Open Policy Agent - v0.9.0

Major Features

This release adds two major features to OPA itself.

• Query Profiler: the opa eval subcommand now supports a --profiler option
  to help policy authors understand the performance profile of their policies.
  Give it a shot and let us know if you find it helpful or if you find cases
  that could be improved!

• Compile API: OPA now exposes Partial Evaluation with first-class interfaces.
  In prior releases, Partial Evaluation was only used for optimizations
  purposes. As of v0.9, callers can use Partial Evaluation via HTTP or Golang to
  obtain conditional decisions that can be evaluated on the client-side.

Fixes

• Add ADOPTERS.md file (#691)
• Add time.weekday builtin (#789)
• Fix REPL output for multiple bool exprs (#850)
• Remove support rule if default value is not needed (#820)

Miscellaneous

Here is a shortlist of notable miscellaenous improvements.

• Add any/all built-in functions (thanks @vrnmthr)
• Add built-in function to parse Rego modules
• Add copy propagation optimization to partial evaluation output
• Add docs for exercising policies with test framework
• Add extra output formats to eval subcommand
• Add support for providing input to eval via stdin
• Improve parser error readability
• Improve rule index to support unknown values
• Rewrite == with = in compiler
• Update build to enable CGO

...along with 30+ other fixes and improvements.