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//! This crate provides a client to the watchman file watching service. //! //! Start with the [Connector](struct.Connector.html) struct and use //! it to connect and return a [Client](struct.Client.html) struct, //! [Client::resolve_root](struct.Client.html#method.resolve_root) to //! resolve a path and initiate a watch, and then //! [Client::query](struct.Client.html#method.query) to perform //! a query, or [Client::subscribe](struct.Client.html#method.subscribe) //! to subscribe to file changes in real time. //! //! This example shows how to connect and expand a glob from the //! current working directory: //! //! ```norun //! use watchman_client::prelude::*; //! #[tokio::main] //! async fn main() -> Result<(), Box<dyn std::error::Error>> { //! let mut client = Connector::new().connect().await?; //! let resolved = client //! .resolve_root(CanonicalPath::canonicalize(".")?) //! .await?; //! //! // Basic globs -> names //! let files = client.glob(&resolved, &["**/*.rs"]).await?; //! println!("files: {:#?}", files); //! Ok(()) //! } //! ``` pub mod expr; pub mod fields; mod named_pipe; pub mod pdu; use serde_bser::de::{Bunser, PduInfo, SliceRead}; use serde_bser::value::Value; use std::collections::{HashMap, VecDeque}; use std::marker::PhantomData; use std::path::{Path, PathBuf}; use std::sync::atomic::{AtomicUsize, Ordering}; use std::sync::Arc; use thiserror::Error; use tokio::io::{AsyncRead, AsyncReadExt, AsyncWrite, AsyncWriteExt}; #[cfg(unix)] use tokio::net::UnixStream; use tokio::process::Command; use tokio::sync::mpsc::{Receiver, Sender, UnboundedReceiver, UnboundedSender}; use tokio::sync::Mutex; /// The next id number to use when generating a subscription name static SUB_ID: AtomicUsize = AtomicUsize::new(1); /// `use watchman_client::prelude::*` for convenient access to the types /// provided by this crate pub mod prelude { pub use crate::expr::*; pub use crate::fields::*; pub use crate::pdu::*; pub use crate::query_result_type; pub use crate::{CanonicalPath, Client, Connector, ResolvedRoot}; } use prelude::*; #[derive(Error, Debug)] pub enum Error { #[error("IO Error: {0}")] Tokio(#[from] tokio::io::Error), #[error( "While invoking the {watchman_path} CLI to discover the server connection details: {reason}, stderr=`{stderr}`" )] ConnectionDiscovery { watchman_path: PathBuf, reason: String, stderr: String, }, #[error("The watchman server reported an error: \"{}\", while executing command: {}", .message, .command)] WatchmanServerError { message: String, command: String }, #[error("The watchman server reported an error: \"{}\"", .message)] WatchmanResponseError { message: String }, #[error("The watchman server didn't return a value for field `{}` in response to a `{}` command. {:?}", .fieldname, .command, .response)] MissingField { fieldname: &'static str, command: String, response: String, }, #[error("Unexpected EOF from server")] Eof, #[error("{source} (data: {data:x?})")] Deserialize { source: Box<dyn std::error::Error + Send>, data: Vec<u8>, }, #[error("{source}")] Serialize { source: Box<dyn std::error::Error + Send>, }, #[error("while attempting to connect to {endpoint}: {source}")] Connect { endpoint: PathBuf, source: Box<dyn std::error::Error + Send>, }, #[error("{0}")] Generic(String), } impl Error { fn generic<T: std::fmt::Display>(error: T) -> Self { Self::Generic(format!("{}", error)) } } /// The Connector defines how to connect to the watchman server. /// You will typically use `Connector::new` to set up the connection with /// the environmental defaults. You might want to override those defaults /// in situations such as integration testing environments, or in extremely /// latency sensitive environments where the cost of performing discovery /// is a measurable overhead. #[derive(Default)] pub struct Connector { watchman_cli_path: Option<PathBuf>, unix_domain: Option<PathBuf>, } impl Connector { /// Set up the connector with the system defaults. /// If `WATCHMAN_SOCK` is set in the environment it will preset the /// local IPC socket path. /// Otherwise the connector will invoke the watchman CLI to perform /// discovery. pub fn new() -> Self { let connector = Self::default(); if let Some(val) = std::env::var_os("WATCHMAN_SOCK") { connector.unix_domain_socket(val) } else { connector } } /// If the watchman CLI is installed in a location that is not present /// in the PATH environment variable, this method is used to inform /// the connector of its location. pub fn watchman_cli_path<P: AsRef<Path>>(mut self, path: P) -> Self { self.watchman_cli_path = Some(path.as_ref().to_path_buf()); self } /// Specify the unix domain socket path pub fn unix_domain_socket<P: AsRef<Path>>(mut self, path: P) -> Self { self.unix_domain = Some(path.as_ref().to_path_buf()); self } /// Resolve the unix domain socket path, taking either the override /// or performing discovery. async fn resolve_unix_domain_path(&self) -> Result<PathBuf, Error> { if let Some(path) = self.unix_domain.as_ref() { Ok(path.clone()) } else { let watchman_path = self .watchman_cli_path .as_ref() .map(|p| p.as_ref()) .unwrap_or_else(|| Path::new("watchman")); let output = Command::new(watchman_path) .args(&["--output-encoding", "bser-v2", "get-sockname"]) .output() .await .map_err(|source| Error::ConnectionDiscovery { watchman_path: watchman_path.to_path_buf(), reason: source.to_string(), stderr: "".to_string(), })?; let info: GetSockNameResponse = serde_bser::from_slice(&output.stdout).map_err(|source| { Error::ConnectionDiscovery { watchman_path: watchman_path.to_path_buf(), reason: source.to_string(), stderr: String::from_utf8_lossy(&output.stderr).into_owned(), } })?; let debug = format!("{:#?}", info); if let Some(message) = info.error { return Err(Error::WatchmanServerError { message, command: "get-sockname".into(), }); } info.sockname.ok_or_else(|| Error::MissingField { fieldname: "sockname", command: "get-sockname".into(), response: debug, }) } } /// Establish a connection to the watchman server. /// If the connector was configured to perform discovery (which is /// the default configuration), then this will attempt to start /// the watchman server. pub async fn connect(self) -> Result<Client, Error> { let sock_path = self.resolve_unix_domain_path().await?; #[cfg(unix)] let stream: Box<dyn ReadWriteStream> = Box::new(UnixStream::connect(sock_path).await?); #[cfg(windows)] let stream: Box<dyn ReadWriteStream> = Box::new(named_pipe::NamedPipe::connect(sock_path).await?); let (reader, writer) = tokio::io::split(stream); let (request_tx, request_rx) = tokio::sync::mpsc::channel(128); let mut reader_task = ReaderTask { reader, request_tx: request_tx.clone(), }; tokio::spawn(async move { if let Err(err) = reader_task.run().await { eprintln!("watchman reader task failed: {}", err); } }); let mut task = ClientTask { writer, request_rx, request_queue: VecDeque::new(), waiting_response: false, subscriptions: HashMap::new(), }; tokio::spawn(async move { if let Err(err) = task.run().await { eprintln!("watchman client task failed: {}", err); } }); let inner = Arc::new(Mutex::new(ClientInner { request_tx })); Ok(Client { inner }) } } /// Represents a canonical path in the filesystem. #[derive(Debug)] pub struct CanonicalPath(PathBuf); impl CanonicalPath { /// Construct the canonical version of the supplied path. /// This function will canonicalize the path and return the /// result, if successful. /// If you have already canonicalized the path, it is preferable /// to use the `with_canonicalized_path` function instead. pub fn canonicalize<P: AsRef<Path>>(path: P) -> Result<Self, std::io::Error> { let path = std::fs::canonicalize(path)?; Ok(Self(Self::strip_unc_escape(path))) } /// Construct from an already canonicalized path. /// This function will panic if the supplied path is not an absolute /// path! pub fn with_canonicalized_path(path: PathBuf) -> Self { assert!( path.is_absolute(), "attempted to call \ CanonicalPath::with_canonicalized_path on a non-canonical path! \ You probably want to call CanonicalPath::canonicalize instead!" ); Self(Self::strip_unc_escape(path)) } /// Watchman doesn't like the UNC prefix being present for incoming paths /// in its current implementation: we should fix that, but in the meantime /// we want clients to be able to connect to existing versions, so let's /// strip off the UNC escape #[cfg(windows)] #[inline] fn strip_unc_escape(path: PathBuf) -> PathBuf { match path.to_str() { Some(s) if s.starts_with("\\\\?\\") => PathBuf::from(&s[4..]), _ => path, } } #[cfg(unix)] #[inline] fn strip_unc_escape(path: PathBuf) -> PathBuf { path } } /// Data that describes a watched filesystem location. /// Watchman performs watch aggregation to project boundaries, so a request /// to watch a subdirectory will resolve to the higher level root path /// and a relative path offset. /// This struct encodes both pieces of information. #[derive(Debug, Clone)] pub struct ResolvedRoot { root: PathBuf, relative: Option<PathBuf>, watcher: String, } impl ResolvedRoot { /// Returns the name of the watcher that the server is using to /// monitor the path. The watcher is generally system dependent, /// but some systems offer multipler watchers. /// You generally don't care too much about the watcher that is /// in use, but if the watcher is a virtualized filesystem such as /// `eden` then you may wish to use to alternative queries to get the /// best performance. pub fn watcher(&self) -> &str { self.watcher.as_str() } /// Returns the root of the watchman project that is being watched pub fn project_root(&self) -> &Path { &self.root } /// Returns the absolute path to the directory that you requested be resolved. pub fn path(&self) -> PathBuf { if let Some(relative) = self.relative.as_ref() { self.root.join(relative) } else { self.root.clone() } } /// Returns the path to the directory that you requested be resolved, /// relative to the `project_root`. pub fn project_relative_path(&self) -> Option<&Path> { self.relative.as_ref().map(PathBuf::as_ref) } } trait ReadWriteStream: AsyncRead + AsyncWrite + std::marker::Unpin + Send {} #[cfg(unix)] impl ReadWriteStream for UnixStream {} struct SendRequest { /// The serialized request to send to the server buf: Vec<u8>, /// to pass the response back to the requstor tx: tokio::sync::oneshot::Sender<Result<Vec<u8>, String>>, } impl SendRequest { fn respond(self, result: Result<Vec<u8>, String>) -> Result<(), Error> { self.tx .send(result) .map_err(|_| Error::generic("requestor has dropped its receiver")) } } enum TaskItem { QueueRequest(SendRequest), ProcessReceivedPdu(Vec<u8>), RegisterSubscription(String, UnboundedSender<Vec<u8>>), } /// A live connection to a watchman server. /// Use [Connector](struct.Connector.html) to establish a connection. pub struct Client { inner: Arc<Mutex<ClientInner>>, } /// The reader task lives to read a PDU and send it to the ClientTask struct ReaderTask { reader: tokio::io::ReadHalf<Box<dyn ReadWriteStream>>, request_tx: Sender<TaskItem>, } impl ReaderTask { async fn run(&mut self) -> Result<(), Error> { loop { let pdu = self.read_pdu_vec().await?; self.request_tx .send(TaskItem::ProcessReceivedPdu(pdu)) .await .map_err(Error::generic)?; } } /// Sniffs out the BSER PDU header to determine the length of data that /// needs to be read in order to decode the full PDU async fn read_bser_pdu_length(&mut self) -> Result<PduHeader, Error> { // We know that the smallest full PDU returned by the server // won't ever be smaller than this size const BUF_SIZE: usize = 16; let mut buf = [0u8; BUF_SIZE]; let pos = self.reader.read(&mut buf).await?; if pos == 0 { return Err(Error::Eof); } let buf = &buf[..pos]; let mut bunser = Bunser::new(SliceRead::new(buf)); let pdu = bunser.read_pdu().map_err(|source| Error::Deserialize { source: Box::new(source), data: buf.to_vec(), })?; let buf = buf.to_vec(); Ok(PduHeader { buf, pdu }) } /// Read the bytes that comprise a BSER encoded PDU async fn read_pdu_vec(&mut self) -> Result<Vec<u8>, Error> { let header = self.read_bser_pdu_length().await?; let total_size = (header.pdu.start + header.pdu.len) as usize; let mut buf = header.buf; let mut end = buf.len(); buf.resize(total_size, 0); while end != total_size { let n = self .reader .read(&mut buf.as_mut_slice()[end..total_size]) .await?; if n == 0 { return Err(Error::Eof); } end += n; } Ok(buf) } } /// The client task coordinates sending requests with processing /// unilateral results struct ClientTask { writer: tokio::io::WriteHalf<Box<dyn ReadWriteStream>>, request_rx: Receiver<TaskItem>, request_queue: VecDeque<SendRequest>, waiting_response: bool, subscriptions: HashMap<String, UnboundedSender<Vec<u8>>>, } impl Drop for ClientTask { fn drop(&mut self) { self.fail_all(&Error::generic("the client task terminated")); } } impl ClientTask { async fn run(&mut self) -> Result<(), Error> { // process things, and if we encounter an error, ensure that // we fail all outstanding requests match self.run_loop().await { Err(err) => { self.fail_all(&err); Err(err) } ok => ok, } } async fn run_loop(&mut self) -> Result<(), Error> { loop { match self.request_rx.recv().await { Some(TaskItem::QueueRequest(request)) => self.queue_request(request).await?, Some(TaskItem::ProcessReceivedPdu(pdu)) => self.process_pdu(pdu).await?, Some(TaskItem::RegisterSubscription(name, tx)) => { self.register_subscription(name, tx) } None => break, }; } Ok(()) } fn register_subscription(&mut self, name: String, tx: UnboundedSender<Vec<u8>>) { self.subscriptions.insert(name, tx); } /// Generate an error for each queued request. /// This is called in situations where the state of the connection /// to the serve is non-recoverable. fn fail_all(&mut self, err: &Error) { while let Some(request) = self.request_queue.pop_front() { request.respond(Err(err.to_string())).ok(); } } /// If we're not waiting for the response to a request, /// then send the next one! async fn send_next_request(&mut self) -> Result<(), Error> { if !self.waiting_response && !self.request_queue.is_empty() { match self .writer .write_all(&self.request_queue.front().expect("not empty").buf) .await { Err(err) => { // A failed write breaks our world; we don't want to // try to continue return Err(err.into()); } Ok(_) => self.waiting_response = true, } } Ok(()) } /// Queue up a new request from the client code, and then /// check to see if we can send a queued request to the server. async fn queue_request(&mut self, request: SendRequest) -> Result<(), Error> { self.request_queue.push_back(request); self.send_next_request().await?; Ok(()) } /// Dispatch a PDU that we just read to the appropriate client code. async fn process_pdu(&mut self, pdu: Vec<u8>) -> Result<(), Error> { use serde::Deserialize; #[derive(Deserialize, Debug)] pub struct Unilateral { pub unilateral: bool, pub subscription: String, } if let Ok(unilateral) = bunser::<Unilateral>(&pdu) { if let Some(subscription) = self.subscriptions.get_mut(&unilateral.subscription) { if subscription.send(pdu).is_err() { // The `Subscription` was dropped; we don't need to // treat this as terminal for this client session, // so just de-register the handler self.subscriptions.remove(&unilateral.subscription); } } } else if self.waiting_response { let request = self .request_queue .pop_front() .expect("waiting_response is only true when request_queue is not empty"); self.waiting_response = false; request.respond(Ok(pdu))?; } else { // This should never happen as we're not doing any subscription stuff return Err(Error::generic("received a unilateral PDU from the server")); } self.send_next_request().await?; Ok(()) } } struct PduHeader { buf: Vec<u8>, pdu: PduInfo, } fn bunser<T>(buf: &[u8]) -> Result<T, Error> where T: serde::de::DeserializeOwned, { let response: T = serde_bser::from_slice(&buf).map_err(|source| Error::Deserialize { source: Box::new(source), data: buf.to_vec(), })?; Ok(response) } struct ClientInner { request_tx: Sender<TaskItem>, } impl ClientInner { /// This method will send a request to the watchman server /// and wait for its response. /// This is really an internal method, but it is made public in case a /// consumer of this crate needs to issue a command for which we haven't /// yet made an ergonomic wrapper. pub(crate) async fn generic_request<Request, Response>( &mut self, request: Request, ) -> Result<Response, Error> where Request: serde::Serialize + std::fmt::Debug, Response: serde::de::DeserializeOwned, { // Step 1: serialize into a bser byte buffer let mut request_data = vec![]; serde_bser::ser::serialize(&mut request_data, &request).map_err(|source| { Error::Serialize { source: Box::new(source), } })?; // Step 2: ask the client task to send it for us let (tx, rx) = tokio::sync::oneshot::channel(); self.request_tx .send(TaskItem::QueueRequest(SendRequest { buf: request_data, tx, })) .await .map_err(Error::generic)?; // Step 3: wait for the client task to give us the response let pdu_data = rx.await.map_err(Error::generic)?.map_err(Error::generic)?; // Step 4: sniff for an error response in the deserialized data use serde::Deserialize; #[derive(Deserialize, Debug)] struct MaybeError { #[serde(default)] error: Option<String>, } // Step 5: deserialize into the caller-desired format let maybe_err: MaybeError = bunser(&pdu_data)?; if let Some(message) = maybe_err.error { return Err(Error::WatchmanServerError { message, command: format!("{:#?}", request), }); } let response: Response = bunser(&pdu_data)?; Ok(response) } } /// Returned by [Subscription::next](struct.Subscription.html#method.next) /// as events are observed by Watchman. #[allow(clippy::large_enum_variant)] #[derive(Debug, Clone)] pub enum SubscriptionData<F> where F: serde::de::DeserializeOwned + std::fmt::Debug + Clone + QueryFieldList, { /// The Subscription was canceled. /// This could be for a number of reasons that are not knowable /// to the client: /// * The user may have issued the `watch-del` command /// * The containing watch root may have been deleted or /// un-mounted /// * The containing watch may no longer be accessible /// to the watchman user/process /// * Some other error condition that renders the project /// unwatchable may have occurred /// * The server may have been gracefully shutdown /// /// A Canceled subscription will deliver no further results. Canceled, /// Files matching your criteria have changed. /// The QueryResult contains the details. /// Pay attention to the /// [is_fresh_instance](pdu/struct.QueryResult.html#structfield.is_fresh_instance) field! FilesChanged(QueryResult<F>), /// Some other watchman client has broadcast that the watched /// project is entering a new named state. /// For example, `hg.update` may be generated by the FB /// internal source control system to indicate that the /// working copy is about to be updated to a new revision. /// The metadata field contains data specific to the named /// state. StateEnter { state_name: String, metadata: Option<Value>, }, /// Some other watchman client has broadcast that the watched /// project is no longer in the named state. /// This event can also be generated if the watchman client /// that entered the state disconnects unexpectedly from /// the watchman server. /// The `metadata` field will be `None` in that situation. StateLeave { state_name: String, metadata: Option<Value>, }, } /// A handle to a subscription initiated via `Client::subscribe`. /// Repeatedly call `Subscription::next().await` to yield the next /// set of subscription results. /// Use the `cancel` method to gracefully halt this subscription /// if you have a program that creates and destroys subscriptions /// throughout its lifetime. pub struct Subscription<F> where F: serde::de::DeserializeOwned + std::fmt::Debug + Clone + QueryFieldList, { name: String, inner: Arc<Mutex<ClientInner>>, root: ResolvedRoot, responses: UnboundedReceiver<Vec<u8>>, _phantom: PhantomData<F>, } impl<F> Subscription<F> where F: serde::de::DeserializeOwned + std::fmt::Debug + Clone + QueryFieldList, { /// Returns the assigned name for this subscription instance. pub fn name(&self) -> &str { &self.name } /// Yield the next set of subscription data. /// An error is generated if the subscription is disconnected /// from the server. #[allow(clippy::should_implement_trait)] pub async fn next(&mut self) -> Result<SubscriptionData<F>, Error> { let pdu = self .responses .recv() .await .ok_or_else(|| Error::generic("client was torn down"))?; let response: QueryResult<F> = bunser(&pdu)?; if response.subscription_canceled { self.responses.close(); Ok(SubscriptionData::Canceled) } else if let Some(state_name) = response.state_enter { Ok(SubscriptionData::StateEnter { state_name, metadata: response.state_metadata, }) } else if let Some(state_name) = response.state_leave { Ok(SubscriptionData::StateLeave { state_name, metadata: response.state_metadata, }) } else { Ok(SubscriptionData::FilesChanged(response)) } } /// Gracefully cancel this subscription. /// If you are imminently about to drop the associated client then you /// need not call this method. /// However, if the associated client is going to live much longer /// than a Subscription that you are about to drop, /// then it is recommended that you call `cancel` so that the server /// will stop delivering data about it. pub async fn cancel(self) -> Result<(), Error> { let mut inner = self.inner.lock().await; let _: UnsubscribeResponse = inner .generic_request(Unsubscribe("unsubscribe", self.root.root, self.name)) .await?; Ok(()) } } impl Client { /// This method will send a request to the watchman server /// and wait for its response. /// This is really an internal method, but it is made public in case a /// consumer of this crate needs to issue a command for which we haven't /// yet made an ergonomic wrapper. #[doc(hidden)] pub async fn generic_request<Request, Response>( &self, request: Request, ) -> Result<Response, Error> where Request: serde::Serialize + std::fmt::Debug, Response: serde::de::DeserializeOwned, { let mut inner = self.inner.lock().await; let response: Response = inner.generic_request(request).await?; Ok(response) } /// This is typically the first method invoked on a client. /// Its purpose is to ensure that the watchman server is watching the specified /// path and to resolve it to a `ResolvedRoot` instance. /// /// The path to resolve must be a canonical path; watchman performs strict name /// resolution to detect TOCTOU issues and will generate an error if the path /// is not the canonical name. /// /// Note that for regular filesystem watches, if the requested path is not /// yet being watched, this method will not yield until the watchman server /// has completed a recursive crawl of that portion of the filesystem. /// In other words, the worst case performance of this is /// `O(recursive-number-of-files)` and is impacted by the underlying storage /// device and its performance characteristics. pub async fn resolve_root(&self, path: CanonicalPath) -> Result<ResolvedRoot, Error> { let response: WatchProjectResponse = self .generic_request(WatchProjectRequest("watch-project", path.0.clone())) .await?; Ok(ResolvedRoot { root: response.watch, relative: response.relative_path, watcher: response.watcher, }) } /// Perform a generic watchman query. /// The `F` type is a struct defined by the /// [query_result_type!](macro.query_result_type.html) macro, /// or, if you want only the file name from the results, the /// [NameOnly](struct.NameOnly.html) struct. /// /// ``` /// use watchman_client::prelude::*; /// use serde::Deserialize; /// /// query_result_type! { /// struct NameAndType { /// name: NameField, /// file_type: FileTypeField, /// } /// } /// /// async fn query( /// client: &mut Client, /// resolved: &ResolvedRoot /// ) -> Result<(), Box<dyn std::error::Error>> { /// let response: QueryResult<NameAndType> = client /// .query( /// &resolved, /// QueryRequestCommon { /// glob: Some(vec!["**/*.rs".to_string()]), /// ..Default::default() /// }, /// ) /// .await?; /// println!("response: {:#?}", response); /// Ok(()) /// } /// ``` /// /// When constructing your result type, you can select from the /// following fields: /// /// * [CTimeAsFloatField](struct.CTimeAsFloatField.html) /// * [CTimeField](struct.CTimeField.html) /// * [ContentSha1HexField](struct.ContentSha1HexField.html) /// * [CreatedClockField](struct.CreatedClockField.html) /// * [DeviceNumberField](struct.DeviceNumberField.html) /// * [ExistsField](struct.ExistsField.html) /// * [FileTypeField](struct.FileTypeField.html) /// * [InodeNumberField](struct.InodeNumberField.html) /// * [MTimeAsFloatField](struct.MTimeAsFloatField.html) /// * [MTimeField](struct.MTimeField.html) /// * [ModeAndPermissionsField](struct.ModeAndPermissionsField.html) /// * [NameField](struct.NameField.html) /// * [NewField](struct.NewField.html) /// * [NumberOfLinksField](struct.NumberOfLinksField.html) /// * [ObservedClockField](struct.ObservedClockField.html) /// * [OwnerGidField](struct.OwnerGidField.html) /// * [OwnerUidField](struct.OwnerUidField.html) /// * [SizeField](struct.SizeField.html) /// * [SymlinkTargetField](struct.SymlinkTargetField.html) /// /// (See [the fields module](fields/index.html) for a definitive list) /// /// The file names are all relative to the `root` parameter. pub async fn query<F>( &self, root: &ResolvedRoot, query: QueryRequestCommon, ) -> Result<QueryResult<F>, Error> where F: serde::de::DeserializeOwned + std::fmt::Debug + Clone + QueryFieldList, { let query = QueryRequest( "query", root.root.clone(), QueryRequestCommon { relative_root: root.relative.clone(), fields: F::field_list(), ..query }, ); let response: QueryResult<F> = self.generic_request(query.clone()).await?; Ok(response) } /// Create a Subscription that will yield file changes as they occur in /// real time. /// The `F` type is a struct defined by the /// [query_result_type!](macro.query_result_type.html) macro, /// or, if you want only the file name from the results, the /// [NameOnly](struct.NameOnly.html) struct. /// /// Returns two pieces of information: /// * A [Subscription](struct.Subscription.html) handle that can be used to yield changes /// as they are observed by watchman /// * A [SubscribeResponse](pdu/struct.SubscribeResponse.html) that contains some data about the /// state of the watch at the time the subscription was /// initiated pub async fn subscribe<F>( &self, root: &ResolvedRoot, query: SubscribeRequest, ) -> Result<(Subscription<F>, SubscribeResponse), Error> where F: serde::de::DeserializeOwned + std::fmt::Debug + Clone + QueryFieldList, { let name = format!( "sub-[{}]-{}", std::env::args() .next() .unwrap_or_else(|| "<no-argv-0>".to_string()), SUB_ID.fetch_add(1, Ordering::Relaxed) ); let query = SubscribeCommand( "subscribe", root.root.clone(), name.clone(), SubscribeRequest { relative_root: root.relative.clone(), fields: F::field_list(), ..query }, ); let (tx, responses) = tokio::sync::mpsc::unbounded_channel(); { let inner = self.inner.lock().await; inner .request_tx .send(TaskItem::RegisterSubscription(name.clone(), tx)) .await .map_err(Error::generic)?; } let subscription = Subscription::<F> { name, inner: Arc::clone(&self.inner), root: root.clone(), responses, _phantom: PhantomData, }; let response: SubscribeResponse = self.generic_request(query).await?; Ok((subscription, response)) } /// Expand a set of globs into the set of matching file names. /// The globs must be relative to the `root` parameter. /// The returned file names are all relative to the `root` parameter. pub async fn glob(&self, root: &ResolvedRoot, globs: &[&str]) -> Result<Vec<PathBuf>, Error> { let response: QueryResult<NameOnly> = self .query( root, QueryRequestCommon { relative_root: root.relative.clone(), glob: Some(globs.iter().map(|&s| s.to_string()).collect()), ..Default::default() }, ) .await?; Ok(response .files .unwrap_or_else(Vec::new) .into_iter() .map(|f| f.name.into_inner()) .collect()) } /// Returns the current clock value for a watched root. /// If `sync_timeout` is `SyncTimeout::DisableCookie` then the instantaneous /// clock value is returned without using a sync cookie. /// /// Otherwise, a sync cookie will be created and the server will wait /// for up to the associated `sync_timeout` duration to observe it. /// If that timeout is reached, this method will yield an error. /// /// When should you use a cookie? If you need to a clock value that is /// guaranteed to reflect any filesystem changes that happened before /// a given point in time you should use a sync cookie. /// /// ## See also: /// * <https://facebook.github.io/watchman/docs/cmd/clock.html> /// * <https://facebook.github.io/watchman/docs/cookies.html> pub async fn clock( &self, root: &ResolvedRoot, sync_timeout: SyncTimeout, ) -> Result<ClockSpec, Error> { let response: ClockResponse = self .generic_request(ClockRequest( "clock", root.root.clone(), ClockRequestParams { sync_timeout }, )) .await?; Ok(response.clock) } } #[cfg(test)] mod tests { use super::*; #[test] fn connection_builder_paths() { let builder = Connector::new().unix_domain_socket("/some/path"); assert_eq!(builder.unix_domain, Some(PathBuf::from("/some/path"))); } }