Get reference to a specific struct in a Vector to modify it

Question

I'm starting my first project in Rust. I try to make a Zwave crate.

I'm stuck with the problem of ref sharing. For now, the code is divided in 3 structs:

Network, which contains global Zwave network information:

struct Network{
    name: &'static str,
    home_id: u32,
    nodes: Vec<Node>,
}

A Node structure which contains information of a specific node:

struct Node{
    pub name: &'static str,
    home_id: u32,
    node_id: u8,
    devices: Vec<Device>,
}

And a device storing data about sensor or other Zwave device:

struct Device{
    name: &'static str,
    class: DeviceClass,
}

What I'm trying to do is get the reference of a specific node in order to modify devices in it (Add, remove...), but it always lead to the same error when I try to add device after getting reference of the node: Cannot borrow as mutable

The add_device function looks like this:

pub fn add_device(&mut self, name: &'static str ) -> Result<bool, &'static str>{
    self.devices.push(Device::new(name)?);
    Ok(true)
}

This is how I try to get reference in Network struct:

pub fn get_node(&self, node_name : String ) -> Result<&Node, &'static str>{
    for node in &self.nodes{
        if node.name == node_name{
            return Ok(node);
        }
    }
    Err("Node not find")
}

I have try with Mutex, Rc, tried to implement copy/clone but never reach what I want. Can you help me?

Answer 1

consider using (&mut self) as function argument and the return type to a mutable reference to Node (Result<&mut Node, &'static str>) and then you can iterate the nodes Vec with iter_mut() to get a mutable reference to the nodes like:

for node in self.nodes.iter_mut() {
    if node.name == node_name{
        return Ok(node);
    }
}
Err("Node not find")

and that should work for you