Added support for AWS Sigv4 for UrlLib3.

[dblock]

Description

• Adds SigV4 support for Urllib3HttpConnection.
• Deprecates AWSV4SignerAuth in favor of RequestsAWSV4SignerAuth
• Uses Urllib3AWSV4SignerAuth in the documentation since that transport is faster.

Testing

AOS

export SERVICE=es
export ENDPOINT=https://xyz.us-west-2.aoss.amazonaws.com
poetry run python sigv4/urllib3-hello.py 

INFO:Found credentials in environment variables.
INFO:GET https://search-dblock-test-opensearch-27-xyz.us-west-2.es.amazonaws.com:443/ [status:200 request:0.768s]
opensearch: 2.7.0
INFO:PUT https://search-dblock-test-opensearch-27-xyz.us-west-2.es.amazonaws.com:443/movies [status:200 request:2.298s]
INFO:PUT https://search-dblock-test-opensearch-27-xyz.us-west-2.es.amazonaws.com:443/movies/_doc/1 [status:201 request:0.500s]
INFO:POST https://search-dblock-test-opensearch-27-xyz.us-west-2.es.amazonaws.com:443/_search [status:200 request:0.213s]
{'director': 'Bennett Miller', 'title': 'Moneyball', 'year': 2011}
INFO:DELETE https://search-dblock-test-opensearch-27-xyz.us-west-2.es.amazonaws.com:443/movies/_doc/1 [status:200 request:0.108s]
INFO:DELETE https://search-dblock-test-opensearch-27-xyz.us-west-2.es.amazonaws.com:443/movies [status:200 request:0.223s]

AOSS

export SERVICE=aoss
export ENDPOINT=https://xyz.us-west-2.aoss.amazonaws.com
poetry run python sigv4/urllib3-hello.py 

INFO:Found credentials in environment variables.
INFO:PUT https://xyz.us-west-2.aoss.amazonaws.com:443/movies [status:200 request:4.173s]
INFO:PUT https://xyz.us-west-2.aoss.amazonaws.com:443/movies/_doc/1 [status:201 request:3.117s]
INFO:POST https://xyz.us-west-2.aoss.amazonaws.com:443/_search [status:200 request:4.916s]
{'director': 'Bennett Miller', 'title': 'Moneyball', 'year': 2011}
INFO:DELETE https://xyz.us-west-2.aoss.amazonaws.com:443/movies/_doc/1 [status:200 request:1.249s]
INFO:DELETE https://xyz.us-west-2.aoss.amazonaws.com:443/movies [status:200 request:0.168s]

Issues Resolved

Closes #546

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[codecov]

Codecov Report

Merging #547 (284a5fd) into main (fa8f3a7) will increase coverage by 0.02%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main     #547      +/-   ##
==========================================
+ Coverage   70.63%   70.66%   +0.02%     
==========================================
  Files          83       83              
  Lines        7857     7877      +20     
==========================================
+ Hits         5550     5566      +16     
- Misses       2307     2311       +4     

Files	Coverage Δ
opensearchpy/__init__.py	92.85% <100.00%> (ø)
opensearchpy/connection/http_urllib3.py	82.00% <100.00%> (-4.03%)	⬇️
opensearchpy/helpers/__init__.py	100.00% <100.00%> (ø)
opensearchpy/helpers/signer.py	98.03% <100.00%> (+3.30%)	⬆️

... and 2 files with indirect coverage changes

[dblock]

@harshavamsi would appreciate your CR since you did support for the requests connection class.

[VachaShah]

Do we need this license here?

[dblock]

Yes, this code was refactored out of test_connection.py, so let's keep it.

[VachaShah]

Do we recommend Urllib3AWSV4SignerAuth here?

[dblock]

I've clarified the documentation in cb76874.

[VachaShah]

RequestsAWSV4SignerAuth returns prepared request while Urllib3AWSV4SignerAuth returns the headers, should we keep them consistent?

[dblock]

The requests library expect a callable that derives from requests.auth.AuthBase and receives a request object. It's called inside the requests library.

The urllib3 library doesn't support such an interface. It actually splits the client constructor and exposes a perform_request method. That's where we have the method, URL, and body, and call auth. There's no "request" object here.

We could make a similar interface to AuthBase for urllib3, but it cannot be the same interface because that one exists in the requests library. Since these signer classes aren't interchangeable at all, they don't need to derive from the same class, and I already moved the common parts into AWSV4Signer.

[VachaShah]

That makes sense, thank you!

[dblock]

@VachaShah I wrote some more tests and addressed your comments. LMK if there's anything else needed for this one

[VachaShah]

LGTM!