
+fileClient.create();
+String dataSample = "samples";
+try (ByteArrayInputStream dataStream = new ByteArrayInputStream(dataSample.getBytes())) {
+    fileClient.append(dataStream, 0, dataSample.length());
+}
+fileClient.flush(dataSample.length());
+```
+
+### Download a file to a stream
+
+Download a file to an `OutputStream` using a `DataLakeFileClient`.
+
+```java
+try(ByteArrayOutputStream outputStream = new ByteArrayOutputStream()) {
+    fileClient.read(outputStream);
+}
+```
+
+### Enumerate paths
+
+Enumerating all paths using a `DataLakeFileSystemClient`.
+
+```java
+dataLakeFileSystemClient.listPaths()
+        .forEach(
+            pathItem -> System.out.println("This is the path name: " + pathItem.getName())
+        );
+```
+
+### Authenticate with Azure Identity
+
+The [Azure Identity library][identity] provides Azure Active Directory support for authenticating with Azure Storage.
+
+```java
+DataLakeServiceClient storageClient = new DataLakeServiceClientBuilder()
+        .endpoint(endpoint)
+        .credential(new DefaultAzureCredentialBuilder().build())
+        .buildClient();
+```
+
 ## Troubleshooting
 
+When interacting with data lake using this Java client library, errors returned by the service correspond to the same HTTP
+status codes returned for [REST API][error_codes] requests. For example, if you try to retrieve a file system or path that
+doesn't exist in your Storage Account, a `404` error is returned, indicating `Not Found`.
+
 ## Next steps
 
+Several Storage datalake  Java SDK samples are available to you in the SDK's GitHub repository. 
+
 ## Contributing
-This project welcomes contributions and suggestions. Most contributions require you to agree to a Contributor License Agreement (CLA) declaring that you have the right to, and actually do, grant us the rights to use your contribution. For details, visit https://cla.microsoft.com.
+
+This project welcomes contributions and suggestions. Most contributions require you to agree to a [Contributor License Agreement (CLA)][cla] declaring that you have the right to, and actually do, grant us the rights to use your contribution.
 
 When you submit a pull request, a CLA-bot will automatically determine whether you need to provide a CLA and decorate the PR appropriately (e.g., label, comment). Simply follow the instructions provided by the bot. You will only need to do this once across all repos using our CLA.
 
-This project has adopted the [Microsoft Open Source Code of Conduct](https://opensource.microsoft.com/codeofconduct/). For more information see the Code of Conduct FAQ or contact [email protected] with any additional questions or comments.
+This project has adopted the [Microsoft Open Source Code of Conduct][coc]. For more information see the [Code of Conduct FAQ][coc_faq] or contact [[email protected]][coc_contact] with any additional questions or comments.
+
+<!-- LINKS -->
+[source]: src
+[samples_readme]: src/samples/README.md
+[docs]: http://azure.github.io/azure-sdk-for-java/
+[rest_docs]: https://docs.microsoft.com/en-us/rest/api/storageservices/data-lake-storage-gen2
+[product_docs]: https://docs.microsoft.com/en-us/azure/storage/blobs/data-lake-storage-introduction
+[sas_token]: https://docs.microsoft.com/azure/storage/common/storage-dotnet-shared-access-signature-part-1
+[jdk]: https://docs.microsoft.com/java/azure/jdk/
+[azure_subscription]: https://azure.microsoft.com/free/
+[storage_account]: https://docs.microsoft.com/azure/storage/common/storage-quickstart-create-account?tabs=azure-portal
+[storage_account_create_cli]: https://docs.microsoft.com/azure/storage/common/storage-quickstart-create-account?tabs=azure-cli
+[storage_account_create_portal]: https://docs.microsoft.com/azure/storage/common/storage-quickstart-create-account?tabs=azure-portal
+[identity]: https://github.com/Azure/azure-sdk-for-java/blob/master/sdk/identity/azure-identity/README.md
+[samples]: src/samples
+[cla]: https://cla.microsoft.com
+[coc]: https://opensource.microsoft.com/codeofconduct/
+[coc_faq]: https://opensource.microsoft.com/codeofconduct/faq/
+[coc_contact]: mailto:[email protected]
 
-![Impressions](https://azure-sdk-impressions.azurewebsites.net/api/impressions/azure-sdk-for-java/sdk/tracing/README.png)
+![Impressions](https://azure-sdk-impressions.azurewebsites.net/api/impressions/azure-sdk-for-java/sdk/storage/azure-storage-file-data-lake/README.png)