feat: add initial support for fleet provisioning

fixes seqsense#171

examples/fleetprovisioning/.gitignore

@@ -0,0 +1,6 @@
+fleetprovisioning
+root-CA.crt
+certificate.pem.crt
+certificate-run.pem.crt
+private.pem.key
+private-run.pem.key

examples/fleetprovisioning/main.go

@@ -0,0 +1,163 @@
+// Copyright 2020 SEQSENSE, Inc.
+//
+// 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 (
+	"context"
+	"fmt"
+	"os"
+	"time"
+
+	"github.com/at-wat/mqtt-go"
+	"github.com/seqsense/aws-iot-device-sdk-go/v6"
+	"github.com/seqsense/aws-iot-device-sdk-go/v6/fleetprovisioning"
+)
+
+func main() {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	if len(os.Args) != 4 {
+		println("usage: fleetprovisioning AWS_IOT_ENDPOINT CLIENT_ID TEMPLATE_NAME")
+		println("")
+		println("This example registers a new thing in AWS IoT.")
+		println("TEMPLATE_NAME must be created to your account of AWS IoT beforehand.")
+		println("")
+		println("Following files must be placed under the current working directory:")
+		println("         root-CA.crt: root CA certificate")
+		println(" certificate.pem.crt: client certificate with assigned policy to provision devices")
+		println("  - see https://docs.aws.amazon.com/iot/latest/developerguide/provision-wo-cert.html")
+		println("     private.pem.key: private key associated to above certificate")
+		os.Exit(1)
+	}
+	host := os.Args[1]
+	thingName := os.Args[2]
+	templateName := os.Args[3]
+
+	for _, file := range []string{
+		"root-CA.crt",
+		"certificate.pem.crt",
+		"private.pem.key",
+	} {
+		_, err := os.Stat(file)
+		if os.IsNotExist(err) {
+			println(file, "not found")
+			os.Exit(1)
+		}
+		if err != nil {
+			println(file, err)
+		}
+	}
+
+	cli, err := awsiotdev.New(
+		thingName,
+		&mqtt.URLDialer{
+			URL: fmt.Sprintf("mqtts://%s:8883", host),
+			Options: []mqtt.DialOption{
+				mqtt.WithTLSCertFiles(
+					host,
+					"root-CA.crt",
+					"certificate.pem.crt",
+					"private.pem.key",
+				),
+				mqtt.WithConnStateHandler(func(s mqtt.ConnState, err error) {
+					fmt.Printf("%s: %v\n", s, err)
+				}),
+			},
+		},
+		mqtt.WithReconnectWait(500*time.Millisecond, 2*time.Second),
+	)
+	if err != nil {
+		panic(err)
+	}
+
+	// Multiplex message handler to route messages to multiple features.
+	var mux mqtt.ServeMux
+	cli.Handle(&mux)
+
+	f, err := fleetprovisioning.New(ctx, cli, templateName)
+	if err != nil {
+		panic(err)
+	}
+	f.OnError(func(err error) {
+		fmt.Printf("async error: %v\n", err)
+	})
+	mux.Handle("#", f) // Handle messages.
+
+	if _, err := cli.Connect(ctx,
+		thingName,
+		mqtt.WithKeepAlive(30),
+	); err != nil {
+		panic(err)
+	}
+	println("Connected to", host)
+
+	_, _, _, certToken, err := f.CreateKeysAndCertificate(ctx)
+	if err != nil {
+		panic(err)
+	}
+	println("Created keys and certificate")
+
+	cert, err := os.OpenFile("certificate-run.pem.crt", os.O_CREATE|os.O_WRONLY, 0644)
+	if err != nil {
+		panic(err)
+	}
+	key, err := os.OpenFile("private-run.pem.key", os.O_CREATE|os.O_WRONLY, 0644)
+	if err != nil {
+		panic(err)
+	}
+	f.WriteCertificate(cert)
+	f.WritePrivateKey(key)
+	cert.Close()
+	key.Close()
+	thingName, _, err = f.RegisterThing(ctx, certToken, map[string]string{"SerialNumber": "124"})
+	if err != nil {
+		panic(err)
+	}
+	println("Registered thing:", thingName)
+
+	cli.Disconnect(ctx)
+
+	cli, err = awsiotdev.New(
+		thingName,
+		&mqtt.URLDialer{
+			URL: fmt.Sprintf("mqtts://%s:8883", host),
+			Options: []mqtt.DialOption{
+				mqtt.WithTLSCertFiles(
+					host,
+					"root-CA.crt",
+					"certificate-run.pem.crt",
+					"private-run.pem.key",
+				),
+				mqtt.WithConnStateHandler(func(s mqtt.ConnState, err error) {
+					fmt.Printf("%s: %v\n", s, err)
+				}),
+			},
+		},
+		mqtt.WithReconnectWait(500*time.Millisecond, 2*time.Second),
+	)
+
+	cli.Handle(&mux)
+
+	if _, err := cli.Connect(ctx,
+		thingName,
+		mqtt.WithKeepAlive(30),
+	); err != nil {
+		panic(err)
+	}
+	println("Connected to", host)
+
+	select {}
+}