Merge pull request #34 from AlejandroRivera/feature/disable-embedded-…

…server

Added the option to disable the embedded HTTP server.

README.md

@@ -58,10 +58,13 @@ packageWhitelist | Colon-delimited whitelist for packages to include (optional,
 packageBlacklist | Colon-delimited whitelist for packages to exclude (optional, defaults to exclude nothing)
 profilers        | Colon-delimited list of profiler class names (optional, defaults to CPUProfiler and MemoryProfiler)
 reporter         | Class name of the reporter to use (optional, defaults to StatsDReporter)
+httpServerEnabled| Determines if the embedded HTTP server should be started. (optional, defaults to `true`)
 httpPort         | The port on which to bind the embedded HTTP server (optional, defaults to 5005). If this port is already in use, the next free port will be taken.
 
 ### Embedded HTTP Server
-statsd-jvm-profiler embeds an HTTP server to support simple interactions with the profiler while it is in operation.  You can configure the port on which this server runs with the `httpPort` option.
+statsd-jvm-profiler embeds an HTTP server to support simple interactions with the profiler while it is in operation.
+You can configure the port on which this server runs with the `httpPort` option.
+You can disable it altogether using the `httpServerEnabled=false` argument.
 
 Endpoint                    | Usage
 ---------------             | -----

src/main/java/com/etsy/statsd/profiler/Agent.java

@@ -50,16 +50,17 @@ public static void premain(final String args, final Instrumentation instrumentat
             profilers.add(instantiate(profiler, Profiler.CONSTRUCTOR_PARAM_TYPES, reporter, arguments));
         }
 
-        scheduleProfilers(profilers, arguments.httpPort);
+        scheduleProfilers(profilers, arguments);
         registerShutdownHook(profilers);
     }
 
     /**
      * Schedule profilers with a SchedulerExecutorService
      *
      * @param profilers Collection of profilers to schedule
+     * @param arguments
      */
-    private static void scheduleProfilers(Collection<Profiler> profilers, int httpPort) {
+    private static void scheduleProfilers(Collection<Profiler> profilers, Arguments arguments) {
         // We need to convert to an ExitingScheduledExecutorService so the JVM shuts down
         // when the main thread finishes
         ScheduledExecutorService scheduledExecutorService = MoreExecutors.getExitingScheduledExecutorService(
@@ -73,7 +74,10 @@ private static void scheduleProfilers(Collection<Profiler> profilers, int httpPo
             ScheduledFuture future =  scheduledExecutorService.scheduleAtFixedRate(worker, EXECUTOR_DELAY, profiler.getPeriod(), profiler.getTimeUnit());
             runningProfilers.put(profiler.getClass().getSimpleName(), future);
         }
-        ProfilerServer.startServer(runningProfilers, activeProfilers, httpPort, isRunning, errors);
+
+        if (arguments.httpServerEnabled) {
+            ProfilerServer.startServer(runningProfilers, activeProfilers, arguments.httpPort, isRunning, errors);
+        }
     }
 
     /**

src/main/java/com/etsy/statsd/profiler/Arguments.java

@@ -20,6 +20,7 @@ public class Arguments {
     private static final String PROFILERS = "profilers";
     private static final String REPORTER = "reporter";
     private static final String HTTP_PORT = "httpPort";
+    private static final String HTTP_SEVER_ENABLED = "httpServerEnabled";
 
     private static final Collection<String> REQUIRED = Arrays.asList(SERVER, PORT);
 
@@ -56,6 +57,7 @@ public static Arguments parseArgs(final String args) {
     public Map<String, String> remainingArgs;
     public Class<? extends Reporter<?>> reporter;
     public int httpPort;
+    public boolean httpServerEnabled;
 
     private Arguments(Map<String, String> parsedArgs) {
         server = parsedArgs.get(SERVER);
@@ -64,6 +66,7 @@ private Arguments(Map<String, String> parsedArgs) {
         profilers = parseProfilerArg(parsedArgs.get(PROFILERS));
         reporter = parserReporterArg(parsedArgs.get(REPORTER));
         httpPort = Integer.parseInt(Optional.fromNullable(parsedArgs.get(HTTP_PORT)).or("5005"));
+        httpServerEnabled = Boolean.parseBoolean(Optional.fromNullable(parsedArgs.get(HTTP_SEVER_ENABLED)).or("true"));
 
         parsedArgs.remove(SERVER);
         parsedArgs.remove(PORT);
@@ -112,7 +115,7 @@ private Set<Class<? extends Profiler>> parseProfilerArg(String profilerArg) {
         }
 
         if (parsedProfilers.isEmpty()) {
-            throw new IllegalArgumentException("At least one profiler must be run");
+            throw new IllegalArgumentException("At least one profiler must be specified");
         }
 
         return parsedProfilers;

src/test/java/com/etsy/statsd/profiler/ArgumentsTest.java

@@ -12,6 +12,8 @@
 import java.util.Set;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
 
 public class ArgumentsTest {
     @Rule
@@ -144,4 +146,20 @@ public void testDefaultReporter() {
 
         assertEquals(StatsDReporter.class, arguments.reporter);
     }
+
+    @Test
+    public void testHttpServerEnabledByDefault() throws Exception {
+        String args = "server=localhost,port=8125";
+        Arguments arguments = Arguments.parseArgs(args);
+
+        assertTrue(arguments.httpServerEnabled);
+    }
+
+    @Test
+    public void testHttpServerDisabled() throws Exception {
+        String args = "server=localhost,port=8125,httpServerEnabled=false";
+        Arguments arguments = Arguments.parseArgs(args);
+
+        assertFalse(arguments.httpServerEnabled);
+    }
 }