Enable MSICrdentials in v2: Merging msi credentials for app-service a…

…nd vm (Azure#474)

* Enable MSICrdentials in v2: Merging msi credentials for app-service and vm

* Removing unused AppServiceMSICredentials and using binary expotential backoff algo retry

azure-client-authentication/src/main/java/com/microsoft/azure/v2/credentials/MSIConfigurationForAppService.java

@@ -0,0 +1,117 @@
+/**
+ * Copyright (c) Microsoft Corporation. All rights reserved.
+ * Licensed under the MIT License. See License.txt in the project root for
+ * license information.
+ */
+package com.microsoft.azure.v2.credentials;
+
+import com.microsoft.azure.v2.AzureEnvironment;
+
+/**
+ * Defines the configuration to be used for retrieving access token from
+ * within an app-service with system assigned MSI enabled.
+ */
+public class MSIConfigurationForAppService {
+    private final AzureEnvironment environment;
+    private String resource;
+    private String msiEndpoint;
+    private String msiSecret;
+
+    /**
+     * Creates MSIConfigurationForAppService.
+     *
+     * @param environment azure environment
+     */
+    public MSIConfigurationForAppService(AzureEnvironment environment) {
+        this.environment = environment;
+    }
+
+    /**
+     * Creates MSIConfigurationForAppService.
+     */
+    public MSIConfigurationForAppService() {
+        this(AzureEnvironment.AZURE);
+    }
+
+    /**
+     * @return the azure environment.
+     */
+    public AzureEnvironment azureEnvironment() {
+        return this.environment;
+    }
+    /**
+     * @return the audience identifying who will consume the token.
+     */
+    public String resource() {
+        if (this.resource == null) {
+            this.resource = this.environment.managementEndpoint();
+        }
+        return this.resource;
+    }
+    /**
+     * @return the endpoint from which token needs to be retrieved.
+     */
+    public String msiEndpoint() {
+        if (this.msiEndpoint == null) {
+            this.msiEndpoint = System.getenv("MSI_ENDPOINT");
+        }
+        return this.msiEndpoint;
+    }
+    /**
+     * @return the secret to use to retrieve the token.
+     */
+    public String msiSecret() {
+        if (this.msiSecret == null) {
+            this.msiSecret = System.getenv("MSI_SECRET");
+        }
+        return this.msiSecret;
+    }
+    /**
+     * Specifies the token audience.
+     *
+     * @param resource the audience of the token.
+     *
+     * @return MSIConfigurationForAppService
+     */
+    public MSIConfigurationForAppService withResource(String resource) {
+        this.resource = resource;
+        return this;
+    }
+    /**
+     * Specifies the endpoint from which token needs to retrieved.
+     *
+     * @param msiEndpoint the token endpoint.
+     *
+     * @return MSIConfigurationForAppService
+     */
+    public MSIConfigurationForAppService withMsiEndpoint(String msiEndpoint) {
+        this.msiSecret = msiEndpoint;
+        return this;
+    }
+    /**
+     * Specifies secret to use to retrieve the token.
+     *
+     * @param msiSecret the secret.
+     *
+     * @return MSIConfigurationForAppService
+     */
+    public MSIConfigurationForAppService withMsiSecret(String msiSecret) {
+        this.msiSecret = msiSecret;
+        return this;
+    }
+
+    @Override
+    public MSIConfigurationForAppService clone() {
+        MSIConfigurationForAppService copy = new MSIConfigurationForAppService(this.azureEnvironment());
+        if (this.resource() != null) {
+            copy.withResource(this.resource());
+        }
+        if (this.msiEndpoint() != null) {
+            copy.withMsiEndpoint(this.msiEndpoint());
+        }
+        if (this.msiSecret() != null) {
+            copy.withMsiSecret(this.msiSecret());
+        }
+        return copy;
+    }
+}

azure-client-authentication/src/main/java/com/microsoft/azure/v2/credentials/MSIConfigurationForVirtualMachine.java

@@ -0,0 +1,216 @@
+/**
+ * Copyright (c) Microsoft Corporation. All rights reserved.
+ * Licensed under the MIT License. See License.txt in the project root for
+ * license information.
+ */
+package com.microsoft.azure.v2.credentials;
+
+import com.microsoft.azure.v2.AzureEnvironment;
+
+/**
+ * Defines the configuration to be used for retrieving access token from
+ * within a VM with user assigned or system assigned MSI enabled.
+ */
+public class MSIConfigurationForVirtualMachine {
+    private final AzureEnvironment environment;
+    private String resource;
+    private MSITokenSource tokenSource;
+    private String objectId;
+    private String clientId;
+    private String identityId;
+    private Integer msiPort = null;
+    private int maxRetry = -1;
+
+    /**
+     * Creates MSIConfigurationForVirtualMachine.
+     *
+     * @param environment azure environment
+     */
+    public MSIConfigurationForVirtualMachine(AzureEnvironment environment) {
+        this.environment = environment;
+    }
+
+    /**
+     * Creates MSIConfigurationForVirtualMachine.
+     */
+    public MSIConfigurationForVirtualMachine() {
+        this(AzureEnvironment.AZURE);
+    }
+
+    /**
+     * @return the azure environment.
+     */
+    public AzureEnvironment azureEnvironment() {
+        return this.environment;
+    }
+
+    /**
+     * @return the token retrieval source (either MSI extension running in VM or IMDS service).
+     */
+    public MSITokenSource tokenSource() {
+        if (this.tokenSource == null) {
+            this.tokenSource = MSITokenSource.IMDS_ENDPOINT;
+        }
+        return this.tokenSource;
+    }
+    /**
+     * @return the audience identifying who will consume the token.
+     */
+    public String resource() {
+        if (this.resource == null) {
+            this.resource = this.environment.managementEndpoint();
+        }
+        return this.resource;
+    }
+    /**
+     * @return the principal id of user assigned or system assigned identity.
+     */
+    public String objectId() {
+        return this.objectId;
+    }
+    /**
+     * @return the client id of user assigned or system assigned identity.
+     */
+    public String clientId() {
+        return this.clientId;
+    }
+    /**
+     * @return the ARM resource id of the user assigned identity resource.
+     */
+    public String identityId() {
+        return this.identityId;
+    }
+    /**
+     * @return the port of token retrieval service running in the extension.
+     */
+    public int msiPort() {
+        if (this.msiPort == null) {
+            this.msiPort = 50342;
+        }
+        return this.msiPort;
+    }
+
+    /**
+     * @return the maximum retries allowed.
+     */
+    public int maxRetry() {
+        return this.maxRetry;
+    }
+
+    /**
+     * Specifies the token retrieval source.
+     *
+     * @param tokenSource the source of token
+     *
+     * @return MSIConfigurationForVirtualMachine
+     */
+    public MSIConfigurationForVirtualMachine withTokenSource(MSITokenSource tokenSource) {
+        this.tokenSource = tokenSource;
+        return this;
+    }
+
+    /**
+     * Specifies the token audience.
+     *
+     * @param resource the audience of the token.
+     *
+     * @return MSIConfigurationForVirtualMachine
+     */
+    public MSIConfigurationForVirtualMachine withResource(String resource) {
+        this.resource = resource;
+        return this;
+    }
+
+    /**
+     * specifies the principal id of user assigned or system assigned identity.
+     *
+     * @param objectId the object (principal) id
+     * @return MSIConfigurationForVirtualMachine
+     */
+    public MSIConfigurationForVirtualMachine withObjectId(String objectId) {
+        this.objectId = objectId;
+        return this;
+    }
+
+    /**
+     * Specifies the client id of user assigned or system assigned identity.
+     *
+     * @param clientId the client id
+     * @return MSIConfigurationForVirtualMachine
+     */
+    public MSIConfigurationForVirtualMachine withClientId(String clientId) {
+        this.clientId = clientId;
+        return this;
+    }
+
+    /**
+     * Specifies the ARM resource id of the user assigned identity resource.
+     *
+     * @param identityId the identity ARM id
+     * @return MSIConfigurationForVirtualMachine
+     */
+    public MSIConfigurationForVirtualMachine withIdentityId(String identityId) {
+        this.identityId = identityId;
+        return this;
+    }
+
+    /**
+     * Specifies the port of token retrieval msi extension service.
+     *
+     * @param msiPort the port
+     * @return MSIConfigurationForVirtualMachine
+     */
+    public MSIConfigurationForVirtualMachine withMsiPort(int msiPort) {
+        this.msiPort = msiPort;
+        return this;
+    }
+
+    /**
+     * Specifies the the maximum retries allowed.
+     *
+     * @param maxRetry max retry count
+     * @return MSIConfigurationForVirtualMachine
+     */
+    public MSIConfigurationForVirtualMachine withMaxRetry(int maxRetry) {
+        this.maxRetry = maxRetry;
+        return this;
+    }
+
+    @Override
+    public MSIConfigurationForVirtualMachine clone() {
+        MSIConfigurationForVirtualMachine copy = new MSIConfigurationForVirtualMachine(this.azureEnvironment());
+        if (this.clientId() != null) {
+            copy.withClientId(this.clientId());
+        }
+        if (this.identityId() != null) {
+            copy.withIdentityId(this.identityId());
+        }
+        if (this.objectId() != null) {
+            copy.withObjectId(this.objectId());
+        }
+        if (this.resource() != null) {
+            copy.withResource(this.resource());
+        }
+        if (this.tokenSource() != null) {
+            copy.withTokenSource(this.tokenSource());
+        }
+        copy.withMaxRetry(this.maxRetry());
+        copy.withMsiPort(this.msiPort());
+        return copy;
+    }
+
+
+    /**
+     * The source of MSI token.
+     */
+    public enum MSITokenSource {
+        /**
+         * Indicate that token should be retrieved from MSI extension installed in the VM.
+         */
+        MSI_EXTENSION,
+        /**
+         * Indicate that token should be retrieved from IMDS service.
+         */
+        IMDS_ENDPOINT
+    }
+}