initial public commit

tools/auth/facebook.go

@@ -0,0 +1,51 @@
+package auth
+
+import (
+	"golang.org/x/oauth2"
+)
+
+var _ Provider = (*Facebook)(nil)
+
+// NameFacebook is the unique name of the Facebook provider.
+const NameFacebook string = "facebook"
+
+// Facebook allows authentication via Facebook OAuth2.
+type Facebook struct {
+	*baseProvider
+}
+
+// NewFacebookProvider creates new Facebook provider instance with some defaults.
+func NewFacebookProvider() *Facebook {
+	return &Facebook{&baseProvider{
+		scopes:     []string{"email"},
+		authUrl:    "https://www.facebook.com/dialog/oauth",
+		tokenUrl:   "https://graph.facebook.com/oauth/access_token",
+		userApiUrl: "https://graph.facebook.com/me?fields=name,email,picture.type(large)",
+	}}
+}
+
+// FetchAuthUser returns an AuthUser instance based on the Facebook's user api.
+func (p *Facebook) FetchAuthUser(token *oauth2.Token) (*AuthUser, error) {
+	// https://developers.facebook.com/docs/graph-api/reference/user/
+	rawData := struct {
+		Id      string
+		Name    string
+		Email   string
+		Picture struct {
+			Data struct{ Url string }
+		}
+	}{}
+
+	if err := p.FetchRawUserData(token, &rawData); err != nil {
+		return nil, err
+	}
+
+	user := &AuthUser{
+		Id:        rawData.Id,
+		Name:      rawData.Name,
+		Email:     rawData.Email,
+		AvatarUrl: rawData.Picture.Data.Url,
+	}
+
+	return user, nil
+}