com.seleritycorp.common.base.eventprocessor.EventSender.java Source code

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Here is the source code for com.seleritycorp.common.base.eventprocessor.EventSender.java

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/*
 * Copyright (C) 2016-2018 Selerity, Inc. (support@seleritycorp.com)
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.seleritycorp.common.base.eventprocessor;

import com.google.gson.JsonObject;

import com.seleritycorp.common.base.config.ApplicationConfig;
import com.seleritycorp.common.base.config.Config;
import com.seleritycorp.common.base.http.client.HttpException;
import com.seleritycorp.common.base.http.client.HttpRequestFactory;
import com.seleritycorp.common.base.logging.Log;
import com.seleritycorp.common.base.logging.LogFactory;
import com.seleritycorp.common.base.uuid.UuidGenerator;

import org.apache.http.HttpStatus;

import java.util.UUID;

import javax.inject.Inject;

/**
 * Helper to send Events to Event Processor.
 */
public class EventSender {
    private static final Log log = LogFactory.getLog(EventSender.class);

    private final UuidGenerator uuidGenerator;
    private final String targetUrl;
    private final HttpRequestFactory requestFactory;

    /**
     * Creates a Sender for EventProcessing events.
     * 
     * @param config The application config to use.
     * @param uuidGenerator Used for request ids.
     * @param requestFactory Factory for Http requests.
     */
    @Inject
    public EventSender(@ApplicationConfig Config config, UuidGenerator uuidGenerator,
            HttpRequestFactory requestFactory) {
        this.uuidGenerator = uuidGenerator;
        this.targetUrl = config.get("EventProcessor.beaconUrl", "https://event.seleritycorp.com/beacon");
        this.requestFactory = requestFactory;
    }

    /**
     * Send an Event to EventProcessor while ignoring eventual issues.
     *
     * <p>If there are issues with sending, they'll be logged, but they won't be escalated to the
     * caller.
     *
     * <p>Use this method for fire-and-forget events. If you want to check that atleast that the
     * Http aspect of sending worked, see {@link #sendChecked(String, int, JsonObject)} instead.
     *
     * @param schema The name of the schema to send an event for
     * @param schemaVersion The version number for the schema
     * @param payload The payload to send.
     * @return The UUID of the sent event.
     */
    public UUID send(String schema, int schemaVersion, JsonObject payload) {
        UUID uuid = uuidGenerator.generate();
        try {
            sendChecked(uuid, schema, schemaVersion, payload);
        } catch (Exception e) {
            log.info("Failed to send beacon for " + schema + " (version " + schemaVersion + ") to " + targetUrl, e);
        }
        return uuid;
    }

    /**
     * Send an Event to EventProcessor and escalates errors to the caller.
     *
     * <p>If no exceptions get thrown, this does not mean that the sent event passed validation.
     * It only means that on the HTTP layer everything worked. Event Processor is responding
     * before event validation takes place. So you need to check on the Event Processor side to
     * see if validation passes.
     *
     * <p>A fire-and-forget variant of sending events can be found at
     * {@link #send(String, int, JsonObject)}.
     *   
     * @param schema The name of the schema to send an event for
     * @param schemaVersion The version number for the schema
     * @param payload The payload to send.
     * @return The UUID of the sent event.
     * @throws HttpException if there are errors sending the request.
     */
    public UUID sendChecked(String schema, int schemaVersion, JsonObject payload) throws HttpException {
        UUID uuid = uuidGenerator.generate();
        sendChecked(uuid, schema, schemaVersion, payload);
        return uuid;
    }

    /**
     * Send an Event to EventProcessor and escalates errors to the caller.
     *
     * <p>If no exceptions get thrown, this does not mean that the sent event passed validation.
     * It only means that on the HTTP layer everything worked. Event Processor is responding
     * before event validation takes place. So you need to check on the Event Processor side to
     * see if validation passes.
     *   
     * @param schema The name of the schema to send an event for
     * @param schemaVersion The version number for the schema
     * @param payload The payload to send.
     * @throws HttpException if there are errors sending the request.
     */
    private void sendChecked(UUID uuid, String schema, int schemaVersion, JsonObject payload) throws HttpException {
        JsonObject data = new JsonObject();
        data.addProperty("schema", schema);
        data.addProperty("schemaVersion", schemaVersion);
        data.addProperty("uuid", uuid.toString());
        data.add("payload", payload);
        requestFactory.createPostJson(targetUrl, data).setExpectedStatusCode(HttpStatus.SC_NO_CONTENT).execute();
    }
}