ZEPPELIN-2990. Matplotlib sometimes fails in IPythonInterpreter

interpreter-parent/pom.xml

@@ -78,6 +78,14 @@
         <plugin>
           <artifactId>maven-dependency-plugin</artifactId>
           <executions>
+            <execution>
+              <id>copy-dependencies</id>
+              <phase>none</phase>
+              <configuration>
+                <skip>true</skip>
+              </configuration>
+            </execution>
+
             <execution>
               <id>copy-interpreter-dependencies</id>
               <phase>package</phase>

python/src/main/java/org/apache/zeppelin/python/IPythonClient.java

@@ -96,7 +96,7 @@ public void onNext(ExecuteResponse executeResponse) {
             LOGGER.debug("Interpreter Streaming Output: " + executeResponse.getOutput());
             if (isPreviousOutputImage) {
               // add '\n' when switch from image to text
-              interpreterOutput.write("\n".getBytes());
+              interpreterOutput.write("\n%text ".getBytes());
             }
             isPreviousOutputImage = false;
             interpreterOutput.write(executeResponse.getOutput().getBytes());

python/src/main/java/org/apache/zeppelin/python/IPythonInterpreter.java

@@ -286,6 +286,7 @@ protected Map<String, String> setupIPythonEnv() throws IOException {
     } else {
       envs.put("PYTHONPATH", additionalPythonPath);
     }
+    LOGGER.info("PYTHONPATH:" + envs.get("PYTHONPATH"));
     return envs;
   }
 

python/src/test/java/org/apache/zeppelin/python/IPythonInterpreterTest.java

@@ -284,12 +284,24 @@ public void run() {
     // the order of IMAGE and TEXT is not determined
     // check there must be one IMAGE output
     boolean hasImageOutput = false;
+    boolean hasLineText = false;
+    boolean hasFigureText = false;
     for (InterpreterResultMessage msg : interpreterResultMessages) {
       if (msg.getType() == InterpreterResult.Type.IMG) {
         hasImageOutput = true;
       }
+      if (msg.getType() == InterpreterResult.Type.TEXT
+          && msg.getData().contains("matplotlib.lines.Line2D")) {
+        hasLineText = true;
+      }
+      if (msg.getType() == InterpreterResult.Type.TEXT
+          && msg.getData().contains("matplotlib.figure.Figure")) {
+        hasFigureText = true;
+      }
     }
     assertTrue("No Image Output", hasImageOutput);
+    assertTrue("No Line Text", hasLineText);
+    assertTrue("No Figure Text", hasFigureText);
 
     // bokeh
     // bokeh initialization

spark/src/test/java/org/apache/zeppelin/spark/IPySparkInterpreterTest.java

@@ -146,7 +146,7 @@ public void run() {
         List<InterpreterResultMessage> interpreterResultMessages = null;
         try {
           interpreterResultMessages = context2.out.getInterpreterResultMessages();
-          assertTrue(interpreterResultMessages.get(0).getData().contains("cancelled"));
+          assertTrue(interpreterResultMessages.get(0).getData().contains("KeyboardInterrupt"));
         } catch (IOException e) {
           e.printStackTrace();
         }
@@ -180,7 +180,7 @@ public void run() {
         "ssc.start()\n" +
         "time.sleep(6)\n" +
         "ssc.stop(stopSparkContext=False, stopGraceFully=True)", context);
-    Thread.sleep(100);
+    Thread.sleep(1000);
     assertEquals(InterpreterResult.Code.SUCCESS, result.code());
     interpreterResultMessages = context.out.getInterpreterResultMessages();
     assertEquals(1, interpreterResultMessages.size());

zeppelin-server/src/main/java/org/apache/zeppelin/socket/NotebookServer.java

@@ -357,7 +357,7 @@ public void onMessage(NotebookSocket conn, String msg) {
           break;
       }
     } catch (Exception e) {
-      LOG.error("Can't handle message", e);
+      LOG.error("Can't handle message: " + msg, e);
     }
   }
 

zeppelin-zengine/src/main/java/org/apache/zeppelin/interpreter/remote/RemoteInterpreterEventPoller.java

@@ -246,7 +246,6 @@ public RemoteInterpreterEvent call(Client client) throws Exception {
             listener.onParaInfosReceived(noteId, paraId, settingId, paraInfos);
           }
         }
-        logger.debug("Event from remote process {}", event.getType());
       } catch (Exception e) {
         logger.error("Can't handle event " + event, e);
       }