diff --git a/hadoop-common-project/hadoop-common/CHANGES.txt b/hadoop-common-project/hadoop-common/CHANGES.txt index df0585cff7e..3df1039730d 100644 --- a/hadoop-common-project/hadoop-common/CHANGES.txt +++ b/hadoop-common-project/hadoop-common/CHANGES.txt @@ -320,6 +320,9 @@ Release 2.0.3-alpha - Unreleased HADOOP-8929. Add toString, other improvements for SampleQuantiles (todd) + HADOOP-8922. Provide alternate JSONP output for JMXJsonServlet to allow + javascript in browser dashboard (Damien Hardy via bobby) + OPTIMIZATIONS HADOOP-8866. SampleQuantiles#query is O(N^2) instead of O(N). (Andrew Wang diff --git a/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/jmx/JMXJsonServlet.java b/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/jmx/JMXJsonServlet.java index 84dc15c882f..076ffb4c231 100644 --- a/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/jmx/JMXJsonServlet.java +++ b/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/jmx/JMXJsonServlet.java @@ -113,12 +113,17 @@ import org.codehaus.jackson.JsonGenerator; * All other objects will be converted to a string and output as such. * * The bean's name and modelerType will be returned for all beans. + * + * Optional paramater "callback" should be used to deliver JSONP response. + * */ public class JMXJsonServlet extends HttpServlet { private static final Log LOG = LogFactory.getLog(JMXJsonServlet.class); private static final long serialVersionUID = 1L; + private static final String CALLBACK_PARAM = "callback"; + /** * MBean server. */ @@ -154,11 +159,22 @@ public class JMXJsonServlet extends HttpServlet { return; } JsonGenerator jg = null; + String jsonpcb = null; + PrintWriter writer = null; try { - response.setContentType("application/json; charset=utf8"); + writer = response.getWriter(); + + // "callback" parameter implies JSONP outpout + jsonpcb = request.getParameter(CALLBACK_PARAM); + if (jsonpcb != null) { + response.setContentType("application/javascript; charset=utf8"); + writer.write(jsonpcb + "("); + } else { + response.setContentType("application/json; charset=utf8"); + } - PrintWriter writer = response.getWriter(); jg = jsonFactory.createJsonGenerator(writer); + jg.disable(JsonGenerator.Feature.AUTO_CLOSE_TARGET); jg.useDefaultPrettyPrinter(); jg.writeStartObject(); @@ -188,6 +204,12 @@ public class JMXJsonServlet extends HttpServlet { if (jg != null) { jg.close(); } + if (jsonpcb != null) { + writer.write(");"); + } + if (writer != null) { + writer.close(); + } } } catch (IOException e) { LOG.error("Caught an exception while processing JMX request", e); diff --git a/hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/jmx/TestJMXJsonServlet.java b/hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/jmx/TestJMXJsonServlet.java index ea2f76bf10a..41303f41d91 100644 --- a/hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/jmx/TestJMXJsonServlet.java +++ b/hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/jmx/TestJMXJsonServlet.java @@ -78,5 +78,29 @@ public class TestJMXJsonServlet extends HttpServerFunctionalTest { "/jmx?get=java.lang:type=Memory::")); LOG.info("/jmx RESULT: "+result); assertReFind("\"ERROR\"", result); + + // test to get JSONP result + result = readOutput(new URL(baseUrl, "/jmx?qry=java.lang:type=Memory&callback=mycallback1")); + LOG.info("/jmx?qry=java.lang:type=Memory&callback=mycallback RESULT: "+result); + assertReFind("^mycallback1\\(\\{", result); + assertReFind("\\}\\);$", result); + + // negative test to get an attribute of a mbean as JSONP + result = readOutput(new URL(baseUrl, + "/jmx?get=java.lang:type=Memory::&callback=mycallback2")); + LOG.info("/jmx RESULT: "+result); + assertReFind("^mycallback2\\(\\{", result); + assertReFind("\"ERROR\"", result); + assertReFind("\\}\\);$", result); + + // test to get an attribute of a mbean as JSONP + result = readOutput(new URL(baseUrl, + "/jmx?get=java.lang:type=Memory::HeapMemoryUsage&callback=mycallback3")); + LOG.info("/jmx RESULT: "+result); + assertReFind("^mycallback3\\(\\{", result); + assertReFind("\"name\"\\s*:\\s*\"java.lang:type=Memory\"", result); + assertReFind("\"committed\"\\s*:", result); + assertReFind("\\}\\);$", result); + } }