So this is two questions at once. Let's start with the second one.
Why is the string passed in """json""" such a manner?
Scala allows special syntax for multiline string literals (or strings containing newlines, quotation marks and so on).
So you can do
val s = """Welcome home!
How are you today?"""
Now back to the main question
How can I pass lat, long and radius as arguments in the postData field?
I suppose you are in this situation:
val lat = "39.6270025"
val long = "-90.1994042"
And you want to pass that into the postData
function, mixed with some other maybe fixed strings.
Well another feature Scala gives is so-called string interpolation
.
Easy example
val name = "Mark" // output on the REPL would be: name: String = Mark
val greeting = s"Hello $name!" // output on the REPL would be: greeting: String = Hello Mark!
So in your case you could do the same
val result = Http("http:xxxx/xxx/xxxxx")
.postData(s"""{"latitude":$lat,"longitude":$long,"radius":"0"}""")
.asString