[ZEPPELIN-3928] Fix bugs AngularBind operation NullPointerException

[xunliu]

What is this PR for?

In the case where the note does not start the interpreter process, Direct use of the z.angularBind operation will have a null pointer exception.

What type of PR is it?

[Bug Fix]

Todos

• Fix the condition for judging the interpreter process when the note is used for angularBind.

What is the Jira issue?

• https://issues.apache.org/jira/browse/ZEPPELIN-3928

What Test

Create a new paragraph to display angularBind variables

%angular
<h2>this : {{COMMAND_TYPE}}</h2>

Create a new paragraph to bind variables

<form class="form-inline">
  <div class="form-group">
    <label for="superheroId">Super Hero: </label>
    <input type="text" class="form-control" id="superheroId" placeholder="Superhero name ..." ng-model="superhero"></input>
  </div>
  <button type="submit" class="btn btn-primary" ng-click="z.angularBind('COMMAND_TYPE',superhero,'paragraph_1545881601069_1553190230');"> Bind</button>
</form>

How should this be tested?

CI pass

Screenshots (if appropriate)

Before fixing BUG

After fixing the bug

Questions:

• Does the licenses files need update? No
• Is there breaking changes for older versions? No
• Does this needs documentation? No

[felixcheung]

thanks for all the details in the description.

it looks like there are two separate fixes here? what's the condition to reach object.getNoteId() == null?

[xunliu]

Judge object.getNoteId() == null Is to prevent Note note = getNotebook().getNote(object.getNoteId()); exception

[felixcheung]

I'm actually not sure why it wasn't doing getNotebook().getNote(note id) before @jongyoul @zjffdu ?

[xunliu]

object.getNoteId() == null, Can also not add this code, Just to be safer, Or do I cancel this judgment code?

[xunliu]

@felixcheung , @jongyoul , @zjffdu, Please help me review code. Thanks! :-)

[xunliu]

@felixcheung , I revert Optimize the execution efficiency of the NotebookServer::onUpdate(...) function. And CI Pass https://travis-ci.org/liuxunorg/zeppelin/builds/475618439

[zjffdu]

+1, Will merge if no more comments Thanks @liuxunorg