我正在尝试使用the dbus-rs库来使用GetSettings方法从NetworkManager获取连接信息。我用D-Feet试用了一个签名为GetSettings() -> (Dict of {String, Dict of {String, Variant} } settings)的函数，D-Feet返回的数据如下：
{'802-11-wireless': {'mac-address': [228, 179, 24, 77, 64, 139],
'mac-address-blacklist': [],
'mode': 'infrastructure',
'security': '802-11-wireless-security',
'seen-bssids': ['02:1D:AA:80:1B:DA', '02:1D:AA:80:1D:12'],
'ssid': [80,
108,
111,
117,
103,
104,
32,
87,
97,
121,
32,
67,
97,
102,
101]},
'802-11-wireless-security': {'auth-alg': 'open',
'group': [],
'key-mgmt': 'wpa-psk',
'pairwise': [],
'proto': []},
'connection': {'id': 'Plough Way Cafe',
'permissions': [],
'secondaries': [],
'timestamp': 1479304123,
'type': '802-11-wireless',
'uuid': 'ff9b7028-0911-491a-bfe8-53cba76069da'},
'ipv4': {'address-data': [],
'addresses': [],
'dns': [],
'dns-search': [],
'method': 'auto',
'route-data': [],
'routes': []},
'ipv6': {'address-data': [],
'addresses': [],
'dns': [],
'dns-search': [],
'method': 'auto',
'route-data': [],
'routes': []}}
和我的代码：
extern crate dbus;
fn main() {
let message = dbus::Message::new_method_call("org.freedesktop.NetworkManager",
"/org/freedesktop/NetworkManager/Settings/0",
"org.freedesktop.NetworkManager.Settings.\
Connection",
"GetSettings")
.unwrap();
let response = dbus::Connection::get_private(dbus::BusType::System)
.unwrap()
.send_with_reply_and_block(message, 2000)
.unwrap();
println!("{:?}", response);
let test: dbus::arg::Dict<&str, dbus::arg::Dict<&str, dbus::arg::Variant<()>, _>, _> =
response.get1().unwrap();
println!("{:?}", test);
}
会导致此错误：
error[E0277]: the trait bound `(): dbus::arg::Get<'_>` is not satisfied
--> src/main.rs:20:18
|
20 | response.get1().unwrap();
| ^^^^ the trait `dbus::arg::Get<'_>` is not implemented for `()`
|
= note: required because of the requirements on the impl of `dbus::arg::Get<'_>` for `dbus::arg::Variant<()>`
= note: required because of the requirements on the impl of `dbus::arg::Get<'_>` for `dbus::arg::Dict<'_, &str, dbus::arg::Variant<()>, dbus::arg::Iter<'_>>`
= note: required because of the requirements on the impl of `dbus::arg::Get<'_>` for `dbus::arg::Dict<'_, &str, dbus::arg::Dict<'_, &str, dbus::arg::Variant<()>, dbus::arg::Iter<'_>>, dbus::arg::Iter<'_>>`
如何获取连接信息？
我认为Variant的重点在于它可以容纳不同类型的数据吗？我做错了什么？
如果我将Variant类型()替换为&str，则会打印出Dict(Iter("Unknown?!", "Unknown?!", "Unknown?!", "Unknown?!", "Unknown?!"), PhantomData)。什么是Unknown?!值？
API for Dict也说明了
从迭代器创建一个新的
Dict。附加时会消耗迭代器。
我应该如何/应该使用它？我确实设法取得了一些进展，也许是天真的？
我的代码现在看起来像这样：
extern crate dbus;
extern crate network_manager;
#[derive(Default, Debug)]
struct Connection {
path: String,
id: String,
uuid: String,
ssid: String,
interface: String,
security: String,
psk: String, // Only used when creating a new connection
}
fn main() {
let connection = Connection {
path: "/org/freedesktop/NetworkManager/Settings/0".to_string(),
..Default::default()
};
let message = dbus::Message::new_method_call("org.freedesktop.NetworkManager",
connection.path.clone(),
"org.freedesktop.NetworkManager.Settings.\
Connection",
"GetSettings")
.unwrap();
let response = dbus::Connection::get_private(dbus::BusType::System)
.unwrap()
.send_with_reply_and_block(message, 2000)
.unwrap();
let mut outer_array_iter = response.iter_init().recurse(97).unwrap();
loop {
let mut outer_dict_iter = outer_array_iter.recurse(101).unwrap();
outer_dict_iter.next();
let mut inner_array_iter = outer_dict_iter.recurse(97).unwrap();
loop {
let mut inner_dict_iter = inner_array_iter.recurse(101).unwrap();
let key = inner_dict_iter.read::<&str>().unwrap();
match key {
"id" => {
let val: dbus::arg::Variant<&str> = inner_dict_iter.read().unwrap();
println!("id {:?}", val);
}
"uuid" => {
let val: dbus::arg::Variant<&str> = inner_dict_iter.read().unwrap();
println!("uuid {:?}", val);
}
"ssid" => {
let val: dbus::arg::Variant<dbus::arg::Array<i32, _>> = inner_dict_iter.read()
.unwrap();
println!("ssid {:?}", val);
}
"type" => {
let val: dbus::arg::Variant<&str> = inner_dict_iter.read().unwrap();
println!("interface {:?}", val);
}
"security" => {
let val: dbus::arg::Variant<&str> = inner_dict_iter.read().unwrap();
println!("security {:?}", val);
}
_ => (),
}
if !(inner_array_iter.next()) {
break;
}
}
if !(outer_array_iter.next()) {
break;
}
}
println!("{:?}", connection);
}
打印出来：
id Variant("Plough Way Cafe")
uuid Variant("e078808e-626f-4be9-bbb4-5e48b1d626de")
interface Variant("802-11-wireless")
ssid Variant(Array(Iter("u8", "u8", "u8", "u8", "u8", "u8", "u8", "u8"), PhantomData))
security Variant("802-11-wireless-security")
Connection { path: "/org/freedesktop/NetworkManager/Settings/0", id: "", uuid: "", ssid: "", interface: "", security: "", psk: "" }
如何从Variant和connection结构中获取数据？有没有更好的方法来使用迭代器，因为这感觉非常脆弱？
答案 0 :(得分：0)
以下是修改第一个示例的方法：
let test: dbus::arg::Dict<&str, dbus::arg::Dict<&str, dbus::arg::Variant<dbus::arg::Iter>, _>, _> =
response.get1().unwrap();
for (k1, v1) in test {
println!("outer key = {:?}", k1);
for (k2, v2) in v1 {
println!(" inner key = {:?}, inner type = {:?}, string value = {:?}", k2, v2, v2.0.clone().get::<&str>());
}
}
如果您在获得变体时不知道变体中的内容，则需要使用Variant<Iter>。然后，您必须使用get::<&str>(), get::<u32>()等来检索变体中的实际值。