jsonhttprustrust-rocket

How can I respond to a POST request containing JSON data with Rocket?


I'm trying to create a backend using the Rocket crate:

fn main() {
    rocket::ignite().mount("/", routes![helloPost]).launch();
}

#[derive(Debug, PartialEq, Eq, RustcEncodable, FromForm)]
struct User {
    id: i64,
    USR_Email: String,
    USR_Password: String,
    USR_Enabled: i32,
    USR_MAC_Address: String
}

#[post("/", data = "<user_input>")]
fn helloPost(user_input: Form<User>) -> String {
    println!("print test {}", user_input);
}

When I run cargo run everything works but, when I send a POST request with postman for testing, I get this error:

POST /:
    => Matched: POST / (helloPost)
    => Warning: Form data does not have form content type.
    => Outcome: Forward
    => Error: No matching routes for POST /.
    => Warning: Responding with 404 Not Found catcher.
    => Response succeeded.

I've set the header content type to JSON and with other languages that works, but with Rocket I can't get it to work.

This is my JSON body:

{
    "USR_Email": "test@test.it",
    "USR_Password": "500rockets",
    "USR_Enabled": 0,
    "USR_MAC_Address": "test test"
}

How can fix this?


Solution

  • Adapted basically verbatim from the rocket_contrib example.

    Cargo.toml:

    <snip>
    
    [dependencies]
    rocket = "0.4.2"
    rocket_contrib = "0.4.2"
    serde = { version = "1.0", features = ["derive"] }
    serde_json = "1.0"
    

    src/main.rs:

    #![feature(proc_macro_hygiene, decl_macro)]
    
    #[macro_use] extern crate rocket;
    use rocket_contrib::json::Json;
    use serde::Deserialize;
    
    #[derive(Debug, PartialEq, Eq, Deserialize)]
    struct User {
        id: i64,
        USR_Email: String,
        USR_Password: String,
        USR_Enabled: i32,
        USR_MAC_Address: String
    }
    
    #[post("/", format = "json", data = "<user_input>")]
    fn helloPost(user_input: Json<User>) -> String {
        format!("print test {:?}", user_input)
    }
    
    fn main() {
        rocket::ignite().mount("/hello", routes![helloPost]).launch();
    }
    
    

    A few things of note:

    Testing with curl:

    $ curl -H 'Content-Type: application/json' \
        --data '{"id": 123, "USR_Email": "abc@example.com", "USR_Password": "hunter2", "USR_Enabled": 1, "USR_MAC_Address": "ff:ff"}' \
        http://localhost:8000/hello
    print test Json(User { id: 123, USR_Email: "abc@example.com", USR_Password: "hunter2", USR_Enabled: 1, USR_MAC_Address: "ff:ff" })
    

    Note that every field in your User has to be present in JSON, or 400 Bad Request will be raised. You might want to use Option<> for some of these.