Export function template

[kvch]

A new subcommand is added under export named function. This command prints the loadable template to stdout for enabled functions.

$ ./functionbeat export function cloudwatch

I extracted generating templates from CLIManager. Now it has a TemplateBuilder which constructs the template for the manager. A template builder can be retrieved from a provider, as generating templates is specific to providers. Thus, CLIManager does not need to know about the provider anymore.

TODO

• more testing
• changelog entry
• better PR description

[ph]

Haven't tested it, but code looks good nice refactoring @kvch, could we add a simple python system test to make sure it work?

[ph]

File "/usr/share/python-wheels/urllib3-1.19.1-py2.py3-none-any.whl/urllib3/util/retry.py", line 315, in increment
total -= 1
TypeError: unsupported operand type(s) for -=: 'Retry' and 'int'
../..//libbeat/scripts/Makefile:254: recipe for target 'python-env' failed

The above is weird, It's not in our code it's in the python library that we use.
I've rekicked the job on travis.

[ph]

I've tested the export function cloudwatch and the document produced appear to be complete and valid, I have added comment concerning the usage and the help provided by that command.

[kvch]

jenkins test this

[ph]

I just added a few minors comments concerning missing godoc and also a suggestion for the changelog, otherwise everything else LGTM.

[ph]

Failure appears to be related to the changes in this PR.

[kvch]

Failing tests are unrelated.