feat(referrers): API endpoint (#424)

Signed-off-by: Miguel Martinez Trivino <miguel@chainloop.dev>

app/cli/cmd/referrer_discover.go

@@ -0,0 +1,47 @@
+//
+// Copyright 2023 The Chainloop Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package cmd
+
+import (
+	"context"
+
+	"github.com/chainloop-dev/chainloop/app/cli/internal/action"
+	"github.com/spf13/cobra"
+)
+
+func newReferrerDiscoverCmd() *cobra.Command {
+	var digest string
+
+	cmd := &cobra.Command{
+		Use:   "discover",
+		Short: "(Preview) inspect pieces of evidence or artifacts stored through Chainloop",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			res, err := action.NewReferrerDiscover(actionOpts).Run(context.Background(), digest)
+			if err != nil {
+				return err
+			}
+
+			// NOTE: this is a preview/beta command, for now we only return JSON format
+			return encodeJSON(res)
+		},
+	}
+
+	cmd.Flags().StringVarP(&digest, "digest", "d", "", "hash of the attestation, piece of evidence or artifact, i.e sha256:deadbeef")
+	err := cmd.MarkFlagRequired("digest")
+	cobra.CheckErr(err)
+
+	return cmd
+}

app/cli/cmd/root.go

@@ -110,6 +110,7 @@ func NewRootCmd(l zerolog.Logger) *cobra.Command {
 	rootCmd.AddCommand(newWorkflowCmd(), newAuthCmd(), NewVersionCmd(),
 		newAttestationCmd(), newArtifactCmd(), newConfigCmd(),
 		newIntegrationCmd(), newOrganizationCmd(), newCASBackendCmd(),
+		newReferrerDiscoverCmd(),
 	)
 
 	return rootCmd

app/cli/internal/action/referrer_discover.go

@@ -0,0 +1,69 @@
+//
+// Copyright 2023 The Chainloop Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package action
+
+import (
+	"context"
+	"time"
+
+	pb "github.com/chainloop-dev/chainloop/app/controlplane/api/controlplane/v1"
+)
+
+type ReferrerDiscover struct {
+	cfg *ActionsOpts
+}
+
+type ReferrerItem struct {
+	Digest       string          `json:"digest"`
+	Kind         string          `json:"kind"`
+	Downloadable bool            `json:"downloadable"`
+	CreatedAt    *time.Time      `json:"createdAt"`
+	References   []*ReferrerItem `json:"references"`
+}
+
+func NewReferrerDiscover(cfg *ActionsOpts) *ReferrerDiscover {
+	return &ReferrerDiscover{cfg}
+}
+
+func (action *ReferrerDiscover) Run(ctx context.Context, digest string) (*ReferrerItem, error) {
+	client := pb.NewReferrerServiceClient(action.cfg.CPConnection)
+	resp, err := client.Discover(ctx, &pb.ReferrerServiceDiscoverRequest{Digest: digest})
+	if err != nil {
+		return nil, err
+	}
+
+	return pbReferrerItemToAction(resp.Result), nil
+}
+
+func pbReferrerItemToAction(in *pb.ReferrerItem) *ReferrerItem {
+	if in == nil {
+		return nil
+	}
+
+	out := &ReferrerItem{
+		Digest:       in.GetDigest(),
+		Downloadable: in.GetDownloadable(),
+		Kind:         in.GetKind(),
+		CreatedAt:    toTimePtr(in.GetCreatedAt().AsTime()),
+		References:   make([]*ReferrerItem, 0, len(in.GetReferences())),
+	}
+
+	for _, r := range in.GetReferences() {
+		out.References = append(out.References, pbReferrerItemToAction(r))
+	}
+
+	return out
+}