datastax · jorgebay · Apr 28, 2020 · Apr 15, 2020 · Apr 22, 2020 · Apr 27, 2020
diff --git a/cmd/server.go b/cmd/server.go
@@ -15,12 +15,14 @@ import (
 	log2 "log"
 	"net/http"
 	"os"
+	"path"
 	"strings"
 )
 
 const defaultGraphQLPath = "/graphql"
 const defaultGraphQLSchemaPath = "/graphql-schema"
 const defaultRESTPath = "/todo"
+const defaultGraphQLPlaygroundPath = "/graphql-playground"
 
 // Environment variables prefixed with "DATA_API_" can override settings e.g. "DATA_API_HOSTS"
 const envVarPrefix = "data_api"
@@ -33,8 +35,6 @@ var serverCmd = &cobra.Command{
 	Use:   os.Args[0] + " --hosts [HOSTS] [--start-graph|--start-rest] [OPTIONS]",
 	Short: "GraphQL and REST endpoints for Apache Cassandra",
 	Args: func(cmd *cobra.Command, args []string) error {
-		// TODO: Validate GraphQL/REST paths, should they be disjointed?
-
 		hosts := viper.GetStringSlice("hosts")
 		if len(hosts) == 0 {
 			return errors.New("hosts are required")
@@ -62,6 +62,10 @@ var serverCmd = &cobra.Command{
 		startREST := viper.GetBool("start-rest")
 
 		if graphqlPort == restPort {
+			if startGraphQL && startREST && viper.GetString("graphql-path") == viper.GetString("rest-path") {
+				logger.Fatal("graphql and rest paths can not be the same when using the same port")
+			}
+
 			router := createRouter()
 			endpointNames := ""
 			if startGraphQL {
@@ -124,6 +128,8 @@ func Execute() {
 	flags.Bool("start-graphql", true, "start the GraphQL endpoint")
 	flags.String("graphql-path", defaultGraphQLPath, "GraphQL endpoint path")
 	flags.String("graphql-schema-path", defaultGraphQLSchemaPath, "GraphQL schema management path")
+	flags.Bool("graphql-playground", true, "expose a GraphQL playground route")
+	flags.String("graphql-playground-path", defaultGraphQLPlaygroundPath, "path for the GraphQL playground static file")
 	flags.Int("graphql-port", 8080, "GraphQL endpoint port")
 
 	// TODO:
@@ -208,6 +214,27 @@ func addGraphQLRoutes(router *httprouter.Router, endpoint *endpoint.DataEndpoint
 			"error", err)
 	}
 
+	if viper.GetBool("graphql-playground") {
+		playgroundPath := viper.GetString("graphql-playground-path")
+		hostAndPort := fmt.Sprintf("http://localhost:%d", viper.GetInt("graphql-port"))
+		defaultPath := rootPath
+		if singleKeyspace == "" {
+			// For multi-keyspace mode, use /graphql/<any_keyspace> as default playground endpoint url
+			keyspaces, err := endpoint.Keyspaces()
+			if err != nil {
+				logger.Fatal("could not retrieve keyspaces", "error", err)
+			}
+
+			if len(keyspaces) > 0 {
+				defaultPath = path.Join(rootPath, keyspaces[0])
+			}
+		}
+		defaultEndpointUrl := fmt.Sprintf("%s%s", hostAndPort, defaultPath)
+		logger.Info("get started by visiting the GraphQL playground",
+			"url", fmt.Sprintf("%s%s", hostAndPort, playgroundPath))
+		router.GET(playgroundPath, graphql.GetPlaygroundHandle(defaultEndpointUrl))
+	}
+
 	for _, route := range routes {
 		router.Handler(route.Method, route.Pattern, route.Handler)
 	}

diff --git a/endpoint/endpoint.go b/endpoint/endpoint.go
@@ -131,3 +131,8 @@ func (e *DataEndpoint) RoutesKeyspaceGraphQL(pattern string, ksName string) ([]g
 func (e *DataEndpoint) RoutesSchemaManagementGraphQL(pattern string, ops config.SchemaOperations) ([]graphql.Route, error) {
 	return e.graphQLRouteGen.RoutesSchemaManagement(pattern, ops)
 }
+
+// Keyspaces gets a slice of keyspace names that are considered by the endpoint when used in multi-keyspace mode.
+func (e *DataEndpoint) Keyspaces() ([]string, error) {
+	return e.graphQLRouteGen.Keyspaces()
+}
diff --git a/graphql/playground.go b/graphql/playground.go
@@ -0,0 +1,74 @@
+package graphql
+
+import (
+	"fmt"
+	"github.com/julienschmidt/httprouter"
+	"net/http"
+)
+
+func GetPlaygroundHandle(defaultEndpointUrl string) httprouter.Handle {
+	return func(w http.ResponseWriter, r *http.Request, _ httprouter.Params) {
+		html := `
+<!DOCTYPE html>
+<html>
+
+<head>
+  <meta charset=utf-8/>
+  <meta name="viewport" content="user-scalable=no, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0, minimal-ui">
+  <title>GraphQL Playground</title>
+  <link rel="stylesheet" href="//cdn.jsdelivr.net/npm/[email protected]/build/static/css/index.css" />
+  <link rel="shortcut icon" href="//cdn.jsdelivr.net/npm/[email protected]/build/favicon.png" />
+  <script src="//cdn.jsdelivr.net/npm/[email protected]/build/static/js/middleware.js"></script>
+</head>
+
+<body>
+  <div id="root">
+    <style>
+      body {
+        background-color: rgb(23, 42, 58);
+        font-family: Open Sans, sans-serif;
+        height: 90vh;
+      }
+
+      #root {
+        height: 100%%;
+        width: 100%%;
+        display: flex;
+        align-items: center;
+        justify-content: center;
+      }
+
+      .loading {
+        font-size: 32px;
+        font-weight: 200;
+        color: rgba(255, 255, 255, .6);
+        margin-left: 20px;
+      }
+
+      img {
+        width: 78px;
+        height: 78px;
+      }
+
+      .title {
+        font-weight: 400;
+      }
+    </style>
+    <img src='//cdn.jsdelivr.net/npm/[email protected]/build/logo.png' alt=''>
+    <div class="loading"> Loading
+      <span class="title">GraphQL Playground</span>
+    </div>
+  </div>
+  <script>window.addEventListener('load', function (event) {
+      GraphQLPlayground.init(document.getElementById('root'), {
+        endpoint: '%s'
+      })
+    })</script>
+</body>
+
+</html>
+`
+		html = fmt.Sprintf(html, defaultEndpointUrl)
+		fmt.Fprint(w, html)
+	}
+}
diff --git a/graphql/routes.go b/graphql/routes.go
@@ -103,6 +103,24 @@ func (rg *RouteGenerator) Routes(pattern string, singleKeyspace string) ([]Route
 	}), nil
 }
 
+// Keyspaces gets a slice of keyspace names that are considered by the route generator.
+func (rg *RouteGenerator) Keyspaces() ([]string, error) {
+	keyspaces, err := rg.dbClient.Keyspaces()
+
+	if err != nil {
+		return nil, err
+	}
+
+	result := make([]string, 0, len(keyspaces))
+	for _, ksName := range keyspaces {
+		if !rg.schemaGen.isKeyspaceExcluded(ksName) {
+			result = append(result, ksName)
+		}
+	}
+
+	return result, nil
+}
+
 func getPathParser(root string) func(string) string {
 	if !strings.HasSuffix(root, "/") {
 		root += "/"