WebPush

// includes: sgcHTML_WebPush.hpp, sgcHTMX_Engine_Server.hpp
// Enterprise and All-Access only: compiled when SGC_WEBPUSH is defined

String vPublic, vPrivate;
// once, then keep both values in your own settings
TsgcHTMLWebPush::GenerateVAPIDKeys(vPublic, vPrivate);

FPush = new TsgcHTMLWebPush(this);
FPush->VAPIDPublicKey = vPublic;
FPush->VAPIDPrivateKey = vPrivate;
FPush->Subject = "mailto:support@example.com";
FPush->OnSaveSubscription = PushSave;
FPush->OnLoadSubscriptions = PushLoad;
FPush->OnDeleteSubscription = PushDelete;
FPush->OnSubscriptionExpired = PushExpired;
FPush->Enabled = true;

// oHTMX is a TsgcHTMX_Engine_Server
oHTMX->WebPush = FPush;
oHTMX->Template->WebPushEnabled = true;

// later, from anywhere in the application
FPush->Send("u1", "Order shipped",
  "Order 1042 left the warehouse", "/orders/1042");

// the application owns the storage
void __fastcall TForm1::PushSave(TObject *Sender,
  const UnicodeString aUserID, const UnicodeString aEndpoint,
  const UnicodeString aP256dh, const UnicodeString aAuth)
{
  SaveSubscription(aUserID, aEndpoint, aP256dh, aAuth);
}

void __fastcall TForm1::PushLoad(TObject *Sender, const UnicodeString aUserID,
  TsgcHTMLWebPushSubscriptions *const aList)
{
  // one Add per stored subscription of this user
  for (const TStoredSubscription &row : LoadSubscriptions(aUserID))
    aList->Add(row.Endpoint, row.P256dh, row.Auth);
}

// in the page, a click starts the permission prompt:
// <button data-sgc-webpush>Enable notifications</button>

using esegece.sgcWebSockets;

// once, then keep both values in your own settings
TsgcHTMLWebPush.GenerateVAPIDKeys(out var pub, out var priv);

var push = new TsgcHTMLWebPush();
push.VAPIDPublicKey = pub;
push.VAPIDPrivateKey = priv;
push.Subject = "mailto:support@example.com";

// the application owns the storage
push.OnSaveSubscription += (sender, aUserID, aEndpoint, aP256dh, aAuth) =>
    SaveSubscription(aUserID, aEndpoint, aP256dh, aAuth);
push.OnLoadSubscriptions += (sender, aUserID, aList) =>
{
    // one Add per stored subscription of this user
    foreach (var row in LoadSubscriptions(aUserID))
        aList.Add(row.Endpoint, row.P256dh, row.Auth);
};
push.OnDeleteSubscription += (sender, aUserID, aEndpoint) =>
    DeleteSubscription(aUserID, aEndpoint);
push.OnSubscriptionExpired += (sender, aUserID, aEndpoint, aStatusCode) =>
    DeleteSubscription(aUserID, aEndpoint);   // 404 or 410: gone for good
push.Enabled = true;

// htmx is a TsgcHTMX_Engine_Server
htmx.WebPush = push;
htmx.Template.WebPushEnabled = true;

// later, from anywhere in the application
int delivered = push.Send("u1", "Order shipped",
    "Order 1042 left the warehouse", "/orders/1042");

// in the page, a click starts the permission prompt:
// <button data-sgc-webpush>Enable notifications</button>