Check if the request log is enabled before requiring the context is initialized.

[axiak]

In 706a0f2,
the guard to initialize the request log based on the property was removed. This
causes a dependency on hystrix context initialization for all custom concurrency
strategies.

Here we add that back in, along with a test to ensure that a custom strategy could
still run without an initialized context.

This PR supercedes #718

/cc @mattrjacobs

[cloudbees-pull-request-builder]

NetflixOSS » Hystrix » Hystrix-pull-requests #71 FAILURE
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[cloudbees-pull-request-builder]

NetflixOSS » Hystrix » Hystrix-pull-requests #72 SUCCESS
This pull request looks good

[mattrjacobs]

Looks great - thanks for adding the unit test as well that exercises this case. I've gotten Cloudbees happy, so I'm merging this and will release it ASAP as 1.4.2

[axiak]

Thanks!

[axiak]

Hey @mattrjacobs, how long do you think it'll be until 1.4.2 is published? I want to upgrade all of our stuff ASAP. Thanks again

[mattrjacobs]

This was released yesterday afternoon: https://github.com/Netflix/Hystrix/releases/tag/v1.4.2

[axiak]

Doh. Our nexus proxy was caching the absence of it. Thanks again!

[axiak]

@mattrjacobs we're having an issue where the pom is defining hystrix's deps as scope runtime:
https://repo1.maven.org/maven2/com/netflix/hystrix/hystrix-core/1.4.2/hystrix-core-1.4.2.pom

The gradle.properties files claims these are at compile. Did something break in the release?

[mattrjacobs]

This also just got reported in #730 . AFAIK, I didn't change anything that would affect this in the Hystrix code itself. I'm looking through the CI configs to see if anything changed there.

[restfulhead]

A suggestion: It would be good to add a note about this here: https://github.com/Netflix/Hystrix/wiki/Plugins#concurrencystrategy

If I wouldn't have found this pull request, I would have never guessed that I have to set

ConfigurationManager.getConfigInstance().setProperty("hystrix.command.default.requestLog.enabled", "false");

to make a custom concurrency strategy work...