[c] Persist contract signatures to a JSON file

- Signatures are written to a file called `$email-$contractUUID.proof`
- Close connection client-side
- Preserve peer connections

dfssc/sign.go

@@ -54,5 +54,13 @@ func signContract(args []string) {
 		fmt.Fprintln(os.Stderr, err)
 		os.Exit(5)
 	}
+
 	// Persist evidencies, if any
+	err = manager.PersistSignaturesToFile()
+	if err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(5)
+	}
+
+	fmt.Println("Signature complete ! See .proof file for evidences.")
 }

dfssc/sign/create_test.go

 package sign
 
-/*
 import (
 	"fmt"
 	"io/ioutil"
@@ -59,4 +58,3 @@ func TestComputeFile(t *testing.T) {
 	assert.Equal(t, "37fd29decfb2d689439478b1f64b60441534c1e373a7023676c94ac6772639edab46f80139d167a2741f159e62b3064eca58bb331d32cd10770f29064af2a9de", fmt.Sprintf("%x", m.hash))
 	assert.Equal(t, "contract.txt", m.filename)
 }
-*/

dfssc/sign/persist.go

+package sign
+
+import (
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+
+	cAPI "dfss/dfssc/api"
+	"dfss/dfssp/contract"
+)
+
+// SignedContractJSON is an union of contract and realted signatures
+type SignedContractJSON struct {
+	Contract   contract.JSON
+	Signatures []cAPI.Signature
+}
+
+// PersistSignaturesToFile save contract informations and signatures to disk
+func (m *SignatureManager) PersistSignaturesToFile() error {
+
+	// Check content, don't write an empty file
+	if len(m.archives.recievedSignatures) == 0 {
+		return fmt.Errorf("No stored signatures, cannot create an empty file (yes I'm a coward)")
+	}
+
+	// Fill JSON struct
+	signedContract := SignedContractJSON{
+		Contract: *m.contract,
+		Signatures: make(
+			[]cAPI.Signature,
+			len(m.archives.sentSignatures)+len(m.archives.recievedSignatures),
+		),
+	}
+
+	for i, s := range m.archives.sentSignatures {
+		signedContract.Signatures[i] = *s
+	}
+
+	for i, s := range m.archives.recievedSignatures {
+		signedContract.Signatures[len(m.archives.sentSignatures)+i] = *s
+	}
+
+	proof, err := json.MarshalIndent(signedContract, "", " ")
+	if err != nil {
+		return err
+	}
+
+	return ioutil.WriteFile(m.mail+"-"+m.contract.UUID+".proof", proof, 0600)
+}

dfssc/sign/protocol.go

@@ -66,6 +66,13 @@ func (m *SignatureManager) Sign() error {
 
 	dAPI.DLog("{" + fmt.Sprintf("%d", myID) + "} Exit signature round")
 
+	// Network's job is done, cleaning time
+	// Shutdown and platform client and TODO peer server & connections
+	err = m.platformConn.Close()
+	if err != nil {
+		return err
+	}
+
 	return nil
 }
 
@@ -144,3 +151,16 @@ func (m *SignatureManager) promiseRound(pendingSet, sendSet []uint32, myID uint3
 		}
 	}
 }
+
+// closeAllPeerClient tries to close all established connection with other peers
+func (m *SignatureManager) closeAllPeerClient() {
+	for k, client := range m.peersConn {
+		err := client.Close()
+		if err != nil {
+			// We don't care
+		}
+		// Remove associated grpc client
+		delete(m.peers, k)
+		fmt.Println("- Close connection to " + k)
+	}
+}

dfssc/sign/starter.go

@@ -24,6 +24,8 @@ type SignatureManager struct {
 	localPort    int
 	contract     *contract.JSON // contains the contractUUID, the list of the signers' hashes, the hash of the contract
 	platform     pAPI.PlatformClient
+	platformConn *grpc.ClientConn
+	peersConn    map[string]*grpc.ClientConn
 	peers        map[string]*cAPI.ClientClient
 	hashToID     map[string]uint32
 	nbReady      int
@@ -75,7 +77,9 @@ func NewSignatureManager(fileCA, fileCert, fileKey, addrPort, passphrase string,
 	}
 
 	m.platform = pAPI.NewPlatformClient(conn)
+	m.platformConn = conn
 
+	m.peersConn = make(map[string]*grpc.ClientConn)
 	m.peers = make(map[string]*cAPI.ClientClient)
 	for _, u := range c.Signers {
 		if u.Email != m.auth.Cert.Subject.CommonName {
@@ -139,6 +143,9 @@ func (m *SignatureManager) addPeer(user *pAPI.User) (ready bool, err error) {
 	client := cAPI.NewClientClient(conn)
 	lastConnection := m.peers[user.Email]
 	m.peers[user.Email] = &client
+	// The connection is encapsulated into the interface, so we
+	// need to create another way to access it
+	m.peersConn[user.Email] = conn
 
 	ctx, cancel := context.WithTimeout(context.Background(), time.Minute)
 	defer cancel()

tests/sign_test.go

@@ -14,6 +14,17 @@ import (
 	"github.com/bmizerany/assert"
 )
 
+// TestSignContract unroll the whole signature process.
+//
+// GOOD CASE
+// - Start platform
+// - Register client1, client2 and client3
+// - Create contract `contract.txt`
+// - Sign it
+// - Check if all proof files are present
+//
+// TODO BAD CASES
+
 func TestSignContract(t *testing.T) {
 	// Cleanup
 	eraseDatabase()
@@ -101,4 +112,20 @@ func TestSignContract(t *testing.T) {
 			assert.T(t, r.Match(output), "Regex is not satisfied: ", r.String())
 		}
 	}
+
+	// Ensure that all the files are present
+	proofFile := regexp.MustCompile(`client[0-9]+@example.com.*\.proof`)
+	files, _ := ioutil.ReadDir("./")
+
+	matches := 0
+	for _, file := range files {
+		if proofFile.Match([]byte(file.Name())) {
+			matches++
+			err = os.Remove("./" + file.Name())
+			assert.T(t, err == nil, "Cannot remove .proof matching file")
+		}
+	}
+	assert.T(t, matches == 3, "Missing proof file ?")
+
+	time.Sleep(time.Second)
 }