feat(prov-dev, deps): Add support for retry-after headers from DPS

deps/src/main/java/com/microsoft/azure/sdk/iot/deps/transport/amqp/AmqpMessage.java

@@ -72,6 +72,23 @@ public void setApplicationProperty(Map<String, Object> userProperties)
         this.messageImpl.setApplicationProperties(applicationProperties);
     }
 
+    /**
+     * Set the application property for the message
+     * @return Map of properties
+     */
+    public Map<String, Object> getApplicationProperty()
+    {
+        ApplicationProperties appProperty = this.messageImpl.getApplicationProperties();
+        if (appProperty == null)
+        {
+            return null;
+        }
+        else
+        {
+            return appProperty.getValue();
+        }
+    }
+
     /**
      * Sets the data value
      * @param data the {@code byte[]} to be decoded

deps/src/main/java/com/microsoft/azure/sdk/iot/deps/transport/http/HttpResponse.java

@@ -103,6 +103,12 @@ public String getHeaderField(String field)
         return values;
     }
 
+    public boolean isFieldAvailable(String field)
+    {
+        String canonicalizedField = canonicalizeFieldName(field);
+        return this.headerFields.containsKey(canonicalizedField);
+    }
+
     /**
      * Getter for the header fields.
      *

provisioning/provisioning-device-client/src/main/java/com/microsoft/azure/sdk/iot/provisioning/device/internal/contract/ProvisioningDeviceClientContract.java

@@ -17,6 +17,24 @@
 
 public abstract class ProvisioningDeviceClientContract
 {
+    private int retryValue = DEFAULT_RETRY_AFTER_VALUE;
+    protected static final String RETRY_AFTER = "retry-after";
+    private static final Integer DEFAULT_RETRY_AFTER_VALUE = 2;
+    private static final Integer MAX_PROV_GET_THROTTLE_TIME = 5;
+
+    protected void setRetrieveRetryAfterValue(String protocolRetryValue)
+    {
+        if (protocolRetryValue != null && !protocolRetryValue.isEmpty())
+        {
+            retryValue = Integer.parseInt(protocolRetryValue);
+            // ensure the value is between the tolerances
+            if (retryValue < DEFAULT_RETRY_AFTER_VALUE || retryValue > MAX_PROV_GET_THROTTLE_TIME)
+            {
+                retryValue = DEFAULT_RETRY_AFTER_VALUE;
+            }
+        }
+    }
+
     /**
      * Static method to create contracts with the service over the specified protocol
      * @param provisioningDeviceClientConfig Config used for provisioning
@@ -58,4 +76,13 @@ public static ProvisioningDeviceClientContract createProvisioningContract(Provis
     public abstract void authenticateWithProvisioningService(RequestData requestData, ResponseCallback responseCallback, Object dpsAuthorizationCallbackContext) throws ProvisioningDeviceClientException;
     public abstract void getRegistrationStatus(RequestData requestData, ResponseCallback responseCallback, Object dpsAuthorizationCallbackContext) throws ProvisioningDeviceClientException;
     public abstract void close() throws ProvisioningDeviceConnectionException;
+
+    /**
+     * Method to get the DPS retry after value
+     * @return integer value of the number of milliseconds to wait to call dps service
+     */
+    public int getRetryValue()
+    {
+        return this.retryValue*1000;
+    }
 }

provisioning/provisioning-device-client/src/main/java/com/microsoft/azure/sdk/iot/provisioning/device/internal/contract/amqp/ContractAPIAmqp.java

@@ -18,6 +18,7 @@
 
 import javax.net.ssl.SSLContext;
 import java.io.IOException;
+import java.util.Map;
 
 public class ContractAPIAmqp extends ProvisioningDeviceClientContract
 {
@@ -27,6 +28,18 @@ public class ContractAPIAmqp extends ProvisioningDeviceClientContract
     private String idScope;
     private SaslHandler amqpSaslHandler;
 
+    private void processRetryAfterValue(Map<String, Object> appProperties)
+    {
+        if (appProperties != null)
+        {
+            if (appProperties.containsKey(RETRY_AFTER))
+            {
+                Object retryAfterValue = appProperties.get(RETRY_AFTER);
+                setRetrieveRetryAfterValue(retryAfterValue.toString());
+            }
+        }
+    }
+
     /**
      * This constructor creates an instance of DpsAPIAmqps class and initializes member variables
      * @param provisioningDeviceClientConfig Config used for provisioning Cannot be {@code null}.
@@ -173,6 +186,8 @@ public synchronized void authenticateWithProvisioningService(RequestData request
 
         // SRS_ContractAPIAmqp_07_005: [This method shall send an AMQP message with the property of iotdps-register.]
         this.provisioningAmqpOperations.sendRegisterMessage(responseCallback, callbackContext, payload);
+
+        processRetryAfterValue(this.provisioningAmqpOperations.getAmqpMessageProperties());
     }
 
     /**

provisioning/provisioning-device-client/src/main/java/com/microsoft/azure/sdk/iot/provisioning/device/internal/contract/amqp/ProvisioningAmqpOperations.java

@@ -35,6 +35,7 @@ public class ProvisioningAmqpOperations extends AmqpDeviceOperations implements
     private final Queue<AmqpMessage> receivedMessages = new LinkedBlockingQueue<>();
     private final ObjectLock receiveLock = new ObjectLock();
 
+    private Map<String, Object> messageAppProperties;
     private String idScope;
     private String hostName;
 
@@ -94,6 +95,9 @@ private void retrieveAmqpMessage(ResponseCallback responseCallback, Object callb
         if (this.receivedMessages.size() > 0)
         {
             AmqpMessage message = this.receivedMessages.remove();
+
+            // Need to keep property around to get the retry-after value
+            this.messageAppProperties = message.getApplicationProperty();
             byte[] msgData = message.getAmqpBody();
             if (msgData != null)
             {
@@ -286,6 +290,15 @@ public void sendRegisterMessage(ResponseCallback responseCallback, Object callba
         }
     }
 
+    /**
+     * Returns the message properties of the current message
+     * @return Map of application properties
+     */
+    public Map<String, Object> getAmqpMessageProperties()
+    {
+        return this.messageAppProperties;
+    }
+
     /**
      * connectionEstablished Unused
      */