Updates to NASA Auth plugins and examples

[reidsunderland]

So far, my NASA authentication plugin has only been used in subscribe/sarra components to download files posted by polls. In those cases, the polls don't require any authentication.

In a case @andreleblanc11 is dealing with, the poll part also needs to authenticate.

I refactored the code to make it easier to call the authentication code from a poll. I also added an authenticate directory under flowcb for similar plugins.

The poll can authenticate by adding a small plugin that looks like this:

import sarracenia
import sarracenia.flowcb.authenticate.nasa_earthdata
import logging

logger = logging.getLogger(__name__)

class Nasa_omisips(sarracenia.flowcb.poll.Poll):
    def __init__(self, options):
        super().__init__(options, logger)
        self.auth = sarracenia.flowcb.authenticate.nasa_earthdata.Nasa_earthdata(options)
    
    def poll(self) -> list:
        # Inject bearer token in the credentials
        self.auth.add_token_for_url(self.o.pollUrl)

        # Run the normal HTTP poll, now that the bearer token has been
        # injected in the credentials DB it should work
        return super().poll()

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Additionally, the poll_NASA_CMR plugin was broken. I think something changed recently to enforce having a pollUrl in a poll config file. When setting pollUrl in the config, I also had to start using the msg['post_baseUrl'] option added in #951.

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I also updated related examples to match the changed plugin location/name.

[github-actions]

Test Results

209 tests   201 ✅  17s ⏱️
  1 suites    8 💤
  1 files      0 ❌

Results for commit 0b34d9d.