Sessions & security
Which key goes where, how a session token is made, and what it may do.
Everything on the browser side of Wajub runs on one short lived string: the session token. This page covers where it comes from, what it replaces, and why the key that creates it must never leave your server.
Three credentials, three places
The prefix of a Wajub key tells you where the key is allowed to live. Live keys start with sk. or
pk., sandbox keys with sk_test. or pk_test..
| Credential | Looks like | Lives in | Can do |
|---|---|---|---|
| Publishable key | pk. or pk_test. | Browser, your HTML | Create a session, nothing else |
| Secret key | sk. or sk_test. | Server, environment variable | Everything on the API |
| Session token | authorization_token | Browser, as sessionId | Pay one payment, once |
The session token is what makes the other two unnecessary in the browser. It is scoped to a single payment, it carries no account access, and it dies with that payment.
A secret key in a browser is refused and reported
A secret key must never be used from a browser. When Wajub detects one, the API refuses it with
403 and alerts the key's owner by email. The SDK refuses it before that, with a
secret_key_in_browser error. Neither is a safety net you should ever reach.
The flow that is correct
Two steps, in this order, every time.
- Your server calls
POST /paymentswith the secret key and gets back anauthorization_token. - Your browser receives that token, and nothing else, and passes it as
sessionId.
curl https://api.wajub.com/payments \
-H "Authorization: sk_test.xxxxxxxxxxxxxxxx…" \
-H "Content-Type: application/json" \
-d '{
"amount": 35000,
"currency": "XOF",
"reference": "ORDER-123",
"customer": { "email": "[email protected]" }
}'The response carries three things worth keeping.
| Field | What it is for |
|---|---|
authorization_token | The browser's sessionId. Send this one down |
authorization_url | The hosted page, for a redirect checkout |
transaction.id | Your reconciliation key when the webhook lands |
const { sessionId } = await fetch('/api/checkout/session', { method: 'POST' })
.then((r) => r.json());
await mount('#checkout', { sessionId });Before the order exists
Payment fields shown while the buyer is still on the checkout come before the order. Create their
session with deferred: true: the payment is only prepared, stays out of your payments and sends
no webhook until your server activates it with the final total and the customer.
Before the order exists walks
through the three calls.
Creating a session from the browser
Wajub(publishableKey).createPayment() exists and works with a sandbox key: in 1.5.0 a live key,
pk.…, is read as a session id, so in live the session is created on your server. It is the right
tool for a prototype or a demo page with a fixed price. It is the wrong tool for a shop, because the amount
is then decided by code the customer controls.
const client = Wajub('pk_test.xxxxxxxxxxxxxxxx…');
const { sessionId } = await client.createPayment({
amount: 35000,
currency: 'XOF',
customer: { email: '[email protected]' },
});
await client.mount('#checkout');The price is part of the trust boundary
A publishable key cannot read your account, but it can open a payment for any amount the page asks for. Anything a customer could profit from changing belongs on your server.
What the token may do
The session token authorises exactly one payment, and the runtime is what enforces it.
- It mounts the checkout, opens the overlay, or drives the field components.
- It reads the session preview through
fetchSession(sessionId). - On a prepared payment, it shows the ways to pay and charges nothing: every charge answers
409until your server activates the payment. Activation keeps the token. - It stays valid while the payment is not terminal, and stops shortly after
succeeded,failed,expiredorcancelled. - It survives a remount, so a component that unmounts and comes back reuses the same token.
- It lives as long as the payment: 24 hours by default, or the
expires.inminutes you set onPOST /payments(5 to 43 200). Past that the payment expires,onExpiredfires on the checkout, and a payment field rejects withsession_expired. - Payment attempts on one session are rate limited. Past the limit, the attempt is refused with
rate_limiteduntil a short wait has passed.
Mounting a token that has stopped calls onLoadError with session_terminal_expired, and a token
Wajub does not know calls it with session_not_found. The embed itself stays empty, which is why
that callback is worth wiring even on a page you think cannot reach it. Until the token stops, a
checkout mounted on a finished payment reports the outcome instead, through onSuccess, onError,
onExpired or onCancel.
The callback URL
callback is a redirect destination, so it only matters for the redirect flow. Pass a plain HTTPS
base URL with no query string of your own. Wajub appends its own.
| Query param | Values |
|---|---|
status | succeeded, cancelled, failed, expired |
reference | Wajub's id of the payment, the one GET /payments/{id} takes, when available |
trxref | Your own reference, when available |
Every return carries reference and trxref, a failed payment's included: that one used to carry
status alone.
https://shop.example.com/order/complete?status=succeeded&reference=trx_CSUGajfv9xh0XQ5wu2lx&trxref=ORDER-123status=succeeded is a hint, not a receipt
It is a query string on a URL the payer can edit. Ship the order when payment.succeeded
arrives on your endpoint, or when a server side
GET /payments/{id} says so.
An embed never leaves your page, so callback does nothing there. Use onSuccess for the
interface and the webhook for the truth.
Multi domain shops
A single domain needs no configuration. When your checkout runs on a second domain, name the canonical one explicitly.
await mount('#checkout', { sessionId, embedOrigin: 'https://shop.example.com' });
const factory = await components(sessionId, {
componentOrigin: 'https://shop.example.com',
});Before you go live
| Rule | Why |
|---|---|
HTTPS on your site and on callback | Payment iframes and redirects refuse plain HTTP |
sk. only in server environment variables | Never in a bundle, never in a PUBLIC_ variable |
Only authorization_token reaches the browser | It is the one credential with nothing to lose |
| Mount through the SDK | The checkout only runs when the SDK mounts it |
| Confirm with a webhook | onSuccess is a browser event, and browsers close |