[Fleet] Slow image loading on 7.10

[ph]

From @ruflin

I'm currently playing around with the 7.10 release and every time I load the integrations page, images are loaded with quite some delay. I checked the headers of one of the .svg and it looks as following.

I'm comparing this with the cache headers from the CDN: https://epr.elastic.co/package/apache/0.2.6/img/logo_apache.svg where we have max-age=600.

I remember we had a similar discussion in the past and thought we fixed it. On my localhost, the images load very quickly but the cache headers are the same as in Cloud.

[elasticmachine]

Pinging @elastic/ingest-management (Team:Ingest Management)

[ph]

@ruflin When you said localhost, do you mean everything local even the registry?

[ruflin]

@ph Good question. I'm not sure anymore if I run it from source (means public registry) or the elastic-package setup. But I think it should not matter.

[jfsiii]

Based on these tests, it seems this is default/expected behavior

kibana/src/core/server/http/integration_tests/router.test.ts

Lines 510 to 520 in b3eefb9

	it('does not allow responses to be cached by default', async () => {
	const { server: innerServer, createRouter } = await server.setup(setupDeps);
	const router = createRouter('/');
	router.get({ path: '/', validate: false, options: {} }, (context, req, res) => res.ok());
	await server.start();
	await supertest(innerServer.listener)
	.get('/')
	.expect('Cache-Control', 'private, no-cache, no-store, must-revalidate');
	});

but we can override it

kibana/src/core/server/http/integration_tests/router.test.ts

Lines 522 to 536 in b3eefb9

	it('allows individual responses override the default cache-control header', async () => {
	const { server: innerServer, createRouter } = await server.setup(setupDeps);
	const router = createRouter('/');
	router.get({ path: '/', validate: false, options: {} }, (context, req, res) =>
	res.ok({
	headers: {
	'Cache-Control': 'public, max-age=1200',
	},
	})
	);
	await server.start();
	await supertest(innerServer.listener).get('/').expect('Cache-Control', 'public, max-age=1200');
	});

I'll put up a PR soon