correct way Mule OAuth2 client credentials refresh token - oauth-2.0

Question

I am using mule to connect/consume some services. Authentication is OAuth2 client-credential.
What is best way to refresh the token?
One way could be checking http.status like
refreshTokenWhen="#[message.inboundProperties['http.status'] == 401]"
but I am not very happy with that since it should fail once to refresh the token.
Is there anyway to refresh the token based on expire time?
my sample code:
<mule xmlns:tracking="http://www.mulesoft.org/schema/mule/ee/tracking" xmlns:scripting="http://www.mulesoft.org/schema/mule/scripting" xmlns:metadata="http://www.mulesoft.org/schema/mule/metadata" xmlns:oauth2="http://www.mulesoft.org/schema/mule/oauth2" xmlns:http="http://www.mulesoft.org/schema/mule/http"
xmlns="http://www.mulesoft.org/schema/mule/core" xmlns:doc="http://www.mulesoft.org/schema/mule/documentation"
xmlns:spring="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.mulesoft.org/schema/mule/http http://www.mulesoft.org/schema/mule/http/current/mule-http.xsd
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-current.xsd
http://www.mulesoft.org/schema/mule/core http://www.mulesoft.org/schema/mule/core/current/mule.xsd
http://www.mulesoft.org/schema/mule/oauth2 http://www.mulesoft.org/schema/mule/oauth2/current/mule-oauth2.xsd
http://www.mulesoft.org/schema/mule/scripting http://www.mulesoft.org/schema/mule/scripting/current/mule-scripting.xsd
http://www.mulesoft.org/schema/mule/ee/tracking http://www.mulesoft.org/schema/mule/ee/tracking/current/mule-tracking-ee.xsd">
<http:request-config name="HTTP_Request_Configuration" protocol="HTTPS" host="${remote.host}" port="${remote.port}" basePath="${remote.path}" doc:name="HTTP Request Configuration">
<oauth2:client-credentials-grant-type clientId="${clientid}" clientSecret="${clientSecret}" tokenManager-ref="Token_Manager_Config">
<oauth2:token-request tokenUrl="${remote.tokenUrl}" refreshTokenWhen="#[message.inboundProperties['http.status'] == 401 ]">
<oauth2:token-response accessToken="#[json:access_token]" expiresIn="#[json:expires_in]"/>
</oauth2:token-request>
</oauth2:client-credentials-grant-type>
</http:request-config>
<oauth2:token-manager-config name="Token_Manager_Config" doc:name="Token Manager Config"/>

Answer 1

There is a chache scope in mule, you can keep your gettoken flow in cache scope and you can specify the expire time, till that time it will use the cached token, when ever it gets expire then it will invoke the get token flow and it will store the new token in your cache.
Sample code:
<ee:object-store-caching-strategy name="Caching_Strategy" doc:name="Caching Strategy">
<managed-store storeName="myManagedStore" maxEntries="1" entryTTL="${token.expiretime}" expirationInterval="${token.expireinterval}"/>
</ee:object-store-caching-strategy>
<ee:cache cachingStrategy-ref="Caching_Strategy" doc:name="Cache">
<flow-ref name="getTokenFlow" doc:name="getTokenFlow"/>
</ee:cache>
Check more documentation at below link:
https://docs.mulesoft.com/mule-user-guide/v/3.7/cache-scope