4 Commits (96b652fb523801cf3f9ac3382534ef1735eb3d86)

Author	SHA1	Message	Date
Jonathan Perret	96b652fb52	Support HTTP long polling as an alternative to WebSockets (#859) ... The motivation for supporting an alternative to WebSockets is that while all browsers supported by Grist offer native WebSocket support, some networking environments do not allow WebSocket traffic. Engine.IO is used as the underlying implementation of HTTP long polling. The Grist client will first attempt a regular WebSocket connection, using the same protocol and endpoints as before, but fall back to long polling using Engine.IO if the WebSocket connection fails. Include these changes: - CORS websocket requests are now rejected as a stronger security measure. This shouldn’t affect anything in practice; but previously it could be possible to make unauthenticated websocket requests from another origin. - GRIST_HOST variable no longer affects CORS responses (also should not affect anything in practice, as it wasn't serving a useful purpose)	2 months ago
Dmitry S	4d9bbf6263	(core) Exit more cleanly on unhandled errors, and handle errors writing to Clients. ... Summary: - Node has a strong recommendation to assume bad state and exit promptly on unhandled exceptions and rejections. We follow it, and only make an effort to clean up before exiting, and to log the error in a more standard way. - The only case seen in recent month of an unhandled rejection was for attempting to write overly large JSON to a Client websocket. Ensure that's handled, and add a test case that artificially reproduces this scenario. Test Plan: Added a test case for failing write to Client, and a test case that unhandled errors indeed kill the server but with an attempt at cleanup. Reviewers: georgegevoian Reviewed By: georgegevoian Differential Revision: https://phab.getgrist.com/D4124	6 months ago
Dmitry	c9489e4a61	Fix ManyFetches test, and include into grist-core a needed upgrade to the 'ws' package. (#614) ... This is a follow-up fix to 526a5df157.	10 months ago
Dmitry S	526a5df157	(core) Manage memory used for websocket responses to reduce the risk of server crashes. ... Summary: - Implements MemoryPool for waiting on memory reservations. - Uses MemoryPool to control memory used for stringifying JSON responses in Client.ts - Limits total size of _missedMessages that may be queued for a particular client. - Upgrades ws library, which may reduce memory usage, and allows pausing the websocket for testing. - The upgrade changed subtle behavior corners, requiring various fixes to code and tests. - dos.ts: - Includes Paul's fixes and updates to the dos.ts script for manual stress-testing. - Logging tweaks, to avoid excessive dumps on uncaughtError, and include timestamps. Test Plan: - Includes a test that measures heap size, and fails without memory management. - Includes a unittest for MemoryPool - Some cleanup and additions to TestServer helper; in particular adds makeUserApi() helper used in multiple tests. - Some fixes related to ws upgrade. Reviewers: paulfitz Reviewed By: paulfitz Differential Revision: https://phab.getgrist.com/D3974	10 months ago