update LinkedIn connector to use v2 APIs

This updates LinkedIn connector to use the more recent v2 APIs. Necessary because v1 APIs are not able to retrieve email ids any more with the default permissions.

The API URLs are now different. Fetching the email address is now a separate call, made after fetching the profile details. The `r_basicprofile` permission is not needed any more, and `r_liteprofile` (which seems to be the one assigned by default) is sufficient.

The relevant API specifications are at:
- https://docs.microsoft.com/en-us/linkedin/shared/integrations/people/profile-api
- https://docs.microsoft.com/en-us/linkedin/shared/integrations/people/primary-contact-api
- https://docs.microsoft.com/en-us/linkedin/consumer/integrations/self-serve/migration-faq#how-do-i-retrieve-the-members-email-address

connector/linkedin/linkedin.go

@@ -16,7 +16,7 @@ import (
 )
 
 const (
-	apiURL   = "https://api.linkedin.com/v1"
+	apiURL   = "https://api.linkedin.com/v2"
 	authURL  = "https://www.linkedin.com/oauth/v2/authorization"
 	tokenURL = "https://www.linkedin.com/oauth/v2/accessToken"
 )
@@ -38,7 +38,7 @@ func (c *Config) Open(id string, logger log.Logger) (connector.Connector, error)
 				AuthURL:  authURL,
 				TokenURL: tokenURL,
 			},
-			Scopes:      []string{"r_basicprofile", "r_emailaddress"},
+			Scopes:      []string{"r_liteprofile", "r_emailaddress"},
 			RedirectURL: c.RedirectURI,
 		},
 		logger: logger,
@@ -133,11 +133,19 @@ func (c *linkedInConnector) Refresh(ctx context.Context, s connector.Scopes, ide
 
 type profile struct {
 	ID        string `json:"id"`
-	FirstName string `json:"firstName"`
-	LastName  string `json:"lastName"`
+	FirstName string `json:"localizedFirstName"`
+	LastName  string `json:"localizedLastName"`
 	Email     string `json:"emailAddress"`
 }
 
+type emailresp struct {
+	Elements []struct {
+		Handle struct {
+			EmailAddress string `json:"emailAddress"`
+		} `json:"handle~"`
+	} `json:"elements"`
+}
+
 // fullname returns a full name of a person, or email if the resulting name is
 // empty
 func (p profile) fullname() string {
@@ -149,15 +157,50 @@ func (p profile) fullname() string {
 	return fname
 }
 
+func (c *linkedInConnector) primaryEmail(ctx context.Context, client *http.Client) (email string, err error) {
+	req, err := http.NewRequest("GET", apiURL+"/emailAddress?q=members&projection=(elements*(handle~))", nil)
+	if err != nil {
+		return email, fmt.Errorf("new req: %v", err)
+	}
+
+	resp, err := client.Do(req.WithContext(ctx))
+	if err != nil {
+		return email, fmt.Errorf("get URL %v", err)
+	}
+	defer resp.Body.Close()
+
+	body, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return email, fmt.Errorf("read body: %v", err)
+	}
+
+	if resp.StatusCode != http.StatusOK {
+		return email, fmt.Errorf("%s: %s", resp.Status, body)
+	}
+
+	var parsedResp emailresp
+	err = json.Unmarshal(body, &parsedResp)
+	if err == nil {
+		for _, elem := range parsedResp.Elements {
+			email = elem.Handle.EmailAddress
+		}
+	}
+
+	if email == "" {
+		err = fmt.Errorf("email is not set")
+	}
+
+	return email, err
+}
+
 func (c *linkedInConnector) profile(ctx context.Context, client *http.Client) (p profile, err error) {
-	// https://developer.linkedin.com/docs/fields/basic-profile
-	req, err := http.NewRequest("GET", apiURL+"/people/~:(id,first-name,last-name,email-address)", nil)
+	// https://docs.microsoft.com/en-us/linkedin/shared/integrations/people/profile-api
+	// https://docs.microsoft.com/en-us/linkedin/shared/integrations/people/primary-contact-api
+	// https://docs.microsoft.com/en-us/linkedin/consumer/integrations/self-serve/migration-faq#how-do-i-retrieve-the-members-email-address
+	req, err := http.NewRequest("GET", apiURL+"/me", nil)
 	if err != nil {
 		return p, fmt.Errorf("new req: %v", err)
 	}
-	q := req.URL.Query()
-	q.Add("format", "json")
-	req.URL.RawQuery = q.Encode()
 
 	resp, err := client.Do(req.WithContext(ctx))
 	if err != nil {
@@ -177,9 +220,11 @@ func (c *linkedInConnector) profile(ctx context.Context, client *http.Client) (p
 		return p, fmt.Errorf("JSON decode: %v", err)
 	}
 
-	if p.Email == "" {
-		return p, fmt.Errorf("email is not set")
+	email, err := c.primaryEmail(ctx, client)
+	if err != nil {
+		return p, fmt.Errorf("fetching email: %v", err)
 	}
+	p.Email = email
 
 	return p, err
 }