extension_builder.rs

  1use crate::{
  2    ExtensionLibraryKind, ExtensionManifest, GrammarManifestEntry, parse_wasm_extension_version,
  3};
  4use anyhow::{Context as _, Result, bail, ensure};
  5use async_compression::futures::bufread::GzipDecoder;
  6use async_tar::Archive;
  7use futures::io::BufReader;
  8use heck::ToSnakeCase;
  9use http_client::{self, AsyncBody, HttpClient};
 10use serde::Deserialize;
 11use std::{
 12    env, fs, mem,
 13    path::{Path, PathBuf},
 14    process::Stdio,
 15    str::FromStr,
 16    sync::Arc,
 17};
 18use wasm_encoder::{ComponentSectionId, Encode as _, RawSection, Section as _};
 19use wasmparser::Parser;
 20
 21/// Currently, we compile with Rust's `wasm32-wasip2` target, which works with WASI `preview2` and the component model.
 22const RUST_TARGET: &str = "wasm32-wasip2";
 23
 24/// Compiling Tree-sitter parsers from C to WASM requires Clang 17, and a WASM build of libc
 25/// and clang's runtime library. The `wasi-sdk` provides these binaries.
 26///
 27/// Once Clang 17 and its wasm target are available via system package managers, we won't need
 28/// to download this.
 29const WASI_SDK_URL: &str = "https://github.com/WebAssembly/wasi-sdk/releases/download/wasi-sdk-25/";
 30const WASI_SDK_ASSET_NAME: Option<&str> = if cfg!(all(target_os = "macos", target_arch = "x86_64"))
 31{
 32    Some("wasi-sdk-25.0-x86_64-macos.tar.gz")
 33} else if cfg!(all(target_os = "macos", target_arch = "aarch64")) {
 34    Some("wasi-sdk-25.0-arm64-macos.tar.gz")
 35} else if cfg!(all(target_os = "linux", target_arch = "x86_64")) {
 36    Some("wasi-sdk-25.0-x86_64-linux.tar.gz")
 37} else if cfg!(all(target_os = "linux", target_arch = "aarch64")) {
 38    Some("wasi-sdk-25.0-arm64-linux.tar.gz")
 39} else if cfg!(all(target_os = "freebsd", target_arch = "x86_64")) {
 40    Some("wasi-sdk-25.0-x86_64-linux.tar.gz")
 41} else if cfg!(all(target_os = "freebsd", target_arch = "aarch64")) {
 42    Some("wasi-sdk-25.0-arm64-linux.tar.gz")
 43} else if cfg!(all(target_os = "windows", target_arch = "x86_64")) {
 44    Some("wasi-sdk-25.0-x86_64-windows.tar.gz")
 45} else {
 46    None
 47};
 48
 49pub struct ExtensionBuilder {
 50    cache_dir: PathBuf,
 51    pub http: Arc<dyn HttpClient>,
 52}
 53
 54pub struct CompileExtensionOptions {
 55    pub release: bool,
 56}
 57
 58#[derive(Deserialize)]
 59struct CargoToml {
 60    package: CargoTomlPackage,
 61}
 62
 63#[derive(Deserialize)]
 64struct CargoTomlPackage {
 65    name: String,
 66}
 67
 68impl ExtensionBuilder {
 69    pub fn new(http_client: Arc<dyn HttpClient>, cache_dir: PathBuf) -> Self {
 70        Self {
 71            cache_dir,
 72            http: http_client,
 73        }
 74    }
 75
 76    pub async fn compile_extension(
 77        &self,
 78        extension_dir: &Path,
 79        extension_manifest: &mut ExtensionManifest,
 80        options: CompileExtensionOptions,
 81    ) -> Result<()> {
 82        populate_defaults(extension_manifest, extension_dir)?;
 83
 84        if extension_dir.is_relative() {
 85            bail!(
 86                "extension dir {} is not an absolute path",
 87                extension_dir.display()
 88            );
 89        }
 90
 91        fs::create_dir_all(&self.cache_dir).context("failed to create cache dir")?;
 92
 93        if extension_manifest.lib.kind == Some(ExtensionLibraryKind::Rust) {
 94            log::info!("compiling Rust extension {}", extension_dir.display());
 95            self.compile_rust_extension(extension_dir, extension_manifest, options)
 96                .await
 97                .context("failed to compile Rust extension")?;
 98            log::info!("compiled Rust extension {}", extension_dir.display());
 99        }
100
101        let debug_adapters_dir = extension_dir.join("debug_adapter_schemas");
102        if !extension_manifest.debug_adapters.is_empty() {
103            ensure!(
104                debug_adapters_dir.exists(),
105                "Expected debug adapter schemas directory to exist"
106            );
107        }
108        for debug_adapter_name in &extension_manifest.debug_adapters {
109            let debug_adapter_schema_path = debug_adapters_dir.join(debug_adapter_name.as_ref());
110            let debug_adapter_schema = fs::read_to_string(&debug_adapter_schema_path)
111                .with_context(|| {
112                    format!("failed to read debug adapter schema for `{debug_adapter_name}`")
113                })?;
114            _ = serde_json::Value::from_str(&debug_adapter_schema).with_context(|| {
115                format!("Debug adapter schema for `{debug_adapter_name}` is not a valid JSON")
116            })?;
117        }
118        for (grammar_name, grammar_metadata) in &extension_manifest.grammars {
119            let snake_cased_grammar_name = grammar_name.to_snake_case();
120            if grammar_name.as_ref() != snake_cased_grammar_name.as_str() {
121                bail!(
122                    "grammar name '{grammar_name}' must be written in snake_case: {snake_cased_grammar_name}"
123                );
124            }
125
126            log::info!(
127                "compiling grammar {grammar_name} for extension {}",
128                extension_dir.display()
129            );
130            self.compile_grammar(extension_dir, grammar_name.as_ref(), grammar_metadata)
131                .await
132                .with_context(|| format!("failed to compile grammar '{grammar_name}'"))?;
133            log::info!(
134                "compiled grammar {grammar_name} for extension {}",
135                extension_dir.display()
136            );
137        }
138
139        log::info!("finished compiling extension {}", extension_dir.display());
140        Ok(())
141    }
142
143    async fn compile_rust_extension(
144        &self,
145        extension_dir: &Path,
146        manifest: &mut ExtensionManifest,
147        options: CompileExtensionOptions,
148    ) -> anyhow::Result<()> {
149        self.install_rust_wasm_target_if_needed()?;
150
151        let cargo_toml_content = fs::read_to_string(extension_dir.join("Cargo.toml"))?;
152        let cargo_toml: CargoToml = toml::from_str(&cargo_toml_content)?;
153
154        log::info!(
155            "compiling Rust crate for extension {}",
156            extension_dir.display()
157        );
158        let output = util::command::new_std_command("cargo")
159            .args(["build", "--target", RUST_TARGET])
160            .args(options.release.then_some("--release"))
161            .arg("--target-dir")
162            .arg(extension_dir.join("target"))
163            // WASI builds do not work with sccache and just stuck, so disable it.
164            .env("RUSTC_WRAPPER", "")
165            .current_dir(extension_dir)
166            .output()
167            .context("failed to run `cargo`")?;
168        if !output.status.success() {
169            bail!(
170                "failed to build extension {}",
171                String::from_utf8_lossy(&output.stderr)
172            );
173        }
174
175        log::info!(
176            "compiled Rust crate for extension {}",
177            extension_dir.display()
178        );
179
180        let mut wasm_path = PathBuf::from(extension_dir);
181        wasm_path.extend([
182            "target",
183            RUST_TARGET,
184            if options.release { "release" } else { "debug" },
185            &cargo_toml
186                .package
187                .name
188                // The wasm32-wasip2 target normalizes `-` in package names to `_` in the resulting `.wasm` file.
189                .replace('-', "_"),
190        ]);
191        wasm_path.set_extension("wasm");
192
193        log::info!(
194            "encoding wasm component for extension {}",
195            extension_dir.display()
196        );
197
198        let component_bytes = fs::read(&wasm_path)
199            .with_context(|| format!("failed to read output module `{}`", wasm_path.display()))?;
200
201        let component_bytes = self
202            .strip_custom_sections(&component_bytes)
203            .context("failed to strip debug sections from wasm component")?;
204
205        let wasm_extension_api_version =
206            parse_wasm_extension_version(&manifest.id, &component_bytes)
207                .context("compiled wasm did not contain a valid zed extension api version")?;
208        manifest.lib.version = Some(wasm_extension_api_version);
209
210        let extension_file = extension_dir.join("extension.wasm");
211        fs::write(extension_file.clone(), &component_bytes)
212            .context("failed to write extension.wasm")?;
213
214        log::info!(
215            "extension {} written to {}",
216            extension_dir.display(),
217            extension_file.display()
218        );
219
220        Ok(())
221    }
222
223    async fn compile_grammar(
224        &self,
225        extension_dir: &Path,
226        grammar_name: &str,
227        grammar_metadata: &GrammarManifestEntry,
228    ) -> Result<()> {
229        let clang_path = self.install_wasi_sdk_if_needed().await?;
230
231        let mut grammar_repo_dir = extension_dir.to_path_buf();
232        grammar_repo_dir.extend(["grammars", grammar_name]);
233
234        let mut grammar_wasm_path = grammar_repo_dir.clone();
235        grammar_wasm_path.set_extension("wasm");
236
237        log::info!("checking out {grammar_name} parser");
238        self.checkout_repo(
239            &grammar_repo_dir,
240            &grammar_metadata.repository,
241            &grammar_metadata.rev,
242        )?;
243
244        let base_grammar_path = grammar_metadata
245            .path
246            .as_ref()
247            .map(|path| grammar_repo_dir.join(path))
248            .unwrap_or(grammar_repo_dir);
249
250        let src_path = base_grammar_path.join("src");
251        let parser_path = src_path.join("parser.c");
252        let scanner_path = src_path.join("scanner.c");
253
254        log::info!("compiling {grammar_name} parser");
255        let clang_output = util::command::new_std_command(&clang_path)
256            .args(["-fPIC", "-shared", "-Os"])
257            .arg(format!("-Wl,--export=tree_sitter_{grammar_name}"))
258            .arg("-o")
259            .arg(&grammar_wasm_path)
260            .arg("-I")
261            .arg(&src_path)
262            .arg(&parser_path)
263            .args(scanner_path.exists().then_some(scanner_path))
264            .output()
265            .context("failed to run clang")?;
266
267        if !clang_output.status.success() {
268            bail!(
269                "failed to compile {} parser with clang: {}",
270                grammar_name,
271                String::from_utf8_lossy(&clang_output.stderr),
272            );
273        }
274
275        Ok(())
276    }
277
278    fn checkout_repo(&self, directory: &Path, url: &str, rev: &str) -> Result<()> {
279        let git_dir = directory.join(".git");
280
281        if directory.exists() {
282            let remotes_output = util::command::new_std_command("git")
283                .arg("--git-dir")
284                .arg(&git_dir)
285                .args(["remote", "-v"])
286                .output()?;
287            let has_remote = remotes_output.status.success()
288                && String::from_utf8_lossy(&remotes_output.stdout)
289                    .lines()
290                    .any(|line| {
291                        let mut parts = line.split(|c: char| c.is_whitespace());
292                        parts.next() == Some("origin") && parts.any(|part| part == url)
293                    });
294            if !has_remote {
295                bail!(
296                    "grammar directory '{}' already exists, but is not a git clone of '{}'",
297                    directory.display(),
298                    url
299                );
300            }
301        } else {
302            fs::create_dir_all(directory).with_context(|| {
303                format!("failed to create grammar directory {}", directory.display(),)
304            })?;
305            let init_output = util::command::new_std_command("git")
306                .arg("init")
307                .current_dir(directory)
308                .output()?;
309            if !init_output.status.success() {
310                bail!(
311                    "failed to run `git init` in directory '{}'",
312                    directory.display()
313                );
314            }
315
316            let remote_add_output = util::command::new_std_command("git")
317                .arg("--git-dir")
318                .arg(&git_dir)
319                .args(["remote", "add", "origin", url])
320                .output()
321                .context("failed to execute `git remote add`")?;
322            if !remote_add_output.status.success() {
323                bail!(
324                    "failed to add remote {url} for git repository {}",
325                    git_dir.display()
326                );
327            }
328        }
329
330        let fetch_output = util::command::new_std_command("git")
331            .arg("--git-dir")
332            .arg(&git_dir)
333            .args(["fetch", "--depth", "1", "origin", rev])
334            .output()
335            .context("failed to execute `git fetch`")?;
336
337        let checkout_output = util::command::new_std_command("git")
338            .arg("--git-dir")
339            .arg(&git_dir)
340            .args(["checkout", rev])
341            .current_dir(directory)
342            .output()
343            .context("failed to execute `git checkout`")?;
344        if !checkout_output.status.success() {
345            if !fetch_output.status.success() {
346                bail!(
347                    "failed to fetch revision {} in directory '{}'",
348                    rev,
349                    directory.display()
350                );
351            }
352            bail!(
353                "failed to checkout revision {} in directory '{}': {}",
354                rev,
355                directory.display(),
356                String::from_utf8_lossy(&checkout_output.stderr)
357            );
358        }
359
360        Ok(())
361    }
362
363    fn install_rust_wasm_target_if_needed(&self) -> Result<()> {
364        let rustc_output = util::command::new_std_command("rustc")
365            .arg("--print")
366            .arg("sysroot")
367            .output()
368            .context("failed to run rustc")?;
369        if !rustc_output.status.success() {
370            bail!(
371                "failed to retrieve rust sysroot: {}",
372                String::from_utf8_lossy(&rustc_output.stderr)
373            );
374        }
375
376        let sysroot = PathBuf::from(String::from_utf8(rustc_output.stdout)?.trim());
377        if sysroot.join("lib/rustlib").join(RUST_TARGET).exists() {
378            return Ok(());
379        }
380
381        let output = util::command::new_std_command("rustup")
382            .args(["target", "add", RUST_TARGET])
383            .stderr(Stdio::piped())
384            .stdout(Stdio::inherit())
385            .output()
386            .context("failed to run `rustup target add`")?;
387        if !output.status.success() {
388            bail!(
389                "failed to install the `{RUST_TARGET}` target: {}",
390                String::from_utf8_lossy(&rustc_output.stderr)
391            );
392        }
393
394        Ok(())
395    }
396
397    async fn install_wasi_sdk_if_needed(&self) -> Result<PathBuf> {
398        let url = if let Some(asset_name) = WASI_SDK_ASSET_NAME {
399            format!("{WASI_SDK_URL}{asset_name}")
400        } else {
401            bail!("wasi-sdk is not available for platform {}", env::consts::OS);
402        };
403
404        let wasi_sdk_dir = self.cache_dir.join("wasi-sdk");
405        let mut clang_path = wasi_sdk_dir.clone();
406        clang_path.extend(["bin", &format!("clang{}", env::consts::EXE_SUFFIX)]);
407
408        if fs::metadata(&clang_path).map_or(false, |metadata| metadata.is_file()) {
409            return Ok(clang_path);
410        }
411
412        let mut tar_out_dir = wasi_sdk_dir.clone();
413        tar_out_dir.set_extension("archive");
414
415        fs::remove_dir_all(&wasi_sdk_dir).ok();
416        fs::remove_dir_all(&tar_out_dir).ok();
417
418        log::info!("downloading wasi-sdk to {}", wasi_sdk_dir.display());
419        let mut response = self.http.get(&url, AsyncBody::default(), true).await?;
420        let body = BufReader::new(response.body_mut());
421        let body = GzipDecoder::new(body);
422        let tar = Archive::new(body);
423
424        tar.unpack(&tar_out_dir)
425            .await
426            .context("failed to unpack wasi-sdk archive")?;
427
428        let inner_dir = fs::read_dir(&tar_out_dir)?
429            .next()
430            .context("no content")?
431            .context("failed to read contents of extracted wasi archive directory")?
432            .path();
433        fs::rename(&inner_dir, &wasi_sdk_dir).context("failed to move extracted wasi dir")?;
434        fs::remove_dir_all(&tar_out_dir).ok();
435
436        Ok(clang_path)
437    }
438
439    // This was adapted from:
440    // https://github.com/bytecodealliance/wasm-tools/blob/e8809bb17fcf69aa8c85cd5e6db7cff5cf36b1de/src/bin/wasm-tools/strip.rs
441    fn strip_custom_sections(&self, input: &Vec<u8>) -> Result<Vec<u8>> {
442        use wasmparser::Payload::*;
443
444        let strip_custom_section = |name: &str| {
445            // Default strip everything but:
446            // * the `name` section
447            // * any `component-type` sections
448            // * the `dylink.0` section
449            // * our custom version section
450            name != "name"
451                && !name.starts_with("component-type:")
452                && name != "dylink.0"
453                && name != "zed:api-version"
454        };
455
456        let mut output = Vec::new();
457        let mut stack = Vec::new();
458
459        for payload in Parser::new(0).parse_all(&input) {
460            let payload = payload?;
461
462            // Track nesting depth, so that we don't mess with inner producer sections:
463            match payload {
464                Version { encoding, .. } => {
465                    output.extend_from_slice(match encoding {
466                        wasmparser::Encoding::Component => &wasm_encoder::Component::HEADER,
467                        wasmparser::Encoding::Module => &wasm_encoder::Module::HEADER,
468                    });
469                }
470                ModuleSection { .. } | ComponentSection { .. } => {
471                    stack.push(mem::take(&mut output));
472                    continue;
473                }
474                End { .. } => {
475                    let mut parent = match stack.pop() {
476                        Some(c) => c,
477                        None => break,
478                    };
479                    if output.starts_with(&wasm_encoder::Component::HEADER) {
480                        parent.push(ComponentSectionId::Component as u8);
481                        output.encode(&mut parent);
482                    } else {
483                        parent.push(ComponentSectionId::CoreModule as u8);
484                        output.encode(&mut parent);
485                    }
486                    output = parent;
487                }
488                _ => {}
489            }
490
491            match &payload {
492                CustomSection(c) => {
493                    if strip_custom_section(c.name()) {
494                        continue;
495                    }
496                }
497
498                _ => {}
499            }
500            if let Some((id, range)) = payload.as_section() {
501                RawSection {
502                    id,
503                    data: &input[range],
504                }
505                .append_to(&mut output);
506            }
507        }
508
509        Ok(output)
510    }
511}
512
513fn populate_defaults(manifest: &mut ExtensionManifest, extension_path: &Path) -> Result<()> {
514    // For legacy extensions on the v0 schema (aka, using `extension.json`), clear out any existing
515    // contents of the computed fields, since we don't care what the existing values are.
516    if manifest.schema_version.is_v0() {
517        manifest.languages.clear();
518        manifest.grammars.clear();
519        manifest.themes.clear();
520    }
521
522    let cargo_toml_path = extension_path.join("Cargo.toml");
523    if cargo_toml_path.exists() {
524        manifest.lib.kind = Some(ExtensionLibraryKind::Rust);
525    }
526
527    let languages_dir = extension_path.join("languages");
528    if languages_dir.exists() {
529        for entry in fs::read_dir(&languages_dir).context("failed to list languages dir")? {
530            let entry = entry?;
531            let language_dir = entry.path();
532            let config_path = language_dir.join("config.toml");
533            if config_path.exists() {
534                let relative_language_dir =
535                    language_dir.strip_prefix(extension_path)?.to_path_buf();
536                if !manifest.languages.contains(&relative_language_dir) {
537                    manifest.languages.push(relative_language_dir);
538                }
539            }
540        }
541    }
542
543    let themes_dir = extension_path.join("themes");
544    if themes_dir.exists() {
545        for entry in fs::read_dir(&themes_dir).context("failed to list themes dir")? {
546            let entry = entry?;
547            let theme_path = entry.path();
548            if theme_path.extension() == Some("json".as_ref()) {
549                let relative_theme_path = theme_path.strip_prefix(extension_path)?.to_path_buf();
550                if !manifest.themes.contains(&relative_theme_path) {
551                    manifest.themes.push(relative_theme_path);
552                }
553            }
554        }
555    }
556
557    let icon_themes_dir = extension_path.join("icon_themes");
558    if icon_themes_dir.exists() {
559        for entry in fs::read_dir(&icon_themes_dir).context("failed to list icon themes dir")? {
560            let entry = entry?;
561            let icon_theme_path = entry.path();
562            if icon_theme_path.extension() == Some("json".as_ref()) {
563                let relative_icon_theme_path =
564                    icon_theme_path.strip_prefix(extension_path)?.to_path_buf();
565                if !manifest.icon_themes.contains(&relative_icon_theme_path) {
566                    manifest.icon_themes.push(relative_icon_theme_path);
567                }
568            }
569        }
570    }
571
572    let snippets_json_path = extension_path.join("snippets.json");
573    if snippets_json_path.exists() {
574        manifest.snippets = Some(snippets_json_path);
575    }
576
577    // For legacy extensions on the v0 schema (aka, using `extension.json`), we want to populate the grammars in
578    // the manifest using the contents of the `grammars` directory.
579    if manifest.schema_version.is_v0() {
580        let grammars_dir = extension_path.join("grammars");
581        if grammars_dir.exists() {
582            for entry in fs::read_dir(&grammars_dir).context("failed to list grammars dir")? {
583                let entry = entry?;
584                let grammar_path = entry.path();
585                if grammar_path.extension() == Some("toml".as_ref()) {
586                    #[derive(Deserialize)]
587                    struct GrammarConfigToml {
588                        pub repository: String,
589                        pub commit: String,
590                        #[serde(default)]
591                        pub path: Option<String>,
592                    }
593
594                    let grammar_config = fs::read_to_string(&grammar_path)?;
595                    let grammar_config: GrammarConfigToml = toml::from_str(&grammar_config)?;
596
597                    let grammar_name = grammar_path
598                        .file_stem()
599                        .and_then(|stem| stem.to_str())
600                        .context("no grammar name")?;
601                    if !manifest.grammars.contains_key(grammar_name) {
602                        manifest.grammars.insert(
603                            grammar_name.into(),
604                            GrammarManifestEntry {
605                                repository: grammar_config.repository,
606                                rev: grammar_config.commit,
607                                path: grammar_config.path,
608                            },
609                        );
610                    }
611                }
612            }
613        }
614    }
615
616    Ok(())
617}