Can fetch a token based on the device code

internal/login/login.go

@@ -20,6 +20,10 @@ type DeviceAuthorization struct {
 	VerificationURI string `json:"verificationUri"`
 }
 
+type DeviceAuthorizationToken struct {
+	AccessToken string `json:"accessToken"`
+}
+
 type UnauthenticatedClient interface {
 	MakeRequest(
 		method string,
@@ -96,6 +100,32 @@ func FetchDeviceAuthorization(
 	return deviceAuthorization, nil
 }
 
+func FetchToken(
+	client UnauthenticatedClient,
+	deviceCode string,
+	baseURI string,
+) (DeviceAuthorizationToken, error) {
+	path := fmt.Sprintf("%s/internal/device-authorization/token", baseURI)
+	body := fmt.Sprintf(
+		`{
+			"deviceCode": %q
+		}`,
+		deviceCode,
+	)
+	res, err := client.MakeRequest("POST", path, []byte(body))
+	if err != nil {
+		return DeviceAuthorizationToken{}, err
+	}
+
+	var deviceAuthorizationToken DeviceAuthorizationToken
+	err = json.Unmarshal(res, &deviceAuthorizationToken)
+	if err != nil {
+		return DeviceAuthorizationToken{}, err
+	}
+
+	return deviceAuthorizationToken, nil
+}
+
 func GetDeviceName() string {
 	deviceName, err := os.Hostname()
 	if err != nil {

internal/login/login_test.go

@@ -22,7 +22,7 @@ func (c *mockClient) MakeRequest(
 ) ([]byte, error) {
 	args := c.Called(method, path, data)
 
-	return data, args.Error(1)
+	return args.Get(0).([]byte), args.Error(1)
 }
 
 func TestFetchDeviceAuthorization(t *testing.T) {
@@ -38,11 +38,17 @@ func TestFetchDeviceAuthorization(t *testing.T) {
 		}`),
 	).Return([]byte(`{
 		"deviceCode": "test-device-code",
-		"expiresIn": 0000000001,
+		"expiresIn": 1,
 		"userCode": "0001",
 		"verificationUri": "/confirm-auth/test-device-code"
 	}`), nil)
-	expected := login.DeviceAuthorization{}
+	expected := login.DeviceAuthorization{
+		DeviceCode:      "test-device-code",
+		ExpiresIn:       1,
+		UserCode:        "0001",
+		VerificationURI: "/confirm-auth/test-device-code",
+	}
+
 	result, err := login.FetchDeviceAuthorization(
 		&mockClient,
 		"test-client-id",
@@ -53,3 +59,30 @@ func TestFetchDeviceAuthorization(t *testing.T) {
 	require.NoError(t, err)
 	assert.Equal(t, expected, result)
 }
+
+func TestFetchToken(t *testing.T) {
+	baseURI := "http://test.com"
+	mockClient := mockClient{}
+	mockClient.On(
+		"MakeRequest",
+		"POST",
+		"http://test.com/internal/device-authorization/token",
+		[]byte(`{
+			"deviceCode": "test-device-code"
+		}`),
+	).Return([]byte(`{
+		"accessToken": "test-access-token"
+	}`), nil)
+	expected := login.DeviceAuthorizationToken{
+		AccessToken: "test-access-token",
+	}
+
+	result, err := login.FetchToken(
+		&mockClient,
+		"test-device-code",
+		baseURI,
+	)
+
+	require.NoError(t, err)
+	assert.Equal(t, expected, result)
+}