Add SDK functionality to make it easier to deserialize/consume EventGrid events

eventgrid/data-plane/src/main/java/com/microsoft/azure/eventgrid/customization/EventGridSubscriber.java

@@ -0,0 +1,185 @@
+/**
+ * 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.eventgrid.customization;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.microsoft.azure.eventgrid.models.EventGridEvent;
+import com.microsoft.azure.management.apigeneration.Beta;
+import com.microsoft.azure.serializer.AzureJacksonAdapter;
+import com.microsoft.rest.protocol.SerializerAdapter;
+
+import java.io.IOException;
+import java.lang.reflect.Field;
+import java.lang.reflect.Type;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Set;
+
+/**
+ * The type that can be used to de-serialize eventgrid events.
+ */
+@Beta
+public class EventGridSubscriber {
+    /**
+     * The default adapter to be used for de-serializing the events.
+     */
+    private final AzureJacksonAdapter defaultSerializerAdapter;
+    /**
+     * The map containing user defined mapping of eventType to Java model type.
+     */
+    private Map<String, Type> eventTypeToEventDataMapping;
+
+    /**
+     * Creates EventGridSubscriber with default de-serializer.
+     */
+    @Beta
+    public EventGridSubscriber() {
+        this.defaultSerializerAdapter = new AzureJacksonAdapter();
+        this.eventTypeToEventDataMapping =  new HashMap<>();
+    }
+
+    /**
+     * Add a custom event mapping. If a mapping with same eventType exists then the old eventDataType is replaced by
+     * the specified eventDataType.
+     *
+     * @param eventType the event type name.
+     * @param eventDataType type of the Java model that the event type name mapped to.
+     */
+    @Beta
+    public void putCustomEventMapping(final String eventType, final Type eventDataType) {
+        if (eventType == null || eventType.isEmpty()) {
+            throw new IllegalArgumentException("eventType parameter is required and cannot be null or empty");
+        }
+        if (eventDataType == null) {
+            throw new IllegalArgumentException("eventDataType parameter is required and cannot be null");
+        }
+        this.eventTypeToEventDataMapping.put(canonicalizeEventType(eventType), eventDataType);
+    }
+
+    /**
+     * Get type of the Java model that is mapped to the given eventType.
+     *
+     * @param eventType the event type name.
+     * @return type of the Java model if mapping exists, null otherwise.
+     */
+    @Beta
+    public Type getCustomEventMapping(final String eventType) {
+        if (!containsCustomEventMappingFor(eventType)) {
+            return null;
+        } else {
+            return this.eventTypeToEventDataMapping.get(canonicalizeEventType(eventType));
+        }
+    }
+
+    /**
+     * @return get all registered custom event mappings.
+     */
+    @Beta
+    public Set<Map.Entry<String, Type>> getAllCustomEventMappings() {
+        return Collections.unmodifiableSet(this.eventTypeToEventDataMapping.entrySet());
+    }
+
+    /**
+     * Removes the mapping with the given eventType.
+     *
+     * @param eventType the event type name.
+     * @return true if the mapping exists and removed, false if mapping does not exists.
+     */
+    @Beta
+    public boolean removeCustomEventMapping(final String eventType) {
+        if (!containsCustomEventMappingFor(eventType)) {
+            return false;
+        } else {
+            this.eventTypeToEventDataMapping.remove(canonicalizeEventType(eventType));
+            return true;
+        }
+    }
+
+    /**
+     * Checks if an event mapping with the given eventType exists.
+     *
+     * @param eventType the event type name.
+     * @return true if the mapping exists, false otherwise.
+     */
+    @Beta
+    public boolean containsCustomEventMappingFor(final String eventType) {
+        if (eventType == null || eventType.isEmpty()) {
+            return false;
+        } else {
+            return this.eventTypeToEventDataMapping.containsKey(canonicalizeEventType(eventType));
+        }
+    }
+
+    /**
+     * De-serialize the events in the given requested content using default de-serializer.
+     *
+     * @param requestContent the request content in string format.
+     * @return De-serialized events.
+     *
+     * @throws IOException
+     */
+    @Beta
+    public EventGridEvent[] deserializeEventGridEvents(final String requestContent) throws IOException {
+        return this.deserializeEventGridEvents(requestContent, this.defaultSerializerAdapter);
+    }
+
+    /**
+     * De-serialize the events in the given requested content using the provided de-serializer.
+     *
+     * @param requestContent the request content as string.
+     * @param serializerAdapter the de-serializer.
+     * @return de-serialized events.
+     * @throws IOException
+     */
+    @Beta
+    public EventGridEvent[] deserializeEventGridEvents(final String requestContent, final SerializerAdapter<ObjectMapper> serializerAdapter) throws IOException {
+        EventGridEvent[] eventGridEvents = serializerAdapter.<EventGridEvent[]>deserialize(requestContent, EventGridEvent[].class);
+        for (EventGridEvent receivedEvent : eventGridEvents) {
+            if (receivedEvent.data() == null) {
+                continue;
+            } else {
+                final String eventType = receivedEvent.eventType();
+                final Type eventDataType;
+                if (SystemEventTypeMappings.containsMappingFor(eventType)) {
+                    eventDataType = SystemEventTypeMappings.getMapping(eventType);
+                } else if (containsCustomEventMappingFor(eventType)) {
+                    eventDataType = getCustomEventMapping(eventType);
+                } else {
+                    eventDataType = null;
+                }
+                if (eventDataType != null) {
+                    final String eventDataAsString = serializerAdapter.serializeRaw(receivedEvent.data());
+                    final Object eventData = serializerAdapter.<Object>deserialize(eventDataAsString, eventDataType);
+                    setEventData(receivedEvent, eventData);
+                }
+            }
+        }
+        return eventGridEvents;
+    }
+
+    private static void setEventData(EventGridEvent event, final Object data) {
+        // This reflection based way to set the data field needs to be removed once
+        // we expose a wither in EventGridEvent to set the data. (Check swagger + codegen)
+        try {
+            Field dataField = event.getClass().getDeclaredField("data");
+            dataField.setAccessible(true);
+            dataField.set(event, data);
+        } catch (NoSuchFieldException nsfe) {
+            throw new RuntimeException(nsfe);
+        } catch (IllegalAccessException iae) {
+            throw new RuntimeException(iae);
+        }
+    }
+
+    private static String canonicalizeEventType(final String eventType) {
+        if (eventType == null) {
+            return null;
+        } else {
+            return eventType.toLowerCase();
+        }
+    }
+}

eventgrid/data-plane/src/main/java/com/microsoft/azure/eventgrid/customization/SystemEventTypeMappings.java

@@ -0,0 +1,127 @@
+/**
+ * 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.eventgrid.customization;
+
+import com.microsoft.azure.eventgrid.models.ContainerRegistryImageDeletedEventData;
+import com.microsoft.azure.eventgrid.models.ContainerRegistryImagePushedEventData;
+import com.microsoft.azure.eventgrid.models.EventHubCaptureFileCreatedEventData;
+import com.microsoft.azure.eventgrid.models.IotHubDeviceConnectedEventData;
+import com.microsoft.azure.eventgrid.models.IotHubDeviceCreatedEventData;
+import com.microsoft.azure.eventgrid.models.IotHubDeviceDeletedEventData;
+import com.microsoft.azure.eventgrid.models.IotHubDeviceDisconnectedEventData;
+import com.microsoft.azure.eventgrid.models.MediaJobStateChangeEventData;
+import com.microsoft.azure.eventgrid.models.ResourceActionCancelData;
+import com.microsoft.azure.eventgrid.models.ResourceActionFailureData;
+import com.microsoft.azure.eventgrid.models.ResourceActionSuccessData;
+import com.microsoft.azure.eventgrid.models.ResourceDeleteCancelData;
+import com.microsoft.azure.eventgrid.models.ResourceDeleteFailureData;
+import com.microsoft.azure.eventgrid.models.ResourceDeleteSuccessData;
+import com.microsoft.azure.eventgrid.models.ResourceWriteCancelData;
+import com.microsoft.azure.eventgrid.models.ResourceWriteFailureData;
+import com.microsoft.azure.eventgrid.models.ResourceWriteSuccessData;
+import com.microsoft.azure.eventgrid.models.ServiceBusActiveMessagesAvailableWithNoListenersEventData;
+import com.microsoft.azure.eventgrid.models.ServiceBusDeadletterMessagesAvailableWithNoListenersEventData;
+import com.microsoft.azure.eventgrid.models.StorageBlobCreatedEventData;
+import com.microsoft.azure.eventgrid.models.StorageBlobDeletedEventData;
+import com.microsoft.azure.eventgrid.models.SubscriptionDeletedEventData;
+import com.microsoft.azure.eventgrid.models.SubscriptionValidationEventData;
+import com.microsoft.azure.management.apigeneration.Beta;
+
+import java.lang.reflect.Type;
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * Mapping of system event type name to corresponding type of the Java model.
+ */
+@Beta
+final class SystemEventTypeMappings {
+    /**
+     * The map containing system eventType to Java model type mapping.
+     */
+    private static Map<String, Type> systemEventMappings;
+
+    static {
+        systemEventMappings = new HashMap<>(); // key: eventType, Value:eventDataType
+        //
+        // ContainerRegistry events.
+        systemEventMappings.put(canonicalizeEventType(SystemEventTypes.CONTAINER_REGISTRY_IMAGE_PUSHED_EVENT), ContainerRegistryImagePushedEventData.class);
+        systemEventMappings.put(canonicalizeEventType(SystemEventTypes.CONTAINER_REGISTRY_IMAGE_DELETED_EVENT), ContainerRegistryImageDeletedEventData.class);
+        //
+        // Device events.
+        systemEventMappings.put(canonicalizeEventType(SystemEventTypes.IOT_HUB_DEVICE_CREATED_EVENT), IotHubDeviceCreatedEventData.class);
+        systemEventMappings.put(canonicalizeEventType(SystemEventTypes.IOT_HUB_DEVICE_DELETED_EVENT), IotHubDeviceDeletedEventData.class);
+        systemEventMappings.put(canonicalizeEventType(SystemEventTypes.IOT_HUB_DEVICE_CONNECTED_EVENT), IotHubDeviceConnectedEventData.class);
+        systemEventMappings.put(canonicalizeEventType(SystemEventTypes.IOT_HUB_DEVICE_DISCONNECTED_EVENT), IotHubDeviceDisconnectedEventData.class);
+        //
+        // EventGrid events.
+        systemEventMappings.put(canonicalizeEventType(SystemEventTypes.EVENT_GRID_SUBSCRIPTION_VALIDATION_EVENT), SubscriptionValidationEventData.class);
+        systemEventMappings.put(canonicalizeEventType(SystemEventTypes.EVENT_GRID_SUBSCRIPTION_DELETED_EVENT), SubscriptionDeletedEventData.class);
+        //
+        // Event Hub Events.
+        systemEventMappings.put(canonicalizeEventType(SystemEventTypes.EVENT_HUB_CAPTURE_FILE_CREATED_EVENT), EventHubCaptureFileCreatedEventData.class);
+        //
+        // Media Services events.
+        systemEventMappings.put(canonicalizeEventType(SystemEventTypes.MEDIA_JOB_STATE_CHANGE_EVENT), MediaJobStateChangeEventData.class);
+        //
+        // Resource Manager (Azure Subscription/Resource Group) events.
+        systemEventMappings.put(canonicalizeEventType(SystemEventTypes.RESOURCE_WRITE_SUCCESS_EVENT), ResourceWriteSuccessData.class);
+        systemEventMappings.put(canonicalizeEventType(SystemEventTypes.RESOURCE_WRITE_FAILURE_EVENT), ResourceWriteFailureData.class);
+        systemEventMappings.put(canonicalizeEventType(SystemEventTypes.RESOURCE_WRITE_CANCEL_EVENT), ResourceWriteCancelData.class);
+        systemEventMappings.put(canonicalizeEventType(SystemEventTypes.RESOURCE_DELETE_SUCCESS_EVENT), ResourceDeleteSuccessData.class);
+        systemEventMappings.put(canonicalizeEventType(SystemEventTypes.RESOURCE_DELETE_FAILURE_EVENT), ResourceDeleteFailureData.class);
+        systemEventMappings.put(canonicalizeEventType(SystemEventTypes.RESOURCE_DELETE_CANCEL_EVENT), ResourceDeleteCancelData.class);
+        systemEventMappings.put(canonicalizeEventType(SystemEventTypes.RESOURCE_ACTION_SUCCESS_EVENT), ResourceActionSuccessData.class);
+        systemEventMappings.put(canonicalizeEventType(SystemEventTypes.RESOURCE_ACTION_FAILURE_EVENT), ResourceActionFailureData.class);
+        systemEventMappings.put(canonicalizeEventType(SystemEventTypes.RESOURCE_ACTION_CANCEL_EVENT), ResourceActionCancelData.class);
+        //
+        // ServiceBus events.
+        systemEventMappings.put(canonicalizeEventType(SystemEventTypes.SERVICE_BUS_ACTIVE_MESSAGES_AVAILABLE_WITH_NO_LISTENERS_EVENT), ServiceBusActiveMessagesAvailableWithNoListenersEventData.class);
+        systemEventMappings.put(canonicalizeEventType(SystemEventTypes.SERVICE_BUS_DEADLETTER_MESSAGES_AVAILABLE_WITH_NO_LISTENER_EVENT), ServiceBusDeadletterMessagesAvailableWithNoListenersEventData.class);
+        //
+        // Storage events.
+        systemEventMappings.put(canonicalizeEventType(SystemEventTypes.STORAGE_BLOB_CREATED_EVENT), StorageBlobCreatedEventData.class);
+        systemEventMappings.put(canonicalizeEventType(SystemEventTypes.STORAGE_BLOB_DELETED_EVENT), StorageBlobDeletedEventData.class);
+    }
+
+    /**
+     * Checks if a mapping exists for the given type.
+     *
+     * @param eventType the event type.
+     * @return true if mapping exists, false otherwise.
+     */
+    @Beta
+    public static boolean containsMappingFor(final String eventType) {
+        if (eventType == null || eventType.isEmpty()) {
+            return false;
+        } else {
+            return systemEventMappings.containsKey(canonicalizeEventType(eventType));
+        }
+    }
+
+    /**
+     * Get Java model type for the given event type.
+     *
+     * @param eventType the event type.
+     * @return the Java model type if mapping exists, null otherwise.
+     */
+    @Beta
+    public static Type getMapping(final String eventType) {
+        if (!containsMappingFor(eventType)) {
+            return null;
+        } else {
+            return systemEventMappings.get(canonicalizeEventType(eventType));
+        }
+    }
+
+    private static String canonicalizeEventType(final String eventType) {
+        if (eventType == null) {
+            return null;
+        } else {
+            return eventType.toLowerCase();
+        }
+    }
+}