# I have a react app, and I want to implement the SSO feature. But I always get a nonce error

**URL:** <https://meta.discourse.org/t/i-have-a-react-app-and-i-want-to-implement-the-sso-feature-but-i-always-get-a-nonce-error/269393>\
**Category:** Development\
**Tags:** sso\
**Created:** [June 23, 2023, 2:01pm UTC](https://meta.discourse.org/t/i-have-a-react-app-and-i-want-to-implement-the-sso-feature-but-i-always-get-a-nonce-error/269393 "2023-06-23T14:01:27Z")\
**Posts on this page:** 1\
**Showing post:** 1

<div class="post-metadata">

**Author:** ![Mohammad\_Ghandour](https://sea3.discourse-cdn.com/meta/user_avatar/meta.discourse.org/mohammad_ghandour/32/322040_2.png) [@Mohammad\_Ghandour](https://meta.discourse.org/u/Mohammad_Ghandour)\
**Post date:** [June 23, 2023, 2:01pm UTC](https://meta.discourse.org/t/i-have-a-react-app-and-i-want-to-implement-the-sso-feature-but-i-always-get-a-nonce-error/269393/1 "2023-06-23T14:01:27Z")

</div>

So I already checked the `enable discourse connect`, and specified the `discourse connect url`  
and set the `discourse connect secret` successfully.  
On the page of the `discourse connect url`, I’m doing the following :

```js
function rediretUserToDiscourse(user) {
        const url = new URL(window.location)
        const searchParams = new URLSearchParams(url.search);
        const ssoValue = searchParams.get("sso");
        const decodedSSOValue = window.atob(ssoValue);
        const queryParams = decodedSSOValue.split("&");

        let nonce = null;
        for (let param of queryParams) {
            const [key, value] = param.split("=");
            if (key === "nonce") {
                nonce = value;
                break;
            }
        }

        if (user) {
            const payload = `nonce=${nonce}&name=${user.username}&username=${user.username}&email=${user.email}&external_id=${user.id}&avatar_url=${user.avatar}`;

            const encodedPayload = window.btoa(JSON.stringify(payload));
            const secret = "discourse_connect_secret";

            hmac(encodedPayload, secret, HmacAlgorithms.HmacSHA256, Encoders.hex)
                .then(signature => {
                    if (signature) {
                        const discourseLoginURL = `https://community.mydomaine.co/session/sso_login?sso=${encodedPayload}&sig=${signature}`;
                        window.location.href = discourseLoginURL;
                    }
                });
        }
    };

```

Everything works perfectly (the signature is valid, and it redirects me to the discourse). But I keep getting the following error : `Nonce is incorrect, was generated in a different browser session, or has expired`. I spent hours of searching for a solution in here, google, and chatGPT (cz why not :p) and I still didn’t found a solution.

Does anyone knows how can I fix it please ?

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