Created a user pool client using Cognito Identity Provider Client SDK for JavaScript v3, but can't fetch token using (client_credentials) grant type - oauth-2.0

Question

Created a user pool client using Cognito Identity Provider Client SDK for JavaScript v3
npm install #aws-sdk/client-cognito-identity-provider.
The following code shows how I created the resources server and the user pool client, using the mentioned👆 SDK...
let poolName = 'UserPool';
const client =new CognitoIdentityProviderClient({
region: process.env.COGNITO_AWS_REGION
});
// create resource server
const createResourceServerCommand = new CreateResourceServerCommand({
Name: poolName,
UserPoolId: UserPool.Id,
Identifier: 'https://localhost:8080/api/v2',
Scopes: [
{
ScopeName: 'access',
ScopeDescription: 'General access to API'
}
]
});
const { ResourceServer } = await client.send(createResourceServerCommand);
// create the user pool client
const createUserPoolClientCommand = new CreateUserPoolClientCommand({
ClientName: 'Default',
UserPoolId: UserPool.Id,
ExplicitAuthFlows: ['USER_PASSWORD_AUTH'],
GenerateSecret: true,
AllowedOAuthFlows: ['client_credentials'],
SupportedIdentityProviders: ['COGNITO'],
AllowedOAuthScopes: [ 'https://localhost:8080/api/v2/access' ]
});
const { UserPoolClient } = await client.send(createUserPoolClientCommand);
...but, I can't fetch tokens using the grant type client_credentials. Therefore getting the following error.
{
"error": "invalid_grant"
}
However, if I use AWS console to navigate to the user pool > Client > Edit the hosted UI and click on the save button without making any changes...
... I am able to fetch a token using the client_credentials grant type.
Is there any setting that I might be missing in the above code that AWS console is setting? I need the following code to automate the creation of user pools.

Answer 1

When I switched to the old I noticed this notification
Apparently, Oauth flows are not enabled by default. Hence adding the following attribute to the CreateUserPoolClientCommandInput object AllowedOAuthFlowsUserPoolClient: true enables it. Hope this helps some newbie like me out there.