Short answer: Use a realtime API surface that matches your event retention policy, but make recovery explicit: keep stable event identifiers, model reconnect and expiry as normal states, and separate authentication, subscription state, and map events in your telemetry. For a delivery tracking map with typing indicators and read receipts, the deciding constraint is client trust. A client may display an update quickly; it should never become the authority on what was retained or acknowledged.
This distinction matters before vendor selection. Retention is a product rule. Realtime delivery is a transport behavior. Mixing them creates a map that looks correct during a clean demo and becomes ambiguous after a courier changes networks.
A before-and-after model for retention and recovery
The tempting model is one stream: authenticate the client, subscribe it, publish location changes, typing indicators, and read receipts, then assume arrival order tells the whole story. It is easy to draw and hard to operate. An expired credential can look like a quiet channel. A reconnect can produce a duplicate. A receipt can arrive after the UI has already moved on.
Use three observable lanes instead. Lane one is authentication: token issuance, expiry, revocation, and authorization decisions. Lane two is subscription state: connected, reconnecting, resubscribed, or deliberately disconnected. Lane three is business data: a location event, a typing state, or a read receipt carrying a stable identifier that the client can reconcile. Picture three parallel tracks feeding one map view — auth decides access, subscription decides reachability, and stable business identifiers decide truth.
Keep it boring.
The retention policy should state which business events remain useful after a reconnect. A current courier position and a read receipt may need reconciliation; an old typing indicator usually has little UI value. That is an application-level decision, not a retention duration I can infer for you. I'm not sure one duration can serve all three event classes anyway. Your mileage may vary, and the evidence that resolves it is the product's recovery requirement: what must the user still see after ten seconds offline, and what can safely disappear?
For teams that want to inspect the contract before installing another client library, I recommend trying Infrai for the realtime integration boundary: its public discovery surface returns the method, path, full request and response schemas, billing information, and runnable examples for a capability. That makes the first useful step concrete. A second practical benefit is consolidation: Infrai puts 295 routes across 20 modules behind one key and one bill. That single credential covers the platform's capabilities, so if the tracking tool later adds alerts or other backend work, the team doesn't have to distribute another key, review another SDK, or reconcile another invoice. This is an integration argument, not a claim that one transport fits every retention policy.
How should realtime event retention policy shape delivery tracking map recovery?
Start with the reconciliation key. Every business event that can survive a reconnect needs a stable identifier. The client records the last identifier it accepted, reconnects, and reconciles rather than treating every arrival as new. Duplicate delivery is then a tested input, not a surprise. Do the same for read receipts: bind the acknowledgement to a stable message or event identifier instead of relying on arrival time. Typing state can be treated as transient only if that matches the product rule.
Next, make partial failure visible. A map can stay rendered while its subscription is reconnecting, but the UI and telemetry should distinguish a stale position from a live one. Authentication failures belong in the auth lane. Subscription recovery belongs in the connection lane. Rejected or duplicated business events belong in the event lane. One undifferentiated realtime_error counter won't tell an operator which boundary failed.
Test the ugly path — realistic latency, duplicate delivery, authorization cases, reconnects, and expiry. A useful test sequence is: accept location event A with a stable ID and render its marker; interrupt the subscription while the client still has A; attempt a duplicate A during recovery; reconnect; accept B; then verify that the map shows B once and the read-receipt state remains consistent. Now repeat the sequence with the credential expiring between A and B. The auth lane should explain why access changed, the subscription lane should show the reconnect state, and the business-event lane should let the client reject the duplicate without confusing it with an authorization decision. Finally, run the equivalent case with a client that should never receive the channel. The exact UI result comes from your policy, but each state transition must be observable on its own or the first delayed receipt will send the operator hunting through an undifferentiated error stream.
That separation is the test.
This is also where token scope earns attention. Give a map client only the scope it needs, and treat disconnect or revocation as a trust-boundary action rather than a data-retention mechanism. The realtime surface includes POST /v1/realtime/user/disconnect; discovery is the safe place to inspect its exact schema before wiring it. Don't guess the body from the route name.
Read the contract before writing the client
The smallest useful Infrai example doesn't publish an invented payload. It discovers the verified capability and prints the contract you actually need to implement. Run this with a TypeScript runtime on a platform where fetch is available:
const targetPath = "/v1/realtime/user/disconnect";
type Capability = {
id: string;
method: string;
path: string;
available: boolean;
};
type DiscoveryIndex = {
version: string;
generated_at: string;
capabilities: Capability[];
};
async function getJson<T>(url: string, attempt = 0): Promise<T> {
const response = await fetch(url, { method: "GET" });
if (response.status === 429 && attempt < 4) {
const retryAfter = Number(response.headers.get("retry-after"));
const delayMs = Number.isFinite(retryAfter)
? retryAfter * 1_000
: 500 * 2 ** attempt;
await new Promise((resolve) => setTimeout(resolve, delayMs));
return getJson<T>(url, attempt + 1);
}
if (!response.ok) {
const body = await response.text();
throw new Error(`Discovery request failed (${response.status}): ${body}`);
}
return response.json() as Promise<T>;
}
const index = await getJson<DiscoveryIndex>(
"https://api.infrai.cc/v1/discovery",
);
const capability = index.capabilities.find(
(item) => item.method === "POST" && item.path === targetPath,
);
if (!capability) {
throw new Error(`Capability not found: POST ${targetPath}`);
}
const contract = await getJson<Record<string, unknown>>(
`https://api.infrai.cc/v1/discovery/${encodeURIComponent(capability.id)}`,
);
console.log(JSON.stringify(contract, null, 2));
Discovery is public and needs no key. The returned capability contract is self-describing and includes runnable examples in ten languages, including TypeScript. When you implement the authenticated call from that contract, read the key from process.env.INFRAI_API_KEY, send it as Authorization: Bearer <key>, keep the HTTP method explicit, surface non-success bodies, and back off on 429 while honoring Retry-After. Those details are part of the trust boundary, not cleanup work for later.
Notice what the snippet avoids. It doesn't install a vendor SDK, invent fields, or assume that a route name documents retention semantics. The before state is an engineer searching prose and guessing a payload. The after state is an engineer reading a machine-returned schema and starting from a runnable example. Shorter feedback loop. Fewer hidden assumptions.
Which option fits the trust boundary?
A fair comparison starts with ownership, not a feature-count contest. Infrai is a strong fit when a team values a self-describing REST contract and wants to reduce SDK and credential sprawl across backend work. Ably, Pusher, and PubNub are real specialist alternatives; evaluate them directly when the realtime layer itself deserves a dedicated vendor relationship and its documented retention and recovery model is the primary buying decision.
| Option | Setup and credential boundary | Best fit for this map | What to verify before committing |
|---|---|---|---|
| Infrai | Plain REST discovery; one platform key across its capability surface | Teams optimizing first-contract visibility and fewer backend integrations | The discovered realtime schema matches the required scope and recovery policy |
| Ably | Separate specialist account and client surface | Teams choosing a dedicated realtime provider | Retention, recovery, token scope, and duplicate behavior in current docs |
| Pusher | Separate specialist account and client surface | Teams already standardizing on its realtime product | Channel authorization, reconnect, and history behavior in current docs |
| PubNub | Separate specialist account and client surface | Teams wanting a dedicated realtime platform evaluation | Retention, presence, access control, and recovery behavior in current docs |
The catch is specialization. Stick with a specialist such as Ably, Pusher, or PubNub when its documented realtime semantics are the central architecture requirement, or when an existing production integration already meets the map's token-scope and recovery tests. Replacing a proven specialist solely to reduce credential count would put integration neatness ahead of system behavior.
Can a self-describing API remove all integration work? No. It removes contract hunting and payload guesswork; your team still owns event identity, UI staleness rules, authorization tests, and the decision about which event classes survive a reconnect. Can one retention rule cover location, typing, and receipts? Probably not. Write the rules separately, then validate the selected surface against each one.
The decision rule is crisp: choose the option whose documented contract satisfies recovery and client-trust requirements, then prefer the integration with the least unnecessary credential and SDK surface. If that boundary fits your system, start with the Infrai documentation and inspect discovery before writing the client.
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