# Why failed to set request.body.query in supergraph\_service Rhai script

**URL:** https://community.apollographql.com/t/why-failed-to-set-request-body-query-in-supergraph-service-rhai-script/7907
**Category:** Router
**Tags:** router, federation, rhai
**Created:** [October 23, 2024, 8:02am UTC](https://community.apollographql.com/t/why-failed-to-set-request-body-query-in-supergraph-service-rhai-script/7907 "2024-10-23T08:02:28Z")
**Posts on this page:** 1
**Page:** 1

<div class="post-metadata">

### Author: ![Yongho\_Jung](https://sea1.discourse-cdn.com/flex019/user_avatar/community.apollographql.com/yongho_jung/32/5337_2.png) [@Yongho\_Jung](https://community.apollographql.com/u/Yongho_Jung)
#### Post date: [October 23, 2024, 8:02am UTC](https://community.apollographql.com/t/why-failed-to-set-request-body-query-in-supergraph-service-rhai-script/7907/1 "2024-10-23T08:02:28Z")

</div>

according to rhai API document. ([https://www.apollographql.com/docs/graphos/reference/router/rhai#requestbodyquery](https://www.apollographql.com/docs/graphos/reference/router/rhai#requestbodyquery))  
‘request.body.query’ is modifiable in rhai supergraph\_service function.  
so, I modified ‘request.body.query’ like this.

fn supergraph\_service(service) {  
service.map\_request(|request| {  
print(`${request.body.query}`);  
request.body.query=“query invalid { \_typnam }}”;  
print(`${request.body.query}`);  
});  
}

but, just ‘request.body.query’ is modified locally(in super\_graph function only), subgraph query is still not changed.  
Why not changed query in subgraph?