Deduplicate jq filter compile/cache pipeline in jqschema without changing public behavior

[Copilot]

CompileToolResponseFilter and CompileToolResponseFilterWithVars duplicated the same cache-check → parse → compile → cache-store flow, forcing parallel maintenance of error/log/cache behavior. This refactor consolidates that pipeline into one internal path while preserving the two intentional behavioral differences (cache key shape and compile options).

• Refactor: shared internal compile path

  • Introduced compileToolResponseFilterInternal[K comparable] to centralize:
    • cache lookup/type guard
    • jq parse/compile error wrapping
    • cache store
    • common logging lifecycle
  • Kept wrappers thin and explicit for each public API.

• Preserved API-specific behavior

  • CompileToolResponseFilter still uses:
    • cache key: raw filter string
    • compile options: secureCompileOpts
  • CompileToolResponseFilterWithVars still uses:
    • cache key: toolResponseFilterVarsCacheKey{filter, varNamesKey}
    • compile options: compileOptsWithVariables(varNames)
    • var-aware log context

• Coverage update for cache-key separation

  • Added a focused test asserting that compiling the same filter through plain and vars-enabled APIs does not reuse the same cached *gojq.Code.

func CompileToolResponseFilter(filter string) (*gojq.Code, error) {
	return compileToolResponseFilterInternal(
		filter, filter, secureCompileOpts, "CompileToolResponseFilter", "",
	)
}

func CompileToolResponseFilterWithVars(filter string, varNames []string) (*gojq.Code, error) {
	cacheKey := toolResponseFilterVarsCacheKey{
		filter:      filter,
		varNamesKey: buildVarNamesCacheKey(varNames),
	}
	return compileToolResponseFilterInternal(
		cacheKey, filter, compileOptsWithVariables(varNames),
		"CompileToolResponseFilterWithVars", fmt.Sprintf(", vars=%v", varNames),
	)
}

[Copilot]

Pull request overview

This PR refactors the jq tool-response filter compilation logic in internal/middleware/jqschema.go by consolidating the shared cache lookup → parse → compile → cache store pipeline into a single internal helper, while keeping the two public entry points’ intentional differences (cache-key shape and compile options) intact.

Changes:

• Introduced a shared internal compile function (compileToolResponseFilterInternal) to deduplicate cache/compile flow and logging.
• Kept CompileToolResponseFilter and CompileToolResponseFilterWithVars as thin wrappers to preserve API-specific behavior.
• Added a coverage test ensuring the plain and var-enabled APIs do not share cached compiled code.

Show a summary per file

File	Description
internal/middleware/jqschema.go	Deduplicates the filter compile/cache pipeline into a shared internal helper while preserving wrapper-level behavior differences.
internal/middleware/jqschema_coverage_test.go	Adds a focused test ensuring cache-key separation between plain vs var-enabled compilation paths.

Review details

Tip

Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

• Files reviewed: 2/2 changed files
• Comments generated: 2
• Review effort level: Low