Add support for Fulcio and Rekor, and --sign-by-sigstore=param-file

(skopeo copy) and (skopeo sync) now support --sign-by-sigstore=param-file,
using the containers-sigstore-signing-params.yaml(5) file format.

That notably adds support for Fulcio and Rekor signing.

Signed-off-by: Miloslav Trmač <mitr@redhat.com>

vendor/github.com/go-openapi/analysis/internal/flatten/operations/operations.go

@@ -0,0 +1,90 @@
+package operations
+
+import (
+	"path"
+	"sort"
+	"strings"
+
+	"github.com/go-openapi/jsonpointer"
+	"github.com/go-openapi/spec"
+	"github.com/go-openapi/swag"
+)
+
+// AllOpRefsByRef returns an index of sortable operations
+func AllOpRefsByRef(specDoc Provider, operationIDs []string) map[string]OpRef {
+	return OpRefsByRef(GatherOperations(specDoc, operationIDs))
+}
+
+// OpRefsByRef indexes a map of sortable operations
+func OpRefsByRef(oprefs map[string]OpRef) map[string]OpRef {
+	result := make(map[string]OpRef, len(oprefs))
+	for _, v := range oprefs {
+		result[v.Ref.String()] = v
+	}
+
+	return result
+}
+
+// OpRef is an indexable, sortable operation
+type OpRef struct {
+	Method string
+	Path   string
+	Key    string
+	ID     string
+	Op     *spec.Operation
+	Ref    spec.Ref
+}
+
+// OpRefs is a sortable collection of operations
+type OpRefs []OpRef
+
+func (o OpRefs) Len() int           { return len(o) }
+func (o OpRefs) Swap(i, j int)      { o[i], o[j] = o[j], o[i] }
+func (o OpRefs) Less(i, j int) bool { return o[i].Key < o[j].Key }
+
+// Provider knows how to collect operations from a spec
+type Provider interface {
+	Operations() map[string]map[string]*spec.Operation
+}
+
+// GatherOperations builds a map of sorted operations from a spec
+func GatherOperations(specDoc Provider, operationIDs []string) map[string]OpRef {
+	var oprefs OpRefs
+
+	for method, pathItem := range specDoc.Operations() {
+		for pth, operation := range pathItem {
+			vv := *operation
+			oprefs = append(oprefs, OpRef{
+				Key:    swag.ToGoName(strings.ToLower(method) + " " + pth),
+				Method: method,
+				Path:   pth,
+				ID:     vv.ID,
+				Op:     &vv,
+				Ref:    spec.MustCreateRef("#" + path.Join("/paths", jsonpointer.Escape(pth), method)),
+			})
+		}
+	}
+
+	sort.Sort(oprefs)
+
+	operations := make(map[string]OpRef)
+	for _, opr := range oprefs {
+		nm := opr.ID
+		if nm == "" {
+			nm = opr.Key
+		}
+
+		oo, found := operations[nm]
+		if found && oo.Method != opr.Method && oo.Path != opr.Path {
+			nm = opr.Key
+		}
+
+		if len(operationIDs) == 0 || swag.ContainsStrings(operationIDs, opr.ID) || swag.ContainsStrings(operationIDs, nm) {
+			opr.ID = nm
+			opr.Op.ID = nm
+			operations[nm] = opr
+		}
+	}
+
+	return operations
+}