cgivre commented on a change in pull request #1892: Drill-7437: Storage Plugin 
for Generic HTTP REST API
URL: https://github.com/apache/drill/pull/1892#discussion_r363142920
 
 

 ##########
 File path: 
contrib/storage-http/src/main/java/org/apache/drill/exec/store/http/util/SimpleHttp.java
 ##########
 @@ -0,0 +1,235 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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 org.apache.drill.exec.store.http.util;
+
+import okhttp3.Cache;
+import okhttp3.Credentials;
+import okhttp3.FormBody;
+import okhttp3.Interceptor;
+import okhttp3.OkHttpClient;
+import okhttp3.OkHttpClient.Builder;
+import okhttp3.Request;
+import okhttp3.Response;
+
+import org.apache.drill.common.exceptions.UserException;
+import org.apache.drill.exec.ExecConstants;
+import org.apache.drill.exec.ops.FragmentContext;
+import org.apache.drill.exec.store.http.HttpAPIConfig;
+import org.apache.drill.exec.store.http.HttpStoragePluginConfig;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.File;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.Map;
+import java.util.concurrent.TimeUnit;
+import java.util.regex.Pattern;
+
+
+/**
+ * This class performs the actual HTTP requests for the HTTP Storage Plugin. 
The core method is the getInputStream()
+ * method which accepts a url and opens an InputStream with that URL's 
contents.
+ */
+public class SimpleHttp {
+  private static final Logger logger = 
LoggerFactory.getLogger(SimpleHttp.class);
+
+  private final OkHttpClient client;
+
+  private final HttpStoragePluginConfig config;
+
+  private final FragmentContext context;
+
+  private final HttpAPIConfig apiConfig;
+
+  public SimpleHttp(HttpStoragePluginConfig config, FragmentContext context, 
String connectionName) {
+    this.config = config;
+    this.context = context;
+    this.apiConfig = config.connections().get(connectionName);
+    client = setupServer();
+  }
+
+
+
+  public InputStream getInputStream(String urlStr) {
+    Request.Builder requestBuilder;
+
+    // The configuration does not allow for any other request types other than 
POST and GET.
+    if (apiConfig.method().equals("get")) {
+      // Handle GET requests
+      requestBuilder = new Request.Builder().url(urlStr);
+    } else {
+      // Handle POST requests
+      FormBody.Builder formBodyBuilder = buildPostBody();
+      requestBuilder = new Request.Builder()
+        .url(urlStr)
+        .post(formBodyBuilder.build());
+    }
+
+    // Add headers to request
+    if (apiConfig.headers() != null) {
+      for (Map.Entry<String, String> entry : apiConfig.headers().entrySet()) {
+        String key = entry.getKey();
+        String value = entry.getValue();
+        requestBuilder.addHeader(key, value);
+      }
+    }
+
+    // Build the request object
+    Request request = requestBuilder.build();
+    logger.debug("Headers: {}", request.headers());
+
+    try {
+      // Execute the request
+      Response response = client
+        .newCall(request)
+        .execute();
+      logger.debug(response.toString());
+
+      // If the request is unsuccessful, throw a UserException
+      if (!response.isSuccessful()) {
+        throw UserException.dataReadError()
+          .message("Error retrieving data: " + response.code() + " " + 
response.message())
+          .addContext("Response code: ", response.code())
+          .build(logger);
+      }
+      logger.debug("HTTP Request for {} successful.", urlStr);
+      logger.debug("Response Headers: {} ", response.headers().toString());
+
+      // Return the InputStream of the response
+      return response.body().byteStream();
+    } catch (IOException e) {
+      throw UserException.functionError()
+        .message("Error retrieving data")
+        .addContext(e.getMessage())
+        .build(logger);
+    }
+  }
+
+  /**
+   * Function configures the OkHTTP3 server object with configuration info 
from the user.
+   *
+   * @return OkHttpClient configured server
+   */
+  private OkHttpClient setupServer() {
+    Builder builder = new OkHttpClient.Builder();
+
+    // Set up the HTTP Cache.   Future possibilities include making the cache 
size and retention configurable but
+    // right now it is on or off.  The writer will write to the Drill temp 
directory if it is accessible and
+    // output a warning if not.
+    if (config.cacheResults()) {
+      setupCache(builder);
+    }
+
+    // If the API uses basic authentication add the authentication code.
+    if (apiConfig.authType().toLowerCase().equals("basic")) {
+      logger.debug("Adding Interceptor");
+      builder.addInterceptor(new BasicAuthInterceptor(apiConfig.userName(), 
apiConfig.password()));
+    }
+
+    // Set timeout
+    builder.connectTimeout(config.timeout(), TimeUnit.SECONDS);
+    builder.writeTimeout(config.timeout(), TimeUnit.SECONDS);
+    builder.readTimeout(config.timeout(), TimeUnit.SECONDS);
+
+    return builder.build();
+  }
+
+  /**
+   * This function accepts a Builder object as input and configures response 
caching. In order for
+   * caching to work, the DRILL_TMP_DIR variable must be set either as a 
system environment variable or in the
+   * Drill configurations.
+   * <p>
+   * The function will attempt to get the DRILL_TMP_DIR from these places, and 
if it cannot, it will issue a warning in the logger.
+   *
+   * @param builder Builder the Builder object to which the cacheing is to be 
configured
+   */
+  private void setupCache(Builder builder) {
+    int cacheSize = 10 * 1024 * 1024;   // TODO Add cache size in MB to config
+    String drillTempDir;
+
+    try {
+      if (context.getOptions().getOption(ExecConstants.DRILL_TMP_DIR) != null) 
{
+        drillTempDir = 
context.getOptions().getOption(ExecConstants.DRILL_TMP_DIR).string_val;
+      } else {
+        drillTempDir = System.getenv("DRILL_TMP_DIR");
+      }
+      File cacheDirectory = new File(drillTempDir);
+      if (cacheDirectory == null) {
+        logger.warn("HTTP Storage plugin caching requires the DRILL_TMP_DIR to 
be configured. Please either set DRILL_TMP_DIR or disable HTTP caching.");
 
 Review comment:
   The idea here was that responses could be cached in the event that it was 
making the same HTTP request over and over.  This can be disabled in the 
config. 

----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
 
For queries about this service, please contact Infrastructure at:
us...@infra.apache.org


With regards,
Apache Git Services

Reply via email to