chore: avoid log files on disk and move them to console for containers

[fmenezes]

Proposed changes

stop storing log files on disk for containers, log them to console

Checklist

• I have signed the MongoDB CLA

[Copilot]

Pull Request Overview

This PR centralizes container detection logic, removes disk-based log files in container environments, and adds presets to switch between console and file logging.

• Extract detectContainerEnv into a shared util
• Update Telemetry and Server to use container detection for choosing log presets
• Rename and split initializeLogger into setStdioPreset (file logging) and setDockerPreset (console logging)

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
src/common/container.ts	New detectContainerEnv helper to detect Linux container runtime
src/telemetry/telemetry.ts	Remove inline isContainerEnv, import and use detectContainerEnv
src/server.ts	Replace initializeLogger with setStdioPreset/setDockerPreset based on container detection
src/logger.ts	Split logger init into setStdioPreset and setDockerPreset

Comments suppressed due to low confidence (3)

src/common/container.ts:3

• Add unit tests for detectContainerEnv to verify correct container detection across different environments (e.g., with and without /.dockerenv files).

export async function detectContainerEnv(): Promise<boolean> {

src/logger.ts:183

• [nitpick] Public API functions setStdioPreset and setDockerPreset are undocumented; adding JSDoc comments would clarify their behavior and parameters.

export async function setStdioPreset(server: McpServer, logPath: string): Promise<void> {

src/logger.ts:190

• [nitpick] The name setStdioPreset implies STDIO logging but configures a DiskLogger; consider renaming it (e.g., setFilePreset) to avoid confusion.

export function setDockerPreset(server: McpServer): void {

[Copilot]

Consider caching the result of detectContainerEnv in a module‐level variable to avoid repeated filesystem checks when invoked multiple times.

Suggested change

	export async function detectContainerEnv(): Promise<boolean> {
	if (process.platform !== "linux") {
	return false; // we only support linux containers for now
	}
	if (process.env.container) {
	return true;
	let cachedContainerEnv: boolean | null = null;
	export async function detectContainerEnv(): Promise<boolean> {
	if (cachedContainerEnv !== null) {
	return cachedContainerEnv;
	}
	if (process.platform !== "linux") {
	cachedContainerEnv = false; // we only support linux containers for now
	return cachedContainerEnv;
	}
	if (process.env.container) {
	cachedContainerEnv = true;
	return cachedContainerEnv;

[coveralls]

Pull Request Test Coverage Report for Build 16078025857

Details

• 14 of 21 (66.67%) changed or added relevant lines in 3 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.1%) to 74.053%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/server.ts	3	4	75.0%
src/common/container.ts	11	14	78.57%
src/logger.ts	0	3	0.0%

Totals
Change from base Build 16077040616:	-0.1%
Covered Lines:	821
Relevant Lines:	1029

---

💛 - Coveralls