// Copyright 2018 The OPA Authors. All rights reserved. // Use of this source code is governed by an Apache2 // license that can be found in the LICENSE file. package cmd import ( "bytes" "context" "errors" "fmt" "io" "os" "strconv" "strings" "time" "github.com/spf13/cobra" "github.com/open-policy-agent/opa/ast" "github.com/open-policy-agent/opa/ast/location" "github.com/open-policy-agent/opa/bundle" "github.com/open-policy-agent/opa/compile" "github.com/open-policy-agent/opa/cover" fileurl "github.com/open-policy-agent/opa/internal/file/url" pr "github.com/open-policy-agent/opa/internal/presentation" "github.com/open-policy-agent/opa/internal/runtime" "github.com/open-policy-agent/opa/loader" "github.com/open-policy-agent/opa/metrics" "github.com/open-policy-agent/opa/profiler" "github.com/open-policy-agent/opa/rego" "github.com/open-policy-agent/opa/topdown" "github.com/open-policy-agent/opa/topdown/lineage" "github.com/open-policy-agent/opa/util" ) type evalCommandParams struct { capabilities *capabilitiesFlag coverage bool partial bool unknowns []string disableInlining []string shallowInlining bool disableIndexing bool disableEarlyExit bool strictBuiltinErrors bool dataPaths repeatedStringFlag inputPath string imports repeatedStringFlag pkg string stdin bool stdinInput bool explain *util.EnumFlag metrics bool instrument bool ignore []string outputFormat *util.EnumFlag profile bool profileCriteria repeatedStringFlag profileLimit intFlag count int prettyLimit intFlag fail bool failDefined bool bundlePaths repeatedStringFlag schema *schemaFlags target *util.EnumFlag timeout time.Duration optimizationLevel int entrypoints repeatedStringFlag strict bool } func newEvalCommandParams() evalCommandParams { return evalCommandParams{ capabilities: newcapabilitiesFlag(), outputFormat: util.NewEnumFlag(evalJSONOutput, []string{ evalJSONOutput, evalValuesOutput, evalBindingsOutput, evalPrettyOutput, evalSourceOutput, evalRawOutput, }), explain: newExplainFlag([]string{explainModeOff, explainModeFull, explainModeNotes, explainModeFails, explainModeDebug}), target: util.NewEnumFlag(compile.TargetRego, []string{compile.TargetRego, compile.TargetWasm}), count: 1, profileCriteria: newrepeatedStringFlag([]string{}), profileLimit: newIntFlag(defaultProfileLimit), prettyLimit: newIntFlag(defaultPrettyLimit), schema: &schemaFlags{}, } } func validateEvalParams(p *evalCommandParams, cmdArgs []string) error { if len(cmdArgs) > 0 && p.stdin { return errors.New("specify query argument or --stdin but not both") } else if len(cmdArgs) == 0 && !p.stdin { return errors.New("specify query argument or --stdin") } else if len(cmdArgs) > 1 { return errors.New("specify at most one query argument") } if p.stdin && p.stdinInput { return errors.New("specify --stdin or --stdin-input but not both") } if p.stdinInput && p.inputPath != "" { return errors.New("specify --stdin-input or --input but not both") } if p.fail && p.failDefined { return errors.New("specify --fail or --fail-defined but not both") } of := p.outputFormat.String() if p.partial && of != evalPrettyOutput && of != evalJSONOutput && of != evalSourceOutput { return errors.New("invalid output format for partial evaluation") } else if !p.partial && of == evalSourceOutput { return errors.New("invalid output format for evaluation") } if p.optimizationLevel > 0 { if len(p.dataPaths.v) > 0 && p.bundlePaths.isFlagSet() { return fmt.Errorf("specify either --data or --bundle flag with optimization level greater than 0") } } if p.profileLimit.isFlagSet() || p.profileCriteria.isFlagSet() { p.profile = true } if p.profile { p.metrics = true } if p.instrument { p.metrics = true } return nil } const ( evalJSONOutput = "json" evalValuesOutput = "values" evalBindingsOutput = "bindings" evalPrettyOutput = "pretty" evalSourceOutput = "source" evalRawOutput = "raw" // number of profile results to return by default defaultProfileLimit = 10 defaultPrettyLimit = 80 ) type regoError struct{} func (regoError) Error() string { return "rego" } func init() { params := newEvalCommandParams() evalCommand := &cobra.Command{ Use: "eval ", Short: "Evaluate a Rego query", Long: `Evaluate a Rego query and print the result. Examples -------- To evaluate a simple query: $ opa eval 'x := 1; y := 2; x < y' To evaluate a query against JSON data: $ opa eval --data data.json 'name := data.names[_]' To evaluate a query against JSON data supplied with a file:// URL: $ opa eval --data file:///path/to/file.json 'data' File & Bundle Loading --------------------- The --bundle flag will load data files and Rego files contained in the bundle specified by the path. It can be either a compressed tar archive bundle file or a directory tree. $ opa eval --bundle /some/path 'data' Where /some/path contains: foo/ | +-- bar/ | | | +-- data.json | +-- baz.rego | +-- manifest.yaml The JSON file 'foo/bar/data.json' would be loaded and rooted under 'data.foo.bar' and the 'foo/baz.rego' would be loaded and rooted under the package path contained inside the file. Only data files named data.json or data.yaml will be loaded. In the example above the manifest.yaml would be ignored. See https://www.openpolicyagent.org/docs/latest/management-bundles/ for more details on bundle directory structures. The --data flag can be used to recursively load ALL *.rego, *.json, and *.yaml files under the specified directory. The -O flag controls the optimization level. By default, optimization is disabled (-O=0). When optimization is enabled the 'eval' command generates a bundle from the files provided with either the --bundle or --data flag. This bundle is semantically equivalent to the input files however the structure of the files in the bundle may have been changed by rewriting, inlining, pruning, etc. This resulting optimized bundle is used to evaluate the query. If optimization is enabled at least one entrypoint must be supplied, either via the -e option, or via entrypoint metadata annotations. Output Formats -------------- Set the output format with the --format flag. --format=json : output raw query results as JSON --format=values : output line separated JSON arrays containing expression values --format=bindings : output line separated JSON objects containing variable bindings --format=pretty : output query results in a human-readable format --format=source : output partial evaluation results in a source format --format=raw : output the values from query results in a scripting friendly format Schema ------ The -s/--schema flag provides one or more JSON Schemas used to validate references to the input or data documents. Loads a single JSON file, applying it to the input document; or all the schema files under the specified directory. $ opa eval --data policy.rego --input input.json --schema schema.json $ opa eval --data policy.rego --input input.json --schema schemas/ Capabilities ------------ When passing a capabilities definition file via --capabilities, one can restrict which hosts remote schema definitions can be retrieved from. For example, a capabilities.json containing { "builtins": [ ... ], "allow_net": [ "kubernetesjsonschema.dev" ] } would disallow fetching remote schemas from any host but "kubernetesjsonschema.dev". Setting allow_net to an empty array would prohibit fetching any remote schemas. Not providing a capabilities file, or providing a file without an allow_net key, will permit fetching remote schemas from any host. Note that the metaschemas http://json-schema.org/draft-04/schema, http://json-schema.org/draft-06/schema, and http://json-schema.org/draft-07/schema, are always available, even without network access. `, PreRunE: func(cmd *cobra.Command, args []string) error { return validateEvalParams(¶ms, args) }, Run: func(cmd *cobra.Command, args []string) { defined, err := eval(args, params, os.Stdout) if err != nil { if _, ok := err.(regoError); !ok { fmt.Fprintln(os.Stderr, err) } os.Exit(2) } if (params.fail && !defined) || (params.failDefined && defined) { os.Exit(1) } }, } // Eval specific flags evalCommand.Flags().BoolVarP(¶ms.coverage, "coverage", "", false, "report coverage") evalCommand.Flags().StringArrayVarP(¶ms.disableInlining, "disable-inlining", "", []string{}, "set paths of documents to exclude from inlining") evalCommand.Flags().BoolVarP(¶ms.shallowInlining, "shallow-inlining", "", false, "disable inlining of rules that depend on unknowns") evalCommand.Flags().BoolVar(¶ms.disableIndexing, "disable-indexing", false, "disable indexing optimizations") evalCommand.Flags().BoolVar(¶ms.disableEarlyExit, "disable-early-exit", false, "disable 'early exit' optimizations") evalCommand.Flags().BoolVarP(¶ms.strictBuiltinErrors, "strict-builtin-errors", "", false, "treat built-in function errors as fatal") evalCommand.Flags().BoolVarP(¶ms.instrument, "instrument", "", false, "enable query instrumentation metrics (implies --metrics)") evalCommand.Flags().BoolVarP(¶ms.profile, "profile", "", false, "perform expression profiling") evalCommand.Flags().VarP(¶ms.profileCriteria, "profile-sort", "", "set sort order of expression profiler results") evalCommand.Flags().VarP(¶ms.profileLimit, "profile-limit", "", "set number of profiling results to show") evalCommand.Flags().VarP(¶ms.prettyLimit, "pretty-limit", "", "set limit after which pretty output gets truncated") evalCommand.Flags().BoolVarP(¶ms.failDefined, "fail-defined", "", false, "exits with non-zero exit code on defined/non-empty result and errors") evalCommand.Flags().DurationVar(¶ms.timeout, "timeout", 0, "set eval timeout (default unlimited)") evalCommand.Flags().IntVarP(¶ms.optimizationLevel, "optimize", "O", 0, "set optimization level") evalCommand.Flags().VarP(¶ms.entrypoints, "entrypoint", "e", "set slash separated entrypoint path") // Shared flags addCapabilitiesFlag(evalCommand.Flags(), params.capabilities) addPartialFlag(evalCommand.Flags(), ¶ms.partial, false) addUnknownsFlag(evalCommand.Flags(), ¶ms.unknowns, []string{"input"}) addFailFlag(evalCommand.Flags(), ¶ms.fail, false) addDataFlag(evalCommand.Flags(), ¶ms.dataPaths) addBundleFlag(evalCommand.Flags(), ¶ms.bundlePaths) addInputFlag(evalCommand.Flags(), ¶ms.inputPath) addImportFlag(evalCommand.Flags(), ¶ms.imports) addPackageFlag(evalCommand.Flags(), ¶ms.pkg) addQueryStdinFlag(evalCommand.Flags(), ¶ms.stdin) addInputStdinFlag(evalCommand.Flags(), ¶ms.stdinInput) addMetricsFlag(evalCommand.Flags(), ¶ms.metrics, false) addOutputFormat(evalCommand.Flags(), params.outputFormat) addIgnoreFlag(evalCommand.Flags(), ¶ms.ignore) setExplainFlag(evalCommand.Flags(), params.explain) addSchemaFlags(evalCommand.Flags(), params.schema) addTargetFlag(evalCommand.Flags(), params.target) addCountFlag(evalCommand.Flags(), ¶ms.count, "benchmark") addStrictFlag(evalCommand.Flags(), ¶ms.strict, false) RootCommand.AddCommand(evalCommand) } func eval(args []string, params evalCommandParams, w io.Writer) (bool, error) { ctx := context.Background() if params.timeout != 0 { var cancel func() ctx, cancel = context.WithTimeout(ctx, params.timeout) defer cancel() } ectx, err := setupEval(args, params) if err != nil { return false, err } ectx.regoArgs = append(ectx.regoArgs, rego.EnablePrintStatements(true), rego.PrintHook(topdown.NewPrintHook(os.Stderr))) results := make([]pr.Output, ectx.params.count) profiles := make([][]profiler.ExprStats, ectx.params.count) timers := make([]map[string]interface{}, ectx.params.count) for i := 0; i < ectx.params.count; i++ { results[i] = evalOnce(ctx, ectx) profiles[i] = results[i].Profile if ts, ok := results[i].Metrics.(metrics.TimerMetrics); ok { timers[i] = ts.Timers() } } result := results[0] if ectx.params.count > 1 { result.Profile = nil result.Metrics = nil result.AggregatedProfile = profiler.AggregateProfiles(profiles...) timersAggregated := map[string]interface{}{} for name := range timers[0] { var vals []int64 for _, t := range timers { val, ok := t[name].(int64) if !ok { return false, fmt.Errorf("missing timer for %s" + name) } vals = append(vals, val) } timersAggregated[name] = metrics.Statistics(vals...) } result.AggregatedMetrics = timersAggregated } switch ectx.params.outputFormat.String() { case evalBindingsOutput: err = pr.Bindings(w, result) case evalValuesOutput: err = pr.Values(w, result) case evalPrettyOutput: err = pr.Pretty(w, result) case evalSourceOutput: err = pr.Source(w, result) case evalRawOutput: err = pr.Raw(w, result) default: err = pr.JSON(w, result) } if err != nil { return false, err } else if len(result.Errors) > 0 { // If the rego package returned an error, return a special error here so // that the command doesn't print the same error twice. The error will // have been printed above by the presentation package. return false, regoError{} } else if len(result.Result) == 0 { return false, nil } return true, nil } func evalOnce(ctx context.Context, ectx *evalContext) pr.Output { var result pr.Output var resultErr error var parsedModules map[string]*ast.Module if ectx.metrics != nil { ectx.metrics.Clear() } if ectx.profiler != nil { ectx.profiler.reset() } r := rego.New(ectx.regoArgs...) if !ectx.params.partial { var pq rego.PreparedEvalQuery pq, resultErr = r.PrepareForEval(ctx) if resultErr == nil { parsedModules = pq.Modules() result.Result, resultErr = pq.Eval(ctx, ectx.evalArgs...) } } else { var pq rego.PreparedPartialQuery pq, resultErr = r.PrepareForPartial(ctx) if resultErr == nil { parsedModules = pq.Modules() result.Partial, resultErr = pq.Partial(ctx, ectx.evalArgs...) resetExprLocations(result.Partial) } } result.Errors = pr.NewOutputErrors(resultErr) if ectx.params.explain != nil { switch ectx.params.explain.String() { case explainModeDebug: result.Explanation = lineage.Debug(*(ectx.tracer)) case explainModeFull: result.Explanation = lineage.Full(*(ectx.tracer)) case explainModeNotes: result.Explanation = lineage.Notes(*(ectx.tracer)) case explainModeFails: result.Explanation = lineage.Fails(*(ectx.tracer)) } } if ectx.metrics != nil { result.Metrics = ectx.metrics } if ectx.params.profile { var sortOrder = pr.DefaultProfileSortOrder if len(ectx.params.profileCriteria.v) != 0 { sortOrder = getProfileSortOrder(strings.Split(ectx.params.profileCriteria.String(), ",")) } result.Profile = ectx.profiler.p.ReportTopNResults(ectx.params.profileLimit.v, sortOrder) } if ectx.params.coverage { report := ectx.cover.Report(parsedModules) result.Coverage = &report } return result } type evalContext struct { params evalCommandParams metrics metrics.Metrics profiler *resettableProfiler cover *cover.Cover tracer *topdown.BufferTracer regoArgs []func(*rego.Rego) evalArgs []rego.EvalOption } func setupEval(args []string, params evalCommandParams) (*evalContext, error) { var query string if params.stdin { bs, err := io.ReadAll(os.Stdin) if err != nil { return nil, err } query = string(bs) } else { query = args[0] } info, err := runtime.Term(runtime.Params{}) if err != nil { return nil, err } regoArgs := []func(*rego.Rego){rego.Query(query), rego.Runtime(info)} evalArgs := []rego.EvalOption{ rego.EvalRuleIndexing(!params.disableIndexing), rego.EvalEarlyExit(!params.disableEarlyExit), } if len(params.imports.v) > 0 { regoArgs = append(regoArgs, rego.Imports(params.imports.v)) } if params.pkg != "" { regoArgs = append(regoArgs, rego.Package(params.pkg)) } if len(params.dataPaths.v) > 0 { f := loaderFilter{ Ignore: params.ignore, } if params.optimizationLevel <= 0 { regoArgs = append(regoArgs, rego.Load(params.dataPaths.v, f.Apply)) } else { b, err := generateOptimizedBundle(params, false, f.Apply, params.dataPaths.v) if err != nil { return nil, err } regoArgs = append(regoArgs, rego.ParsedBundle("optimized", b)) } } if params.bundlePaths.isFlagSet() { if params.optimizationLevel <= 0 { for _, bundleDir := range params.bundlePaths.v { regoArgs = append(regoArgs, rego.LoadBundle(bundleDir)) } } else { b, err := generateOptimizedBundle(params, true, buildCommandLoaderFilter(true, params.ignore), params.bundlePaths.v) if err != nil { return nil, err } regoArgs = append(regoArgs, rego.ParsedBundle("optimized", b)) } } // skip bundle verification regoArgs = append(regoArgs, rego.SkipBundleVerification(true)) regoArgs = append(regoArgs, rego.Target(params.target.String())) inputBytes, err := readInputBytes(params) if err != nil { return nil, err } if inputBytes != nil { var input interface{} err := util.Unmarshal(inputBytes, &input) if err != nil { return nil, fmt.Errorf("unable to parse input: %s", err.Error()) } inputValue, err := ast.InterfaceToValue(input) if err != nil { return nil, fmt.Errorf("unable to process input: %s", err.Error()) } regoArgs = append(regoArgs, rego.ParsedInput(inputValue)) } // -s {file} (one input schema file) // -s {directory} (one schema directory with input and data schema files) schemaSet, err := loader.Schemas(params.schema.path) if err != nil { return nil, err } regoArgs = append(regoArgs, rego.Schemas(schemaSet)) var tracer *topdown.BufferTracer if params.explain != nil && params.explain.String() != explainModeOff { tracer = topdown.NewBufferTracer() evalArgs = append(evalArgs, rego.EvalQueryTracer(tracer)) if params.target.String() == compile.TargetWasm { fmt.Fprintf(os.Stderr, "warning: explain mode \"%v\" is not supported with wasm target\n", params.explain.String()) } } var m metrics.Metrics if params.metrics { m = metrics.New() // Use the same metrics for preparing and evaluating regoArgs = append(regoArgs, rego.Metrics(m)) evalArgs = append(evalArgs, rego.EvalMetrics(m)) } if params.instrument { regoArgs = append(regoArgs, rego.Instrument(true)) evalArgs = append(evalArgs, rego.EvalInstrument(true)) } rp := resettableProfiler{} if params.profile { rp.p = profiler.New() evalArgs = append(evalArgs, rego.EvalQueryTracer(&rp)) } if params.partial { regoArgs = append(regoArgs, rego.Unknowns(params.unknowns)) } regoArgs = append(regoArgs, rego.DisableInlining(params.disableInlining), rego.ShallowInlining(params.shallowInlining)) var c *cover.Cover if params.coverage { c = cover.New() evalArgs = append(evalArgs, rego.EvalQueryTracer(c)) } if params.strictBuiltinErrors { regoArgs = append(regoArgs, rego.StrictBuiltinErrors(true)) } if params.capabilities != nil { regoArgs = append(regoArgs, rego.Capabilities(params.capabilities.C)) } if params.strict { regoArgs = append(regoArgs, rego.Strict(params.strict)) } evalCtx := &evalContext{ params: params, metrics: m, profiler: &rp, cover: c, tracer: tracer, regoArgs: regoArgs, evalArgs: evalArgs, } return evalCtx, nil } type resettableProfiler struct { p *profiler.Profiler } func (r *resettableProfiler) reset() { r.p = profiler.New() } func (*resettableProfiler) Enabled() bool { return true } func (r *resettableProfiler) TraceEvent(ev topdown.Event) { r.p.TraceEvent(ev) } func (r *resettableProfiler) Config() topdown.TraceConfig { return r.p.Config() } func getProfileSortOrder(sortOrder []string) []string { // convert the sort order slice to a map for faster lookups sortOrderMap := make(map[string]bool) for _, cr := range sortOrder { sortOrderMap[cr] = true } // compare the given sort order and the default for _, cr := range pr.DefaultProfileSortOrder { if _, ok := sortOrderMap[cr]; !ok { sortOrder = append(sortOrder, cr) } } return sortOrder } func readInputBytes(params evalCommandParams) ([]byte, error) { if params.stdinInput { return io.ReadAll(os.Stdin) } else if params.inputPath != "" { path, err := fileurl.Clean(params.inputPath) if err != nil { return nil, err } return os.ReadFile(path) } return nil, nil } const stringType = "string" type repeatedStringFlag struct { v []string isSet bool } func newrepeatedStringFlag(val []string) repeatedStringFlag { return repeatedStringFlag{ v: val, isSet: false, } } func (f *repeatedStringFlag) Type() string { return stringType } func (f *repeatedStringFlag) String() string { return strings.Join(f.v, ",") } func (f *repeatedStringFlag) Set(s string) error { f.v = append(f.v, s) f.isSet = true return nil } func (f *repeatedStringFlag) isFlagSet() bool { return f.isSet } type intFlag struct { v int isSet bool } func newIntFlag(val int) intFlag { return intFlag{ v: val, isSet: false, } } func (f *intFlag) Type() string { return "int" } func (f *intFlag) String() string { return strconv.Itoa(f.v) } func (f *intFlag) Set(s string) error { v, err := strconv.ParseInt(s, 0, 32) f.v = int(v) f.isSet = true return err } func (f *intFlag) isFlagSet() bool { return f.isSet } // resetExprLocations overwrites the row in the location info for every expression contained in pq. // The location on every expression is shallow copied to avoid mutating shared state. Overwriting // the rows ensures that the formatting package does not leave blank lines in between expressions (e.g., // if expression 1 was saved on L10 and expression 2 was saved on L20 then the formatting package would // squash the blank lines.) func resetExprLocations(pq *rego.PartialQueries) { if pq == nil { return } vis := &astLocationResetVisitor{} for i := range pq.Queries { ast.NewGenericVisitor(vis.visit).Walk(pq.Queries[i]) } for i := range pq.Support { ast.NewGenericVisitor(vis.visit).Walk(pq.Support[i]) } } type astLocationResetVisitor struct { n int } func (vis *astLocationResetVisitor) visit(x interface{}) bool { if expr, ok := x.(*ast.Expr); ok { if expr.Location != nil { cpy := *expr.Location cpy.Row = vis.n expr.Location = &cpy } else { expr.Location = location.NewLocation(nil, "", vis.n, 1) } vis.n++ } return false } func generateOptimizedBundle(params evalCommandParams, asBundle bool, filter loader.Filter, paths []string) (*bundle.Bundle, error) { buf := bytes.NewBuffer(nil) var capabilities *ast.Capabilities if params.capabilities.C != nil { capabilities = params.capabilities.C } else { capabilities = ast.CapabilitiesForThisVersion() } compiler := compile.New(). WithCapabilities(capabilities). WithTarget(params.target.String()). WithAsBundle(asBundle). WithOptimizationLevel(params.optimizationLevel). WithOutput(buf). WithEntrypoints(params.entrypoints.v...). WithRegoAnnotationEntrypoints(true). WithPaths(paths...). WithFilter(filter) err := compiler.Build(context.Background()) if err != nil { return nil, err } return compiler.Bundle(), nil }