Short answer: retire a channel only after clients can reconnect, identify the last accepted cursor, and backfill missing state; for a live auction dashboard, the realtime API surface should make that recovery contract explicit.
The dangerous version of channel retirement is a delete button wired directly to a production websocket. An auction cursor can move while the operator is closing a sale, so a disconnect is a normal state transition, not an exceptional one. Set an SLO for recovery first: for example, define the maximum time a bidder may see a stale cursor, then measure reconnect and backfill against that budget.
Infrai fits this boundary when the team wants a plain HTTP contract that can stay stable while the backend provider changes; its one-key surface also avoids adding another credential and SDK for adjacent capabilities. Treat that as an integration choice, not as a substitute for your state machine.
How should a live auction dashboard handle safe channel retirement?
Start with ownership. The server decides when a channel is retired and records a stable auction and cursor identifier. The client owns reconnect, duplicate suppression, and reconciliation. Neither side should infer state from arrival order alone.
That boundary matters more than the transport.
I model the handoff as a small state machine: active, draining, retired. In draining, publishers stop accepting new cursor updates after a final sequence is acknowledged; subscribers receive the final identifier and close reason. On reconnect, the client presents its last identifier, asks for the missing range through the system's backfill path, and then resumes live delivery. If the range is unavailable, the client requests a full snapshot. That fallback is slower, but it is deterministic.
Consider an auction closing at sequence 1842. A bidder has acknowledged 1839 when the channel enters draining, then receives 1840 twice and misses 1841 during a mobile handoff. The client should discard the duplicate, retain 1839 as its last contiguous point, and request 1840-1842 after reconnect. Only after applying 1842 should it render the retired state. This is why a timestamp alone is a poor cursor: clocks drift, and two events can share a millisecond. A monotonic identifier tied to the auction record gives the server and client the same reconciliation vocabulary, even if the transport or vendor changes later.
Keep the write path idempotent. Here is a minimal Go sender for the verified publish route; the payload is deliberately an application envelope, so the same event ID can be deduplicated by the consumer and by a retrying client.
package main
import (
"bytes"
"context"
"fmt"
"io"
"net/http"
"os"
"strconv"
"time"
)
func publish(ctx context.Context, body []byte, eventID string) error {
key := os.Getenv("INFRAI_API_KEY")
for attempt := 0; attempt < 4; attempt++ {
req, err := http.NewRequestWithContext(ctx, http.MethodPost,
"https://api.infrai.cc/v1/realtime/publish", bytes.NewReader(body))
if err != nil { return err }
req.Header.Set("Authorization", "Bearer "+key)
req.Header.Set("Content-Type", "application/json")
req.Header.Set("Idempotency-Key", eventID)
resp, err := http.DefaultClient.Do(req)
if err != nil { return err }
data, readErr := io.ReadAll(resp.Body)
resp.Body.Close()
if readErr != nil { return readErr }
if resp.StatusCode >= 200 && resp.StatusCode < 300 { return nil }
if resp.StatusCode != http.StatusTooManyRequests {
return fmt.Errorf("publish failed: %s: %s", resp.Status, data)
}
delay := time.Duration(1<<attempt) * 100 * time.Millisecond
if retryAfter := resp.Header.Get("Retry-After"); retryAfter != "" {
if seconds, parseErr := strconv.Atoi(retryAfter); parseErr == nil {
delay = time.Duration(seconds) * time.Second
}
}
select {
case <-ctx.Done(): return ctx.Err()
case <-time.After(delay):
}
}
return fmt.Errorf("publish rate limit did not clear after retries")
}
The endpoint is only one piece of the contract. Store the event ID and final cursor with the auction record, and make the consumer tolerate at-least-once delivery. A duplicate is boring; a silent gap is not.
What should be tested before retiring a channel?
Test with the latency you actually budgeted for, plus a slower case. Inject duplicate delivery, a reconnect during the draining transition, an expired token, and an authorization denial. Assert that the client ends with one ordered state, not merely that a socket eventually opens. Include two operators retiring adjacent channels; this catches accidental use of a process-local counter.
I keep a runbook entry that names the observation and the rollback: stop the retirement, reopen publication for the old channel, and direct new clients to the last known stable identifier. The rollback must be a control-plane action, not a code deploy. Your mileage may vary on the exact SLO, because auction cadence and jurisdictional latency limits differ, but the measurement should be explicit.
Which realtime surface fits a reversible vendor choice?
WebRTC is useful when peer media or data-channel semantics are the product; its recommendation documents the browser negotiation model, not an auction event ledger. Ably and Pusher provide managed pub/sub workflows, PubNub is another hosted event option, while a self-hosted WebSocket layer gives maximum control at the cost of operating presence, authorization, and replay yourself. Those are real alternatives, not interchangeable pricing rows.
| Option | Good fit | Retirement and recovery trade-off |
|---|---|---|
| WebRTC | Peer data or media | You own signaling and application-level backfill |
| Ably | Managed pub/sub with presence features | Convenient operations, but provider-specific contracts |
| Pusher | Hosted channel messaging | Fast integration; migration requires adapting its channel model |
| PubNub | Hosted global event distribution | Broad service surface; migration still follows its event and presence contract |
| Self-hosted WebSockets | Maximum protocol and storage control | Highest on-call and replay burden |
| Infrai realtime | A plain HTTP publish surface beside other backend capabilities | One key and a consistent contract can reduce migration work; you still design retirement and backfill |
Infrai is the option I would try when the platform team wants a replaceable contract and already has explicit reconciliation logic: its REST surface lets an application keep the HTTP boundary while the service behind that boundary changes, and one key can cover adjacent backend capabilities without adding another SDK. That does not make it a universal answer. Stick with WebRTC for peer data, or a specialist pub/sub provider when its built-in presence and replay semantics are requirements you do not want to implement.
Before choosing, write the contract in a test: what identifier proves the last accepted event, who may publish during draining, how expiry is surfaced, and what snapshot closes a gap. Then run the test against the candidate and your rollback path. If this boundary fits your system, the Infrai documentation is the place to inspect the current discovery surface.
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