feat(lsp): npm specifier completions (#20121)

1 files changed, 136 insertions, 0 deletions

diff --git a/cli/lsp/npm.rs b/cli/lsp/npm.rs
new file mode 100644
index 000000000..0f2794e44
--- /dev/null
+++ b/cli/lsp/npm.rs
@@ -0,0 +1,136 @@
+// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.
+
+use std::collections::HashMap;
+use std::sync::Arc;
+
+use deno_core::anyhow::anyhow;
+use deno_core::error::AnyError;
+use deno_core::parking_lot::Mutex;
+use deno_core::serde_json;
+use deno_core::url::Url;
+use deno_npm::registry::NpmPackageInfo;
+use deno_runtime::permissions::PermissionsContainer;
+use serde::Deserialize;
+
+use crate::file_fetcher::FileFetcher;
+use crate::npm::CliNpmRegistryApi;
+
+#[async_trait::async_trait]
+pub trait NpmSearchApi {
+  async fn search(&self, query: &str) -> Result<Arc<Vec<String>>, AnyError>;
+  async fn package_info(
+    &self,
+    name: &str,
+  ) -> Result<Arc<NpmPackageInfo>, AnyError>;
+}
+
+#[derive(Debug, Clone)]
+pub struct CliNpmSearchApi {
+  base_url: Url,
+  file_fetcher: FileFetcher,
+  info_cache: Arc<Mutex<HashMap<String, Arc<NpmPackageInfo>>>>,
+  search_cache: Arc<Mutex<HashMap<String, Arc<Vec<String>>>>>,
+}
+
+impl CliNpmSearchApi {
+  pub fn new(file_fetcher: FileFetcher, custom_base_url: Option<Url>) -> Self {
+    Self {
+      base_url: custom_base_url
+        .unwrap_or_else(|| CliNpmRegistryApi::default_url().clone()),
+      file_fetcher,
+      info_cache: Default::default(),
+      search_cache: Default::default(),
+    }
+  }
+}
+
+#[async_trait::async_trait]
+impl NpmSearchApi for CliNpmSearchApi {
+  async fn search(&self, query: &str) -> Result<Arc<Vec<String>>, AnyError> {
+    if let Some(names) = self.search_cache.lock().get(query) {
+      return Ok(names.clone());
+    }
+    let mut search_url = self.base_url.clone();
+    search_url
+      .path_segments_mut()
+      .map_err(|_| anyhow!("Custom npm registry URL cannot be a base."))?
+      .pop_if_empty()
+      .extend("-/v1/search".split('/'));
+    search_url
+      .query_pairs_mut()
+      .append_pair("text", &format!("{} boost-exact:false", query));
+    let file = self
+      .file_fetcher
+      .fetch(&search_url, PermissionsContainer::allow_all())
+      .await?;
+    let names = Arc::new(parse_npm_search_response(&file.source)?);
+    self
+      .search_cache
+      .lock()
+      .insert(query.to_string(), names.clone());
+    Ok(names)
+  }
+
+  async fn package_info(
+    &self,
+    name: &str,
+  ) -> Result<Arc<NpmPackageInfo>, AnyError> {
+    if let Some(info) = self.info_cache.lock().get(name) {
+      return Ok(info.clone());
+    }
+    let mut info_url = self.base_url.clone();
+    info_url
+      .path_segments_mut()
+      .map_err(|_| anyhow!("Custom npm registry URL cannot be a base."))?
+      .pop_if_empty()
+      .push(name);
+    let file = self
+      .file_fetcher
+      .fetch(&info_url, PermissionsContainer::allow_all())
+      .await?;
+    let info = Arc::new(serde_json::from_str::<NpmPackageInfo>(&file.source)?);
+    self
+      .info_cache
+      .lock()
+      .insert(name.to_string(), info.clone());
+    Ok(info)
+  }
+}
+
+fn parse_npm_search_response(source: &str) -> Result<Vec<String>, AnyError> {
+  #[derive(Debug, Deserialize)]
+  struct Package {
+    name: String,
+  }
+  #[derive(Debug, Deserialize)]
+  struct Object {
+    package: Package,
+  }
+  #[derive(Debug, Deserialize)]
+  struct Response {
+    objects: Vec<Object>,
+  }
+  let objects = serde_json::from_str::<Response>(source)?.objects;
+  Ok(objects.into_iter().map(|o| o.package.name).collect())
+}
+
+#[cfg(test)]
+mod tests {
+  use super::*;
+
+  #[test]
+  fn test_parse_npm_search_response() {
+    // This is a subset of a realistic response only containing data currently
+    // used by our parser. It's enough to catch regressions.
+    let names = parse_npm_search_response(r#"{"objects":[{"package":{"name":"puppeteer"}},{"package":{"name":"puppeteer-core"}},{"package":{"name":"puppeteer-extra-plugin-stealth"}},{"package":{"name":"puppeteer-extra-plugin"}}]}"#).unwrap();
+    assert_eq!(
+      names,
+      vec![
+        "puppeteer".to_string(),
+        "puppeteer-core".to_string(),
+        "puppeteer-extra-plugin-stealth".to_string(),
+        "puppeteer-extra-plugin".to_string()
+      ]
+    );
+  }
+}