Lookup json fields in rust - https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&gist=b244a3aea4e73d5958b5527a21f0a51f

main.rs

use serde_json::Value;

fn get_value<'a>(j: &'a Value, p: &str) -> Option<&'a Value> {
    let keys = p.split('/').collect::<Vec<&str>>();
    let mut current_value = j;

    for key in keys {
        current_value = match current_value.get(key) {
            Some(value) => value,
            None => return None,
        };
    }

    Some(current_value)
}

#[cfg(test)]
mod tests {
    use super::*;
    use serde_json::json;

    #[test]
    fn test_get_value() {
        let data = json!({
            "user": {
                "name": "John Cena",
                "age": 40,
                "addresses": {
                    "home": {
                        "street": "123 Sesame St",
                    }
                }
            }
        });

        assert_eq!(get_value(&data, "user/name"), Some(&json!("John Cena")));
        assert_eq!(get_value(&data, "user/age"), Some(&json!(40)));
        assert_eq!(
            get_value(&data, "user/addresses/home/street"),
            Some(&json!("123 Sesame St"))
        );
        assert_eq!(get_value(&data, "user/addresses/home/zip"), None);
    }
}