STORM-2597: Don't parse passed in class paths

[revans2]

No description provided.

[harshach]

@revans2 this means the users exported STORM_EXT_CLASSPATH must contain a wildcard "*"
This could result in issues with current users who are just passing the dir and not adding a wildcard and if they have multiple jars in that dir because of this change it will break right

[revans2]

@harshach yes this will cause issues with anyone currently setting a classpath to a directory that has jars in it. But it also make it behave like a java classpath currently does everywhere else.

I am not proposing that we backport this to 1.x, but going forward I would like to see it act differently.

[HeartSaVioR]

@revans2 @harshach
I've just played with get_wildcard_dir() and found another issues. Please refer below:

>>> import os
>>> def get_wildcard_dir(path):
...     if os.path.isdir(path):
...         ret = [(os.path.join(path, "*"))]
...     elif os.path.exists(path):
...         ret = [path]
...     return ret
...
>>> get_wildcard_dir("~/WorkArea")
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<stdin>", line 6, in get_wildcard_dir
UnboundLocalError: local variable 'ret' referenced before assignment
>>> get_wildcard_dir("/Users/jlim/WorkArea")
['/Users/jlim/WorkArea/*']
>>> get_wildcard_dir("/Users/jlim/WorkArea/*")
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<stdin>", line 6, in get_wildcard_dir
UnboundLocalError: local variable 'ret' referenced before assignment

So get_wildcard_dir() just fails when a part of classpath contains not a dir nor a existing file.
(It even seems not handle ~ character.)
IIRC we don't guide the format of STORM_EXT_CLASSPATH and STORM_EXT_CLASSPATH_DAEMON and then what I expect is the format of Java class path pattern.

I'm +1 for the change. This is a bug hence actually need to port back to 1.x version line, but it might break backward compatibility so not having strong opinion about back port.

Maybe need to fix get_wildcard_dir() as well. Which value we want to return when it's not a dir nor an existing file? Same return value as an existing file? [] to effectively get rid of input to the classpath?

[revans2]

Sounds good. I'll merge it in, and see what, if anything I need to do to pull this into older version of storm too.