Manage Azure Data Lake Analytics using a Java app

This article describes how to manage Azure Data Lake Analytics accounts, data sources, users, and jobs using an app written using the Azure Java SDK.

Prerequisites

  • Java Development Kit (JDK) 8 (using Java version 1.8).
  • IntelliJ or another suitable Java development environment. The instructions in this document use IntelliJ.
  • Create an Azure Active Directory (AAD) application and retrieve its Client ID, Tenant ID, and Key. For more information about AAD applications and instructions on how to get a client ID, see Create Active Directory application and service principal using portal. The Reply URI and Key is available from the portal once you have the application created and key generated.

Authenticating using Azure Active Directory

The code following snippet provides code for non-interactive authentication, where the application provides its own credentials.

Create a Java application

  1. Open IntelliJ and create a Java project using the Command-Line App template.
  2. Right-click on the project on the left-hand side of your screen and click Add Framework Support. Choose Maven and click OK.
  3. Open the newly created "pom.xml" file and add the following snippet of text between the </version> tag and the </project> tag:
<dependencies>
    <dependency>
        <groupId>com.microsoft.azure</groupId>
        <artifactId>azure-client-authentication</artifactId>
        <version>1.6.12</version>
    </dependency>
    <dependency>
        <groupId>com.microsoft.azure</groupId>
        <artifactId>azure-client-runtime</artifactId>
        <version>1.6.12</version>
    </dependency>
    <dependency>
        <groupId>com.microsoft.rest</groupId>
        <artifactId>client-runtime</artifactId>
        <version>1.6.12</version>
    </dependency>
    <dependency>
        <groupId>com.microsoft.azure</groupId>
        <artifactId>azure-mgmt-datalake-store</artifactId>
        <version>1.22.0</version>
    </dependency>
    <dependency>
        <groupId>com.microsoft.azure</groupId>
        <artifactId>azure-mgmt-datalake-analytics</artifactId>
        <version>1.22.0</version>
    </dependency>
    <dependency>
        <groupId>com.microsoft.azure</groupId>
        <artifactId>azure-data-lake-store-sdk</artifactId>
        <version>2.3.6</version>
        <exclusions>
            <exclusion>
                <groupId>com.fasterxml.jackson.core</groupId>
                <artifactId>jackson-core</artifactId>
            </exclusion>
        </exclusions>
    </dependency>
</dependencies>

Go to File > Settings > Build > Execution > Deployment. Select Build Tools > Maven > Importing. Then check Import Maven projects automatically.

Open Main.java and replace the existing code block with the following code:

import com.microsoft.azure.CloudException;
import com.microsoft.azure.credentials.ApplicationTokenCredentials;
import com.microsoft.azure.datalake.store.*;
import com.microsoft.azure.datalake.store.oauth2.*;
import com.microsoft.azure.management.datalake.analytics.implementation.*;
import com.microsoft.azure.management.datalake.store.*;
import com.microsoft.azure.management.datalake.store.implementation.*;
import com.microsoft.azure.management.datalake.store.models.*;
import com.microsoft.azure.management.datalake.analytics.*;
import com.microsoft.azure.management.datalake.analytics.models.*;
import com.microsoft.rest.credentials.ServiceClientCredentials;

import java.io.*;
import java.nio.charset.Charset;
import java.util.ArrayList;
import java.util.UUID;
import java.util.List;

public class Main {
    private static String _adlsAccountName;
    private static String _adlaAccountName;
    private static String _resourceGroupName;
    private static String _location;

    private static String _tenantId;
    private static String _subscriptionId;
    private static String _clientId;
    private static String _clientSecret;

    private static DataLakeStoreAccountManagementClient _adlsClient;
    private static ADLStoreClient _adlsStoreClient;
    private static DataLakeAnalyticsAccountManagementClient _adlaClient;
    private static DataLakeAnalyticsJobManagementClient _adlaJobClient;

    public static void main(String[] args) throws Exception {
        _adlsAccountName = "<DATA-LAKE-STORE-NAME>";
        _adlaAccountName = "<DATA-LAKE-ANALYTICS-NAME>";
        _resourceGroupName = "<RESOURCE-GROUP-NAME>";
        _location = "East US 2";

        _tenantId = "<TENANT-ID>";
        _subscriptionId =  "<SUBSCRIPTION-ID>";
        _clientId = "<CLIENT-ID>";

        _clientSecret = "<CLIENT-SECRET>";

        String localFolderPath = "C:\\local_path\\";

        // ----------------------------------------
        // Authenticate
        // ----------------------------------------
        ApplicationTokenCredentials creds = new ApplicationTokenCredentials(_clientId, _tenantId, _clientSecret, null);
        SetupClients(creds);

        // ----------------------------------------
        // List Data Lake Store and Analytics accounts that this app can access
        // ----------------------------------------
        System.out.println(String.format("All ADL Store accounts that this app can access in subscription %s:", _subscriptionId));
        List<DataLakeStoreAccountBasic> adlsListResult = _adlsClient.accounts().list();
        for (DataLakeStoreAccountBasic acct : adlsListResult) {
            System.out.println(acct.name());
        }

        System.out.println(String.format("All ADL Analytics accounts that this app can access in subscription %s:", _subscriptionId));
        List<DataLakeAnalyticsAccountBasic> adlaListResult = _adlaClient.accounts().list();
        for (DataLakeAnalyticsAccountBasic acct : adlaListResult) {
            System.out.println(acct.name());
        }
        WaitForNewline("Accounts displayed.", "Creating files.");

        // ----------------------------------------
        // Create a file in Data Lake Store: input1.csv
        // ----------------------------------------
        CreateFile("/input1.csv", "123,abc", true);
        WaitForNewline("File created.", "Submitting a job.");

        // ----------------------------------------
        // Submit a job to Data Lake Analytics
        // ----------------------------------------
        String script = "@input = EXTRACT Row1 string, Row2 string FROM \"/input1.csv\" USING Extractors.Csv(); OUTPUT @input TO @\"/output1.csv\" USING Outputters.Csv();";
        UUID jobId = SubmitJobByScript(script, "testJob");
        WaitForNewline("Job submitted.", "Getting job status.");

        // ----------------------------------------
        // Wait for job completion and output job status
        // ----------------------------------------
        System.out.println(String.format("Job status: %s", GetJobStatus(jobId)));
        System.out.println("Waiting for job completion.");
        WaitForJob(jobId);
        System.out.println(String.format("Job status: %s", GetJobStatus(jobId)));
        WaitForNewline("Job completed.", "Downloading job output.");

        // ----------------------------------------
        // Download job output from Data Lake Store
        // ----------------------------------------
        DownloadFile("/output1.csv", localFolderPath + "output1.csv");
        WaitForNewline("Job output downloaded.", "Deleting file.");

        DeleteFile("/output1.csv");
        WaitForNewline("File deleted.", "Done.");
    }

    public static void SetupClients(ServiceClientCredentials creds) {
        _adlsClient = new DataLakeStoreAccountManagementClientImpl(creds);
        _adlaClient = new DataLakeAnalyticsAccountManagementClientImpl(creds);
        _adlaJobClient = new DataLakeAnalyticsJobManagementClientImpl(creds);
        _adlsClient.withSubscriptionId(_subscriptionId);
        _adlaClient.withSubscriptionId(_subscriptionId);

        String authEndpoint = "https://login.microsoftonline.com/" + _tenantId + "/oauth2/token";
        AccessTokenProvider provider = new ClientCredsTokenProvider(authEndpoint, _clientId, _clientSecret);
        _adlsStoreClient = ADLStoreClient.createClient(_adlsAccountName + ".azuredatalakestore.net", provider);
    }

    public static void WaitForNewline(String reason, String nextAction) {
        if (nextAction == null)
            nextAction = "";

        System.out.println(reason + "\r\nPress ENTER to continue...");
        try {
            System.in.read();
        } catch (Exception e) {
        }

        if (!nextAction.isEmpty()) {
            System.out.println(nextAction);
        }
    }

    // Create accounts
    public static void CreateAccounts() throws InterruptedException, CloudException, IOException {
        // Create ADLS account
        CreateDataLakeStoreAccountParameters adlsParameters = new CreateDataLakeStoreAccountParameters();
        adlsParameters.withLocation(_location);

        _adlsClient.accounts().create(_resourceGroupName, _adlsAccountName, adlsParameters);

        // Create ADLA account
        AddDataLakeStoreWithAccountParameters adlsInfo = new AddDataLakeStoreWithAccountParameters();
        adlsInfo.withName(_adlsAccountName);

        List<AddDataLakeStoreWithAccountParameters> adlsInfoList = new ArrayList<>();
        adlsInfoList.add(adlsInfo);

        CreateDataLakeAnalyticsAccountParameters adlaParameters = new CreateDataLakeAnalyticsAccountParameters();
        adlaParameters.withLocation(_location);
        adlaParameters.withDefaultDataLakeStoreAccount(_adlsAccountName);
        adlaParameters.withDataLakeStoreAccounts(adlsInfoList);

        _adlaClient.accounts().create(_resourceGroupName, _adlaAccountName, adlaParameters);
    }

    // Create a file
    public static void CreateFile(String path, String contents, boolean force) throws IOException, CloudException {
        byte[] bytesContents = contents.getBytes();

        ADLFileOutputStream stream = _adlsStoreClient.createFile(path, IfExists.OVERWRITE, "777", force);
        stream.write(bytesContents);
        stream.close();
    }

    // Delete a file
    public static void DeleteFile(String filePath) throws IOException, CloudException {
        _adlsStoreClient.delete(filePath);
    }

    // Download a file
    private static void DownloadFile(String srcPath, String destPath) throws IOException, CloudException {
        ADLFileInputStream stream = _adlsStoreClient.getReadStream(srcPath);

        PrintWriter pWriter = new PrintWriter(destPath, Charset.defaultCharset().name());

        String fileContents = "";
        if (stream != null) {
            Writer writer = new StringWriter();

            char[] buffer = new char[1024];
            try {
                Reader reader = new BufferedReader(
                        new InputStreamReader(stream, "UTF-8"));
                int n;
                while ((n = reader.read(buffer)) != -1) {
                    writer.write(buffer, 0, n);
                }
            } finally {
                stream.close();
            }
            fileContents = writer.toString();
        }

        pWriter.println(fileContents);
        pWriter.close();
    }

    // Submit a U-SQL job
    private static UUID SubmitJobByScript(String script, String jobName) throws IOException, CloudException {
        UUID jobId = java.util.UUID.randomUUID();
        CreateJobProperties properties = new CreateUSqlJobProperties();
        properties.withScript(script);
        CreateJobParameters parameters = new CreateJobParameters();
        parameters.withName(jobName);
        parameters.withType(JobType.USQL);
        parameters.withProperties(properties);

        JobInformation jobInfo = _adlaJobClient.jobs().create(_adlaAccountName, jobId, parameters);

        return jobInfo.jobId();
    }

    // Wait for job completion
    private static JobResult WaitForJob(UUID jobId) throws IOException, CloudException {
        JobInformation jobInfo = _adlaJobClient.jobs().get(_adlaAccountName, jobId);
        while (jobInfo.state() != JobState.ENDED) {
            jobInfo = _adlaJobClient.jobs().get(_adlaAccountName, jobId);
        }
        return jobInfo.result();
    }

    // Retrieve job status
    private static String GetJobStatus(UUID jobId) throws IOException, CloudException {
        JobInformation jobInfo = _adlaJobClient.jobs().get(_adlaAccountName, jobId);
        return jobInfo.state().toString();
    }
}

Provide the values for parameters called out in the code snippet:

  • localFolderPath
  • _adlaAccountName
  • _adlsAccountName
  • _resourceGroupName
  • _tenantId
  • _subId
  • _clientId
  • _clientSecret

Next steps