extension_builder.rs

  1use crate::{
  2    parse_wasm_extension_version, ExtensionLibraryKind, ExtensionManifest, GrammarManifestEntry,
  3};
  4use anyhow::{anyhow, bail, Context as _, Result};
  5use async_compression::futures::bufread::GzipDecoder;
  6use async_tar::Archive;
  7use futures::io::BufReader;
  8use futures::AsyncReadExt;
  9use http_client::{self, AsyncBody, HttpClient};
 10use serde::Deserialize;
 11use std::{
 12    env, fs, mem,
 13    path::{Path, PathBuf},
 14    process::Stdio,
 15    sync::Arc,
 16};
 17use wasm_encoder::{ComponentSectionId, Encode as _, RawSection, Section as _};
 18use wasmparser::Parser;
 19use wit_component::ComponentEncoder;
 20
 21/// Currently, we compile with Rust's `wasm32-wasip1` target, which works with WASI `preview1`.
 22/// But the WASM component model is based on WASI `preview2`. So we need an 'adapter' WASM
 23/// module, which implements the `preview1` interface in terms of `preview2`.
 24///
 25/// Once Rust 1.78 is released, there will be a `wasm32-wasip2` target available, so we will
 26/// not need the adapter anymore.
 27const RUST_TARGET: &str = "wasm32-wasip1";
 28const WASI_ADAPTER_URL: &str =
 29    "https://github.com/bytecodealliance/wasmtime/releases/download/v18.0.2/wasi_snapshot_preview1.reactor.wasm";
 30
 31/// Compiling Tree-sitter parsers from C to WASM requires Clang 17, and a WASM build of libc
 32/// and clang's runtime library. The `wasi-sdk` provides these binaries.
 33///
 34/// Once Clang 17 and its wasm target are available via system package managers, we won't need
 35/// to download this.
 36const WASI_SDK_URL: &str = "https://github.com/WebAssembly/wasi-sdk/releases/download/wasi-sdk-21/";
 37const WASI_SDK_ASSET_NAME: Option<&str> = if cfg!(target_os = "macos") {
 38    Some("wasi-sdk-21.0-macos.tar.gz")
 39} else if cfg!(any(target_os = "linux", target_os = "freebsd")) {
 40    Some("wasi-sdk-21.0-linux.tar.gz")
 41} else if cfg!(target_os = "windows") {
 42    Some("wasi-sdk-21.0.m-mingw.tar.gz")
 43} else {
 44    None
 45};
 46
 47pub struct ExtensionBuilder {
 48    cache_dir: PathBuf,
 49    pub http: Arc<dyn HttpClient>,
 50}
 51
 52pub struct CompileExtensionOptions {
 53    pub release: bool,
 54}
 55
 56#[derive(Deserialize)]
 57struct CargoToml {
 58    package: CargoTomlPackage,
 59}
 60
 61#[derive(Deserialize)]
 62struct CargoTomlPackage {
 63    name: String,
 64}
 65
 66impl ExtensionBuilder {
 67    pub fn new(http_client: Arc<dyn HttpClient>, cache_dir: PathBuf) -> Self {
 68        Self {
 69            cache_dir,
 70            http: http_client,
 71        }
 72    }
 73
 74    pub async fn compile_extension(
 75        &self,
 76        extension_dir: &Path,
 77        extension_manifest: &mut ExtensionManifest,
 78        options: CompileExtensionOptions,
 79    ) -> Result<()> {
 80        populate_defaults(extension_manifest, extension_dir)?;
 81
 82        if extension_dir.is_relative() {
 83            bail!(
 84                "extension dir {} is not an absolute path",
 85                extension_dir.display()
 86            );
 87        }
 88
 89        fs::create_dir_all(&self.cache_dir).context("failed to create cache dir")?;
 90
 91        if extension_manifest.lib.kind == Some(ExtensionLibraryKind::Rust) {
 92            log::info!("compiling Rust extension {}", extension_dir.display());
 93            self.compile_rust_extension(extension_dir, extension_manifest, options)
 94                .await
 95                .context("failed to compile Rust extension")?;
 96            log::info!("compiled Rust extension {}", extension_dir.display());
 97        }
 98
 99        for (grammar_name, grammar_metadata) in &extension_manifest.grammars {
100            log::info!(
101                "compiling grammar {grammar_name} for extension {}",
102                extension_dir.display()
103            );
104            self.compile_grammar(extension_dir, grammar_name.as_ref(), grammar_metadata)
105                .await
106                .with_context(|| format!("failed to compile grammar '{grammar_name}'"))?;
107            log::info!(
108                "compiled grammar {grammar_name} for extension {}",
109                extension_dir.display()
110            );
111        }
112
113        log::info!("finished compiling extension {}", extension_dir.display());
114        Ok(())
115    }
116
117    async fn compile_rust_extension(
118        &self,
119        extension_dir: &Path,
120        manifest: &mut ExtensionManifest,
121        options: CompileExtensionOptions,
122    ) -> Result<(), anyhow::Error> {
123        self.install_rust_wasm_target_if_needed()?;
124        let adapter_bytes = self.install_wasi_preview1_adapter_if_needed().await?;
125
126        let cargo_toml_content = fs::read_to_string(extension_dir.join("Cargo.toml"))?;
127        let cargo_toml: CargoToml = toml::from_str(&cargo_toml_content)?;
128
129        log::info!(
130            "compiling Rust crate for extension {}",
131            extension_dir.display()
132        );
133        let output = util::command::new_std_command("cargo")
134            .args(["build", "--target", RUST_TARGET])
135            .args(options.release.then_some("--release"))
136            .arg("--target-dir")
137            .arg(extension_dir.join("target"))
138            // WASI builds do not work with sccache and just stuck, so disable it.
139            .env("RUSTC_WRAPPER", "")
140            .current_dir(extension_dir)
141            .output()
142            .context("failed to run `cargo`")?;
143        if !output.status.success() {
144            bail!(
145                "failed to build extension {}",
146                String::from_utf8_lossy(&output.stderr)
147            );
148        }
149
150        log::info!(
151            "compiled Rust crate for extension {}",
152            extension_dir.display()
153        );
154
155        let mut wasm_path = PathBuf::from(extension_dir);
156        wasm_path.extend([
157            "target",
158            RUST_TARGET,
159            if options.release { "release" } else { "debug" },
160            &cargo_toml
161                .package
162                .name
163                // The wasm32-wasip1 target normalizes `-` in package names to `_` in the resulting `.wasm` file.
164                .replace('-', "_"),
165        ]);
166        wasm_path.set_extension("wasm");
167
168        let wasm_bytes = fs::read(&wasm_path)
169            .with_context(|| format!("failed to read output module `{}`", wasm_path.display()))?;
170
171        let mut encoder = ComponentEncoder::default()
172            .module(&wasm_bytes)?
173            .adapter("wasi_snapshot_preview1", &adapter_bytes)
174            .context("failed to load adapter module")?
175            .validate(true);
176
177        log::info!(
178            "encoding wasm component for extension {}",
179            extension_dir.display()
180        );
181
182        let component_bytes = encoder
183            .encode()
184            .context("failed to encode wasm component")?;
185
186        let component_bytes = self
187            .strip_custom_sections(&component_bytes)
188            .context("failed to strip debug sections from wasm component")?;
189
190        let wasm_extension_api_version =
191            parse_wasm_extension_version(&manifest.id, &component_bytes)
192                .context("compiled wasm did not contain a valid zed extension api version")?;
193        manifest.lib.version = Some(wasm_extension_api_version);
194
195        let extension_file = extension_dir.join("extension.wasm");
196        fs::write(extension_file.clone(), &component_bytes)
197            .context("failed to write extension.wasm")?;
198
199        log::info!(
200            "extension {} written to {}",
201            extension_dir.display(),
202            extension_file.display()
203        );
204
205        Ok(())
206    }
207
208    async fn compile_grammar(
209        &self,
210        extension_dir: &Path,
211        grammar_name: &str,
212        grammar_metadata: &GrammarManifestEntry,
213    ) -> Result<()> {
214        let clang_path = self.install_wasi_sdk_if_needed().await?;
215
216        let mut grammar_repo_dir = extension_dir.to_path_buf();
217        grammar_repo_dir.extend(["grammars", grammar_name]);
218
219        let mut grammar_wasm_path = grammar_repo_dir.clone();
220        grammar_wasm_path.set_extension("wasm");
221
222        log::info!("checking out {grammar_name} parser");
223        self.checkout_repo(
224            &grammar_repo_dir,
225            &grammar_metadata.repository,
226            &grammar_metadata.rev,
227        )?;
228
229        let base_grammar_path = grammar_metadata
230            .path
231            .as_ref()
232            .map(|path| grammar_repo_dir.join(path))
233            .unwrap_or(grammar_repo_dir);
234
235        let src_path = base_grammar_path.join("src");
236        let parser_path = src_path.join("parser.c");
237        let scanner_path = src_path.join("scanner.c");
238
239        log::info!("compiling {grammar_name} parser");
240        let clang_output = util::command::new_std_command(&clang_path)
241            .args(["-fPIC", "-shared", "-Os"])
242            .arg(format!("-Wl,--export=tree_sitter_{grammar_name}"))
243            .arg("-o")
244            .arg(&grammar_wasm_path)
245            .arg("-I")
246            .arg(&src_path)
247            .arg(&parser_path)
248            .args(scanner_path.exists().then_some(scanner_path))
249            .output()
250            .context("failed to run clang")?;
251
252        if !clang_output.status.success() {
253            bail!(
254                "failed to compile {} parser with clang: {}",
255                grammar_name,
256                String::from_utf8_lossy(&clang_output.stderr),
257            );
258        }
259
260        Ok(())
261    }
262
263    fn checkout_repo(&self, directory: &Path, url: &str, rev: &str) -> Result<()> {
264        let git_dir = directory.join(".git");
265
266        if directory.exists() {
267            let remotes_output = util::command::new_std_command("git")
268                .arg("--git-dir")
269                .arg(&git_dir)
270                .args(["remote", "-v"])
271                .output()?;
272            let has_remote = remotes_output.status.success()
273                && String::from_utf8_lossy(&remotes_output.stdout)
274                    .lines()
275                    .any(|line| {
276                        let mut parts = line.split(|c: char| c.is_whitespace());
277                        parts.next() == Some("origin") && parts.any(|part| part == url)
278                    });
279            if !has_remote {
280                bail!(
281                    "grammar directory '{}' already exists, but is not a git clone of '{}'",
282                    directory.display(),
283                    url
284                );
285            }
286        } else {
287            fs::create_dir_all(directory).with_context(|| {
288                format!("failed to create grammar directory {}", directory.display(),)
289            })?;
290            let init_output = util::command::new_std_command("git")
291                .arg("init")
292                .current_dir(directory)
293                .output()?;
294            if !init_output.status.success() {
295                bail!(
296                    "failed to run `git init` in directory '{}'",
297                    directory.display()
298                );
299            }
300
301            let remote_add_output = util::command::new_std_command("git")
302                .arg("--git-dir")
303                .arg(&git_dir)
304                .args(["remote", "add", "origin", url])
305                .output()
306                .context("failed to execute `git remote add`")?;
307            if !remote_add_output.status.success() {
308                bail!(
309                    "failed to add remote {url} for git repository {}",
310                    git_dir.display()
311                );
312            }
313        }
314
315        let fetch_output = util::command::new_std_command("git")
316            .arg("--git-dir")
317            .arg(&git_dir)
318            .args(["fetch", "--depth", "1", "origin", rev])
319            .output()
320            .context("failed to execute `git fetch`")?;
321
322        let checkout_output = util::command::new_std_command("git")
323            .arg("--git-dir")
324            .arg(&git_dir)
325            .args(["checkout", rev])
326            .current_dir(directory)
327            .output()
328            .context("failed to execute `git checkout`")?;
329        if !checkout_output.status.success() {
330            if !fetch_output.status.success() {
331                bail!(
332                    "failed to fetch revision {} in directory '{}'",
333                    rev,
334                    directory.display()
335                );
336            }
337            bail!(
338                "failed to checkout revision {} in directory '{}': {}",
339                rev,
340                directory.display(),
341                String::from_utf8_lossy(&checkout_output.stderr)
342            );
343        }
344
345        Ok(())
346    }
347
348    fn install_rust_wasm_target_if_needed(&self) -> Result<()> {
349        let rustc_output = util::command::new_std_command("rustc")
350            .arg("--print")
351            .arg("sysroot")
352            .output()
353            .context("failed to run rustc")?;
354        if !rustc_output.status.success() {
355            bail!(
356                "failed to retrieve rust sysroot: {}",
357                String::from_utf8_lossy(&rustc_output.stderr)
358            );
359        }
360
361        let sysroot = PathBuf::from(String::from_utf8(rustc_output.stdout)?.trim());
362        if sysroot.join("lib/rustlib").join(RUST_TARGET).exists() {
363            return Ok(());
364        }
365
366        let output = util::command::new_std_command("rustup")
367            .args(["target", "add", RUST_TARGET])
368            .stderr(Stdio::piped())
369            .stdout(Stdio::inherit())
370            .output()
371            .context("failed to run `rustup target add`")?;
372        if !output.status.success() {
373            bail!(
374                "failed to install the `{RUST_TARGET}` target: {}",
375                String::from_utf8_lossy(&rustc_output.stderr)
376            );
377        }
378
379        Ok(())
380    }
381
382    async fn install_wasi_preview1_adapter_if_needed(&self) -> Result<Vec<u8>> {
383        let cache_path = self.cache_dir.join("wasi_snapshot_preview1.reactor.wasm");
384        if let Ok(content) = fs::read(&cache_path) {
385            if Parser::is_core_wasm(&content) {
386                return Ok(content);
387            }
388        }
389
390        fs::remove_file(&cache_path).ok();
391
392        log::info!(
393            "downloading wasi adapter module to {}",
394            cache_path.display()
395        );
396        let mut response = self
397            .http
398            .get(WASI_ADAPTER_URL, AsyncBody::default(), true)
399            .await?;
400
401        let mut content = Vec::new();
402        let mut body = BufReader::new(response.body_mut());
403        body.read_to_end(&mut content).await?;
404
405        fs::write(&cache_path, &content)
406            .with_context(|| format!("failed to save file {}", cache_path.display()))?;
407
408        if !Parser::is_core_wasm(&content) {
409            bail!("downloaded wasi adapter is invalid");
410        }
411        Ok(content)
412    }
413
414    async fn install_wasi_sdk_if_needed(&self) -> Result<PathBuf> {
415        let url = if let Some(asset_name) = WASI_SDK_ASSET_NAME {
416            format!("{WASI_SDK_URL}/{asset_name}")
417        } else {
418            bail!("wasi-sdk is not available for platform {}", env::consts::OS);
419        };
420
421        let wasi_sdk_dir = self.cache_dir.join("wasi-sdk");
422        let mut clang_path = wasi_sdk_dir.clone();
423        clang_path.extend(["bin", &format!("clang{}", env::consts::EXE_SUFFIX)]);
424
425        if fs::metadata(&clang_path).map_or(false, |metadata| metadata.is_file()) {
426            return Ok(clang_path);
427        }
428
429        let mut tar_out_dir = wasi_sdk_dir.clone();
430        tar_out_dir.set_extension("archive");
431
432        fs::remove_dir_all(&wasi_sdk_dir).ok();
433        fs::remove_dir_all(&tar_out_dir).ok();
434
435        log::info!("downloading wasi-sdk to {}", wasi_sdk_dir.display());
436        let mut response = self.http.get(&url, AsyncBody::default(), true).await?;
437        let body = BufReader::new(response.body_mut());
438        let body = GzipDecoder::new(body);
439        let tar = Archive::new(body);
440
441        tar.unpack(&tar_out_dir)
442            .await
443            .context("failed to unpack wasi-sdk archive")?;
444
445        let inner_dir = fs::read_dir(&tar_out_dir)?
446            .next()
447            .ok_or_else(|| anyhow!("no content"))?
448            .context("failed to read contents of extracted wasi archive directory")?
449            .path();
450        fs::rename(&inner_dir, &wasi_sdk_dir).context("failed to move extracted wasi dir")?;
451        fs::remove_dir_all(&tar_out_dir).ok();
452
453        Ok(clang_path)
454    }
455
456    // This was adapted from:
457    // https://github.com/bytecodealliance/wasm-tools/blob/1791a8f139722e9f8679a2bd3d8e423e55132b22/src/bin/wasm-tools/strip.rs
458    fn strip_custom_sections(&self, input: &Vec<u8>) -> Result<Vec<u8>> {
459        use wasmparser::Payload::*;
460
461        let strip_custom_section = |name: &str| name.starts_with(".debug");
462
463        let mut output = Vec::new();
464        let mut stack = Vec::new();
465
466        for payload in Parser::new(0).parse_all(input) {
467            let payload = payload?;
468            let component_header = wasm_encoder::Component::HEADER;
469            let module_header = wasm_encoder::Module::HEADER;
470
471            // Track nesting depth, so that we don't mess with inner producer sections:
472            match payload {
473                Version { encoding, .. } => {
474                    output.extend_from_slice(match encoding {
475                        wasmparser::Encoding::Component => &component_header,
476                        wasmparser::Encoding::Module => &module_header,
477                    });
478                }
479                ModuleSection { .. } | ComponentSection { .. } => {
480                    stack.push(mem::take(&mut output));
481                    continue;
482                }
483                End { .. } => {
484                    let mut parent = match stack.pop() {
485                        Some(c) => c,
486                        None => break,
487                    };
488                    if output.starts_with(&component_header) {
489                        parent.push(ComponentSectionId::Component as u8);
490                        output.encode(&mut parent);
491                    } else {
492                        parent.push(ComponentSectionId::CoreModule as u8);
493                        output.encode(&mut parent);
494                    }
495                    output = parent;
496                }
497                _ => {}
498            }
499
500            if let CustomSection(c) = &payload {
501                if strip_custom_section(c.name()) {
502                    continue;
503                }
504            }
505
506            if let Some((id, range)) = payload.as_section() {
507                RawSection {
508                    id,
509                    data: &input[range],
510                }
511                .append_to(&mut output);
512            }
513        }
514
515        Ok(output)
516    }
517}
518
519fn populate_defaults(manifest: &mut ExtensionManifest, extension_path: &Path) -> Result<()> {
520    // For legacy extensions on the v0 schema (aka, using `extension.json`), clear out any existing
521    // contents of the computed fields, since we don't care what the existing values are.
522    if manifest.schema_version.is_v0() {
523        manifest.languages.clear();
524        manifest.grammars.clear();
525        manifest.themes.clear();
526    }
527
528    let cargo_toml_path = extension_path.join("Cargo.toml");
529    if cargo_toml_path.exists() {
530        manifest.lib.kind = Some(ExtensionLibraryKind::Rust);
531    }
532
533    let languages_dir = extension_path.join("languages");
534    if languages_dir.exists() {
535        for entry in fs::read_dir(&languages_dir).context("failed to list languages dir")? {
536            let entry = entry?;
537            let language_dir = entry.path();
538            let config_path = language_dir.join("config.toml");
539            if config_path.exists() {
540                let relative_language_dir =
541                    language_dir.strip_prefix(extension_path)?.to_path_buf();
542                if !manifest.languages.contains(&relative_language_dir) {
543                    manifest.languages.push(relative_language_dir);
544                }
545            }
546        }
547    }
548
549    let themes_dir = extension_path.join("themes");
550    if themes_dir.exists() {
551        for entry in fs::read_dir(&themes_dir).context("failed to list themes dir")? {
552            let entry = entry?;
553            let theme_path = entry.path();
554            if theme_path.extension() == Some("json".as_ref()) {
555                let relative_theme_path = theme_path.strip_prefix(extension_path)?.to_path_buf();
556                if !manifest.themes.contains(&relative_theme_path) {
557                    manifest.themes.push(relative_theme_path);
558                }
559            }
560        }
561    }
562
563    let icon_themes_dir = extension_path.join("icon_themes");
564    if icon_themes_dir.exists() {
565        for entry in fs::read_dir(&icon_themes_dir).context("failed to list icon themes dir")? {
566            let entry = entry?;
567            let icon_theme_path = entry.path();
568            if icon_theme_path.extension() == Some("json".as_ref()) {
569                let relative_icon_theme_path =
570                    icon_theme_path.strip_prefix(extension_path)?.to_path_buf();
571                if !manifest.icon_themes.contains(&relative_icon_theme_path) {
572                    manifest.icon_themes.push(relative_icon_theme_path);
573                }
574            }
575        }
576    }
577
578    let snippets_json_path = extension_path.join("snippets.json");
579    if snippets_json_path.exists() {
580        manifest.snippets = Some(snippets_json_path);
581    }
582
583    // For legacy extensions on the v0 schema (aka, using `extension.json`), we want to populate the grammars in
584    // the manifest using the contents of the `grammars` directory.
585    if manifest.schema_version.is_v0() {
586        let grammars_dir = extension_path.join("grammars");
587        if grammars_dir.exists() {
588            for entry in fs::read_dir(&grammars_dir).context("failed to list grammars dir")? {
589                let entry = entry?;
590                let grammar_path = entry.path();
591                if grammar_path.extension() == Some("toml".as_ref()) {
592                    #[derive(Deserialize)]
593                    struct GrammarConfigToml {
594                        pub repository: String,
595                        pub commit: String,
596                        #[serde(default)]
597                        pub path: Option<String>,
598                    }
599
600                    let grammar_config = fs::read_to_string(&grammar_path)?;
601                    let grammar_config: GrammarConfigToml = toml::from_str(&grammar_config)?;
602
603                    let grammar_name = grammar_path
604                        .file_stem()
605                        .and_then(|stem| stem.to_str())
606                        .ok_or_else(|| anyhow!("no grammar name"))?;
607                    if !manifest.grammars.contains_key(grammar_name) {
608                        manifest.grammars.insert(
609                            grammar_name.into(),
610                            GrammarManifestEntry {
611                                repository: grammar_config.repository,
612                                rev: grammar_config.commit,
613                                path: grammar_config.path,
614                            },
615                        );
616                    }
617                }
618            }
619        }
620    }
621
622    Ok(())
623}