Add an extensions API to the collaboration server (#7807)

This PR adds a REST API to the collab server for searching and
downloading extensions. Previously, we had implemented this API in
zed.dev directly, but this implementation is better, because we use the
collab database to store the download counts for extensions.

Release Notes:

- N/A

---------

Co-authored-by: Marshall Bowers <elliott.codes@gmail.com>
Co-authored-by: Marshall <marshall@zed.dev>
Co-authored-by: Conrad <conrad@zed.dev>

crates/collab/src/db/queries/extensions.rs

@@ -0,0 +1,205 @@
+use super::*;
+
+impl Database {
+    pub async fn get_extensions(
+        &self,
+        filter: Option<&str>,
+        limit: usize,
+    ) -> Result<Vec<ExtensionMetadata>> {
+        self.transaction(|tx| async move {
+            let mut condition = Condition::all();
+            if let Some(filter) = filter {
+                let fuzzy_name_filter = Self::fuzzy_like_string(filter);
+                condition = condition.add(Expr::cust_with_expr("name ILIKE $1", fuzzy_name_filter));
+            }
+
+            let extensions = extension::Entity::find()
+                .filter(condition)
+                .order_by_desc(extension::Column::TotalDownloadCount)
+                .order_by_asc(extension::Column::Id)
+                .limit(Some(limit as u64))
+                .filter(
+                    extension::Column::LatestVersion
+                        .into_expr()
+                        .eq(extension_version::Column::Version.into_expr()),
+                )
+                .inner_join(extension_version::Entity)
+                .select_also(extension_version::Entity)
+                .all(&*tx)
+                .await?;
+
+            Ok(extensions
+                .into_iter()
+                .filter_map(|(extension, latest_version)| {
+                    let version = latest_version?;
+                    Some(ExtensionMetadata {
+                        id: extension.external_id,
+                        name: extension.name,
+                        version: version.version,
+                        authors: version
+                            .authors
+                            .split(',')
+                            .map(|author| author.trim().to_string())
+                            .collect::<Vec<_>>(),
+                        repository: version.repository,
+                        published_at: version.published_at,
+                        download_count: extension.total_download_count as u64,
+                    })
+                })
+                .collect())
+        })
+        .await
+    }
+
+    pub async fn get_known_extension_versions<'a>(&self) -> Result<HashMap<String, Vec<String>>> {
+        self.transaction(|tx| async move {
+            let mut extension_external_ids_by_id = HashMap::default();
+
+            let mut rows = extension::Entity::find().stream(&*tx).await?;
+            while let Some(row) = rows.next().await {
+                let row = row?;
+                extension_external_ids_by_id.insert(row.id, row.external_id);
+            }
+            drop(rows);
+
+            let mut known_versions_by_extension_id: HashMap<String, Vec<String>> =
+                HashMap::default();
+            let mut rows = extension_version::Entity::find().stream(&*tx).await?;
+            while let Some(row) = rows.next().await {
+                let row = row?;
+
+                let Some(extension_id) = extension_external_ids_by_id.get(&row.extension_id) else {
+                    continue;
+                };
+
+                let versions = known_versions_by_extension_id
+                    .entry(extension_id.clone())
+                    .or_default();
+                if let Err(ix) = versions.binary_search(&row.version) {
+                    versions.insert(ix, row.version);
+                }
+            }
+            drop(rows);
+
+            Ok(known_versions_by_extension_id)
+        })
+        .await
+    }
+
+    pub async fn insert_extension_versions(
+        &self,
+        versions_by_extension_id: &HashMap<&str, Vec<NewExtensionVersion>>,
+    ) -> Result<()> {
+        self.transaction(|tx| async move {
+            for (external_id, versions) in versions_by_extension_id {
+                if versions.is_empty() {
+                    continue;
+                }
+
+                let latest_version = versions
+                    .iter()
+                    .max_by_key(|version| &version.version)
+                    .unwrap();
+
+                let insert = extension::Entity::insert(extension::ActiveModel {
+                    name: ActiveValue::Set(latest_version.name.clone()),
+                    external_id: ActiveValue::Set(external_id.to_string()),
+                    id: ActiveValue::NotSet,
+                    latest_version: ActiveValue::Set(latest_version.version.to_string()),
+                    total_download_count: ActiveValue::NotSet,
+                })
+                .on_conflict(
+                    OnConflict::columns([extension::Column::ExternalId])
+                        .update_column(extension::Column::ExternalId)
+                        .to_owned(),
+                );
+
+                let extension = if tx.support_returning() {
+                    insert.exec_with_returning(&*tx).await?
+                } else {
+                    // Sqlite
+                    insert.exec_without_returning(&*tx).await?;
+                    extension::Entity::find()
+                        .filter(extension::Column::ExternalId.eq(*external_id))
+                        .one(&*tx)
+                        .await?
+                        .ok_or_else(|| anyhow!("failed to insert extension"))?
+                };
+
+                extension_version::Entity::insert_many(versions.iter().map(|version| {
+                    extension_version::ActiveModel {
+                        extension_id: ActiveValue::Set(extension.id),
+                        published_at: ActiveValue::Set(version.published_at),
+                        version: ActiveValue::Set(version.version.to_string()),
+                        authors: ActiveValue::Set(version.authors.join(", ")),
+                        repository: ActiveValue::Set(version.repository.clone()),
+                        description: ActiveValue::Set(version.description.clone()),
+                        download_count: ActiveValue::NotSet,
+                    }
+                }))
+                .on_conflict(OnConflict::new().do_nothing().to_owned())
+                .exec_without_returning(&*tx)
+                .await?;
+
+                if let Ok(db_version) = semver::Version::parse(&extension.latest_version) {
+                    if db_version >= latest_version.version {
+                        continue;
+                    }
+                }
+
+                let mut extension = extension.into_active_model();
+                extension.latest_version = ActiveValue::Set(latest_version.version.to_string());
+                extension.name = ActiveValue::set(latest_version.name.clone());
+                extension::Entity::update(extension).exec(&*tx).await?;
+            }
+
+            Ok(())
+        })
+        .await
+    }
+
+    pub async fn record_extension_download(&self, extension: &str, version: &str) -> Result<bool> {
+        self.transaction(|tx| async move {
+            #[derive(Copy, Clone, Debug, EnumIter, DeriveColumn)]
+            enum QueryId {
+                Id,
+            }
+
+            let extension_id: Option<ExtensionId> = extension::Entity::find()
+                .filter(extension::Column::ExternalId.eq(extension))
+                .select_only()
+                .column(extension::Column::Id)
+                .into_values::<_, QueryId>()
+                .one(&*tx)
+                .await?;
+            let Some(extension_id) = extension_id else {
+                return Ok(false);
+            };
+
+            extension_version::Entity::update_many()
+                .col_expr(
+                    extension_version::Column::DownloadCount,
+                    extension_version::Column::DownloadCount.into_expr().add(1),
+                )
+                .filter(
+                    extension_version::Column::ExtensionId
+                        .eq(extension_id)
+                        .and(extension_version::Column::Version.eq(version)),
+                )
+                .exec(&*tx)
+                .await?;
+
+            extension::Entity::update_many()
+                .col_expr(
+                    extension::Column::TotalDownloadCount,
+                    extension::Column::TotalDownloadCount.into_expr().add(1),
+                )
+                .filter(extension::Column::Id.eq(extension_id))
+                .exec(&*tx)
+                .await?;
+
+            Ok(true)
+        })
+        .await
+    }
+}