How to pass the value stored in variable to json file

Hi,

I am new to gatling…Can anybody please help me for this problem…

Here is my code…

.exec(http(“PUT_call”)
.put("/users/posts/${postid}")
.headers(put_header)
.body(RawFileBody(“create_post.json”)).asJSON)

And the json file details are:

create_post.json

{
“title”: “Post with gatlingt”,
“content”: “Content of post”,
“author”:"${user}
}

So for this author:${user} I have to pass the value from response of another request…For that already I saved that value using saveAs method…So ${user} value is ready to use

But how to pass the value stored in variable to json file…??Please help me…

Use the correct function. RawFileBody is for files that need to be sent as-is. ELFileBody is for Expression Language templates that contain embedded variables.