Add _catalog endpoints for listing repositories

src/api/catalog.rs

@@ -0,0 +1,66 @@
+use actix_web::{HttpResponse, web, get, HttpRequest};
+use qstring::QString;
+use serde::{Serialize, Deserialize};
+
+use crate::{app_state::AppState, database::Database};
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct RepositoryList {
+    repositories: Vec<String>,
+}
+
+#[get("")]
+pub async fn list_repositories(req: HttpRequest, state: web::Data<AppState>) -> HttpResponse {
+    // Get limit and last tag from query params if present.
+    let qs = QString::from(req.query_string());
+    let limit = qs.get("n");
+    let last_repo = qs.get("last");
+
+    let mut link_header = None;
+
+    // Paginate tag results if n was specified, else just pull everything.
+    let database = &state.database;
+    let repositories = match limit {
+        Some(limit) => {
+            let limit: u32 = limit.parse().unwrap();
+
+            // Convert the last param to a String, and list all the repos
+            let last_repo = last_repo.and_then(|t| Some(t.to_string()));
+            let repos = database.list_repositories(Some(limit), last_repo).await.unwrap();
+
+            // Get the new last repository for the response
+            let last_repo = repos.last().and_then(|s| Some(s.clone()));
+
+            // Construct the link header
+            let url = req.uri().to_string();
+            let mut url = format!("<{}/v2/_catalog?n={}", url, limit);
+            if let Some(last_repo) = last_repo {
+                url += &format!("&limit={}", last_repo);
+            }
+            url += ">; rel=\"next\"";
+            link_header = Some(url);
+
+            repos
+        },
+        None => {
+            database.list_repositories(None, None).await.unwrap()
+        }
+    };
+
+    // Convert the `Vec<Tag>` to a `TagList` which will be serialized to json.
+    let repo_list = RepositoryList {
+        repositories,
+    };
+    let response_body = serde_json::to_string(&repo_list).unwrap();
+    
+    // Construct the response, optionally adding the Link header if it was constructed.
+    let mut resp = HttpResponse::Ok();
+    resp.append_header(("Content-Type", "application/json"));
+
+    if let Some(link_header) = link_header {
+        resp.append_header(("Link", link_header));
+    }
+        
+    resp.body(response_body)
+}

src/api/mod.rs

@@ -2,6 +2,7 @@ pub mod blobs;
 pub mod uploads;
 pub mod manifests;
 pub mod tags;
+pub mod catalog;
 
 use actix_web::{HttpResponse, get};
 

src/api/tags.rs

@@ -28,20 +28,25 @@ pub async fn list_tags(path: web::Path<(String, )>, req: HttpRequest, state: web
         Some(limit) => {
             let limit: u32 = limit.parse().unwrap();
 
+            // Convert the last param to a String, and list all the tags
             let last_tag = last_tag.and_then(|t| Some(t.to_string()));
+            let tags = database.list_repository_tags_page(&name, limit, last_tag).await.unwrap();
+
+            // Get the new last repository for the response
+            let last_tag = tags.last();
 
             // Construct the link header
-            let mut url = format!("/v2/{}/tags/list?n={}", name, limit);
-            if let Some(last_tag) = last_tag.clone() {
-                url += &format!("&limit={}", last_tag);
+            let url = req.uri().to_string();
+            let mut url = format!("<{}/v2/{}/tags/list?n={}", url, name, limit);
+            if let Some(last_tag) = last_tag {
+                url += &format!("&limit={}", last_tag.name);
             }
-            url += ";rel=\"next\"";
+            url += ">; rel=\"next\"";
             link_header = Some(url);
 
-            database.list_repository_tags_page(&name, limit, last_tag).await.unwrap()
+            tags
         },
         None => {
-            let database = &state.database;
             database.list_repository_tags(&name).await.unwrap()
         }
     };

src/database/mod.rs

@@ -54,8 +54,9 @@ pub trait Database {
 
     /// Create a repository
     async fn save_repository(&self, repository: &str) -> sqlx::Result<()>;
-    /// List all repositories
-    async fn list_repositories(&self) -> sqlx::Result<Vec<String>>;
+    /// List all repositories. 
+    /// If limit is not specified, a default limit of 1000 will be returned.
+    async fn list_repositories(&self, limit: Option<u32>, last_repo: Option<String>) -> sqlx::Result<Vec<String>>;
 }
 
 #[async_trait]
@@ -285,11 +286,27 @@ impl Database for Pool<Sqlite> {
         Ok(())
     }
 
-    async fn list_repositories(&self) -> sqlx::Result<Vec<String>> {
-        let repos: Vec<(String, )> = sqlx::query_as("SELECT name FROM repositories")
-            .fetch_all(self).await?;
-        // Move out of repos
-        let repos = repos.into_iter().map(|row| row.0).collect();
+    //async fn list_repositories(&self) -> sqlx::Result<Vec<String>> {
+    async fn list_repositories(&self, limit: Option<u32>, last_repo: Option<String>) -> sqlx::Result<Vec<String>> {
+        let limit = limit.unwrap_or(1000); // set default limit
+
+        // Query differently depending on if `last_repo` was specified
+        let rows: Vec<(String, )> = match last_repo {
+            Some(last_repo) => {
+                sqlx::query_as("SELECT name FROM repositories WHERE name > ? ORDER BY name LIMIT ?")
+                    .bind(last_repo)
+                    .bind(limit)
+                    .fetch_all(self).await?
+            },
+            None => {
+                sqlx::query_as("SELECT name FROM repositories ORDER BY name LIMIT ?")
+                    .bind(limit)
+                    .fetch_all(self).await?
+            }
+        };
+
+        // "unwrap" the tuple from the rows
+        let repos: Vec<String> = rows.into_iter().map(|row| row.0).collect();
 
         Ok(repos)
     }

src/main.rs

@@ -40,6 +40,10 @@ async fn main() -> std::io::Result<()> {
             .service(
                 web::scope("/v2")
                     .service(api::version_check)
+                    .service(
+                        web::scope("/_catalog")
+                            .service(api::catalog::list_repositories)
+                    )
                     .service(
                         web::scope("/{name}")
                             .service(