Add -O json option to calculatepackageid

Signed-off-by: Tatsuya Sato <tatsuya.sato.so@hitachi.com>

internal/peer/lifecycle/chaincode/calculatepackageid.go

@@ -7,9 +7,11 @@ SPDX-License-Identifier: Apache-2.0
 package chaincode
 
 import (
+	"encoding/json"
 	"fmt"
 	"io"
 	"os"
+	"strings"
 
 	"github.com/hyperledger/fabric/core/chaincode/persistence"
 	"github.com/pkg/errors"
@@ -28,7 +30,13 @@ type PackageIDCalculator struct {
 // CalculatePackageIDInput holds the input parameters for calculating
 // the package ID of a packaged chaincode
 type CalculatePackageIDInput struct {
-	PackageFile string
+	PackageFile  string
+	OutputFormat string
+}
+
+// CalculatePackageIDOutput holds the JSON output format
+type CalculatePackageIDOutput struct {
+	PackageID string `json:"package_id"`
 }
 
 // Validate checks that the required parameters are provided
@@ -64,6 +72,7 @@ func CalculatePackageIDCmd(p *PackageIDCalculator) *cobra.Command {
 		"peerAddresses",
 		"tlsRootCertFiles",
 		"connectionProfile",
+		"output",
 	}
 	attachFlags(calculatePackageIDCmd, flagList)
 
@@ -103,12 +112,25 @@ func (p *PackageIDCalculator) PackageID() error {
 
 	packageID := persistence.PackageID(metadata.Label, pkgBytes)
 
+	if strings.ToLower(p.Input.OutputFormat) == "json" {
+		output := CalculatePackageIDOutput{
+			PackageID: packageID,
+		}
+		outputJson, err := json.MarshalIndent(&output, "", "\t")
+		if err != nil {
+			return errors.WithMessage(err, "failed to marshal output")
+		}
+		fmt.Fprintf(p.Writer, "%s\n", string(outputJson))
+		return nil
+	}
+
 	fmt.Fprintf(p.Writer, "%s\n", packageID)
 	return nil
 }
 
 func (p *PackageIDCalculator) setInput(packageFile string) {
 	p.Input = &CalculatePackageIDInput{
-		PackageFile: packageFile,
+		PackageFile:  packageFile,
+		OutputFormat: output,
 	}
 }

internal/peer/lifecycle/chaincode/calculatepackageid_test.go

@@ -7,6 +7,8 @@ SPDX-License-Identifier: Apache-2.0
 package chaincode_test
 
 import (
+	"encoding/json"
+	"fmt"
 	"io/ioutil"
 
 	"github.com/hyperledger/fabric/internal/peer/lifecycle/chaincode"
@@ -86,6 +88,23 @@ var _ = Describe("CalculatePackageID", func() {
 				Expect(err).To(MatchError(ContainSubstring("could not parse as a chaincode install package")))
 			})
 		})
+
+		Context("when JSON-formatted output is requested", func() {
+			BeforeEach(func() {
+				packageIDCalculator.Input.OutputFormat = "json"
+			})
+
+			It("calculates the package IDs for chaincodes and writes the output as JSON", func() {
+				err := packageIDCalculator.PackageID()
+				Expect(err).NotTo(HaveOccurred())
+				expectedOutput := &chaincode.CalculatePackageIDOutput{
+					PackageID: "Real-Label:fb3edf9621c5e3d864079d8c9764205f4db09d7021cfa4124aa79f4edcc2f64a",
+				}
+				json, err := json.MarshalIndent(expectedOutput, "", "\t")
+				Expect(err).NotTo(HaveOccurred())
+				Eventually(packageIDCalculator.Writer).Should(gbytes.Say(fmt.Sprintf(`\Q%s\E`, string(json))))
+			})
+		})
 	})
 
 	Describe("CalculatePackageIDCmd", func() {