feat(telemetry): use makeSlogSenderFromModule

docs/env.md

@@ -115,6 +115,12 @@ Same as SLOGFILE, but for solo instead of chain.
 
 Lifetime: ?
 
+## SOLO_SLOGSENDER
+
+Same as SLOGSENDER, but for solo instead of chain.
+
+Lifetime: ?
+
 ## SOLO_MAX_DEBUG_LENGTH
 
 Affects: solo
@@ -137,6 +143,21 @@ debug logs should be written.
 
 Lifetime: ?
 
+## SLOGSENDER
+
+Affects: cosmic-swingset
+
+Purpose: intercept the SwingSet LOG file in realtime
+
+Description: when nonempty, use the value as a module specifier.  The module
+will be loaded by `@agoric/telemetry/src/make-slog-sender.js`, via
+`import(moduleSpec)`, and then the exported `makeSlogSender` function creates a
+`slogSender`.  Then, every time a SLOG object is written by SwingSet,
+`slogSender(slogObject)` will be called.
+
+The default is `'@agoric/telemetry/src/flight-recorder.js'`, which writes to an
+mmap'ed circular buffer.
+
 ## SWINGSET_WORKER_TYPE
 
 Affects: solo

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

@@ -7,6 +7,7 @@ import {
 } from '@agoric/swingset-vat/src/devices/mailbox.js';
 
 import { assert, details as X } from '@agoric/assert';
+import { makeSlogSenderFromModule } from '@agoric/telemetry';
 
 import { launch } from './launch-chain.js';
 import makeBlockManager from './block-manager.js';
@@ -249,7 +250,12 @@ export default async function main(progname, args, { env, homedir, agcc }) {
       ),
     ).pathname;
     const { metricsProvider } = getTelemetryProviders({ console, env });
-    const slogFile = env.SLOGFILE;
+
+    const { SLOGFILE, SLOGSENDER } = env;
+    const slogSender = await makeSlogSenderFromModule(SLOGSENDER, {
+      stateDir: stateDBDir,
+    });
+
     const consensusMode = env.DEBUG === undefined;
     const s = await launch(
       stateDBDir,
@@ -260,7 +266,8 @@ export default async function main(progname, args, { env, homedir, agcc }) {
       argv,
       undefined,
       metricsProvider,
-      slogFile,
+      SLOGFILE,
+      slogSender,
       consensusMode,
     );
     return s;

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

@@ -35,7 +35,7 @@ async function buildSwingset(
   hostStorage,
   vatconfig,
   argv,
-  { consensusMode, debugName = undefined, slogCallbacks, slogFile },
+  { consensusMode, debugName = undefined, slogCallbacks, slogFile, slogSender },
 ) {
   const debugPrefix = debugName === undefined ? '' : `${debugName}:`;
   let config = await loadSwingsetConfigFile(vatconfig);
@@ -78,7 +78,12 @@ async function buildSwingset(
   const controller = await makeSwingsetController(
     hostStorage,
     deviceEndowments,
-    { overrideVatManagerOptions: { consensusMode }, slogCallbacks, slogFile },
+    {
+      overrideVatManagerOptions: { consensusMode },
+      slogCallbacks,
+      slogFile,
+      slogSender,
+    },
   );
 
   // We DON'T want to run the kernel yet, only when the application decides
@@ -140,6 +145,7 @@ export async function launch(
   debugName = undefined,
   meterProvider = DEFAULT_METER_PROVIDER,
   slogFile = undefined,
+  slogSender,
   consensusMode = false,
 ) {
   console.info('Launching SwingSet kernel');
@@ -172,6 +178,7 @@ export async function launch(
       debugName,
       slogCallbacks,
       slogFile,
+      slogSender,
       consensusMode,
     },
   );

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

@@ -10,6 +10,8 @@ import {
 
 import anylogger from 'anylogger';
 
+import { makeSlogSenderFromModule } from '@agoric/telemetry';
+
 import { resolve as importMetaResolve } from 'import-meta-resolve';
 import { assert, details as X } from '@agoric/assert';
 import { makeWithQueue } from '@agoric/vats/src/queue.js';
@@ -83,6 +85,12 @@ export async function connectToFakeChain(basedir, GCI, delay, inbound) {
     console,
     env: process.env,
   });
+
+  const { SLOGFILE, SLOGSENDER } = process.env;
+  const slogSender = await makeSlogSenderFromModule(SLOGSENDER, {
+    stateDir: stateDBdir,
+  });
+
   const s = await launch(
     stateDBdir,
     mailboxStorage,
@@ -92,6 +100,8 @@ export async function connectToFakeChain(basedir, GCI, delay, inbound) {
     argv,
     GCI, // debugName
     metricsProvider,
+    SLOGFILE,
+    slogSender,
   );
 
   const { savedHeight, savedActions, savedChainSends } = s;

packages/solo/package.json

@@ -24,6 +24,7 @@
   "dependencies": {
     "@agoric/access-token": "^0.4.16",
     "@agoric/assert": "^0.3.15",
+    "@agoric/telemetry": "^0.1.0",
     "@endo/captp": "^1.10.12",
     "@agoric/cosmic-swingset": "^0.34.4",
     "@agoric/eventual-send": "^0.14.0",

packages/solo/src/start.js

@@ -15,6 +15,7 @@ import anylogger from 'anylogger';
 // import djson from 'deterministic-json';
 
 import { assert, details as X } from '@agoric/assert';
+import { makeSlogSenderFromModule } from '@agoric/telemetry';
 import {
   loadSwingsetConfigFile,
   buildCommand,
@@ -156,11 +157,14 @@ const buildSwingset = async (
     }
     await initializeSwingset(config, argv, hostStorage);
   }
-  const slogFile = process.env.SOLO_SLOGFILE;
+  const { SOLO_SLOGFILE: slogFile, SOLO_SLOGSENDER } = process.env;
+  const slogSender = await makeSlogSenderFromModule(SOLO_SLOGSENDER, {
+    stateDir: kernelStateDBDir,
+  });
   const controller = await makeSwingsetController(
     hostStorage,
     deviceEndowments,
-    { slogFile },
+    { slogFile, slogSender },
   );
 
   async function saveState() {

packages/telemetry/src/index.js

@@ -3,6 +3,8 @@
 import { MeterProvider } from '@opentelemetry/metrics';
 import { PrometheusExporter } from '@opentelemetry/exporter-prometheus';
 
+export * from './make-slog-sender.js';
+
 /**
  * @typedef {Object} Powers
  * @property {{ warn: Console['warn'] }} console

packages/telemetry/src/make-slog-sender.js

@@ -0,0 +1,26 @@
+// @ts-check
+import path from 'path';
+
+export const DEFAULT_SLOG_SENDER_MODULE =
+  '@agoric/telemetry/src/flight-recorder.js';
+
+export const makeSlogSenderFromModule = async (
+  slogSenderModule = DEFAULT_SLOG_SENDER_MODULE,
+  makerOpts = {},
+) => {
+  if (!slogSenderModule) {
+    return undefined;
+  }
+
+  if (slogSenderModule.startsWith('.')) {
+    // Resolve relative to the current working directory.
+    slogSenderModule = path.resolve(slogSenderModule);
+  }
+
+  console.warn(`Loading makeSlogSender from ${slogSenderModule}`);
+  const { makeSlogSender: maker } = await import(slogSenderModule);
+  if (typeof maker !== 'function') {
+    throw Error(`${slogSenderModule} did not export a makeSlogSender function`);
+  }
+  return maker(makerOpts);
+};