Extend Action interface by client variables

As per our design on [Specifying environment
variables](http://bazel.io/designs/2016/06/21/environment.html), actions may
depend, in a controlled way, on the environment in which the Bazel client
is invoked. Those environment variables are considered essential for the
action, in the sense that it was to be repeated if either of them changes their
value (note that other variables in client environment may well change without
invalidating actions). Therefore, make the variables that need to be taken from
the client environment part of the meta data for actions.

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Change-Id: I2ff6cf40b4ce8e0fea5c7e464f5f3b3e693025ac
Reviewed-on: https://bazel-review.googlesource.com/#/c/5390
MOS_MIGRATED_REVID=131150211
11 files changed
tree: fa17615a3f769f030df889b61e8f7f9bbb1a8dee
  1. examples/
  2. scripts/
  3. site/
  4. src/
  5. third_party/
  6. tools/
  7. .gitattributes
  8. .gitignore
  9. AUTHORS
  10. BUILD
  11. CHANGELOG.md
  12. compile.sh
  13. CONTRIBUTING.md
  14. CONTRIBUTORS
  15. LICENSE.txt
  16. README.md
  17. WORKSPACE
README.md

Bazel (Beta)

{Fast, Correct} - Choose two

Bazel is a build tool that builds code quickly and reliably. It is used to build the majority of Google‘s software, and thus it has been designed to handle build problems present in Google’s development environment, including:

  • A massive, shared code repository, in which all software is built from source. Bazel has been built for speed, using both caching and parallelism to achieve this. Bazel is critical to Google's ability to continue to scale its software development practices as the company grows.

  • An emphasis on automated testing and releases. Bazel has been built for correctness and reproducibility, meaning that a build performed on a continuous build machine or in a release pipeline will generate bitwise-identical outputs to those generated on a developer's machine.

  • Language and platform diversity. Bazel's architecture is general enough to support many different programming languages within Google, and can be used to build both client and server software targeting multiple architectures from the same underlying codebase.

Find more background about Bazel in our FAQ.

Getting Started

About the Bazel project: