Take with timestamp

[nicor88]

Add take_with_timestamp

Description

I'm currently using the take method of a stream in production. I have some cases where I would like to have not only the batch of values but a batch of values with the timestamp of when the message was inserted into kafka.

This PR adds a new method called take_with_timestamp, it works exactly like take, but it adds the Kafka timestamp to each returned value.

I tested in a local environment and seems working as expected, the real difference with take is this:

value[timestamp_field_name] = event.message.timestamp

the name of the timestamp must be passed as an argument, to force to pass the name, some people might like kafka_timestamp, some event_timestamp, I preferred to leave it generic.

[nicor88]

@patkivikram and @ekerstens I saw that you are pretty active, could you have a look? 🙏

[taybin]

The code looks clean to me, but I think for a user facing function, there really needs to be a unit test of some kind for it.

[nicor88]

@taybin could you have a look again? I added 3 tests, should cover the most essentials parts.

[codecov-commenter]

Codecov Report

Merging #242 (22a1924) into master (8d8971a) will decrease coverage by 0.05%.
The diff coverage is 82.69%.

@@            Coverage Diff             @@
##           master     #242      +/-   ##
==========================================
- Coverage   94.32%   94.26%   -0.06%     
==========================================
  Files         100      100              
  Lines       10762    10814      +52     
  Branches     1472     1477       +5     
==========================================
+ Hits        10151    10194      +43     
- Misses        542      549       +7     
- Partials       69       71       +2     

Impacted Files	Coverage Δ
faust/streams.py	96.26% <82.69%> (-1.46%)	⬇️

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[nicor88]

@patkivikram if you have some time to look into that would be amazing, it's pretty trivial. Many thanks.