feat(cosmic-swingset): export swingStore kvData to vstorage

golang/cosmos/x/swingset/keeper/keeper.go

@@ -32,6 +32,7 @@ const (
 	StoragePathMailbox      = "mailbox"
 	StoragePathCustom       = "published"
 	StoragePathBundles      = "bundles"
+	StoragePathSwingStore   = "swingStore"
 )
 
 // 2 ** 256 - 1

packages/cosmic-swingset/src/chain-main.js

@@ -14,7 +14,7 @@ import {
   exportMailbox,
 } from '@agoric/swingset-vat/src/devices/mailbox/mailbox.js';
 
-import { Fail } from '@agoric/assert';
+import { Fail, q } from '@agoric/assert';
 import { makeSlogSender, tryFlushSlogSender } from '@agoric/telemetry';
 
 import {
@@ -243,6 +243,42 @@ export default async function main(progname, args, { env, homedir, agcc }) {
       commit: actionQueueRawStorage.commit,
       abort: actionQueueRawStorage.abort,
     });
+    /**
+     * Callback invoked during SwingSet execution when new "export data" is
+     * generated by swingStore to be saved in the host's verified DB. In our
+     * case, we publish these entries in vstorage under a dedicated prefix.
+     * This effectively shadows the "export data" of the swingStore so that
+     * processes like state-sync can generate a verified "root of trust" to
+     * restore SwingSet state.
+     *
+     * @param {ReadonlyArray<[path: string, value?: string | null]>} updates
+     */
+    const swingStoreExportCallback = async updates => {
+      // Allow I/O to proceed first
+      await waitUntilQuiescent();
+
+      const entries = updates.map(([key, value]) => {
+        if (typeof key !== 'string') {
+          throw Fail`Unexpected swingStore exported key ${q(key)}`;
+        }
+        const path = `${STORAGE_PATH.SWING_STORE}.${key}`;
+        if (value == null) {
+          return [path];
+        }
+        if (typeof value !== 'string') {
+          throw Fail`Unexpected ${typeof value} value for swingStore exported key ${q(
+            key,
+          )}`;
+        }
+        return [path, value];
+      });
+      sendToChain(
+        stringify({
+          method: 'setWithoutNotify',
+          args: entries,
+        }),
+      );
+    };
     function setActivityhash(activityhash) {
       const entry = [STORAGE_PATH.ACTIVITYHASH, activityhash];
       const msg = stringify({
@@ -399,6 +435,7 @@ export default async function main(progname, args, { env, homedir, agcc }) {
       verboseBlocks: true,
       metricsProvider,
       slogSender,
+      swingStoreExportCallback,
       swingStoreTraceFile,
       keepSnapshots,
       afterCommitCallback,

packages/cosmic-swingset/src/launch-chain.js

@@ -19,6 +19,7 @@ import { waitUntilQuiescent } from '@agoric/swingset-vat/src/lib-nodejs/waitUnti
 import { assert, Fail } from '@agoric/assert';
 import { openSwingStore } from '@agoric/swing-store';
 import { BridgeId as BRIDGE_ID } from '@agoric/internal';
+import { makeWithQueue } from '@agoric/internal/src/queue.js';
 import * as ActionType from '@agoric/internal/src/action-types.js';
 
 import { extractCoreProposalBundles } from '@agoric/deploy-script-support/src/extract-proposal.js';
@@ -226,13 +227,28 @@ export async function launch({
   metricsProvider = makeDefaultMeterProvider(),
   slogSender,
   swingStoreTraceFile,
+  swingStoreExportCallback,
   keepSnapshots,
   afterCommitCallback = async () => ({}),
 }) {
   console.info('Launching SwingSet kernel');
 
+  // The swingStore's exportCallback is synchronous, however we allow the
+  // callback provided to launch-chain to be asynchronous. The callbacks are
+  // invoked sequentially like if they were awaited, and the block manager
+  // synchronizes before finishing END_BLOCK
+  let pendingSwingStoreExport = Promise.resolve();
+  const swingStoreExportCallbackWithQueue =
+    swingStoreExportCallback && makeWithQueue()(swingStoreExportCallback);
+  const swingStoreExportSyncCallback =
+    swingStoreExportCallback &&
+    (updates => {
+      pendingSwingStoreExport = swingStoreExportCallbackWithQueue(updates);
+    });
+
   const { kernelStorage, hostStorage } = openSwingStore(kernelStateDBDir, {
     traceFile: swingStoreTraceFile,
+    exportCallback: swingStoreExportSyncCallback,
     keepSnapshots,
   });
   const { kvStore, commit } = hostStorage;
@@ -647,6 +663,7 @@ export async function launch({
           blockHeight,
           runNum,
         });
+        await pendingSwingStoreExport;
         controller.writeSlogObject({
           type: 'cosmic-swingset-bootstrap-block-finish',
           blockTime,
@@ -758,7 +775,7 @@ export async function launch({
 
           // We write out our on-chain state as a number of chainSends.
           const start = Date.now();
-          await saveChainState();
+          await Promise.all([saveChainState(), pendingSwingStoreExport]);
           chainTime = Date.now() - start;
 
           // Advance our saved state variables.

packages/internal/src/chain-storage-paths.js

@@ -11,3 +11,4 @@ export const EGRESS = 'egress';
 export const MAILBOX = 'mailbox';
 export const BUNDLES = 'bundles';
 export const CUSTOM = 'published';
+export const SWING_STORE = 'swingStore';