WebService refactoring (#40)

* Little WebService refactor, removing magic values, removing unnecessary argument in the constructor.

pulsar-broker/src/main/java/com/yahoo/pulsar/broker/PulsarService.java

@@ -246,7 +246,7 @@ public class PulsarService implements AutoCloseable {
             LOG.info("Starting Pulsar Broker service");
             brokerService.start();
 
-            this.webService = new WebService(config, this);
+            this.webService = new WebService(this);
             this.webService.addRestResources("/", "com.yahoo.pulsar.broker.web", false);
             this.webService.addRestResources("/admin", "com.yahoo.pulsar.broker.admin", true);
             this.webService.addRestResources("/lookup", "com.yahoo.pulsar.broker.lookup", true);

pulsar-broker/src/main/java/com/yahoo/pulsar/broker/web/PulsarWebResource.java

@@ -73,7 +73,7 @@ public abstract class PulsarWebResource {
 
     protected PulsarService pulsar() {
         if (pulsar == null) {
-            pulsar = (PulsarService) servletContext.getAttribute("pulsar");
+            pulsar = (PulsarService) servletContext.getAttribute(WebService.ATTRIBUTE_PULSAR_NAME);
         }
 
         return pulsar;

pulsar-broker/src/main/java/com/yahoo/pulsar/broker/web/WebService.java

@@ -53,7 +53,6 @@ import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Lists;
 import com.yahoo.pulsar.broker.PulsarServerException;
 import com.yahoo.pulsar.broker.PulsarService;
-import com.yahoo.pulsar.broker.ServiceConfiguration;
 import com.yahoo.pulsar.common.util.ObjectMapperFactory;
 import com.yahoo.pulsar.common.util.SecurityUtility;
 
@@ -63,52 +62,61 @@ import io.netty.util.concurrent.DefaultThreadFactory;
  * Web Service embedded into Pulsar
  */
 public class WebService implements AutoCloseable {
-    private final ServiceConfiguration config;
-    private final PulsarService pulsar;
-    private final Server server;
-    private final List<Handler> handlers = Lists.newArrayList();
-    private final ExecutorService webServiceExecutor;
 
     /**
      * The set of path regexes on which the ApiVersionFilter is installed if needed
      */
-    private static final List<Pattern> API_VERSION_FILTER_PATTERNS = ImmutableList.of(Pattern.compile("^/lookup.*") // V2
-                                                                                                                    // lookups
+    private static final List<Pattern> API_VERSION_FILTER_PATTERNS = ImmutableList.of(
+            Pattern.compile("^/lookup.*") // V2 lookups
     );
+    private static final String MATCH_ALL = "/*";
+
+    public static final String ATTRIBUTE_PULSAR_NAME = "pulsar";
+    public static final String HANDLER_CACHE_CONTROL = "max-age=3600";
+    public static final String HANDLER_REQUEST_LOG_TZ = "GMT";
+    public static final int NUM_ACCEPTORS = 32; // make it configurable?
+    public static final int MAX_CONCURRENT_REQUESTES = 1024; // make it configurable?
+
+    private final PulsarService pulsar;
+    private final Server server;
+    private final List<Handler> handlers;
+    private final ExecutorService webServiceExecutor;
 
-    public WebService(ServiceConfiguration config, PulsarService pulsar) throws PulsarServerException {
-        this.config = config;
+    public WebService(PulsarService pulsar) throws PulsarServerException {
+        this.handlers = Lists.newArrayList();
         this.pulsar = pulsar;
-        this.webServiceExecutor = Executors.newFixedThreadPool(32, new DefaultThreadFactory("pulsar-web"));
+        this.webServiceExecutor = Executors.newFixedThreadPool(WebService.NUM_ACCEPTORS, new DefaultThreadFactory("pulsar-web"));
         this.server = new Server(new ExecutorThreadPool(webServiceExecutor));
         List<ServerConnector> connectors = new ArrayList<>();
 
         ServerConnector connector = new PulsarServerConnector(server, 1, 1);
-        connector.setPort(config.getWebServicePort());
+        connector.setPort(pulsar.getConfiguration().getWebServicePort());
         connector.setHost(pulsar.getBindAddress());
         connectors.add(connector);
 
-        if (config.isTlsEnabled()) {
+        if (pulsar.getConfiguration().isTlsEnabled()) {
             SslContextFactory sslCtxFactory = new SslContextFactory();
 
             try {
-                SSLContext sslCtx = SecurityUtility.createSslContext(config.isTlsAllowInsecureConnection(),
-                        config.getTlsTrustCertsFilePath(), config.getTlsCertificateFilePath(),
-                        config.getTlsKeyFilePath());
-                sslCtxFactory.setSslContext(sslCtx);
+                sslCtxFactory.setSslContext(
+                        SecurityUtility.createSslContext(
+                            pulsar.getConfiguration().isTlsAllowInsecureConnection(),
+                            pulsar.getConfiguration().getTlsTrustCertsFilePath(),
+                            pulsar.getConfiguration().getTlsCertificateFilePath(),
+                            pulsar.getConfiguration().getTlsKeyFilePath()));
             } catch (GeneralSecurityException e) {
                 throw new PulsarServerException(e);
             }
 
             sslCtxFactory.setWantClientAuth(true);
             ServerConnector tlsConnector = new PulsarServerConnector(server, 1, 1, sslCtxFactory);
-            tlsConnector.setPort(config.getWebServicePortTls());
+            tlsConnector.setPort(pulsar.getConfiguration().getWebServicePortTls());
             tlsConnector.setHost(pulsar.getBindAddress());
             connectors.add(tlsConnector);
         }
 
         // Limit number of concurrent HTTP connections to avoid getting out of file descriptors
-        connectors.stream().forEach(c -> c.setAcceptQueueSize(1024 / connectors.size()));
+        connectors.forEach(c -> c.setAcceptQueueSize(WebService.MAX_CONCURRENT_REQUESTES / connectors.size()));
         server.setConnectors(connectors.toArray(new ServerConnector[connectors.size()]));
     }
 
@@ -125,23 +133,23 @@ public class WebService implements AutoCloseable {
     public void addServlet(String path, ServletHolder servletHolder, boolean requiresAuthentication) {
         ServletContextHandler context = new ServletContextHandler(ServletContextHandler.SESSIONS);
         context.setContextPath(path);
-        context.addServlet(servletHolder, "/*");
-        context.setAttribute("pulsar", pulsar);
-        context.setAttribute("config", config);
+        context.addServlet(servletHolder, MATCH_ALL);
+        context.setAttribute(WebService.ATTRIBUTE_PULSAR_NAME, pulsar);
 
-        if (requiresAuthentication && config.isAuthenticationEnabled()) {
+        if (requiresAuthentication && pulsar.getConfiguration().isAuthenticationEnabled()) {
             FilterHolder filter = new FilterHolder(new AuthenticationFilter(pulsar));
-            context.addFilter(filter, "/*", EnumSet.allOf(DispatcherType.class));
+            context.addFilter(filter, MATCH_ALL, EnumSet.allOf(DispatcherType.class));
         }
 
         log.info("Servlet path: '{}' -- Enable client version check: {} -- shouldCheckApiVersionOnPath: {}", path,
-                config.isClientLibraryVersionCheckEnabled(), shouldCheckApiVersionOnPath(path));
-        if (config.isClientLibraryVersionCheckEnabled() && shouldCheckApiVersionOnPath(path)) {
+                pulsar.getConfiguration().isClientLibraryVersionCheckEnabled(),
+                shouldCheckApiVersionOnPath(path));
+        if (pulsar.getConfiguration().isClientLibraryVersionCheckEnabled() && shouldCheckApiVersionOnPath(path)) {
             // Add the ApiVersionFilter to reject request from deprecated
             // clients.
             FilterHolder holder = new FilterHolder(
-                    new ApiVersionFilter(pulsar, config.isClientLibraryVersionCheckAllowUnversioned()));
-            context.addFilter(holder, "/*", EnumSet.allOf(DispatcherType.class));
+                    new ApiVersionFilter(pulsar, pulsar.getConfiguration().isClientLibraryVersionCheckAllowUnversioned()));
+            context.addFilter(holder, MATCH_ALL, EnumSet.allOf(DispatcherType.class));
             log.info("Enabling ApiVersionFilter");
         }
 
@@ -154,7 +162,7 @@ public class WebService implements AutoCloseable {
         ResourceHandler resHandler = new ResourceHandler();
         resHandler.setBaseResource(Resource.newClassPathResource(resourcePath));
         resHandler.setEtags(true);
-        resHandler.setCacheControl("max-age=3600");
+        resHandler.setCacheControl(WebService.HANDLER_CACHE_CONTROL);
         capHandler.setHandler(resHandler);
         handlers.add(capHandler);
     }
@@ -181,7 +189,7 @@ public class WebService implements AutoCloseable {
             RequestLogHandler requestLogHandler = new RequestLogHandler();
             Slf4jRequestLog requestLog = new Slf4jRequestLog();
             requestLog.setExtended(true);
-            requestLog.setLogTimeZone("GMT");
+            requestLog.setLogTimeZone(WebService.HANDLER_REQUEST_LOG_TZ);
             requestLog.setLogLatency(true);
             requestLogHandler.setRequestLog(requestLog);
             handlers.add(0, new ContextHandlerCollection());