BigqueryInjectionConfiguration.java

/*
 * This file is a component of thundr, a software library from 3wks.
 * Read more: http://www.3wks.com.au/thundr
 * Copyright (C) 2013 3wks, <thundr@3wks.com.au>
 *
 * 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.threewks.thundr.bigquery;

import java.io.File;

import com.google.api.client.googleapis.auth.oauth2.GoogleCredential;
import com.google.api.client.http.javanet.NetHttpTransport;
import com.google.api.client.json.gson.GsonFactory;
import com.google.api.services.bigquery.Bigquery;
import com.threewks.thundr.injection.InjectionConfiguration;
import com.threewks.thundr.injection.InjectionException;
import com.threewks.thundr.injection.UpdatableInjectionContext;
import com.threewks.thundr.logger.Logger;

public class BigqueryInjectionConfiguration implements InjectionConfiguration {
	@Override
	public void configure(UpdatableInjectionContext injectionContext) {

		GoogleCredential credential = buildBigQueryGoogleCredential(injectionContext);
		injectionContext.inject(credential).as(GoogleCredential.class);
		injectionContext.inject(buildBigQuery(credential)).as(Bigquery.class);

		Logger.info("Loaded BigQuery module");
	}

	/**
	 * Build a {@link GoogleCredential} for accessing Google APIs (eg: BigQuery).
	 */
	private GoogleCredential buildBigQueryGoogleCredential(UpdatableInjectionContext injectionContext) {

		String certificate = injectionContext.get(String.class, "googleApiCertificate");
		String accountId = injectionContext.get(String.class, "googleApiAccountId");
		String clientId = injectionContext.get(String.class, "googleApiClientId");
		String clientSecret = injectionContext.get(String.class, "googleApiClientSecret");

		try {
			File privateKey = new File(getClass().getResource(certificate).toURI());
			GoogleCredential.Builder builder = new GoogleCredential.Builder();
			builder.setTransport(new NetHttpTransport());
			builder.setServiceAccountId(accountId);
			builder.setJsonFactory(new GsonFactory());
			builder.setClientSecrets(clientId, clientSecret);
			builder.setServiceAccountScopes("https://www.googleapis.com/auth/bigquery");
			builder.setServiceAccountPrivateKeyFromP12File(privateKey);
			return builder.build();
		} catch (Exception e) {
			throw new InjectionException(e, "Error creating BigQuery Google credential: %s", e.getMessage());
		}
	}

	/**
	 * Build a {@link Bigquery} object for accessing the BigQuery API.
	 */
	private Bigquery buildBigQuery(GoogleCredential googleCredential) {
		return new Bigquery.Builder(new NetHttpTransport(), new GsonFactory(), googleCredential).setApplicationName("thundr-bigquery/1.0").build();
	}
}