1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547
use dbus::arg::ArgType;
use derive_is_enum_variant::is_enum_variant;
use enum_kinds::EnumKind;
use from_variants::FromVariants;
use std::collections::HashMap;
/// Holds a dynamically-typed metadata value.
///
/// You will need to type-check this at runtime in order to use the value.
#[derive(Debug, PartialEq, Clone, EnumKind, is_enum_variant, FromVariants)]
#[enum_kind(ValueKind)]
pub enum Value {
/// Value is a string.
String(String),
/// Value is a 16-bit integer.
I16(i16),
/// Value is a 32-bit integer.
I32(i32),
/// Value is a 64-bit integer.
I64(i64),
/// Value is an unsigned 8-bit integer.
U8(u8),
/// Value is an unsigned 16-bit integer.
U16(u16),
/// Value is an unsigned 32-bit integer.
U32(u32),
/// Value is an unsigned 64-bit integer.
U64(u64),
/// Value is a 64-bit float.
F64(f64),
/// Value is a boolean.
Bool(bool),
/// Value is an array of other values.
Array(Vec<Value>),
/// Value is a map of other values.
Map(HashMap<String, Value>),
/// Unsupported value type.
#[from_variants(skip)]
Unsupported,
}
impl Value {
/// Returns a simple enum representing the type of value that this value holds.
///
/// # Examples
///
/// ```rust
/// # use mpris::Metadata;
/// # let metadata = Metadata::new("1234");
/// # let key_name = "foo";
/// use mpris::MetadataValueKind;
/// if let Some(value) = metadata.get(key_name) {
/// match value.kind() {
/// MetadataValueKind::String => println!("{} is a string", key_name),
/// MetadataValueKind::I16 |
/// MetadataValueKind::I32 |
/// MetadataValueKind::I64 |
/// MetadataValueKind::U8 |
/// MetadataValueKind::U16 |
/// MetadataValueKind::U32 |
/// MetadataValueKind::U64 => println!("{} is an integer", key_name),
/// MetadataValueKind::F64 => println!("{} is a float", key_name),
/// MetadataValueKind::Bool => println!("{} is a boolean", key_name),
/// MetadataValueKind::Array => println!("{} is an array", key_name),
/// MetadataValueKind::Map => println!("{} is a map", key_name),
/// MetadataValueKind::Unsupported => println!("{} is not a supported type", key_name),
/// }
/// } else {
/// println!("Metadata does not have a {} key", key_name);
/// }
/// ```
pub fn kind(&self) -> ValueKind {
ValueKind::from(self)
}
/// Returns the value as a `Some(Vec<&str>)` if it is a `MetadataValue::Array`. Any elements
/// that are not `MetadataValue::String` values will be ignored.
pub fn as_str_array(&self) -> Option<Vec<&str>> {
match *self {
Value::Array(ref vec) => Some(vec.iter().flat_map(Value::as_str).collect()),
Value::String(ref string) => Some(vec![string.as_ref()]),
_ => None,
}
}
/// Returns the value as a `Some(u8)` if it is a `MetadataValue::U8`, or `None` otherwise.
pub fn as_u8(&self) -> Option<u8> {
match *self {
Value::U8(val) => Some(val),
_ => None,
}
}
/// Returns the value as a `Some(u16)` if it is an unsigned int smaller than or equal to u16,
/// or `None` otherwise.
pub fn as_u16(&self) -> Option<u16> {
match *self {
Value::U16(val) => Some(val),
Value::U8(val) => Some(u16::from(val)),
_ => None,
}
}
/// Returns the value as a `Some(u32)` if it is an unsigned int smaller than or equal to u32,
/// or `None` otherwise.
pub fn as_u32(&self) -> Option<u32> {
match *self {
Value::U32(val) => Some(val),
Value::U16(val) => Some(u32::from(val)),
Value::U8(val) => Some(u32::from(val)),
_ => None,
}
}
/// Returns the value as a `Some(u64)` if it is an unsigned int smaller than or equal to u64,
/// or `None` otherwise.
pub fn as_u64(&self) -> Option<u64> {
match *self {
Value::U64(val) => Some(val),
Value::U32(val) => Some(u64::from(val)),
Value::U16(val) => Some(u64::from(val)),
Value::U8(val) => Some(u64::from(val)),
_ => None,
}
}
/// Returns the value as a `Some(i16)` if it is a signed integer smaller than or equal to i16,
/// or `None` otherwise.
pub fn as_i16(&self) -> Option<i16> {
match *self {
Value::I16(val) => Some(val),
_ => None,
}
}
/// Returns the value as a `Some(i32)` if it is a signed integer smaller than or equal to i32,
/// or `None` otherwise.
pub fn as_i32(&self) -> Option<i32> {
match *self {
Value::I32(val) => Some(val),
Value::I16(val) => Some(i32::from(val)),
_ => None,
}
}
/// Returns the value as a `Some(i64)` if it is a signed integer smaller than or equal to i64,
/// or `None` otherwise.
pub fn as_i64(&self) -> Option<i64> {
match *self {
Value::I64(val) => Some(val),
Value::I32(val) => Some(i64::from(val)),
Value::I16(val) => Some(i64::from(val)),
_ => None,
}
}
/// Returns the value as a `Some(f64)` if it is a `MetadataValue::F64`, or `None` otherwise.
pub fn as_f64(&self) -> Option<f64> {
match *self {
Value::F64(val) => Some(val),
_ => None,
}
}
/// Returns the value as a `Some(bool)` if it is a `MetadataValue::Bool`, or `None` otherwise.
pub fn as_bool(&self) -> Option<bool> {
match *self {
Value::Bool(val) => Some(val),
_ => None,
}
}
/// Returns the value as a `Some(&str)` if it is a `MetadataValue::String`, or `None` otherwise.
pub fn as_str(&self) -> Option<&str> {
match *self {
Value::String(ref val) => Some(val),
_ => None,
}
}
/// Returns the value as a `Some(&String)` if it is a `MetadataValue::String`, or `None` otherwise.
pub fn as_string(&self) -> Option<&String> {
match *self {
Value::String(ref val) => Some(val),
_ => None,
}
}
/// Returns the value as a `Some(&HashMap<String, Value>)` if it is a `MetadataValue::Map`, or `None` otherwise.
pub fn as_map(&self) -> Option<&HashMap<String, Value>> {
match *self {
Value::Map(ref val) => Some(val),
_ => None,
}
}
/// Returns the value as a `Some(&Vec<Value>)` if it is a `MetadataValue::Array`, or `None` otherwise.
pub fn as_array(&self) -> Option<&Vec<Value>> {
match *self {
Value::Array(ref val) => Some(val),
_ => None,
}
}
/// Consumes `self` and returns the inner value as a `Some(u8)` if it is a `MetadataValue::U8`, or `None` otherwise.
pub fn into_u8(self) -> Option<u8> {
match self {
Value::U8(val) => Some(val),
_ => None,
}
}
/// Consumes `self` and returns the inner value as a `Some(u16)` if it is an unsigned integer
/// smaller than or equal to u16, or `None` otherwise.
pub fn into_u16(self) -> Option<u16> {
match self {
Value::U16(val) => Some(val),
Value::U8(val) => Some(u16::from(val)),
_ => None,
}
}
/// Consumes `self` and returns the inner value as a `Some(u32)` if it is an unsigned integer
/// smaller than or equal to u32, or `None` otherwise.
pub fn into_u32(self) -> Option<u32> {
match self {
Value::U32(val) => Some(val),
Value::U16(val) => Some(u32::from(val)),
Value::U8(val) => Some(u32::from(val)),
_ => None,
}
}
/// Consumes `self` and returns the inner value as a `Some(u64)` if it is an unsigned integer
/// smaller than or equal to u64, or `None` otherwise.
pub fn into_u64(self) -> Option<u64> {
match self {
Value::U64(val) => Some(val),
Value::U32(val) => Some(u64::from(val)),
Value::U16(val) => Some(u64::from(val)),
Value::U8(val) => Some(u64::from(val)),
_ => None,
}
}
/// Consumes `self` and returns the inner value as a `Some(i16)` if it is a signed integer
/// smaller than or equal to i16, or `None` otherwise.
pub fn into_i16(self) -> Option<i16> {
match self {
Value::I16(val) => Some(val),
_ => None,
}
}
/// Consumes `self` and returns the inner value as a `Some(i32)` if it is a signed integer
/// smaller than or equal to i32, or `None` otherwise.
pub fn into_i32(self) -> Option<i32> {
match self {
Value::I32(val) => Some(val),
Value::I16(val) => Some(i32::from(val)),
_ => None,
}
}
/// Consumes `self` and returns the inner value as a `Some(i64)` if it is a signed integer
/// smaller than or equal to i64, or `None` otherwise.
pub fn into_i64(self) -> Option<i64> {
match self {
Value::I64(val) => Some(val),
Value::I32(val) => Some(i64::from(val)),
Value::I16(val) => Some(i64::from(val)),
_ => None,
}
}
/// Consumes `self` and returns the inner value as a `Some(f64)` if it is a
/// `MetadataValue::F64`, or `None` otherwise.
pub fn into_f64(self) -> Option<f64> {
match self {
Value::F64(val) => Some(val),
_ => None,
}
}
/// Consumes `self` and returns the inner value as a `Some(bool)` if it is a
/// `MetadataValue::Bool`, or `None` otherwise.
pub fn into_bool(self) -> Option<bool> {
match self {
Value::Bool(val) => Some(val),
_ => None,
}
}
/// Consumes `self` and returns the inner value as a `Some(String)` if it is a
/// `MetadataValue::String`, or `None` otherwise.
pub fn into_string(self) -> Option<String> {
match self {
Value::String(val) => Some(val),
_ => None,
}
}
/// Consumes `self` and returns the inner value as a `Some(HashMap<String, Value>)` if it is a
/// `MetadataValue::Map`, or `None` otherwise.
pub fn into_map(self) -> Option<HashMap<String, Value>> {
match self {
Value::Map(val) => Some(val),
_ => None,
}
}
/// Consumes `self` and returns the inner value as a `Some(Vec<Value>)` if it is a
/// `MetadataValue::Array`, or `None` otherwise.
pub fn into_array(self) -> Option<Vec<Value>> {
match self {
Value::Array(val) => Some(val),
_ => None,
}
}
}
impl<'a> From<&'a str> for Value {
fn from(string: &'a str) -> Value {
Value::String(String::from(string))
}
}
impl dbus::arg::Arg for Value {
const ARG_TYPE: ArgType = ArgType::Variant;
fn signature() -> dbus::Signature<'static> {
dbus::Signature::from_slice("v").unwrap()
}
}
impl<'a> dbus::arg::Get<'a> for Value {
fn get(i: &mut dbus::arg::Iter<'_>) -> Option<Self> {
let arg_type = i.arg_type();
// Trying to calculate signature of an invalid arg will panic, so abort early.
if let ArgType::Invalid = arg_type {
return None;
}
let signature = i.signature();
match arg_type {
// Hashes in DBus are arrays of Dict pairs ({string, variant})
ArgType::Array if *signature == *"a{sv}" => {
i.get::<HashMap<String, Value>>().map(Value::Map)
}
ArgType::Array => i.get::<Vec<Value>>().map(Value::Array),
ArgType::Boolean => i.get::<bool>().map(Value::Bool),
ArgType::Byte => i.get::<u8>().map(Value::U8),
ArgType::Double => i.get::<f64>().map(Value::F64),
ArgType::Int16 => i.get::<i16>().map(Value::I16),
ArgType::Int32 => i.get::<i32>().map(Value::I32),
ArgType::Int64 => i.get::<i64>().map(Value::I64),
ArgType::String => i.get::<String>().map(Value::String),
ArgType::UInt16 => i.get::<u16>().map(Value::U16),
ArgType::UInt32 => i.get::<u32>().map(Value::U32),
ArgType::UInt64 => i.get::<u64>().map(Value::U64),
ArgType::Variant => i.recurse(ArgType::Variant).and_then(|mut iter| iter.get()),
ArgType::Invalid => unreachable!("Early return at the top of the method"),
ArgType::ObjectPath => i
.get::<dbus::Path<'_>>()
.map(|p| Value::String(p.to_string())),
ArgType::DictEntry | ArgType::UnixFd | ArgType::Signature | ArgType::Struct => {
Some(Value::Unsupported)
}
}
}
}
#[cfg(test)]
mod tests {
use super::*;
use dbus::arg::{Append, RefArg, Variant};
use dbus::ffidisp::{BusType, Connection, ConnectionItem};
use dbus::Message;
fn send_values_over_dbus<F>(appender: F) -> Message
where
F: FnOnce(Message) -> Message,
{
//
// Open a connection, send a message to it and then read the message back again.
//
let connection = Connection::get_private(BusType::Session)
.expect("Could not open a D-Bus session connection");
connection
.register_object_path("/hello")
.expect("Could not register object path");
let send_message = Message::new_method_call(
&connection.unique_name(),
"/hello",
"com.example.hello",
"Hello",
)
.expect("Could not create message");
let send_message = appender(send_message);
connection
.send(send_message)
.expect("Could not send message to myself");
for item in connection.iter(200) {
if let ConnectionItem::MethodCall(received_message) = item {
return received_message;
}
}
panic!("Did not find a message on the bus");
}
fn send_value_over_dbus<T: Append>(value: T) -> Message {
send_values_over_dbus(|message| message.append1(value))
}
#[test]
fn it_supports_strings() {
let message = send_value_over_dbus("Hello world!");
let string: Value = message.get1().unwrap();
assert!(string.is_string());
assert_eq!(string.as_str(), Some("Hello world!"));
}
#[test]
fn it_supports_object_paths_as_strings() {
let message = send_value_over_dbus(dbus::Path::from("/hello/world"));
let string: Value = message.get1().unwrap();
assert!(string.is_string());
assert_eq!(string.as_str(), Some("/hello/world"));
}
#[test]
fn it_supports_unsigned_integers() {
let message = send_values_over_dbus(|input| input.append3(1u8, 2u16, 3u32).append1(4u64));
let mut values = message.iter_init();
let eight: Value = values.read().unwrap();
let sixteen: Value = values.read().unwrap();
let thirtytwo: Value = values.read().unwrap();
let sixtyfour: Value = values.read().unwrap();
assert_eq!(Value::U8(1), eight);
assert_eq!(Value::U16(2), sixteen);
assert_eq!(Value::U32(3), thirtytwo);
assert_eq!(Value::U64(4), sixtyfour);
}
#[test]
fn it_supports_signed_integers() {
let message = send_values_over_dbus(|input| input.append3(1i16, 2i32, 3i64));
let mut values = message.iter_init();
let sixteen: Value = values.read().unwrap();
let thirtytwo: Value = values.read().unwrap();
let sixtyfour: Value = values.read().unwrap();
assert_eq!(Value::I16(1), sixteen);
assert_eq!(Value::I32(2), thirtytwo);
assert_eq!(Value::I64(3), sixtyfour);
}
#[test]
fn it_supports_floats() {
let message = send_value_over_dbus(42.0f64);
let float: Value = message.get1().unwrap();
assert!(float.is_f64());
assert_eq!(float.as_f64(), Some(42.0));
}
#[test]
fn it_supports_booleans() {
let message = send_value_over_dbus(true);
let boolean: Value = message.get1().unwrap();
assert!(boolean.is_bool());
assert_eq!(boolean.as_bool(), Some(true));
}
#[test]
fn it_supports_arrays_of_variants() {
let input: Vec<Variant<Box<dyn RefArg>>> = vec![
Variant(Box::new(String::from("World"))),
Variant(Box::new(42u8)),
];
let expected = vec![Value::String("World".into()), Value::U8(42)];
let message = send_value_over_dbus(input);
let array: Value = message.get1().unwrap();
assert!(array.is_array());
assert_eq!(array.into_array(), Some(expected));
}
#[test]
fn it_supports_arrays_of_strings() {
let input: Vec<String> = vec!["Hello".into(), "World".into()];
let expected: Vec<Value> = vec!["Hello".into(), "World".into()];
let message = send_value_over_dbus(input);
let array: Value = message.get1().unwrap();
assert!(array.is_array());
assert_eq!(array.into_array(), Some(expected));
}
#[test]
fn it_supports_maps_of_variants() {
let mut input: HashMap<String, Variant<Box<dyn RefArg>>> = HashMap::new();
input.insert(
String::from("receiver"),
Variant(Box::new(String::from("World"))),
);
input.insert(String::from("times"), Variant(Box::new(42u8)));
let mut expected = HashMap::new();
expected.insert(
String::from("receiver"),
Value::String(String::from("World")),
);
expected.insert(String::from("times"), Value::U8(42));
let message = send_value_over_dbus(input);
let hash: Value = message.get1().unwrap();
assert!(hash.is_map());
assert_eq!(hash.into_map(), Some(expected));
}
}