Cache mirror list

src/versionManager.ts

@@ -36,7 +36,7 @@ export interface Config {
      * `"version"` for Zig, `"--version"` for ZLS
      */
     versionArg: string;
-    mirrorUrls: vscode.Uri[];
+    getMirrorUrls: () => Promise<vscode.Uri[]>;
     canonicalUrl: {
         release: vscode.Uri;
         nightly: vscode.Uri;
@@ -93,7 +93,7 @@ async function installGuarded(config: Config, version: semver.SemVer): Promise<s
         throw new Error(`Can't install ${config.title} because 'tar' could not be found`);
     }
 
-    const mirrors = [...config.mirrorUrls]
+    const mirrors = [...(await config.getMirrorUrls())]
         .map((mirror) => ({ mirror, sort: Math.random() }))
         .sort((a, b) => a.sort - b.sort)
         .map(({ mirror }) => mirror);

src/zigSetup.ts

@@ -577,6 +577,33 @@ async function updateStatus(context: vscode.ExtensionContext): Promise<void> {
         });
 }
 
+async function getMirrors(context: vscode.ExtensionContext): Promise<vscode.Uri[]> {
+    const key = "zig-mirror-cache";
+    let cached = context.globalState.get(key, { timestamp: 0, mirrors: "" });
+
+    const millisecondsInDay = 24 * 60 * 60 * 1000;
+    if (new Date().getTime() - cached.timestamp > millisecondsInDay) {
+        try {
+            const response = await fetch("https://ziglang.org/download/community-mirrors.txt");
+            if (response.status !== 200) throw Error("invalid mirrors");
+            const mirrorList = await response.text();
+            cached = {
+                timestamp: new Date().getTime(),
+                mirrors: mirrorList,
+            };
+            context.globalState.update(key, cached);
+        } catch {
+            // Cannot fetch mirrors, rely on cache.
+        }
+    }
+
+    return cached.mirrors
+        .trim()
+        .split("\n")
+        .filter((u) => !!u)
+        .map((u) => vscode.Uri.parse(u));
+}
+
 export async function setupZig(context: vscode.ExtensionContext) {
     {
         // This check can be removed once enough time has passed so that most users switched to the new value
@@ -674,19 +701,6 @@ export async function setupZig(context: vscode.ExtensionContext) {
             break;
     }
 
-    let mirrors: vscode.Uri[] = [];
-    try {
-        const response = await fetch("https://ziglang.org/download/community-mirrors.txt");
-        if (response.status !== 200) throw Error("invalid mirrors");
-        const mirrorList = await response.text();
-        mirrors = mirrorList
-            .trim()
-            .split("\n")
-            .map((u) => vscode.Uri.parse(u));
-    } catch {
-        // Cannot fetch mirrors, attempt downloading from canonical source.
-    }
-
     versionManagerConfig = {
         context: context,
         title: "Zig",
@@ -695,7 +709,9 @@ export async function setupZig(context: vscode.ExtensionContext) {
         /** https://ziglang.org/download */
         minisignKey: minisign.parseKey("RWSGOq2NVecA2UPNdBUZykf1CCb147pkmdtYxgb3Ti+JO/wCYvhbAb/U"),
         versionArg: "version",
-        mirrorUrls: mirrors,
+        getMirrorUrls() {
+            return getMirrors(context);
+        },
         canonicalUrl: {
             release: vscode.Uri.parse("https://ziglang.org/download"),
             nightly: vscode.Uri.parse("https://ziglang.org/builds"),

src/zls.ts

@@ -511,7 +511,9 @@ export async function activate(context: vscode.ExtensionContext) {
         /** https://github.com/zigtools/release-worker */
         minisignKey: minisign.parseKey("RWR+9B91GBZ0zOjh6Lr17+zKf5BoSuFvrx2xSeDE57uIYvnKBGmMjOex"),
         versionArg: "--version",
-        mirrorUrls: [],
+        getMirrorUrls() {
+            return Promise.resolve([]);
+        },
         canonicalUrl: {
             release: vscode.Uri.parse("https://builds.zigtools.org"),
             nightly: vscode.Uri.parse("https://builds.zigtools.org"),