Add Oracle XE database container support

[swissarmykirpan]

Created an Oracle Container and simple test

[rnorth]

Thanks Gurpreet! Great work!

Technically it looks good to me, though I've not been able to run it yet (OJDBC dependency issues..)

I'd just like to think through a couple of issues associated with the difficulty of obtaining proprietary Oracle assets for testing and actual use:

• The OJDBC JAR can't be bundled, and it looks like Oracle's new maven repository needs registration. We can probably sort this out fairly easily for testing though (and we don't have a compile time/direct dependency on any drivers, deliberately)
• I want to understand the licence situation of the docker Oracle XE image. I've been thinking about making it possible to specify a full docker image name in the JDBC URL and/or custom docker registries, and these might be necessary to allow teams to use their own privately managed images.

Let's talk about these some time.

[swissarmykirpan]

I've pulled in your override commit into my branch and made the changes to support Oracle.
In regards to the docker Oracle XE Image - the dockerfile is on github so fine to use. I've had a look at http://docs.oracle.com/cd/B25329_01/doc/license.102/b25456/toc.htm and found it to be ok (would be worth you having a look).

[rnorth]

Hi Gurpreet
0.9.3 is released now with the modularization changes we discussed - 0.9.4 will be the next version, and is ready to receive your change.

Please could you refactor your PR into the altered project structure?

Please:

• make a new module under /modules/oracle-xe, but this should not be included in the default build
• set up a maven profile 'proprietary-deps' that includes the oracle-xe module into the build
• add your details to the root POM in the developer section (we should probably have an AUTHORS file too)...

[swissarmykirpan]

Hi Rich. I've updated the code to reflect the changes requested in your last comment.

[rnorth]

I imagine the Oracle JDBC driver needs to be added here - please make sure you're using the standard groupId:artifactId for it (can't remember what the convention is off the top of my head)

[swissarmykirpan]

Added

[rnorth]

Scope here and for dbutils seems to have changed - should be test, I think!

[rnorth]

Ah - sorry I just noticed: please use plain JDBC for the container liveness check, not Hikari.

Much as I love Hikari and think everyone should use it for their DB connection pooling needs, I'm not quite yet ready to force it upon everybody as a compile-scoped dependency. We should be able to use regular JDBC to do the liveness check.

(NB I know the presence of the zexec library goes against the above philosophy, and I'm mulling replacing it with a JDK-standard approach!)

[swissarmykirpan]

Keep the feedback coming!

[rnorth]

Hmm, attempting to merge this but the Oracle XE container seems to be blowing up. I can't understand how I'd be the first to see this, but it seems that the container has the wrong permissions set on its /var/run/sshd folder:

❯ docker run -p 1521:1521 alexeiled/docker-oracle-xe-11g                                                                                                                                                                        
Starting Oracle Net Listener.
Starting Oracle Database 11g Express Edition instance.

/var/run/sshd must be owned by root and not group or world-writable.

~/projects/tc git$master  28.9s
❯

I've confirmed that this does seem to be a trait of the container:

❯ docker run -p 1521:1521 -it alexeiled/docker-oracle-xe-11g /bin/bash                                                                                                                                                       
root@a386c8710f43:/# ls -al /var/run/sshd
total 8
drwxr-xr-x 2 oracle dba  4096 Jan 11  2014 .
drwxr-xr-x 7 root   root 4096 Jan 12  2014 ..
root@a386c8710f43:/# exit

I'm going to see whether the wnameless fork fares any better; it seems to be much more actively maintained at any rate...

[rnorth]

Went with wnameless in the end - @gusohal please confirm whether this is an issue for you.

[swissarmykirpan]

No problem at all. I didn't seem to have any issues with the original container. Weird.