Top-level setup package (#1605)

* Move config, setup, mscs into "setup" top-level folder

* oops, forgot the EDU server

* Add setup

* goimports

setup/flags.go

@@ -0,0 +1,52 @@
+// Copyright 2020 The Matrix.org Foundation C.I.C.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package setup
+
+import (
+	"flag"
+	"fmt"
+	"os"
+
+	"github.com/matrix-org/dendrite/internal"
+	"github.com/matrix-org/dendrite/setup/config"
+	"github.com/sirupsen/logrus"
+)
+
+var (
+	configPath = flag.String("config", "dendrite.yaml", "The path to the config file. For more information, see the config file in this repository.")
+	version    = flag.Bool("version", false, "Shows the current version and exits immediately.")
+)
+
+// ParseFlags parses the commandline flags and uses them to create a config.
+func ParseFlags(monolith bool) *config.Dendrite {
+	flag.Parse()
+
+	if *version {
+		fmt.Println(internal.VersionString())
+		os.Exit(0)
+	}
+
+	if *configPath == "" {
+		logrus.Fatal("--config must be supplied")
+	}
+
+	cfg, err := config.Load(*configPath, monolith)
+
+	if err != nil {
+		logrus.Fatalf("Invalid config file: %s", err)
+	}
+
+	return cfg
+}