/**
* E2E tests for telemetry configuration.
*
* These tests verify that the DOCS_MCP_TELEMETRY environment variable
* correctly controls telemetry behavior. We parse debug logs to verify
* the telemetry state since the actual PostHog API key is not available
* in test environments.
*
* Expected log messages:
* - "Telemetry disabled (user preference)" - when DOCS_MCP_TELEMETRY=false
* - "Telemetry disabled (no API key configured)" - when enabled but no API key
*
* This specifically tests the fix for GitHub issue #306.
*/
import { spawn } from "node:child_process";
import path from "node:path";
import { describe, expect, it } from "vitest";
import { getCliCommand } from "./test-helpers";
describe("Telemetry E2E", () => {
const projectRoot = path.resolve(import.meta.dirname, "..");
/**
* Run the CLI with specific environment variables and capture output.
* Uses LOG_LEVEL=debug to capture telemetry initialization messages.
* Uses the 'list' command since --help exits before middleware runs.
*/
async function runCliWithEnv(
args: string[],
env: Record<string, string>,
): Promise<{ code: number; stdout: string; stderr: string }> {
return new Promise((resolve, reject) => {
const { cmd, args: cliArgs } = getCliCommand();
const proc = spawn(cmd, [...cliArgs, ...args], {
cwd: projectRoot,
stdio: ["ignore", "pipe", "pipe"],
env: {
...process.env,
// Remove VITEST_WORKER_ID so logger outputs to console
VITEST_WORKER_ID: undefined,
// Enable debug logging to see telemetry messages
LOG_LEVEL: "debug",
// Apply test-specific environment
...env,
},
});
let stdout = "";
let stderr = "";
proc.stdout.on("data", (data) => {
stdout += data.toString();
});
proc.stderr.on("data", (data) => {
stderr += data.toString();
});
proc.on("close", (code) => {
resolve({ code: code ?? 1, stdout, stderr });
});
proc.on("error", (err) => {
reject(err);
});
});
}
it("should log 'user preference' when DOCS_MCP_TELEMETRY=false", async () => {
// Use 'list' command which fully initializes the app including telemetry
const { stdout, stderr } = await runCliWithEnv(["list"], {
DOCS_MCP_TELEMETRY: "false",
});
// Combine output since debug logs may go to either stream
const output = stdout + stderr;
// Should indicate telemetry was disabled by user preference
expect(output).toContain("Telemetry disabled (user preference)");
// Should NOT say "no API key" since user explicitly disabled it
expect(output).not.toContain("Telemetry disabled (no API key configured)");
});
it("should log 'no API key' when DOCS_MCP_TELEMETRY=true but no API key", async () => {
// Run with telemetry explicitly enabled (but no POSTHOG key in test env)
const { stdout, stderr } = await runCliWithEnv(["list"], {
DOCS_MCP_TELEMETRY: "true",
});
const output = stdout + stderr;
// Should indicate telemetry disabled due to missing API key, not user preference
expect(output).toContain("Telemetry disabled (no API key configured)");
// Should NOT say "user preference" since user wanted it enabled
expect(output).not.toContain("Telemetry disabled (user preference)");
});
it("should respect --no-telemetry CLI flag", async () => {
const { stdout, stderr } = await runCliWithEnv(["--no-telemetry", "list"], {
// Don't set env var - let CLI flag control it
});
const output = stdout + stderr;
// CLI flag should result in "user preference" message
expect(output).toContain("Telemetry disabled (user preference)");
});
it("should respect --telemetry=false CLI flag", async () => {
const { stdout, stderr } = await runCliWithEnv(["--telemetry=false", "list"], {});
const output = stdout + stderr;
expect(output).toContain("Telemetry disabled (user preference)");
});
});
