Allow longer Class-Path entries

[shanemhansen]

jar Class-Path entries have a max line length which, when exceeded, will cause java to fail to start. See: https://docs.oracle.com/javase/8/docs/technotes/guides/jar/jar.html Use newline plus extra space to support large numbers of jar files.

R: @robertwb FIXES: #23268

Tested: via standalone monkey-patched version of method and later via unit test below:

tox -e py39 -- apache_beam/utils/subprocess_server_test.py

Also did some quick and dirty manual tests to ensure code path for generating jar was covered subprocess_server_test.py. Confirmed:

• ' '.join(classpath) (previous impl) works for unit test
• '\n '.join(classpath) (current impl) works for unit test
• ' x'.join(classpath) fails

[codecov[bot]]

Codecov Report

Merging #23269 (17bfa64) into master (30a48f0) will decrease coverage by 0.01%. The diff coverage is n/a.

@@            Coverage Diff             @@
##           master   #23269      +/-   ##
==========================================
- Coverage   73.60%   73.58%   -0.02%     
==========================================
  Files         716      716              
  Lines       95334    95334              
==========================================
- Hits        70171    70155      -16     
- Misses      23867    23883      +16     
  Partials     1296     1296              

Flag	Coverage Δ
python	83.40% <ø> (-0.03%)	:arrow_down:

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
sdks/python/apache_beam/utils/subprocess_server.py	58.73% <ø> (ø)
.../python/apache_beam/testing/test_stream_service.py	88.09% <0.00%> (-4.77%)	:arrow_down:
...ks/python/apache_beam/runners/worker/data_plane.py	87.57% <0.00%> (-1.70%)	:arrow_down:
...che_beam/runners/interactive/interactive_runner.py	90.06% <0.00%> (-1.33%)	:arrow_down:
...eam/runners/portability/fn_api_runner/execution.py	92.44% <0.00%> (-0.65%)	:arrow_down:
...ks/python/apache_beam/runners/worker/sdk_worker.py	88.94% <0.00%> (-0.64%)	:arrow_down:
sdks/python/apache_beam/runners/common.py	88.59% <0.00%> (-0.25%)	:arrow_down:
...on/apache_beam/runners/dataflow/dataflow_runner.py	82.87% <0.00%> (-0.14%)	:arrow_down:
...hon/apache_beam/runners/worker/bundle_processor.py	93.54% <0.00%> (ø)
sdks/python/apache_beam/transforms/util.py	96.22% <0.00%> (+0.15%)	:arrow_up:
... and 3 more

:mega: We’re building smart automated test selection to slash your CI/CD build times. Learn more

[github-actions[bot]]

Assigning reviewers. If you would like to opt out of this review, comment assign to next reviewer:

R: @y1chi for label python.

Available commands:

• stop reviewer notifications - opt out of the automated review tooling
• remind me after tests pass - tag the comment author after tests pass
• waiting on author - shift the attention set back to the author (any comment or push by the author will return the attention set to the reviewers)

The PR bot will only process comments in the main thread (not review comments).

[shanemhansen]

Not sure if I'm doing this right. I thought the bot assigned a reviewer, but maybe that was a suggestion. Let's try: R: @y1chi

[github-actions[bot]]

Stopping reviewer notifications for this pull request: review requested by someone other than the bot, ceding control