Multi-personality polylith binary (#1552)

* Initial work oon multipersonality binary

* Remove old binaries

* Monolith and polylith binaries

* Better logging

* dendrite-poly-multi

* Fix path

* Copyright notices etc

* Tweaks

* Update Docker, INSTALL.md

* Take first argument if flags package doesn't find any args

* Postgres 9.6 or later, fix some more Docker stuff

* Don't create unnecessary e2ekey DB

* Run go mod tidy

cmd/dendrite-polylith-multi/main.go

@@ -0,0 +1,78 @@
+// 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 main
+
+import (
+	"flag"
+	"os"
+	"strings"
+
+	"github.com/matrix-org/dendrite/cmd/dendrite-polylith-multi/personalities"
+	"github.com/matrix-org/dendrite/internal/config"
+	"github.com/matrix-org/dendrite/internal/setup"
+	"github.com/sirupsen/logrus"
+)
+
+type entrypoint func(base *setup.BaseDendrite, cfg *config.Dendrite)
+
+func main() {
+	cfg := setup.ParseFlags(true)
+
+	component := ""
+	if flag.NFlag() > 0 {
+		component = flag.Arg(0) // ./dendrite-polylith-multi --config=... clientapi
+	} else if len(os.Args) > 1 {
+		component = os.Args[1] // ./dendrite-polylith-multi clientapi
+	}
+
+	components := map[string]entrypoint{
+		"appservice":       personalities.Appservice,
+		"clientapi":        personalities.ClientAPI,
+		"eduserver":        personalities.EDUServer,
+		"federationapi":    personalities.FederationAPI,
+		"federationsender": personalities.FederationSender,
+		"keyserver":        personalities.KeyServer,
+		"mediaapi":         personalities.MediaAPI,
+		"roomserver":       personalities.RoomServer,
+		"signingkeyserver": personalities.SigningKeyServer,
+		"syncapi":          personalities.SyncAPI,
+		"userapi":          personalities.UserAPI,
+	}
+
+	start, ok := components[component]
+	if !ok {
+		if component == "" {
+			logrus.Errorf("No component specified")
+			logrus.Info("The first argument on the command line must be the name of the component to run")
+		} else {
+			logrus.Errorf("Unknown component %q specified", component)
+		}
+
+		var list []string
+		for c := range components {
+			list = append(list, c)
+		}
+		logrus.Infof("Valid components: %s", strings.Join(list, ", "))
+
+		os.Exit(1)
+	}
+
+	logrus.Infof("Starting %q component", component)
+
+	base := setup.NewBaseDendrite(cfg, component, false) // TODO
+	defer base.Close()                                   // nolint: errcheck
+
+	start(base, cfg)
+}