Add Auth0 JWT support

.dockerignore

@@ -2,3 +2,4 @@ example
 tmp
 *.md
 web/build
+docker-compose.*

README.md

@@ -234,7 +234,7 @@ auth:
 #   type: jwt
 #   cookie: _app_session
 #   secret: abc335bfcfdb04e50db5bb0a4d67ab9
-#   public_key_file: abc335bfcfdb04e50db5bb0a4d67ab9
+#   public_key_file: /secrets/public_key.pem
 #   public_key_type: ecdsa #rsa
 
 database:
@@ -283,10 +283,44 @@ SG_AUTH_URL
 SG_AUTH_PASSWORD
 ```
 
+## Authentication
+
+You can only have one type of authentication enabled. You can either pick Rails or JWT. Uncomment the one you use and leave the rest commented out.
+
+#### JWT Tokens
+
+```yaml
+auth:
+  type: jwt
+  provider: auth0 #none
+  cookie: _app_session
+  secret: abc335bfcfdb04e50db5bb0a4d67ab9
+  public_key_file: /secrets/public_key.pem
+  public_key_type: ecdsa #rsa
+```
+
+For JWT tokens we currently support tokens from a provider like Auth0
+or if you have a custom solution then we look for the `user_id` in the
+`subject` claim of of the `id token`. If you pick Auth0 then we derive two variables from the token `user_id` and `user_id_provider` for to use in your filters.
+
+We can get the JWT token either from the `authorization` header where we expect it to be a `bearer` token or if `cookie` is specified then we look there.
+
+For verified either a `secret` or a public key (ecdsa or rsa) is required. When using public keys they have to be in a PEM format file.
+
 ## Deployment
 
-How do I deploy the Super Graph service with my existing rails app? You have several options here. Esentially you need to ensure your app's session cookie
+How do I deploy the Super Graph service with my existing rails app? You have several options here. Esentially you need to ensure your app's session cookie will be passed to this service. 
-will be passed to this service. 
+
+#### Custom Docker Image
+
+Create a `Dockerfile` like the one below to roll your own
+custom Super Graph docker image. And to build it `docker build -t my-super-graph .`
+
+```dockerfile
+FROM dosco/super-graph:latest
+WORKDIR /app
+COPY *.yml ./
+```
 
 #### Deploy under a subdomain
 For this to work you have to ensure that the option `:domain => :all` is added to your rails app config `Application.config.session_store` this will cause your rails app to create session cookies that can be shared with sub-domains. More info here <http://excid3.com/blog/sharing-a-devise-user-session-across-subdomains-with-rails-3/>

dev.yml

@@ -50,9 +50,10 @@ auth:
 
 # auth:
 #   type: jwt
+#   provider: auth0
 #   cookie: _app_session
 #   secret: abc335bfcfdb04e50db5bb0a4d67ab9
-#   public_key_file: abc335bfcfdb04e50db5bb0a4d67ab9
+#   public_key_file: /secrets/public_key.pem
 #   public_key_type: ecdsa #rsa
 
 database:

go.mod

@@ -1,7 +1,7 @@
 module github.com/dosco/super-graph
 
 require (
-  github.com/adjust/gorails v0.0.0-20171013043634-2786ed0c03d3
+	github.com/adjust/gorails v0.0.0-20171013043634-2786ed0c03d3
 	github.com/bradfitz/gomemcache v0.0.0-20180710155616-bc664df96737
 	github.com/dgrijalva/jwt-go v3.2.0+incompatible
 	github.com/garyburd/redigo v1.6.0

prod.yml

@@ -43,9 +43,10 @@ auth:
 
 # auth:
 #   type: jwt
+#   provider: auth0
 #   cookie: _app_session
 #   secret: abc335bfcfdb04e50db5bb0a4d67ab9
-#   public_key_file: abc335bfcfdb04e50db5bb0a4d67ab9
+#   public_key_file: /secrets/public_key.pem
 #   public_key_type: ecdsa #rsa
 
 database:

serv/auth.go

@@ -15,8 +15,9 @@ const (
 )
 
 var (
-	userIDKey      = struct{}{}
+	userIDProviderKey = struct{}{}
-	errSessionData = errors.New("error decoding session data")
+	userIDKey         = struct{}{}
+	errSessionData    = errors.New("error decoding session data")
 )
 
 func headerHandler(next http.HandlerFunc) http.HandlerFunc {

serv/auth_jwt.go

@@ -4,15 +4,27 @@ import (
 	"context"
 	"io/ioutil"
 	"net/http"
+	"strings"
 
 	jwt "github.com/dgrijalva/jwt-go"
 )
 
+const (
+	jwtBase int = iota
+	jwtAuth0
+)
+
 func jwtHandler(next http.HandlerFunc) http.HandlerFunc {
 	var key interface{}
+	var jwtProvider int
 
 	cookie := conf.GetString("auth.cookie")
 
+	provider := conf.GetString("auth.provider")
+	if provider == "auth0" {
+		jwtProvider = jwtAuth0
+	}
+
 	conf.BindEnv("auth.secret", "SG_AUTH_SECRET")
 	secret := conf.GetString("auth.secret")
 
@@ -75,7 +87,17 @@ func jwtHandler(next http.HandlerFunc) http.HandlerFunc {
 		}
 
 		if claims, ok := token.Claims.(*jwt.StandardClaims); ok {
-			ctx := context.WithValue(r.Context(), userIDKey, claims.Id)
+			ctx := r.Context()
+
+			if jwtProvider == jwtAuth0 {
+				sub := strings.Split(claims.Subject, "|")
+				if len(sub) != 2 {
+					ctx = context.WithValue(ctx, userIDProviderKey, sub[0])
+					ctx = context.WithValue(ctx, userIDKey, sub[1])
+				}
+			} else {
+				ctx = context.WithValue(ctx, userIDKey, claims.Subject)
+			}
 			next.ServeHTTP(w, r.WithContext(ctx))
 		}
 

serv/http.go

@@ -153,15 +153,24 @@ func authCheck(ctx context.Context) bool {
 }
 
 func varValues(ctx context.Context) map[string]interface{} {
-	userIDFn := fasttemplate.TagFunc(func(w io.Writer, _ string) (int, error) {
+	uidFn := fasttemplate.TagFunc(func(w io.Writer, _ string) (int, error) {
 		if v := ctx.Value(userIDKey); v != nil {
 			return w.Write([]byte(v.(string)))
 		}
 		return 0, errNoUserID
 	})
 
+	uidpFn := fasttemplate.TagFunc(func(w io.Writer, _ string) (int, error) {
+		if v := ctx.Value(userIDProviderKey); v != nil {
+			return w.Write([]byte(v.(string)))
+		}
+		return 0, errNoUserID
+	})
+
 	return map[string]interface{}{
-		"USER_ID": userIDFn,
+		"USER_ID":          uidFn,
-		"user_id": userIDFn,
+		"user_id":          uidFn,
+		"USER_ID_PROVIDER": uidpFn,
+		"user_id_provider": uidpFn,
 	}
 }