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deserialization json rust serde

How can I deserialize JSON with a top-level array using Serde?

I have a some JSON data that is returned from a web service. The JSON is a top-level array:

[
{
"data": "value1"
},
{
"data": "value2"
},
{
"data": "value3"
}
]

Using serde_derive to make structs I can can deserialize the data contained within the array, however, I am unable to get Serde to deserialize the top-level array.

Am I missing something, or can Serde not deserialize top level-arrays?

You can simply use a Vec:

use serde::{Serialize, Deserialize};
#[derive(Serialize, Deserialize, Debug)]
struct Foo {
data: String,
}
fn main() -> Result<(), serde_json::Error> {
let data = r#"[
{
"data": "value1"
},
{
"data": "value2"
},
{
"data": "value3"
}
]"#;
let datas: Vec<Foo> = serde_json::from_str(data)?;
for data in datas.iter() {
println!("{:#?}", data);
}
Ok(())
}


If you wish, you could also use transparent:

#[derive(Serialize, Deserialize, Debug)]
#[serde(transparent)]
struct Foos {
foos: Vec<Foo>,
}
let foos: Foos = serde_json::from_str(data)?;

This allows to encapsulate your data with your type.