serde

How can I apply a transformation to a field before serialization? For example, how can I ensure that the fields lat and lon in this struct definition are rounded to at most 6 decimal places before being serialized? #[derive(Debug, Serialize)] struct NodeLocation { #[serde(rename = "nodeId")] id: u32, lat: f32, lon: f32, } krdln The serialize_with attribute You can use the serialize_with attribute to provide a custom serialization function for your field: #[macro_use] extern crate serde_derive; extern crate serde; use serde::Serializer; fn round_serialize<S>(x: &f32, s: S) -> Result<S::Ok, S:

I'm trying to solve the problem of serializing and deserializing Box<SomeTrait> . I know that in the case of a closed type hierarchy, the recommended way is to use an enum and there are no issues with their serialization, but in my case using enums is an inappropriate solution. At first I tried to use Serde as it is the de-facto Rust serialization mechanism. Serde is capable of serializing Box<X> but not in the case when X is a trait. The Serialize trait can’t be implemented for trait objects because it has generic methods. This particular issue can be solved by using erased-serde so

I want to use Serde to create an array with error messages as well as proper objects: extern crate serde; // 1.0.70 #[macro_use] extern crate serde_derive; // 1.0.70 extern crate serde_json; // 1.0.24 #[derive(Serialize, Deserialize, Debug)] pub struct MyError { error: String, } #[derive(Serialize, Deserialize, Debug)] pub struct MyAge { age: i32, name: String, } fn get_results(ages: Vec<i32>) -> Vec<MyAge> { let mut results = vec![]; for age in ages { if age < 100 && age > 0 { results.push(MyAge { age: age, name: String::from("The dude"), }); } else { results.push(MyError { error: String:

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 struct s 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? Stargateur You can use a Vec : extern crate serde; extern crate serde_json; #[macro_use] extern crate serde_derive; use serde_json::Error; #[derive(Serialize, Deserialize, Debug)] struct Foo { data:

I'm using serde and serde_json 1.0 to decode data from a base64 string: fn from_base64_str<T: Deserialize>(string: &str) -> T { let slice = decode_config(string, URL_SAFE).unwrap(); serde_json::from_slice(&slice).unwrap() } When I compile, I got this: error[E0106]: missing lifetime specifier --> src/main.rs:6:23 | 6 | fn from_base64_str<T: Deserialize>(string: &str) -> T { | ^^^^^^^^^^^ expected lifetime parameter Checking the serde doc, Deserialize is defined as: pub trait Deserialize<'de>: Sized { So I added the lifetime: fn from_base64_str<'de, T: Deserialize<'de>>(string: &str) -> T { let

I'm using Serde to deserialize an XML file which has the hex value 0x400 as a string and I need to convert it to the value 1024 as a u32 . Do I need to implement the Visitor trait so that I separate 0x and then decode 400 from base 16 to base 10? If so, how do I do that so that deserialization for base 10 integers remains intact? The deserialize_with attribute The easiest solution is to use the Serde field attribute deserialize_with to set a custom serialization function for your field. You then can get the raw string and convert it as appropriate : use serde::{de::Error, Deserialize,