Zeppelin 337 configurable context path (2)

[echarles]

Allow to configure the context path of the webapp via zeppelin.server.context.path property or ZEPPELIN_SERVER_CONTEXT_PATH env variable + documentation for this.

(replaces #385)

[echarles]

Travis fails with
09:59:03,926 INFO org.apache.zeppelin.rest.AbstractTestRestApi:247 - Connecting to http://localhost:8080/api/
09:59:03,929 INFO org.apache.zeppelin.rest.AbstractTestRestApi:252 - 404 - Not Found

On my laptop, mvn clean package -DskipTests -Phadoop-2.3 -Ppyspark -B on this branch runs successfully.

[jongyoul]

@echarles Your command passes the tests so you can build this but AbstractTestRestApi fails because that doesn't fix https://github.com/apache/incubator-zeppelin/blob/0a82a93ce495cf537b28104a024a8c0361fd80ac/zeppelin-server/src/test/java/org/apache/zeppelin/rest/AbstractTestRestApi.java#L52, too. And I have a basic question. Why do you need this feature as I commented https://issues.apache.org/jira/browse/ZEPPELIN-337.

[echarles]

@jongyoul just pushed an update and check is now successful.

It is common practice to define the context path in any webapp. Sometimes you don't have a proxy (nginx...) in front and still you want to deploy and answer requests on a defined url base.

[jongyoul]

@echarles Thanks for fixing it. Concerning use case, not using nginx, I don't think it's possible to serve saperate Zeppelin instance with, for example, http://some-domain/zeppelin_user1 and http://some-domain/zeppelin_user2 because each Zeppelin has a different port for listening to. Url based deployments is a proper solution for multi user but do you have to launch two Zeppelin instance with two different ports without Nginx? I think only it's possible to serve http://some-domain:port1/zeppelin_user1 and http://some-domain:port2/zeppelin_user2 - actually, zeppelin_user2 is not a mandatory. Without regard to this issue, I'm curious to serve two Zeppelin instance with same port without Nginx. Could you please share your case?

[echarles]

@jongyoul my intent here is not directly linked to serving different user. I just need to have zeppelin respond to a well defined context path.

[Leemoonsoo]

@jongyoul Is it good to go?

[jongyoul]

@Leemoonsoo Sure. Ready to merge.

[Leemoonsoo]

I have tested it and it working well.
However, when i create package using -Pbuild-distr maven profile, it does not work correctly.

@echarles Could you take a look?

[jongyoul]

Oops. I'll check it, too.

[echarles]

@jongyoul @Leemoonsoo Thank you for reviewing this and pointing remaining issues.

I have fixed the behavior in the distribution package (simply calling the setContextPath before the check warPath.isDirectory()) and pushed 37e07f9. It now works in IDE, simple repo and distibution modes.

Travis build is happy. Can please you recheck and send any feedback?

[Leemoonsoo]

Tested and working nicely both with/without -Pbuild-distr

LGTM

[Leemoonsoo]

Merge if there're no more discussions.