[ZEPPELIN-2758]. NumberFormatException on importing notebook

[zjffdu]

What is this PR for?

This is due to the custom TypeAdapter for Paragraph. I don't know why we introduce it. To me it is not necessary. So I remove this in this PR. And the spark UI still can be accessed in frontend.

What type of PR is it?

[Bug Fix]

Todos

• - Task

What is the Jira issue?

• https://issues.apache.org/jira/browse/ZEPPELIN-2758

How should this be tested?

Unit test is updated and manually tested

Screenshots (if appropriate)

Questions:

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

[zjffdu]

@karuppayya I remove NotebookTypeAdapterFactory.java which I think is not necessary. Let me know your concern.

[necosta]

LGTM

[zjffdu]

Will merge it if no more comments.

[karuppayya]

@zjffdu the NotebookTypeAdapterFactory was added to avoid runtimeInfos being persisted in json. (These infos are valid only during the runtime of the Zeppelin server, interpreter)
How are we handling this now?

[zjffdu]

Thanks @karuppayya So do you mean Note will be serialized to different formats for runtime serialized to frontend and serialized to file ? What is the side effect if I store it in file ?

[karuppayya]

Currently only the frontend receives this info.
If we remove the AdapterFactory, The runtimeInfos will be serialised to json file.
Say runtimeinfos contain spark UI link.
if it is persisted in json, when Zeppelin server restarts, we will see a invalid spark UI link(we can clean the runtimeinfos during zep server initialization though), which we might not want

[zjffdu]

Thanks @karuppayya for explaining. How about reset the runtimeInfos to null when deserialized from json (it happens when it is read from file). Serializing to different formats in different scenarios seems a little complicated to me

[karuppayya]

Yeah , we can reset the infos when the json is deserialized.

[zjffdu]

Thanks @karuppayya push another commit to reset the runtimeInfo when deseriliazed from json.

[zjffdu]

Will merge it if no more comments.

[prabhjyotsingh]

LGTM!