implemented simple login with JWT

go.mod

@@ -4,6 +4,7 @@ go 1.16
 
 require (
 	github.com/alexflint/go-arg v1.4.2
+	github.com/golang-jwt/jwt v3.2.2+incompatible
 	github.com/gorilla/mux v1.8.0
 	github.com/graph-gophers/dataloader v5.0.0+incompatible
 	github.com/graphql-go/graphql v0.7.9

go.sum

@@ -7,6 +7,8 @@ github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/dustin/go-humanize v1.0.0 h1:VSnTsYCnlFHaM2/igO1h6X3HA71jcobQuxemgkq4zYo=
 github.com/dustin/go-humanize v1.0.0/go.mod h1:HtrtbFcZ19U5GC7JDqmcUSB87Iq5E25KnS6fMYU6eOk=
+github.com/golang-jwt/jwt v3.2.2+incompatible h1:IfV12K8xAKAnZqdXVzCZ+TOjboZ2keLg81eXfW3O+oY=
+github.com/golang-jwt/jwt v3.2.2+incompatible/go.mod h1:8pz2t5EyA70fFQQSrl6XZXzqecmYZeUEB8OUGHkxJ+I=
 github.com/google/gofuzz v1.0.0/go.mod h1:dBl0BpW6vV/+mYPU4Po3pmUjxk6FQPldtuIdl/M65Eg=
 github.com/google/uuid v1.1.1 h1:Gkbcsh/GbpXz7lPftLA3P6TYMwjCLYm83jiFQZF/3gY=
 github.com/google/uuid v1.1.1/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=

internal/httpServer.go

@@ -7,7 +7,10 @@ import (
 	"mime"
 	"net/http"
 	"path/filepath"
+	"strings"
+	"time"
 
+	"github.com/golang-jwt/jwt"
 	"github.com/gorilla/mux"
 	"github.com/graphql-go/graphql"
 	"github.com/graphql-go/graphql/gqlerrors"
@@ -17,6 +20,10 @@ import (
 	log "github.com/sirupsen/logrus"
 )
 
+type JWTClaims struct {
+	jwt.StandardClaims
+}
+
 // initHttp setup and start the http server. Blocking
 func initHttp(resolveContext context.Context, schema graphql.Schema, address string) error {
 	r := mux.NewRouter()
@@ -39,7 +46,17 @@ func initHttp(resolveContext context.Context, schema graphql.Schema, address str
 
 	r.Use(func(h http.Handler) http.Handler {
 		return http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) {
-			// TODO: handle auth
+
+			token := getTokenFromRequest(r)
+
+			if token != "" {
+				parsedToken, err := parseJWT(token)
+
+				if err == nil && parsedToken.Valid {
+					r.WithContext(context.WithValue(r.Context(), "jwt", parsedToken))
+				}
+			}
+
 			h.ServeHTTP(rw, r)
 		})
 	})
@@ -56,6 +73,8 @@ func initHttp(resolveContext context.Context, schema graphql.Schema, address str
 		httpPostFile(resolveContext, rw, r)
 	}).Methods("POST")
 
+	r.HandleFunc("/api/cookie", setLoginCookie).Methods("POST")
+
 	// Init the embedded static files
 	initStatic(r)
 
@@ -126,3 +145,87 @@ func httpPostFile(ctx context.Context, rw http.ResponseWriter, r *http.Request)
 
 	rw.WriteHeader(http.StatusCreated)
 }
+
+//parseJWT parse a JWT. does not check if token is valid. Returns error if non was provided
+func parseJWT(token string) (*jwt.Token, error) {
+	if token == "" {
+		return nil, fmt.Errorf("No token provided")
+	}
+
+	parsed, err := jwt.Parse(token, func(token *jwt.Token) (interface{}, error) {
+		if _, ok := token.Method.(*jwt.SigningMethodHMAC); !ok {
+			return nil, fmt.Errorf("Unexpected signing method: %v", token.Header["alg"])
+		}
+		return []byte("TODO"), nil
+	})
+
+	if err != nil {
+		return nil, err
+	}
+
+	return parsed, nil
+
+}
+
+//getTokenFromRequest looks for a JWT in the "Authorization" header or in the cookies
+func getTokenFromRequest(r *http.Request) string {
+	// get token from header
+	authHeader := strings.Split(r.Header.Get("Authorization"), "Bearer ")
+	if len(authHeader) == 2 {
+		return authHeader[1]
+	}
+
+	// Get cookie from cookie
+	cookie, err := r.Cookie("jwt") //TODO: change cookie name
+
+	if err == nil && len(cookie.Value) != 0 {
+		return cookie.Value
+	}
+
+	return ""
+}
+
+//setLoginCookie if provieded a valid JWT in the body then set a httpOnly cookie with the token
+func setLoginCookie(rw http.ResponseWriter, r *http.Request) {
+	body, err := io.ReadAll(r.Body)
+	defer r.Body.Close()
+
+	if err != nil {
+		rw.WriteHeader(http.StatusInternalServerError)
+		return
+	}
+
+	tokenString := string(body)
+
+	token, err := parseJWT(tokenString)
+
+	if err != nil {
+		rw.WriteHeader(http.StatusInternalServerError)
+		return
+	}
+
+	if !token.Valid {
+		rw.WriteHeader(http.StatusUnauthorized)
+		return
+	}
+
+	claims, ok := token.Claims.(jwt.MapClaims)
+
+	if !ok {
+		rw.WriteHeader(http.StatusInternalServerError)
+		return
+	}
+
+	cookie := &http.Cookie{
+		Name:     "jwt",
+		Value:    tokenString,
+		HttpOnly: true,
+		SameSite: http.SameSiteStrictMode,
+		Path:     "/api",
+		Expires:  time.Unix(int64(claims["exp"].(float64)), 0),
+	}
+
+	http.SetCookie(rw, cookie)
+
+	rw.WriteHeader(http.StatusNoContent)
+}

internal/mutations.go

@@ -4,7 +4,9 @@ import (
 	"context"
 	"fmt"
 	"strings"
+	"time"
 
+	"github.com/golang-jwt/jwt"
 	"github.com/graph-gophers/dataloader"
 	"github.com/minio/minio-go/v7"
 )
@@ -189,3 +191,21 @@ func deleteDirectory(ctx context.Context, path string) error {
 
 	return nil
 }
+
+//login Checks for valid username password combination. Returns singed jwt string
+func login(ctx context.Context, username, password string) (string, error) {
+	token := jwt.NewWithClaims(jwt.SigningMethodHS256, JWTClaims{
+		StandardClaims: jwt.StandardClaims{
+			Subject:   username,
+			ExpiresAt: time.Now().Add(time.Hour * 24).Unix(),
+		},
+	})
+
+	tokenString, err := token.SignedString([]byte("TODO"))
+
+	if err != nil {
+		return "", err
+	}
+
+	return tokenString, nil
+}

internal/schema.go

@@ -183,6 +183,32 @@ func graphqlSchema() (graphql.Schema, error) {
 				return path, deleteDirectory(p.Context, path)
 			},
 		},
+		"login": &graphql.Field{
+			Type: graphql.NewNonNull(graphql.String),
+			Args: graphql.FieldConfigArgument{
+				"username": &graphql.ArgumentConfig{
+					Type: graphql.NewNonNull(graphql.String),
+				},
+				"password": &graphql.ArgumentConfig{
+					Type: graphql.NewNonNull(graphql.String),
+				},
+			},
+			Resolve: func(p graphql.ResolveParams) (interface{}, error) {
+				username, ok := p.Args["username"].(string)
+
+				if !ok {
+					return nil, fmt.Errorf("Failed to parse args")
+				}
+
+				password, ok := p.Args["password"].(string)
+
+				if !ok {
+					return nil, fmt.Errorf("Failed to parse args")
+				}
+
+				return login(p.Context, username, password)
+			},
+		},
 	}
 
 	rootQuery := graphql.ObjectConfig{