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# Method name: login(email: string, password: string)

# Method package: wixMembersBackend

# Method menu location: wixMembersBackend --> Authentication --> login

# Method Link: https://dev.wix.com/docs/velo/apis/wix-members-backend/authentication/login.md

# Method Description:

Logs a registered member in with an email and password.


The `login()` function returns a Promise that resolves to a session token
used to log a member in to your site.

The `login()` function only works with existing members. To register a new member use 
the [`register()` function](#register).

To complete the login,
the returned session token must be applied using the
[`applySessionToken()`](https://dev.wix.com/docs/velo/api-reference/wix-members-frontend/authentication/apply-session-token.md)
function (from wix-members-frontend) in page code.



# Method Code Examples:

*** Note: do not assume any prop names or enum values other than the ones in the example.

## Generate a session token if a valid email and password are provided

```javascript
import { Permissions, webMethod } from 'wix-web-module';
import { authentication } from 'wix-members-backend';

export const myLoginFunction = webMethod(Permissions.Anyone, (email, password) => {
  return authentication.login(email, password)
    .then((sessionToken) => {
      return sessionToken;
    })
    .catch((error) => {
      console.error(error);
    });
});

/* Promise resolves to a session token:
 * "JWS.eyJraWQiOiJQSXpvZGJiQiIsImFsZyI6IkhTMjU2In0.eyJkYXRhIjoie1wiaWRcIjpcIjg4MzFlZWQ2LTkyOGUtNGY4NS1iODBhLWUxZTQ4ZmI3YzRmZFwiLFwiY29sbGVjdGlvbklkXCI6XCI5YmVjNThlNi02NDExLTQ5OTEtOGU1ZC0wYWRhOTE4MmI5NWVcIixcIm1ldGFTaXRlSWRcIjpcIjFmZjQ2YTk2LWRlYTYtNDlkYS04M2JhLTUxNjRmYjYyZDgzOVwiLFwib3duZXJcIjpmYWxzZSxcImNyZWF0aW9uVGltZVwiOjE2MjI0MTUxMTMyNjYsXCJleHBpcmVzSW5cIjoxMjA5NjAwMDAwLFwiZXhwaXJhdGlvblRpbWVcIjoxNjIyNDE1MjMzMjY2LFwibGFzdFJlZnJlc2hlZFwiOjAsXCJhZG1pblwiOmZhbHNlfSIsImlhdCI6MTYyMjQxNTExM30.CFJTkyDaF6LypH8UuNm74qgZMxTKFgB1ZnzsemhY_KY"
 */
```

## Log a member in after they provide an email and password

```javascript
/****************************
 * Backend code - login.web.js *
 ***************************/

import { Permissions, webMethod } from 'wix-web-module';
import { authentication } from 'wix-members-backend';

export const getLoginToken = webMethod(Permissions.Anyone, async (email, password) => {

  let sessionToken;

  try {
    sessionToken = await authentication.login(email, password);

    // If the promise resolves, the member is authenticated and can be logged in
    return {
      sessionToken: sessionToken,
      approved: true
    };
  } catch (error) {
    // If the promise is rejected, the member is not authenticated
    // and cannot be logged in
    console.error(error);
    return {
      approved: false,
      error: error
    };
  }
});

/*************
* Page code *
************/

import { getLoginToken } from 'backend/login.web';
import { authentication } from 'wix-members-frontend';

$w('#login').onClick(async () => {
  const email = $w('#email').value;
  const password = $w('#password').value

  // Call the backend function to get the session token
  const loginResult = await getLoginToken(email, password);

  if (loginResult.approved) {
    // If approved, log the member in using the returned session token
    authentication.applySessionToken(loginResult.sessionToken);
  } else {
    // If not approved, log a message
    console.error('Login not approved.');
  }
});
```

---