Provide API to set the parameters of Challenge Response Config (#18)

* API to set the Parameters of Challenge Response Config

* Incorporating review comments

* Incorporating review comments

Author: yogeshbdeshpande

verification/challengeresponse.go

@@ -10,6 +10,7 @@ import (
 	"fmt"
 	"log"
 	"net/http"
+	"net/url"
 	"time"
 
 	"github.com/veraison/apiclient/common"
@@ -44,6 +45,60 @@ type ChallengeResponseSession struct {
 	Result   json.RawMessage `json:"result"`
 }
 
+// SetNonce sets the Nonce supplied by the user
+func (cfg *ChallengeResponseConfig) SetNonce(nonce []byte) error {
+	if len(nonce) == 0 {
+		return errors.New("no nonce supplied")
+	}
+	cfg.Nonce = nonce
+	return nil
+}
+
+// SetNonceSz sets the nonce size supplied by the user
+func (cfg *ChallengeResponseConfig) SetNonceSz(nonceSz uint) error {
+	if nonceSz == 0 {
+		return errors.New("zero nonce size supplied")
+	}
+	cfg.NonceSz = nonceSz
+	return nil
+}
+
+// SetEvidenceBuilder sets the Evidence Builder callback supplied by the user
+func (cfg *ChallengeResponseConfig) SetEvidenceBuilder(evidenceBuilder EvidenceBuilder) error {
+	if evidenceBuilder == nil {
+		return errors.New("no evidence builder supplied")
+	}
+	cfg.EvidenceBuilder = evidenceBuilder
+	return nil
+}
+
+// SetSessionURI sets the New Session URI supplied by the user
+func (cfg *ChallengeResponseConfig) SetSessionURI(uri string) error {
+	u, err := url.Parse(uri)
+	if err != nil {
+		return fmt.Errorf("malformed session URI: %w", err)
+	}
+	if !u.IsAbs() {
+		return errors.New("the supplied session URI is not in absolute form")
+	}
+	cfg.NewSessionURI = uri
+	return nil
+}
+
+// SetClient sets the HTTP(s) client connection configuration
+func (cfg *ChallengeResponseConfig) SetClient(client *common.Client) error {
+	if client == nil {
+		return errors.New("no client supplied")
+	}
+	cfg.Client = client
+	return nil
+}
+
+// SetDeleteSession sets the DeleteSession parameter using the supplied val
+func (cfg *ChallengeResponseConfig) SetDeleteSession(val bool) {
+	cfg.DeleteSession = val
+}
+
 // Run implements the challenge-response protocol FSM invoking the user
 // callback. On success, the received Attestation Result is returned.
 func (cfg ChallengeResponseConfig) Run() ([]byte, error) {

verification/challengeresponse_test.go

@@ -15,12 +15,14 @@ import (
 
 var (
 	testNonce    []byte = []byte{0xde, 0xad, 0xbe, 0xef}
+	testNonceSz  uint   = 32
 	testEvidence []byte = []byte{0x0e, 0x0d, 0x0e}
 
 	testBaseURI       = "http://veraison.example"
 	testRelSessionURI = "/challenge-response/v1/session/1"
 	testSessionURI    = testBaseURI + testRelSessionURI
 	testNewSessionURI = testBaseURI + "/challenge-response/v1/newSession"
+	testBadURI        = `http://veraison.example:80challenge-response/v1/session/1`
 )
 
 type testEvidenceBuilder struct{}
@@ -32,6 +34,79 @@ func (testEvidenceBuilder) BuildEvidence(
 	return testEvidence, "application/my-evidence-media-type", nil
 }
 
+func TestChallengeResponseConfig_SetNonce_ok(t *testing.T) {
+	cfg := ChallengeResponseConfig{}
+	err := cfg.SetNonce(testNonce)
+	assert.NoError(t, err)
+}
+
+func TestChallengeResponseConfig_SetNonce_nil_nonce(t *testing.T) {
+	cfg := ChallengeResponseConfig{}
+	expectedErr := `no nonce supplied`
+	var nonce []byte
+	err := cfg.SetNonce(nonce)
+	assert.EqualError(t, err, expectedErr)
+}
+
+func TestChallengeResponseConfig_SetNonceSz_ok(t *testing.T) {
+	cfg := ChallengeResponseConfig{}
+	err := cfg.SetNonceSz(testNonceSz)
+	assert.NoError(t, err)
+}
+
+func TestChallengeResponseConfig_SetNonceSz_zero_noncesz(t *testing.T) {
+	cfg := ChallengeResponseConfig{}
+	expectedErr := `zero nonce size supplied`
+	err := cfg.SetNonceSz(0)
+	assert.EqualError(t, err, expectedErr)
+}
+func TestChallengeResponseConfig_SetClient_ok(t *testing.T) {
+	cfg := ChallengeResponseConfig{}
+	client := common.NewClient()
+	err := cfg.SetClient(client)
+	assert.NoError(t, err)
+}
+
+func TestChallengeResponseConfig_SetClient_nil_client(t *testing.T) {
+	cfg := ChallengeResponseConfig{}
+	expectedErr := `no client supplied`
+	err := cfg.SetClient(nil)
+	assert.EqualError(t, err, expectedErr)
+}
+
+func TestChallengeResponseConfig_SetSessionURI_ok(t *testing.T) {
+	cfg := ChallengeResponseConfig{}
+	err := cfg.SetSessionURI(testSessionURI)
+	assert.NoError(t, err)
+}
+
+func TestChallengeResponseConfig_SetSessionURI_not_absolute(t *testing.T) {
+	cfg := ChallengeResponseConfig{}
+	expectedErr := `the supplied session URI is not in absolute form`
+	err := cfg.SetSessionURI("veraison.example/challenge-response/v1/session/1")
+	assert.EqualError(t, err, expectedErr)
+}
+
+func TestChallengeResponseConfig_SetSessionURI_bad_uri(t *testing.T) {
+	cfg := ChallengeResponseConfig{}
+	expectedErr := `malformed session URI: parse "http://veraison.example:80challenge-response/v1/session/1": invalid port ":80challenge-response" after host`
+	err := cfg.SetSessionURI(testBadURI)
+	assert.EqualError(t, err, expectedErr)
+}
+
+func TestChallengeResponseConfig_SetEvidenceBuilder_ok(t *testing.T) {
+	cfg := ChallengeResponseConfig{}
+	err := cfg.SetEvidenceBuilder(testEvidenceBuilder{})
+	assert.NoError(t, err)
+}
+
+func TestChallengeResponseConfig_SetEvidenceBuilder_no_ok(t *testing.T) {
+	cfg := ChallengeResponseConfig{}
+	expectedErr := `no evidence builder supplied`
+	err := cfg.SetEvidenceBuilder(nil)
+	assert.EqualError(t, err, expectedErr)
+}
+
 func TestChallengeResponseConfig_NewSession_ok(t *testing.T) {
 	newSessionCreatedBody := `
 {