update headers util

Author: nichtsam

app/root.tsx

@@ -43,10 +43,10 @@ import { getUserId, logout } from './utils/auth.server.ts'
 import { ClientHintCheck, getHints } from './utils/client-hints.tsx'
 import { prisma } from './utils/db.server.ts'
 import { getEnv } from './utils/env.server.ts'
+import { pipeHeaders } from './utils/headers.server.ts'
 import { honeypot } from './utils/honeypot.server.ts'
 import { combineHeaders, getDomainUrl, getUserImgSrc } from './utils/misc.tsx'
 import { useNonce } from './utils/nonce-provider.ts'
-import { pipeHeaders } from './utils/remix.server.ts'
 import { type Theme, getTheme } from './utils/theme.server.ts'
 import { makeTimings, time } from './utils/timing.server.ts'
 import { getToast } from './utils/toast.server.ts'

app/routes/settings+/profile.connections.tsx

@@ -20,7 +20,7 @@ import {
 	providerNames,
 } from '#app/utils/connections.tsx'
 import { prisma } from '#app/utils/db.server.ts'
-import { pipeHeaders } from '#app/utils/remix.server.js'
+import { pipeHeaders } from '#app/utils/headers.server.js'
 import { makeTimings } from '#app/utils/timing.server.ts'
 import { createToastHeaders } from '#app/utils/toast.server.ts'
 import { type Info, type Route } from './+types/profile.connections.ts'

app/utils/headers.server.test.ts

@@ -0,0 +1,39 @@
+import { format, parse } from '@tusbar/cache-control'
+import { expect, test } from 'vitest'
+import { getConservativeCacheControl } from './headers.server.ts'
+
+test('works for basic usecase', () => {
+	const result = getConservativeCacheControl(
+		'max-age=3600',
+		'max-age=1800, s-maxage=600',
+		'private, max-age=86400',
+	)
+
+	expect(result).toEqual(
+		format({
+			maxAge: 1800,
+			sharedMaxAge: 600,
+			private: true,
+		}),
+	)
+})
+test('retains boolean directive', () => {
+	const result = parse(
+		getConservativeCacheControl('private', 'no-cache,no-store'),
+	)
+
+	expect(result.private).toEqual(true)
+	expect(result.noCache).toEqual(true)
+	expect(result.noStore).toEqual(true)
+})
+test('gets smallest number directive', () => {
+	const result = parse(
+		getConservativeCacheControl(
+			'max-age=10, s-maxage=300',
+			'max-age=300, s-maxage=600',
+		),
+	)
+
+	expect(result.maxAge).toEqual(10)
+	expect(result.sharedMaxAge).toEqual(300)
+})

app/utils/remix.server.ts renamed to app/utils/headers.server.ts

@@ -1,6 +1,14 @@
 import { type CacheControlValue, parse, format } from '@tusbar/cache-control'
 import { type HeadersArgs } from 'react-router'
 
+/**
+ * A utility for handling route headers, merging common use-case headers.
+ *
+ * This function combines headers by:
+ * 1. Forwarding headers from the route's loader or action.
+ * 2. Inheriting headers from the parent.
+ * 3. Falling back to parent headers (if any) when headers are missing.
+ */
 export function pipeHeaders({
 	parentHeaders,
 	loaderHeaders,
@@ -61,6 +69,9 @@ export function pipeHeaders({
 	return headers
 }
 
+/**
+ * Given multiple Cache-Control headers, merge them and get the most conservative one.
+ */
 export function getConservativeCacheControl(
 	...cacheControlHeaders: Array<string | null>
 ): string {