feat: allow resetting RocksDB cache

flake.lock

@@ -154,11 +154,11 @@
         "logos-module-builder": "logos-module-builder_4"
       },
       "locked": {
-        "lastModified": 1782982957,
-        "narHash": "sha256-L1W94vlMtKK5w6S9np2qFEY8tJ5M5g6Aryfrb3Bf4lo=",
+        "lastModified": 1782991756,
+        "narHash": "sha256-MhRCtwOctGTZ2+CMF93AAPV6nIO/X2uO4qcTxzLsgbw=",
         "ref": "erhant/bump-lez-and-fix-logging",
-        "rev": "69dbf45a57f94345d46ceca3c9bc563ce5fab0ae",
-        "revCount": 59,
+        "rev": "b2fde3c000d00c04da374b2c31719e29a237b2a4",
+        "revCount": 62,
         "type": "git",
         "url": "https://github.com/logos-blockchain/lez-indexer-module"
       },

src/lez_explorer_ui.rep

@@ -33,6 +33,11 @@ class LezExplorerUi
     // refresh the feed. The backend writes the JSON to a file itself — the UI
     // never deals with paths. Returns true on success.
     SLOT(bool applyConfigJson(QString json))
+    // Delete the indexer's RocksDB cache and restart from the saved config: the
+    // recovery path when the local store is stale against a different/reset chain
+    // (otherwise the indexer can sit at "caught up" on a mismatched store).
+    // Returns true on success.
+    SLOT(bool resetIndexerCache())
     // Reload the latest page into recentBlocks and re-baseline the poller.
     SLOT(void refreshBlocks())
     // Append the next older page of blocks to recentBlocks.

src/lez_explorer_ui_backend.cpp

@@ -399,6 +399,24 @@ bool LezExplorerUiBackend::applyConfigJson(QString json) {
     return ok;
 }
 
+bool LezExplorerUiBackend::resetIndexerCache() {
+    // reset_storage stops the indexer and deletes its RocksDB store; then we
+    // restart from the saved config so it re-indexes the current chain from
+    // scratch. The recovery path for a store left stale against a reset chain.
+    const qlonglong code = modules().lez_indexer_module.reset_storage(configFilePath());
+    if (code != 0) {
+        emit error(QStringLiteral("Failed to delete the indexer cache (code %1).").arg(code));
+        return false;
+    }
+
+    // Store is empty now; re-baseline the poller and restart ingestion.
+    m_lastPolledTip = 0;
+    m_polledOnce = false;
+    const bool ok = startIndexerFromFile();
+    refreshBlocks();
+    return ok;
+}
+
 void LezExplorerUiBackend::refreshBlocks() {
     const QString json = modules().lez_indexer_module.getBlocks(QString(), QStringLiteral("10"));
     m_recentBlocks = parseBlockArrayJson(json);

src/lez_explorer_ui_backend.h

@@ -40,6 +40,7 @@ public:
 
     // .rep SLOTs.
     bool applyConfigJson(QString json) override;
+    bool resetIndexerCache() override;
     void refreshBlocks() override;
     void loadMoreBlocks() override;
     QVariantMap getBlockById(QString id) override;

src/qml/pages/SettingsPage.qml

@@ -11,6 +11,8 @@ Item {
     property var explorer
     readonly property var backend: explorer ? explorer.backend : null
     property bool statusIsError: false
+    // Armed by the first "Delete Cache" tap; a second tap actually wipes.
+    property bool confirmingReset: false
 
     Component.onCompleted: {
         // Seed the editor with the saved config, falling back to the template.
@@ -83,6 +85,25 @@ Item {
                 font.pixelSize: Theme.typography.secondaryText
             }
 
+            // Delete the indexer's RocksDB cache and re-sync (two-tap confirm).
+            Rectangle {
+                Layout.preferredHeight: 38
+                Layout.preferredWidth: 150
+                radius: Theme.spacing.radiusMedium
+                color: resetCacheHover.hovered ? Qt.lighter(Theme.palette.error, 1.1) : Theme.palette.error
+
+                HoverHandler { id: resetCacheHover }
+                TapHandler { onTapped: page.resetCache() }
+
+                LogosText {
+                    anchors.centerIn: parent
+                    text: page.confirmingReset ? "Confirm delete" : "Delete Cache"
+                    color: Theme.palette.background
+                    font.pixelSize: Theme.typography.secondaryText
+                    font.weight: Theme.typography.weightBold
+                }
+            }
+
             // Reset to the built-in template.
             Rectangle {
                 Layout.preferredHeight: 38
@@ -93,7 +114,7 @@ Item {
                 border.color: Theme.palette.borderSecondary
 
                 HoverHandler { id: resetHover }
-                TapHandler { onTapped: if (page.backend) { editor.text = page.backend.defaultConfig; page.setStatus("", false); } }
+                TapHandler { onTapped: if (page.backend) { page.confirmingReset = false; editor.text = page.backend.defaultConfig; page.setStatus("", false); } }
 
                 LogosText {
                     anchors.centerIn: parent
@@ -129,9 +150,36 @@ Item {
         statusLabel.text = message;
     }
 
+    // Delete the indexer's RocksDB cache and re-sync. First tap arms; a second
+    // tap confirms (it's destructive — wipes the local index).
+    function resetCache() {
+        if (!page.backend)
+            return;
+        if (!page.confirmingReset) {
+            page.confirmingReset = true;
+            page.setStatus("Click “Confirm delete” to wipe the local index and re-sync from scratch.", true);
+            return;
+        }
+        page.confirmingReset = false;
+        page.setStatus("Deleting cache…", false);
+        logos.watch(page.backend.resetIndexerCache(),
+            function (ok) {
+                if (ok) {
+                    page.setStatus("Cache deleted. Indexer restarting…", false);
+                    page.explorer.goHome();
+                }
+                // On failure the backend emits error() (shown by onError above).
+            },
+            function (err) {
+                page.setStatus("Error: " + err, true);
+            });
+    }
+
     function save() {
         if (!page.backend)
             return;
+        // A save cancels a pending cache-delete confirmation.
+        page.confirmingReset = false;
         // Validate locally first for an immediate, precise error.
         try {
             JSON.parse(editor.text);