Derive Macro TryFromMap 

#[derive(TryFromMap)]
{
    // Attributes available to this derive:
    #[serde_json]
}

Derive TryFrom<HashMap<String, String>> for a struct.

This macro will generate an implementation of TryFrom<HashMap<String, String>> for the annotated struct. It will attempt to parse each field from the map, and return an error if any field is missing or cannot be parsed. Fields of type Option<T> are supported, and will be set to None if the field is missing from the map.

Supports structs with named fields that either impl FromStr or serde::Deserialize. Fields that implement serde::Deserialize can be annotated with #[serde_json] to parse the value as JSON.

Example

use try_from_map::TryFromMap;

#[derive(TryFromMap, Debug)]
struct Foo {
   a: i32,
   b: f32,
   c: Option<bool>,
   #[serde_json] // Parse as JSON as Vec<f64> does not impl FromStr
   d: Vec<f64>,
}


let map = std::collections::HashMap::from([
    ("a".to_string(), "42".to_string()),
    ("b".to_string(), "3.14".to_string()),
    ("d".to_string(), "[3.14, 2.71]".to_string()),
]);

let foo = Foo::try_from(map).unwrap();

println!("{:?}", foo);

assert_eq!(foo.a, 42);
assert_eq!(foo.b, 3.14);
assert_eq!(foo.c, None);
assert_eq!(foo.d, vec![3.14, 2.71]);