✨ allow probes to collect their own data from repo clients (ossf#4052)

* introduce independent probe implementations

rather than rely on checks collecting raw data, independent probes
collect their own raw data using the underlying repo client present in
the check request.

Signed-off-by: Spencer Schrock <[email protected]>

* add test

Signed-off-by: Spencer Schrock <[email protected]>

---------

Signed-off-by: Spencer Schrock <[email protected]>

internal/probes/probes.go

@@ -48,13 +48,16 @@ const (
 )
 
 type Probe struct {
-	Name            string
-	Implementation  ProbeImpl
-	RequiredRawData []CheckName
+	Name                      string
+	Implementation            ProbeImpl
+	IndependentImplementation IndependentProbeImpl
+	RequiredRawData           []CheckName
 }
 
 type ProbeImpl func(*checker.RawResults) ([]finding.Finding, string, error)
 
+type IndependentProbeImpl func(*checker.CheckRequest) ([]finding.Finding, string, error)
+
 // registered is the mapping of all registered probes.
 var registered = map[string]Probe{}
 
@@ -69,15 +72,25 @@ func MustRegister(name string, impl ProbeImpl, requiredRawData []CheckName) {
 	}
 }
 
+func MustRegisterIndependent(name string, impl IndependentProbeImpl) {
+	err := register(Probe{
+		Name:                      name,
+		IndependentImplementation: impl,
+	})
+	if err != nil {
+		panic(err)
+	}
+}
+
 func register(p Probe) error {
 	if p.Name == "" {
 		return errors.WithMessage(errors.ErrScorecardInternal, "name cannot be empty")
 	}
-	if p.Implementation == nil {
-		return errors.WithMessage(errors.ErrScorecardInternal, "implementation cannot be nil")
+	if p.Implementation == nil && p.IndependentImplementation == nil {
+		return errors.WithMessage(errors.ErrScorecardInternal, "at least one implementation must be non-nil")
 	}
-	if len(p.RequiredRawData) == 0 {
-		return errors.WithMessage(errors.ErrScorecardInternal, "probes need some raw data")
+	if p.Implementation != nil && len(p.RequiredRawData) == 0 {
+		return errors.WithMessage(errors.ErrScorecardInternal, "non-independent probes need some raw data")
 	}
 	registered[p.Name] = p
 	return nil

internal/probes/probes_test.go

@@ -27,6 +27,10 @@ func emptyImpl(r *checker.RawResults) ([]finding.Finding, string, error) {
 	return nil, "", nil
 }
 
+func emptyIndependentImpl(c *checker.CheckRequest) ([]finding.Finding, string, error) {
+	return nil, "", nil
+}
+
 var (
 	p1 = Probe{
 		Name:            "someProbe1",
@@ -84,6 +88,14 @@ func Test_register(t *testing.T) {
 			},
 			wantErr: false,
 		},
+		{
+			name: "independent probe registration",
+			probe: Probe{
+				Name:                      "bar",
+				IndependentImplementation: emptyIndependentImpl,
+			},
+			wantErr: false,
+		},
 	}
 	for _, tt := range tests {
 		tt := tt

pkg/scorecard.go

@@ -207,7 +207,12 @@ func runEnabledProbes(request *checker.CheckRequest,
 			return fmt.Errorf("getting probe %q: %w", probeName, err)
 		}
 		// Run probe
-		findings, _, err := probe.Implementation(&ret.RawResults)
+		var findings []finding.Finding
+		if probe.IndependentImplementation != nil {
+			findings, _, err = probe.IndependentImplementation(request)
+		} else {
+			findings, _, err = probe.Implementation(&ret.RawResults)
+		}
 		if err != nil {
 			return sce.WithMessage(sce.ErrScorecardInternal, "ending run")
 		}

probes/entries.go

@@ -66,6 +66,9 @@ import (
 // ProbeImpl is the implementation of a probe.
 type ProbeImpl func(*checker.RawResults) ([]finding.Finding, string, error)
 
+// IndependentProbeImpl is the implementation of an independent probe.
+type IndependentProbeImpl func(*checker.CheckRequest) ([]finding.Finding, string, error)
+
 var (
 	// All represents all the probes.
 	All []ProbeImpl
@@ -160,6 +163,9 @@ var (
 		codeReviewOneReviewers.Run,
 		hasBinaryArtifacts.Run,
 	}
+
+	// Probes which don't use pre-computed raw data but rather collect it themselves.
+	Independent = []IndependentProbeImpl{}
 )
 
 //nolint:gochecknoinits