sqoop-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Veena Basavaraj (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (SQOOP-1784) Sqoop2: Sending POST request to link or job end-point might end up with NPE
Date Sun, 23 Nov 2014 23:27:12 GMT

    [ https://issues.apache.org/jira/browse/SQOOP-1784?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14222537#comment-14222537

Veena Basavaraj commented on SQOOP-1784:

Lastly thinking more about the actual patch. here are few things that should be addressed.

The code at the least should have some comments saying why this order matters.

This might bite us again, it might take forever for a developer to realize that changing the
order of the statements has implications that are not obvious. There may other params added
in future and making sure they are read in the right order is not always obvious

Alternatively, some defensive coding might be good.

Second, we can have a wrapper HttpServletRequestWrapper that forces how we do getParameter.


> Sqoop2: Sending POST request to link or job end-point might end up with NPE
> ---------------------------------------------------------------------------
>                 Key: SQOOP-1784
>                 URL: https://issues.apache.org/jira/browse/SQOOP-1784
>             Project: Sqoop
>          Issue Type: Bug
>    Affects Versions: 1.99.4
>            Reporter: Jarek Jarcec Cecho
>            Assignee: Jarek Jarcec Cecho
>             Fix For: 1.99.5
>         Attachments: SQOOP-1784.patch
> I was testing few patches on real cluster and noticed that creating link on current head
of {{sqoop2}} branch can lead to NPE in {{LinkBean}}. I've traced the code and found out that
is returning empty buffer and as a result the subsequent call to {{JSONValue.parse}} returns
{{null}} and we hit {{NullPointerException}} later in {{LInkBean}}.
> This one was quite hard to crack, but I believe that I've isolated the problem. In SQOOP-1774
we've changed the way to get username from header to URL parameter and we're using {{[ServletRequest.getParameter()|https://github.com/apache/sqoop/blob/sqoop2/server/src/main/java/org/apache/sqoop/server/RequestContext.java#L121]}}
method for that. Carefully reading it's [javadoc|https://docs.oracle.com/javaee/6/api/javax/servlet/ServletRequest.html#getParameter(java.lang.String)]
I found out that:
> {quote}
> If the parameter data was sent in the request body, such as occurs with an HTTP POST
request, then reading the body directly via getInputStream() or getReader() can interfere
with the execution of this method
> {quote}
> And hence I'm assuming that getting the username has processed the request body already
and thus we got the eventual {{NullPointerException}}.

This message was sent by Atlassian JIRA

View raw message