mirror of
https://github.com/hyperledger/fabric-samples.git
synced 2026-06-17 15:35:09 +00:00
Refactor of asset transfer events Go sample for Fabric Gateway (#600)
Split boiler-plate connection code into a separate file since the basic sample already covers this aspect. The `app.go` file now only presents the main application code, making it much easier for readers to view. Also changed the event replay code to use a different style of reading from the real-time eventing example, demonstrating the use of timeouts while reading events we expect to arrive quickly, and avoiding any possibility of the main application execution hanging indefinitely. Signed-off-by: Mark S. Lewis <mark_lewis@uk.ibm.com>
This commit is contained in:
Mark S. Lewis
GitHub
parent
e372006be7
commit
e33943cf4c
5 changed files with 109 additions and 97 deletions
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@ -9,27 +9,15 @@ package main
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import (
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"bytes"
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"context"
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"crypto/x509"
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"encoding/json"
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"errors"
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"fmt"
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"io/ioutil"
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"path"
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"time"
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"github.com/hyperledger/fabric-gateway/pkg/client"
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"github.com/hyperledger/fabric-gateway/pkg/identity"
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"google.golang.org/grpc"
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"google.golang.org/grpc/credentials"
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)
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const (
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mspID = "Org1MSP"
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cryptoPath = "../../test-network/organizations/peerOrganizations/org1.example.com"
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certPath = cryptoPath + "/users/User1@org1.example.com/msp/signcerts/cert.pem"
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keyPath = cryptoPath + "/users/User1@org1.example.com/msp/keystore/"
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tlsCertPath = cryptoPath + "/peers/peer0.org1.example.com/tls/ca.crt"
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peerEndpoint = "localhost:7051"
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gatewayPeer = "peer0.org1.example.com"
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channelName = "mychannel"
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chaincodeName = "events"
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)
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@ -38,19 +26,16 @@ var now = time.Now()
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var assetID = fmt.Sprintf("asset%d", now.Unix()*1e3+int64(now.Nanosecond())/1e6)
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func main() {
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// The gRPC client connection should be shared by all Gateway connections to this endpoint
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clientConnection := newGrpcConnection()
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defer clientConnection.Close()
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id := newIdentity()
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sign := newSign()
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// Create a Gateway connection for a specific client identity
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gateway, err := client.Connect(
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id,
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client.WithSign(sign),
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client.WithClientConnection(clientConnection),
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// Default timeouts for different gRPC calls
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client.WithEvaluateTimeout(5*time.Second),
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client.WithEndorseTimeout(15*time.Second),
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client.WithSubmitTimeout(5*time.Second),
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@ -80,73 +65,6 @@ func main() {
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replayChaincodeEvents(ctx, network, firstBlockNumber)
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}
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// newGrpcConnection creates a gRPC connection to the Gateway server.
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func newGrpcConnection() *grpc.ClientConn {
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certificate, err := loadCertificate(tlsCertPath)
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if err != nil {
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panic(err)
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}
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certPool := x509.NewCertPool()
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certPool.AddCert(certificate)
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transportCredentials := credentials.NewClientTLSFromCert(certPool, gatewayPeer)
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connection, err := grpc.Dial(peerEndpoint, grpc.WithTransportCredentials(transportCredentials))
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if err != nil {
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panic(fmt.Errorf("failed to create gRPC connection: %w", err))
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}
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return connection
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}
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// newIdentity creates a client identity for this Gateway connection using an X.509 certificate.
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func newIdentity() *identity.X509Identity {
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certificate, err := loadCertificate(certPath)
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if err != nil {
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panic(err)
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}
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id, err := identity.NewX509Identity(mspID, certificate)
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if err != nil {
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panic(err)
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}
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return id
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}
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func loadCertificate(filename string) (*x509.Certificate, error) {
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certificatePEM, err := ioutil.ReadFile(filename)
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if err != nil {
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return nil, fmt.Errorf("failed to read certificate file: %w", err)
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}
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return identity.CertificateFromPEM(certificatePEM)
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}
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// newSign creates a function that generates a digital signature from a message digest using a private key.
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func newSign() identity.Sign {
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files, err := ioutil.ReadDir(keyPath)
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if err != nil {
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panic(fmt.Errorf("failed to read private key directory: %w", err))
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}
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privateKeyPEM, err := ioutil.ReadFile(path.Join(keyPath, files[0].Name()))
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if err != nil {
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panic(fmt.Errorf("failed to read private key file: %w", err))
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}
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privateKey, err := identity.PrivateKeyFromPEM(privateKeyPEM)
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if err != nil {
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panic(err)
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}
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sign, err := identity.NewPrivateKeySign(privateKey)
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if err != nil {
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panic(err)
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}
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return sign
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}
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func startChaincodeEventListening(ctx context.Context, network *client.Network) {
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fmt.Printf("\n*** Start chaincode event listening\n")
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@ -234,12 +152,18 @@ func replayChaincodeEvents(ctx context.Context, network *client.Network, startBl
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panic(fmt.Errorf("failed to start chaincode event listening: %w", err))
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}
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for event := range events {
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asset := formatJSON(event.Payload)
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fmt.Printf("\n<-- Chaincode event replayed: %s - %s\n", event.EventName, asset)
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for {
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select {
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case <-time.After(10 * time.Second):
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panic(errors.New("timeout waiting for event replay"))
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if event.EventName == "DeleteAsset" {
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break
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case event := <-events:
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asset := formatJSON(event.Payload)
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fmt.Printf("\n<-- Chaincode event replayed: %s - %s\n", event.EventName, asset)
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if event.EventName == "DeleteAsset" {
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return
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}
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}
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}
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}
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95
asset-transfer-events/application-gateway-go/connect.go
Executable file
95
asset-transfer-events/application-gateway-go/connect.go
Executable file
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@ -0,0 +1,95 @@
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/*
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Copyright 2022 IBM All Rights Reserved.
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SPDX-License-Identifier: Apache-2.0
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*/
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package main
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import (
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"crypto/x509"
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"fmt"
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"io/ioutil"
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"path"
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"github.com/hyperledger/fabric-gateway/pkg/identity"
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"google.golang.org/grpc"
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"google.golang.org/grpc/credentials"
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)
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const (
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mspID = "Org1MSP"
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cryptoPath = "../../test-network/organizations/peerOrganizations/org1.example.com"
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certPath = cryptoPath + "/users/User1@org1.example.com/msp/signcerts/cert.pem"
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keyPath = cryptoPath + "/users/User1@org1.example.com/msp/keystore/"
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tlsCertPath = cryptoPath + "/peers/peer0.org1.example.com/tls/ca.crt"
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peerEndpoint = "localhost:7051"
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gatewayPeer = "peer0.org1.example.com"
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)
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// newGrpcConnection creates a gRPC connection to the Gateway server.
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func newGrpcConnection() *grpc.ClientConn {
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certificate, err := loadCertificate(tlsCertPath)
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if err != nil {
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panic(err)
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}
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certPool := x509.NewCertPool()
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certPool.AddCert(certificate)
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transportCredentials := credentials.NewClientTLSFromCert(certPool, gatewayPeer)
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connection, err := grpc.Dial(peerEndpoint, grpc.WithTransportCredentials(transportCredentials))
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if err != nil {
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panic(fmt.Errorf("failed to create gRPC connection: %w", err))
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}
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return connection
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}
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// newIdentity creates a client identity for this Gateway connection using an X.509 certificate.
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func newIdentity() *identity.X509Identity {
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certificate, err := loadCertificate(certPath)
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if err != nil {
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panic(err)
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}
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id, err := identity.NewX509Identity(mspID, certificate)
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if err != nil {
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panic(err)
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}
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return id
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}
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func loadCertificate(filename string) (*x509.Certificate, error) {
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certificatePEM, err := ioutil.ReadFile(filename)
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if err != nil {
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return nil, fmt.Errorf("failed to read certificate file: %w", err)
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}
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return identity.CertificateFromPEM(certificatePEM)
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}
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// newSign creates a function that generates a digital signature from a message digest using a private key.
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func newSign() identity.Sign {
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files, err := ioutil.ReadDir(keyPath)
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if err != nil {
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panic(fmt.Errorf("failed to read private key directory: %w", err))
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}
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privateKeyPEM, err := ioutil.ReadFile(path.Join(keyPath, files[0].Name()))
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if err != nil {
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panic(fmt.Errorf("failed to read private key file: %w", err))
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}
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privateKey, err := identity.PrivateKeyFromPEM(privateKeyPEM)
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if err != nil {
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panic(err)
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}
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sign, err := identity.NewPrivateKeySign(privateKey)
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if err != nil {
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panic(err)
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}
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return sign
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}
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@ -4,7 +4,7 @@ go 1.16
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require (
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github.com/hyperledger/fabric-gateway v1.0.0
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github.com/hyperledger/fabric-protos-go v0.0.0-20220125190318-19041b215616
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github.com/hyperledger/fabric-protos-go v0.0.0-20220125190318-19041b215616 // indirect
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github.com/miekg/pkcs11 v1.1.1 // indirect
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golang.org/x/net v0.0.0-20220121210141-e204ce36a2ba // indirect
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golang.org/x/sys v0.0.0-20220114195835-da31bd327af9 // indirect
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@ -165,7 +165,6 @@ github.com/hyperledger/fabric-amcl v0.0.0-20200424173818-327c9e2cf77a h1:JAKZdGu
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github.com/hyperledger/fabric-amcl v0.0.0-20200424173818-327c9e2cf77a/go.mod h1:X+DIyUsaTmalOpmpQfIvFZjKHQedrURQ5t4YqquX7lE=
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github.com/hyperledger/fabric-gateway v1.0.0 h1:bki1JYYdQzRGHFArxtgG4wyH6sbFNbYn3PzpdeDfjdk=
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github.com/hyperledger/fabric-gateway v1.0.0/go.mod h1:uaRZyC+xzfucPqZIJpesdEsugVvChPhDxZiZmDRSFd4=
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github.com/hyperledger/fabric-protos-go v0.0.0-20211118165945-23d738fc3553 h1:E9f0v1q4EDfrE+0LdkxVtdYKAZ7PGCaj1bBx45R9yEQ=
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github.com/hyperledger/fabric-protos-go v0.0.0-20211118165945-23d738fc3553/go.mod h1:xVYTjK4DtZRBxZ2D9aE4y6AbLaPwue2o/criQyQbVD0=
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github.com/hyperledger/fabric-protos-go v0.0.0-20220125190318-19041b215616 h1:CZrcDuLxBorn/xvbQl/r9kC0pniDEm0GuiBn9GgfY3c=
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github.com/hyperledger/fabric-protos-go v0.0.0-20220125190318-19041b215616/go.mod h1:xVYTjK4DtZRBxZ2D9aE4y6AbLaPwue2o/criQyQbVD0=
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@ -194,7 +193,6 @@ github.com/mattn/go-colorable v0.0.9/go.mod h1:9vuHe8Xs5qXnSaW/c/ABM9alt+Vo+STaO
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github.com/mattn/go-isatty v0.0.3/go.mod h1:M+lRXTBqGeGNdLjl/ufCoiOlB5xdOkqRJdNxMWT7Zi4=
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github.com/matttproud/golang_protobuf_extensions v1.0.1/go.mod h1:D8He9yQNgCq6Z5Ld7szi9bcBfOoFv/3dc6xSMkL2PC0=
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github.com/miekg/dns v1.0.14/go.mod h1:W1PPwlIAgtquWBMBEV9nkV9Cazfe8ScdGz/Lj7v3Nrg=
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github.com/miekg/pkcs11 v1.0.3 h1:iMwmD7I5225wv84WxIG/bmxz9AXjWvTWIbM/TYHvWtw=
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github.com/miekg/pkcs11 v1.0.3/go.mod h1:XsNlhZGX73bx86s2hdc/FuaLm2CPZJemRLMA+WTFxgs=
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github.com/miekg/pkcs11 v1.1.1 h1:Ugu9pdy6vAYku5DEpVWVFPYnzV+bxB+iRdbuFSu7TvU=
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github.com/miekg/pkcs11 v1.1.1/go.mod h1:XsNlhZGX73bx86s2hdc/FuaLm2CPZJemRLMA+WTFxgs=
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@ -342,7 +340,6 @@ golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLL
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golang.org/x/net v0.0.0-20200822124328-c89045814202/go.mod h1:/O7V0waA8r7cgGh81Ro3o1hOxt32SMVPicZroKQ2sZA=
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golang.org/x/net v0.0.0-20200904194848-62affa334b73/go.mod h1:/O7V0waA8r7cgGh81Ro3o1hOxt32SMVPicZroKQ2sZA=
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golang.org/x/net v0.0.0-20210405180319-a5a99cb37ef4/go.mod h1:p54w0d4576C0XHj96bSt6lcn1PtDYWL6XObtHCRCNQM=
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golang.org/x/net v0.0.0-20210805182204-aaa1db679c0d h1:20cMwl2fHAzkJMEA+8J4JgqBQcQGzbisXo31MIeenXI=
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golang.org/x/net v0.0.0-20210805182204-aaa1db679c0d/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
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golang.org/x/net v0.0.0-20220121210141-e204ce36a2ba h1:6u6sik+bn/y7vILcYkK3iwTBWN7WtBvB0+SZswQnbf8=
|
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golang.org/x/net v0.0.0-20220121210141-e204ce36a2ba/go.mod h1:CfG3xpIq0wQ8r1q4Su4UZFWDARRcnwPjda9FqA0JpMk=
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|
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@ -376,7 +373,6 @@ golang.org/x/sys v0.0.0-20210330210617-4fbd30eecc44/go.mod h1:h1NjWce9XRLGQEsW7w
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golang.org/x/sys v0.0.0-20210423082822-04245dca01da/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
|
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golang.org/x/sys v0.0.0-20210510120138-977fb7262007/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
|
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golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
|
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golang.org/x/sys v0.0.0-20211110154304-99a53858aa08 h1:WecRHqgE09JBkh/584XIE6PMz5KKE/vER4izNUi30AQ=
|
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golang.org/x/sys v0.0.0-20211110154304-99a53858aa08/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
|
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golang.org/x/sys v0.0.0-20211216021012-1d35b9e2eb4e/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
|
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golang.org/x/sys v0.0.0-20220114195835-da31bd327af9 h1:XfKQ4OlFl8okEOr5UvAqFRVj8pY/4yfcXrddB8qAbU0=
|
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@ -388,7 +384,6 @@ golang.org/x/text v0.3.1-0.20180807135948-17ff2d5776d2/go.mod h1:NqM8EUOU14njkJ3
|
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golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=
|
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golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
|
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golang.org/x/text v0.3.5/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
|
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golang.org/x/text v0.3.6 h1:aRYxNxv6iGQlyVaZmk6ZgYEDa+Jg18DxebPSrd6bg1M=
|
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golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
|
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golang.org/x/text v0.3.7 h1:olpwvP2KacW1ZWvsR7uQhoyTYvKAupfQrRGBFM352Gk=
|
||||
golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
|
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|
|
@ -440,7 +435,6 @@ google.golang.org/genproto v0.0.0-20190819201941-24fa4b261c55/go.mod h1:DMBHOl98
|
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google.golang.org/genproto v0.0.0-20190911173649-1774047e7e51/go.mod h1:IbNlFCBrqXvoKpeg0TB2l7cyZUmoaFKYIwrEpbDKLA8=
|
||||
google.golang.org/genproto v0.0.0-20191108220845-16a3f7862a1a/go.mod h1:n3cpQtvxv34hfy77yVDNjmbRyujviMdxYliBSkLhpCc=
|
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google.golang.org/genproto v0.0.0-20200513103714-09dca8ec2884/go.mod h1:55QSHmfGQM9UVYDPBsyGGes0y52j32PQ3BqQfXhyH3c=
|
||||
google.golang.org/genproto v0.0.0-20200526211855-cb27e3aa2013 h1:+kGHl1aib/qcwaRi1CbqBZ1rk19r85MNUf8HaBghugY=
|
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google.golang.org/genproto v0.0.0-20200526211855-cb27e3aa2013/go.mod h1:NbSheEEYHJ7i3ixzK3sjbqSGDJWnxyFXZblF3eUsNvo=
|
||||
google.golang.org/genproto v0.0.0-20220118154757-00ab72f36ad5 h1:zzNejm+EgrbLfDZ6lu9Uud2IVvHySPl8vQzf04laR5Q=
|
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google.golang.org/genproto v0.0.0-20220118154757-00ab72f36ad5/go.mod h1:5CzLGKJ67TSI2B9POpiiyGha0AjJvZIUgRMt1dSmuhc=
|
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@ -453,7 +447,6 @@ google.golang.org/grpc v1.27.0/go.mod h1:qbnxyOmOxrQa7FizSgH+ReBfzJrCY1pSN7KXBS8
|
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google.golang.org/grpc v1.33.1/go.mod h1:fr5YgcSWrqhRRxogOsw7RzIpsmvOZ6IcH4kBYTpR3n0=
|
||||
google.golang.org/grpc v1.36.0/go.mod h1:qjiiYl8FncCW8feJPdyg3v6XW24KsRHe+dy9BAGRRjU=
|
||||
google.golang.org/grpc v1.40.0/go.mod h1:ogyxbiOoUXAkP+4+xa6PZSE9DZgIHtSpzjDTB9KAK34=
|
||||
google.golang.org/grpc v1.42.0 h1:XT2/MFpuPFsEX2fWh3YQtHkZ+WYZFQRfaUgLZYj/p6A=
|
||||
google.golang.org/grpc v1.42.0/go.mod h1:k+4IHHFw41K8+bbowsex27ge2rCb65oeWqe4jJ590SU=
|
||||
google.golang.org/grpc v1.44.0 h1:weqSxi/TMs1SqFRMHCtBgXRs8k3X39QIDEZ0pRcttUg=
|
||||
google.golang.org/grpc v1.44.0/go.mod h1:k+4IHHFw41K8+bbowsex27ge2rCb65oeWqe4jJ590SU=
|
||||
|
|
|
|||
|
|
@ -39,7 +39,7 @@ rm -R ../asset-transfer-events/application-javascript/wallet
|
|||
createNetwork
|
||||
print "Initializing Go gateway application"
|
||||
pushd ../asset-transfer-events/application-gateway-go
|
||||
print "Executing AssetTransferEvents.go"
|
||||
print "Executing application"
|
||||
go run .
|
||||
popd
|
||||
stopNetwork
|
||||
|
|
|
|||
Loading…
Reference in a new issue