push: allow registering for push notifications

Author: tulir

push.go

@@ -0,0 +1,74 @@
+// Copyright (c) 2024 Tulir Asokan
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+package whatsmeow
+
+import (
+	"context"
+	"encoding/base64"
+
+	waBinary "go.mau.fi/whatsmeow/binary"
+	"go.mau.fi/whatsmeow/types"
+)
+
+type PushConfig interface {
+	GetPushConfigAttrs() waBinary.Attrs
+}
+
+type FCMPushConfig struct {
+	Token string `json:"token"`
+}
+
+func (fpc *FCMPushConfig) GetPushConfigAttrs() waBinary.Attrs {
+	return waBinary.Attrs{
+		"id":       fpc.Token,
+		"num_acc":  1,
+		"platform": "fcm",
+	}
+}
+
+type WebPushConfig struct {
+	Endpoint string `json:"endpoint"`
+	Auth     []byte `json:"auth"`
+	P256DH   []byte `json:"p256dh"`
+}
+
+func (wpc *WebPushConfig) GetPushConfigAttrs() waBinary.Attrs {
+	return waBinary.Attrs{
+		"platform": "web",
+		"endpoint": wpc.Endpoint,
+		"auth":     base64.StdEncoding.EncodeToString(wpc.Auth),
+		"p256dh":   base64.StdEncoding.EncodeToString(wpc.P256DH),
+	}
+}
+
+func (cli *Client) GetServerPushNotificationConfig(ctx context.Context) (*waBinary.Node, error) {
+	resp, err := cli.sendIQ(infoQuery{
+		Namespace: "urn:xmpp:whatsapp:push",
+		Type:      iqGet,
+		To:        types.ServerJID,
+		Content:   []waBinary.Node{{Tag: "settings"}},
+		Context:   ctx,
+	})
+	return resp, err
+}
+
+// RegisterForPushNotifications registers a token to receive push notifications for new WhatsApp messages.
+//
+// This is generally not necessary for anything. Don't use this if you don't know what you're doing.
+func (cli *Client) RegisterForPushNotifications(ctx context.Context, pc PushConfig) error {
+	_, err := cli.sendIQ(infoQuery{
+		Namespace: "urn:xmpp:whatsapp:push",
+		Type:      iqSet,
+		To:        types.ServerJID,
+		Content: []waBinary.Node{{
+			Tag:   "config",
+			Attrs: pc.GetPushConfigAttrs(),
+		}},
+		Context: ctx,
+	})
+	return err
+}