converge everything into one data folder

server/src/helpers/dataPaths.js

@@ -1,41 +1,49 @@
 // data Paths helper
-// Purpose: Resolves persistent data paths across refactors so services keep loading prior state files.
-// Scope: Preserves runtime behavior by preferring configured/canonical paths while supporting legacy locations.
-const fs = require('fs');
+// Purpose: Defines the single filesystem boundary for all mutable, persistent server data.
+// Scope: Resolves the configured data root and every application-owned mutable path beneath it.
 const path = require('path');
 
 const CANONICAL_DATA_DIR = path.resolve(__dirname, '..', '..', 'data');
-const LEGACY_DATA_DIR = path.resolve(__dirname, '..', 'data');
-
-function pathExists(target) {
-  try {
-    fs.accessSync(target, fs.constants.F_OK);
-    return true;
-  } catch (_err) {
-    return false;
-  }
-}
+const ROVER_SNAPSHOT_DIR_NAME = 'rover-snapshots';
+const RUNTIME_DIR_NAME = 'runtime';
 
 function resolveDataDir() {
   const configured = String(process.env.SERVER_DATA_DIR || '').trim();
   if (configured) return path.resolve(configured);
-  if (pathExists(CANONICAL_DATA_DIR)) return CANONICAL_DATA_DIR;
-  if (pathExists(LEGACY_DATA_DIR)) return LEGACY_DATA_DIR;
   return CANONICAL_DATA_DIR;
 }
 
 function resolveDataPath(fileName) {
-  const configured = String(process.env.SERVER_DATA_DIR || '').trim();
-  if (configured) return path.join(path.resolve(configured), fileName);
+  /*
+    Always join through resolveDataDir instead of repeating environment handling
+    in individual services. This is what makes one SERVER_DATA_DIR mount contain
+    every database, JSON store, generated file, and persistent media directory.
+  */
+  return path.join(resolveDataDir(), fileName);
+}
 
-  const canonicalPath = path.join(CANONICAL_DATA_DIR, fileName);
-  const legacyPath = path.join(LEGACY_DATA_DIR, fileName);
-  if (pathExists(canonicalPath)) return canonicalPath;
-  if (pathExists(legacyPath)) return legacyPath;
-  return canonicalPath;
+function resolveRoverSnapshotDir() {
+  /*
+    Snapshot production, polling, PTZ reads, and health reporting must use the
+    exact same directory. Giving this shared directory a named resolver prevents
+    one of those consumers from drifting back to the former /var/lib location.
+  */
+  return resolveDataPath(ROVER_SNAPSHOT_DIR_NAME);
+}
+
+function resolveRuntimePath(...pathSegments) {
+  /*
+    Disposable files are still files intentionally managed by the Node server.
+    Keeping them below a named runtime directory preserves the single-root
+    filesystem contract without confusing scratch files with durable stores.
+    Callers remain responsible for deleting their own completed work.
+  */
+  return resolveDataPath(path.join(RUNTIME_DIR_NAME, ...pathSegments));
 }
 
 module.exports = {
   resolveDataDir,
   resolveDataPath,
+  resolveRoverSnapshotDir,
+  resolveRuntimePath,
 };

server/src/helpers/dataPaths.test.js

@@ -0,0 +1,49 @@
+// Data Paths Helper Tests
+// Purpose: Pins the one-root persistence contract used by local, systemd, and future container deployments.
+// Scope: Exercises path resolution only and never creates files in the real server data directory.
+const test = require('node:test');
+const assert = require('node:assert/strict');
+const os = require('os');
+const path = require('path');
+const {
+  resolveDataDir,
+  resolveDataPath,
+  resolveRoverSnapshotDir,
+  resolveRuntimePath,
+} = require('./dataPaths');
+
+const originalDataDir = process.env.SERVER_DATA_DIR;
+
+test.afterEach(() => {
+  /*
+    Environment state is process-global. Restore the caller's value after each
+    assertion so this focused test remains safe when it is composed with other
+    tests in the same Node process later.
+  */
+  if (originalDataDir === undefined) delete process.env.SERVER_DATA_DIR;
+  else process.env.SERVER_DATA_DIR = originalDataDir;
+});
+
+test('defaults every persistent path to the canonical server data directory', () => {
+  delete process.env.SERVER_DATA_DIR;
+  const expectedRoot = path.resolve(__dirname, '..', '..', 'data');
+
+  assert.equal(resolveDataDir(), expectedRoot);
+  assert.equal(resolveDataPath('identity.sqlite'), path.join(expectedRoot, 'identity.sqlite'));
+  assert.equal(resolveRoverSnapshotDir(), path.join(expectedRoot, 'rover-snapshots'));
+  assert.equal(resolveRuntimePath('replay-builds'), path.join(expectedRoot, 'runtime', 'replay-builds'));
+});
+
+test('moves every persistent path beneath SERVER_DATA_DIR when it is configured', () => {
+  const configuredRoot = path.join(os.tmpdir(), 'multirover-data-path-test');
+  process.env.SERVER_DATA_DIR = configuredRoot;
+
+  assert.equal(resolveDataDir(), path.resolve(configuredRoot));
+  assert.equal(resolveDataPath('fleet-reports.sqlite'), path.join(configuredRoot, 'fleet-reports.sqlite'));
+  assert.equal(resolveDataPath(path.join('replays', 'example.mp4')), path.join(configuredRoot, 'replays', 'example.mp4'));
+  assert.equal(resolveRoverSnapshotDir(), path.join(configuredRoot, 'rover-snapshots'));
+  assert.equal(
+    resolveRuntimePath('audio-forward', 'uploads'),
+    path.join(configuredRoot, 'runtime', 'audio-forward', 'uploads'),
+  );
+});