Download rust-analyzer from GitHub

Cargo.lock

@@ -5741,6 +5741,7 @@ name = "zed"
 version = "0.15.2"
 dependencies = [
  "anyhow",
+ "async-compression",
  "async-recursion",
  "async-trait",
  "chat_panel",

crates/language/src/language.rs

@@ -8,7 +8,10 @@ mod tests;
 
 use anyhow::{anyhow, Result};
 use collections::HashSet;
-use futures::future::BoxFuture;
+use futures::{
+    future::{BoxFuture, Shared},
+    FutureExt,
+};
 use gpui::{AppContext, Task};
 use highlight_map::HighlightMap;
 use lazy_static::lazy_static;
@@ -55,8 +58,8 @@ pub trait ToLspPosition {
     fn to_lsp_position(self) -> lsp::Position;
 }
 
-pub trait LspPostProcessor: 'static + Send + Sync {
+pub trait LspExt: 'static + Send + Sync {
-    fn download_language_server(&self) -> BoxFuture<'static, Result<PathBuf>>;
+    fn server_bin_path(&self) -> BoxFuture<'static, Option<PathBuf>>;
     fn process_diagnostics(&self, diagnostics: &mut lsp::PublishDiagnosticsParams);
     fn label_for_completion(
         &self,
@@ -86,7 +89,6 @@ pub struct LanguageConfig {
 
 #[derive(Default, Deserialize)]
 pub struct LanguageServerConfig {
-    pub binary: String,
     pub disk_based_diagnostic_sources: HashSet<String>,
     pub disk_based_diagnostics_progress_token: Option<String>,
     #[cfg(any(test, feature = "test-support"))]
@@ -112,7 +114,8 @@ pub struct BracketPair {
 pub struct Language {
     pub(crate) config: LanguageConfig,
     pub(crate) grammar: Option<Arc<Grammar>>,
-    pub(crate) lsp_post_processor: Option<Box<dyn LspPostProcessor>>,
+    pub(crate) lsp_ext: Option<Box<dyn LspExt>>,
+    lsp_binary_path: Mutex<Option<Shared<BoxFuture<'static, Option<PathBuf>>>>>,
 }
 
 pub struct Grammar {
@@ -179,7 +182,8 @@ impl Language {
                     highlight_map: Default::default(),
                 })
             }),
-            lsp_post_processor: None,
+            lsp_ext: None,
+            lsp_binary_path: Default::default(),
         }
     }
 
@@ -223,8 +227,8 @@ impl Language {
         Ok(self)
     }
 
-    pub fn with_lsp_post_processor(mut self, processor: impl LspPostProcessor) -> Self {
+    pub fn with_lsp_ext(mut self, processor: impl LspExt) -> Self {
-        self.lsp_post_processor = Some(Box::new(processor));
+        self.lsp_ext = Some(Box::new(processor));
         self
     }
 
@@ -241,8 +245,8 @@ impl Language {
         root_path: Arc<Path>,
         cx: &AppContext,
     ) -> Task<Result<Option<Arc<lsp::LanguageServer>>>> {
-        if let Some(config) = &self.config.language_server {
         #[cfg(any(test, feature = "test-support"))]
+        if let Some(config) = &self.config.language_server {
             if let Some(fake_config) = &config.fake_config {
                 use postage::prelude::Stream;
 
@@ -266,19 +270,20 @@ impl Language {
 
                 return Task::ready(Ok(Some(server.clone())));
             }
+        }
 
         let background = cx.background().clone();
         let server_binary_path = self
-                .download_language_server()
+            .lsp_binary_path()
-                .ok_or_else(|| anyhow!("cannot download language server"));
+            .ok_or_else(|| anyhow!("cannot locate or download language server"));
         cx.background().spawn(async move {
-                let server_binary_path = server_binary_path?.await?;
+            if let Some(server_binary_path) = server_binary_path?.await {
                 let server = lsp::LanguageServer::new(&server_binary_path, &root_path, background)?;
                 Ok(Some(server))
-            })
             } else {
-            Task::ready(Ok(None))
+                Ok(None)
             }
+        })
     }
 
     pub fn disk_based_diagnostic_sources(&self) -> Option<&HashSet<String>> {
@@ -296,7 +301,7 @@ impl Language {
     }
 
     pub fn process_diagnostics(&self, diagnostics: &mut lsp::PublishDiagnosticsParams) {
-        if let Some(processor) = self.lsp_post_processor.as_ref() {
+        if let Some(processor) = self.lsp_ext.as_ref() {
             processor.process_diagnostics(diagnostics);
         }
     }
@@ -305,7 +310,7 @@ impl Language {
         &self,
         completion: &lsp::CompletionItem,
     ) -> Option<CompletionLabel> {
-        self.lsp_post_processor
+        self.lsp_ext
             .as_ref()?
             .label_for_completion(completion, self)
     }
@@ -331,10 +336,17 @@ impl Language {
         result
     }
 
-    fn download_language_server(&self) -> Option<impl Future<Output = Result<PathBuf>>> {
+    fn lsp_binary_path(&self) -> Option<impl Future<Output = Option<PathBuf>>> {
-        self.lsp_post_processor
+        if let Some(lsp_ext) = self.lsp_ext.as_ref() {
-            .as_ref()
+            Some(
-            .map(|processor| processor.download_language_server())
+                self.lsp_binary_path
+                    .lock()
+                    .get_or_insert_with(|| lsp_ext.server_bin_path().shared())
+                    .clone(),
+            )
+        } else {
+            None
+        }
     }
 
     pub fn brackets(&self) -> &[BracketPair] {

crates/zed/Cargo.toml

@@ -55,6 +55,7 @@ theme_selector = { path = "../theme_selector" }
 util = { path = "../util" }
 workspace = { path = "../workspace" }
 anyhow = "1.0.38"
+async-compression = { version = "0.3", features = ["gzip", "futures-bufread"] }
 async-recursion = "0.3"
 async-trait = "0.1"
 crossbeam-channel = "0.5.0"

crates/zed/languages/rust/config.toml

@@ -11,6 +11,5 @@ brackets = [
 ]
 
 [language_server]
-binary = "rust-analyzer"
 disk_based_diagnostic_sources = ["rustc"]
 disk_based_diagnostics_progress_token = "rustAnalyzer/cargo check"

crates/zed/src/language.rs

@@ -1,22 +1,98 @@
-use anyhow::Result;
+use anyhow::anyhow;
-use futures::future::BoxFuture;
+use async_compression::futures::bufread::GzipDecoder;
+use client::http;
+use futures::{future::BoxFuture, FutureExt, StreamExt};
 pub use language::*;
 use lazy_static::lazy_static;
 use regex::Regex;
 use rust_embed::RustEmbed;
-use std::borrow::Cow;
+use serde::Deserialize;
-use std::path::PathBuf;
+use smol::fs::{self, File};
-use std::{str, sync::Arc};
+use std::{borrow::Cow, env::consts, path::PathBuf, str, sync::Arc};
+use util::{ResultExt, TryFutureExt};
 
 #[derive(RustEmbed)]
 #[folder = "languages"]
 struct LanguageDir;
 
-struct RustPostProcessor;
+struct RustLsp;
 
-impl LspPostProcessor for RustPostProcessor {
+#[derive(Deserialize)]
-    fn download_language_server(&self) -> BoxFuture<'static, Result<PathBuf>> {
+struct GithubRelease {
-        todo!()
+    name: String,
+    assets: Vec<GithubReleaseAsset>,
+}
+
+#[derive(Deserialize)]
+struct GithubReleaseAsset {
+    name: String,
+    browser_download_url: http::Url,
+}
+
+impl RustLsp {
+    async fn download(destination_dir_path: PathBuf) -> anyhow::Result<PathBuf> {
+        let client = surf::client().with(surf::middleware::Redirect::default());
+        let release = client
+            .get("https://api.github.com/repos/rust-analyzer/rust-analyzer/releases/latest")
+            .recv_json::<GithubRelease>()
+            .await
+            .map_err(|err| anyhow!("error getting latest release: {}", err))?;
+        let release_name = format!("rust-analyzer-{}-apple-darwin.gz", consts::ARCH);
+        let asset = release
+            .assets
+            .iter()
+            .find(|asset| asset.name == release_name)
+            .ok_or_else(|| anyhow!("no release found matching {:?}", release_name))?;
+
+        let destination_path = destination_dir_path.join(format!("rust-analyzer-{}", release.name));
+        if fs::metadata(&destination_path).await.is_ok() {
+            let response = client
+                .get(&asset.browser_download_url)
+                .send()
+                .await
+                .map_err(|err| anyhow!("error downloading release: {}", err))?;
+            let decompressed_bytes = GzipDecoder::new(response);
+            let mut file = File::create(&destination_path).await?;
+            futures::io::copy(decompressed_bytes, &mut file).await?;
+            fs::set_permissions(
+                &destination_path,
+                <fs::Permissions as fs::unix::PermissionsExt>::from_mode(0o755),
+            )
+            .await?;
+        }
+
+        Ok::<_, anyhow::Error>(destination_path)
+    }
+}
+
+impl LspExt for RustLsp {
+    fn server_bin_path(&self) -> BoxFuture<'static, Option<PathBuf>> {
+        async move {
+            let destination_dir_path = dirs::home_dir()
+                .ok_or_else(|| anyhow!("can't determine home directory"))?
+                .join(".zed/rust-analyzer");
+            fs::create_dir_all(&destination_dir_path).await?;
+
+            let mut server_bin_path = Self::download(destination_dir_path.clone()).await.log_err();
+            if let Some(mut entries) = fs::read_dir(&destination_dir_path).await.log_err() {
+                while let Some(entry) = entries.next().await {
+                    if let Some(entry) = entry.log_err() {
+                        let entry_path = entry.path();
+                        if let Some(downloaded_server_path) = server_bin_path.as_ref() {
+                            if downloaded_server_path != entry_path.as_path() {
+                                fs::remove_file(entry_path).await.log_err();
+                            }
+                        } else {
+                            server_bin_path = Some(entry_path);
+                        }
+                    }
+                }
+            }
+
+            server_bin_path.ok_or_else(|| anyhow!("could not locate or download server"))
+        }
+        .log_err()
+        .boxed()
     }
 
     fn process_diagnostics(&self, params: &mut lsp::PublishDiagnosticsParams) {
@@ -138,7 +214,7 @@ fn rust() -> Language {
         .unwrap()
         .with_outline_query(load_query("rust/outline.scm").as_ref())
         .unwrap()
-        .with_lsp_post_processor(RustPostProcessor)
+        .with_lsp_ext(RustLsp)
 }
 
 fn markdown() -> Language {
@@ -160,7 +236,7 @@ fn load_query(path: &str) -> Cow<'static, str> {
 mod tests {
     use super::*;
     use gpui::color::Color;
-    use language::LspPostProcessor;
+    use language::LspExt;
     use theme::SyntaxTheme;
 
     #[test]
@@ -187,7 +263,7 @@ mod tests {
                 },
             ],
         };
-        RustPostProcessor.process_diagnostics(&mut params);
+        RustLsp.process_diagnostics(&mut params);
 
         assert_eq!(params.diagnostics[0].message, "use of moved value `a`");