initialize remote data in one go

Previously each extension was fetched separately from the API, this
fetches all installed ones in one go, speeding up the first open on cold
cache significantly.

lib/plugins/extension/GuiAdmin.php

@@ -64,6 +64,12 @@ class GuiAdmin extends Gui
         $html .= '</div>';
 
         $plugins = (new Local())->getPlugins();
+        try {
+            // initialize remote data in one go
+            Repository::getInstance()->initExtensions(array_keys($plugins));
+        } catch (Exception $e) {
+            msg($e->getMessage(), -1); // this should not happen
+        }
 
         $html .= '<div id="extension__list">';
         $html .= '<form action="' . $this->tabURL('plugins') . '" method="post">';
@@ -91,6 +97,12 @@ class GuiAdmin extends Gui
         $html .= '</div>';
 
         $templates = (new Local())->getTemplates();
+        try {
+            // initialize remote data in one go
+            Repository::getInstance()->initExtensions(array_keys($templates));
+        } catch (Exception $e) {
+            msg($e->getMessage(), -1); // this should not happen
+        }
 
         $html .= '<div id="extension__list">';
         $html .= '<form action="' . $this->tabURL('templates') . '" method="post">';

lib/plugins/extension/Repository.php

@@ -135,7 +135,7 @@ class Repository
         // first get all that are cached
         foreach ($ids as $id) {
             $data = $this->retrieveCache($id);
-            if ($data === null) {
+            if ($data === null || $data === []) {
                 $toload[] = $id;
             } else {
                 $result[$id] = Extension::createFromRemoteData($data);
@@ -147,7 +147,7 @@ class Repository
             $this->fetchExtensions($toload);
             foreach ($toload as $id) {
                 $data = $this->retrieveCache($id);
-                if ($data === null) {
+                if ($data === null || $data === []) {
                     $result[$id] = null;
                 } else {
                     $result[$id] = Extension::createFromRemoteData($data);

lib/plugins/extension/cli.php

@@ -258,7 +258,11 @@ class cli_plugin_extension extends CLIPlugin
      */
     protected function cmdList($showdetails, $filter)
     {
-        $this->listExtensions((new Local())->getExtensions(), $showdetails, $filter);
+        $extensions = (new Local())->getExtensions();
+        // initialize remote data in one go
+        Repository::getInstance()->initExtensions(array_keys($extensions));
+
+        $this->listExtensions($extensions, $showdetails, $filter);
         return 0;
     }