v0.42.0

This release contains a number of fixes and enhancements.

New built-in function: object.subset

This function checks if a collection is a subset of another collection. It works on objects, sets, and arrays.

If both arguments are objects, then the operation is recursive, e.g. {"c": {"x": {10, 15, 20}}
is considered a subset of {"a": "b", "c": {"x": {10, 15, 20, 25}, "y": "z"}.

See the built-in functions docs for all details

This implementation fixes #4358 and was authored by @charlesdaniels.

New keywords: "contains" and "if"

These new keywords let you increase the expressiveness of your policy code:

Before

package authz
allow { not denied } # `denied` left out for presentation purposes

deny[msg] {
    count(violations) > 0
    msg := sprintf("there are %d violations", [count(violations)])
}

After

package authz
import future.keywords

allow if not denied # one expression only => no { ... } needed!

deny contains msg if {
    count(violations) > 0
    msg := sprintf("there are %d violations", [count(violations)])
}

Note that rule bodies containing only one expression can be abbreviated when using if.

To use the new keywords, use import future.keywords.contains and import future.keywords.if; or import all of them at once via import future.keywords. When these future imports are present, the pretty printer (opa fmt) will introduce contains and if where applicable.

if is allowed in all places to separate the rule head from the body, like

response[key] = value if { key := "open", y := "sesame" }

but not for partial set rules, unless also using contains:

deny[msg]         if msg := "forbidden" # INVALID
deny contains msg if msg := "forbidden" # VALID

Tooling, SDK, and Runtime

• Plugins:
  • S3 Plugin: Allow multiple AWS credential providers at once, chained together (#4791), reported and authored by @abhisek
  • Discovery Plugin: Check for empty key config (#4656) reported by @humbertoc-silva
  • Logs Plugin: Update mechanism to escape field paths (#4717) reported by @pauly4it
  • Status Plugin: fix bundle_failed_load_counter metric for bundles without revisions (#4822) reported and authored by @jkbschmid
• Server: The system.authz policy now properly supports the interquery caching of http.send calls (#4829), reported by @HarshPathakhp
• opa bench: Passing --e2e makes the benchmark measure the performance of a query including the server's HTTP handlers and their processing.
• opa fmt: Output list and diff changes with --fail flag (#4710) (authored by @davidkuridza)
• Disk Storage: Bundles are now streamed into the disk store, and not extracted completely in-memory (#4539)
• Golang package repl: Add a WithCapabilities function (authored by @jaspervdj)
• SDK: Allow configurable ID (authored by @rakshasa-1729)
• Windows: User lookups in various code paths have been avoided. They had no use, but are costly, and removing them should increase
  the performance of any CLI calls (even opa version) on Windows. Fixes #4646.
• Server: Fix performance regression in Query API handler by opening a "read" storage transaction (not "write")

Rego and Topdown

• Runtime Errors: Fix type error message in count, object.filter, and object.remove built-in functions (#4767)
• Parser: Remove early MHS return in infix parsing, fixing confusing error messages (#4672) authored by @philipaconrad
• AST: Disallow shadowing of called functions in comprehension heads (#4762)
• Planner/IR: shadow rule funcs if mocking functions (#4746)
• Compiler: Fix "every" handling in partial eval: by reordering body for safety differently, and correctly plugging its terms on safe (#4801), reported by @jguenther-va
• Compiler: fix util.HashMap eq comparison (#4759)
• Built-ins: use strings.Builder in glob.match() (authored by @charlesdaniels)

Documentation

• Builtins: Fix documentation of startswith and endswith (authored by @whme)
• Kubenetes Tutorial: Remove unused assignement in example (#4778) authored by @Joffref
• OCI: Update configuration docs for private images in OCI registries (authored by @carabasdaniel)
• AWS S3 Signing: Fix profile_credentials docs (authored by @wangli1030)

Website + Ecosystem

• Add "Edit on GitHub" button to docs (#3784) authored by @avinashdesireddy
• Wasm: fix function table markup (#4664)
• Ecosystem: use location.hash to track open modal (#4667)

Note that website changes like these become effective immediately and are not tied to a release.
We still use our release notes to record the nice fixed contributed by our community.

• Ecosystem Additions:
  • Alfred, the self-hosted playground (authored by @dolevf)
  • Java Spring tutorial (authored by @psevestre)
  • Pulumi

Miscellaneous

• Add Terminus to ADOPTERS.md (#4734) (#4713) reported by @charlieflowers
• Remove any data attributes not used in the "YAML tests" (#4813)
• Dependency bumps, notably:
  • github.com/prometheus/client_golang 1.12.2 (#4697)
  • github.com/vektah/gqlparser/v2 2.4.5
• Build process and CI:
  • Use Trivy for vulnerability scans in code and container images (authored by @JAORMX)
  • Bump golangci-lint to v1.46.2, fix some issues (#4765)
  • Remove npm-opa-wasm test
  • Skip flaky darwin tests on PR runs
  • Fix flaky oci e2e test (#4748) authored by @carabasdaniel
  • Integrate builtin_metadata.json handling in release process (#4754)