chore: telemetry (#2240)

packages/lib/server-only/feature-flags/get-post-hog-server-client.ts

@@ -1,16 +0,0 @@
-import { PostHog } from 'posthog-node';
-
-import { extractPostHogConfig } from '@documenso/lib/constants/feature-flags';
-
-export default function PostHogServerClient() {
-  const postHogConfig = extractPostHogConfig();
-
-  if (!postHogConfig) {
-    return null;
-  }
-
-  return new PostHog(postHogConfig.key, {
-    host: postHogConfig.host,
-    fetch: async (...args) => fetch(...args),
-  });
-}

packages/lib/server-only/site-settings/get-site-setting.ts

@@ -0,0 +1,22 @@
+import { prisma } from '@documenso/prisma';
+
+import type { TSiteSettingSchema } from './schema';
+import { ZSiteSettingSchema } from './schema';
+
+export const getSiteSetting = async <
+  T extends TSiteSettingSchema['id'],
+  U = Extract<TSiteSettingSchema, { id: T }>,
+>(options: {
+  id: T;
+}): Promise<U> => {
+  const { id } = options;
+
+  const setting = await prisma.siteSettings.findFirstOrThrow({
+    where: {
+      id,
+    },
+  });
+
+  // eslint-disable-next-line @typescript-eslint/consistent-type-assertions
+  return ZSiteSettingSchema.parse(setting) as U;
+};

packages/lib/server-only/site-settings/schema.ts

@@ -1,9 +1,12 @@
 import { z } from 'zod';
 
 import { ZSiteSettingsBannerSchema } from './schemas/banner';
+import { ZSiteSettingsTelemetrySchema } from './schemas/telemetry';
 
-// TODO: Use `z.union([...])` once we have more than one setting
-export const ZSiteSettingSchema = ZSiteSettingsBannerSchema;
+export const ZSiteSettingSchema = z.union([
+  ZSiteSettingsBannerSchema,
+  ZSiteSettingsTelemetrySchema,
+]);
 
 export type TSiteSettingSchema = z.infer<typeof ZSiteSettingSchema>;
 

packages/lib/server-only/site-settings/schemas/telemetry.ts

@@ -0,0 +1,14 @@
+import { z } from 'zod';
+
+import { ZSiteSettingsBaseSchema } from './_base';
+
+export const SITE_SETTINGS_TELEMETRY_ID = 'telemetry.installation';
+
+export const ZSiteSettingsTelemetrySchema = ZSiteSettingsBaseSchema.extend({
+  id: z.literal(SITE_SETTINGS_TELEMETRY_ID),
+  data: z.object({
+    installationId: z.string(),
+  }),
+});
+
+export type TSiteSettingsTelemetrySchema = z.infer<typeof ZSiteSettingsTelemetrySchema>;

packages/lib/server-only/site-settings/upsert-site-setting.ts

@@ -1,9 +1,9 @@
 import { prisma } from '@documenso/prisma';
 
-import type { TSiteSettingSchema } from './schema';
+import { type TSiteSettingSchema } from './schema';
 
 export type UpsertSiteSettingOptions = TSiteSettingSchema & {
-  userId: number;
+  userId?: number | null;
 };
 
 export const upsertSiteSetting = async ({

packages/lib/server-only/telemetry/telemetry-client.ts

@@ -0,0 +1,190 @@
+/* eslint-disable require-atomic-updates */
+import fs from 'node:fs/promises';
+import os from 'node:os';
+import path from 'node:path';
+import { PostHog } from 'posthog-node';
+
+import { version } from '../../../../package.json';
+import { prefixedId } from '../../universal/id';
+import { getSiteSetting } from '../site-settings/get-site-setting';
+import { SITE_SETTINGS_TELEMETRY_ID } from '../site-settings/schemas/telemetry';
+import { upsertSiteSetting } from '../site-settings/upsert-site-setting';
+
+const TELEMETRY_KEY = process.env.NEXT_PRIVATE_TELEMETRY_KEY;
+const TELEMETRY_HOST = process.env.NEXT_PRIVATE_TELEMETRY_HOST;
+const TELEMETRY_DISABLED = !!process.env.DOCUMENSO_DISABLE_TELEMETRY;
+
+const NODE_ID_FILENAME = '.documenso-node-id';
+const HEARTBEAT_INTERVAL_MS = 60 * 60 * 1000; // 1 hour
+
+// Version is hardcoded to avoid rollup JSON import issues
+const APP_VERSION = version;
+
+export class TelemetryClient {
+  private static instance: TelemetryClient | null = null;
+
+  private client: PostHog | null = null;
+
+  private heartbeatInterval: NodeJS.Timeout | null = null;
+
+  private installationId: string | null = null;
+  private nodeId: string | null = null;
+
+  private constructor() {}
+
+  /**
+   * Start the telemetry client.
+   *
+   * This will initialize the PostHog client, load or create the installation ID and node ID,
+   * capture a startup event, and start a heartbeat interval.
+   *
+   * If telemetry is disabled via `DOCUMENSO_DISABLE_TELEMETRY=true` or credentials are not
+   * provided, this will be a no-op.
+   */
+  public static async start(): Promise<void> {
+    if (TELEMETRY_DISABLED) {
+      console.log(
+        '[Telemetry] Telemetry is disabled. To enable, remove the DOCUMENSO_DISABLE_TELEMETRY environment variable.',
+      );
+      return;
+    }
+
+    if (!TELEMETRY_KEY || !TELEMETRY_HOST) {
+      console.log('[Telemetry] Telemetry credentials not configured. Telemetry will not be sent.');
+      return;
+    }
+
+    if (TelemetryClient.instance) {
+      return;
+    }
+
+    const instance = new TelemetryClient();
+
+    TelemetryClient.instance = instance;
+
+    await instance.initialize();
+  }
+
+  /**
+   * Stop the telemetry client.
+   *
+   * This will clear the heartbeat interval and shutdown the PostHog client.
+   */
+  public static async stop(): Promise<void> {
+    const instance = TelemetryClient.instance;
+
+    if (!instance) {
+      return;
+    }
+
+    if (instance.heartbeatInterval) {
+      clearInterval(instance.heartbeatInterval);
+    }
+
+    if (instance.client) {
+      await instance.client.shutdown();
+    }
+
+    TelemetryClient.instance = null;
+  }
+
+  private async initialize(): Promise<void> {
+    this.client = new PostHog(TELEMETRY_KEY!, {
+      host: TELEMETRY_HOST,
+      disableGeoip: false,
+    });
+
+    // Load or create IDs
+    this.installationId = await this.getOrCreateInstallationId();
+    this.nodeId = await this.getOrCreateNodeId();
+
+    console.log(
+      '[Telemetry] Telemetry is enabled. Documenso collects anonymous usage data to help improve the product.',
+    );
+    console.log(
+      '[Telemetry] We collect: app version, installation ID, and node ID. No personal data, document contents, or user information is collected.',
+    );
+    console.log(
+      '[Telemetry] To disable telemetry, set DOCUMENSO_DISABLE_TELEMETRY=true in your environment variables.',
+    );
+    console.log(
+      '[Telemetry] Learn more: https://documenso.com/docs/developers/self-hosting/telemetry',
+    );
+
+    // Capture startup event
+    this.captureEvent('telemetry_selfhoster_startup');
+
+    // Start heartbeat
+    this.heartbeatInterval = setInterval(() => {
+      this.captureEvent('telemetry_selfhoster_heartbeat');
+    }, HEARTBEAT_INTERVAL_MS);
+  }
+
+  private captureEvent(event: string): void {
+    if (!this.client || !this.installationId) {
+      return;
+    }
+
+    this.client.capture({
+      distinctId: this.installationId,
+      event,
+      properties: {
+        appVersion: APP_VERSION,
+        installationId: this.installationId,
+        nodeId: this.nodeId,
+      },
+    });
+  }
+
+  private async getOrCreateInstallationId(): Promise<string> {
+    try {
+      // Try to get from site settings
+      const existing = await getSiteSetting({ id: SITE_SETTINGS_TELEMETRY_ID }).catch(() => null);
+
+      if (existing) {
+        if (existing.data.installationId) {
+          return existing.data.installationId;
+        }
+      }
+
+      // Create new installation ID
+      const installationId = prefixedId('installation');
+
+      await upsertSiteSetting({
+        id: SITE_SETTINGS_TELEMETRY_ID,
+        data: { installationId },
+        enabled: true,
+      });
+
+      return installationId;
+    } catch {
+      // If database is not available, generate a temporary ID
+      return prefixedId('installation');
+    }
+  }
+
+  private async getOrCreateNodeId(): Promise<string | null> {
+    const nodeIdPath = path.join(os.tmpdir(), NODE_ID_FILENAME);
+
+    try {
+      const existingId = await fs.readFile(nodeIdPath, 'utf-8');
+
+      if (existingId.trim()) {
+        return existingId.trim();
+      }
+    } catch {
+      // File doesn't exist or can't be read, continue to create
+    }
+
+    // Generate new node ID
+    const nodeId = prefixedId('node');
+
+    try {
+      await fs.writeFile(nodeIdPath, nodeId, 'utf-8');
+    } catch {
+      // Read-only filesystem, use memory for nodeId
+    }
+
+    return nodeId;
+  }
+}