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)
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
Summary:
- Handle the possibility that any access to localStorage causes error.
- Move getStorage() and getSessionStorage() safe functions to a separate file.
- Use these safe functions in more places.
Test Plan:
Added a test case, using a webdriver instance that blocks third-party cookies,
to enforce third-party restrictions. Added to gristUtil a way to override the
webdriver instance.
Reviewers: jarek
Reviewed By: jarek
Differential Revision: https://phab.getgrist.com/D3719
Summary:
- Substantial refactoring of the logic when the server fails to send some
messages to a client.
- Add seqId numbers to server messages to ensure reliable order.
- Add a needReload flag in clientConnect for a clear indication whent the
browser client needs to reload the app.
- Reproduce some potential failure scenarios in a test case (some of which
previously could have led to incorrectly ordered messages).
- Convert other Comm tests to typescript.
- Tweak logging of Comm and Client to be slightly more concise (in particular,
avoid logging sessionId)
Note that despite the big refactoring, this only addresses a fairly rare
situation, with websocket failures while server is trying to send to the
client. It includes no improvements for failures while the client is sending to
the server.
(I looked for an existing library that would take care of these issues. A relevant article I found is https://docs.microsoft.com/en-us/azure/azure-web-pubsub/howto-develop-reliable-clients, but it doesn't include a library for both ends, and is still in review. Other libraries with similar purposes did not inspire enough confidence.)
Test Plan: New test cases, which reproduce some previously problematic scenarios.
Reviewers: paulfitz
Reviewed By: paulfitz
Differential Revision: https://phab.getgrist.com/D3470
Summary:
We used tslint earlier, and on switching to eslint, some rules were not
transfered. This moves more rules over, for consistent conventions or helpful
warnings.
- Name private members with a leading underscore.
- Prefer interface over a type alias.
- Use consistent spacing around ':' in type annotations.
- Use consistent spacing around braces of code blocks.
- Use semicolons consistently at the ends of statements.
- Use braces around even one-liner blocks, like conditionals and loops.
- Warn about shadowed variables.
Test Plan: Fixed all new warnings. Should be no behavior changes in code.
Reviewers: paulfitz
Reviewed By: paulfitz
Differential Revision: https://phab.getgrist.com/D2831
Summary: add user and docId to heartbeat logging
Test Plan: checked manually
Reviewers: dsagal
Reviewed By: dsagal
Differential Revision: https://phab.getgrist.com/D2784
Summary:
This changes how user attributes are loaded. They are now loaded
directly from sqlite, with per-session caching. Optimizations
considered but not addressed yet are (1) adding indexes to user attribute
tables and (2) swapping in a thinner sqlite wrapper.
The main benefit of this diff is that changes to user attribute
tables now work. Clients whose user attributes are not changed
see no effect; clients whose user attributes have changed have
their document reloaded.
For the purposes of testing, the diff includes a tweak to
GristWSConnection to be "sticky" to a specific user when reloading
(and support machinery on the server side to honor that). Until
now, if a GristWSConnection reloads, it uses whatever the current
default user is in the cookie-based session, which can change.
This was complicating a test where multiple users were accessing
the same document via different clients with occasional document
reloads.
Code for updating when schema or rule changes happen is moved
around but not improved in any meaningful way in this diff.
Test Plan: existing tests pass; extended test
Reviewers: dsagal
Reviewed By: dsagal
Differential Revision: https://phab.getgrist.com/D2685
Summary:
This moves all client code to core, and makes minimal fix-ups to
get grist and grist-core to compile correctly. The client works
in core, but I'm leaving clean-up around the build and bundles to
follow-up.
Test Plan: existing tests pass; server-dev bundle looks sane
Reviewers: dsagal
Reviewed By: dsagal
Differential Revision: https://phab.getgrist.com/D2627
Jonathan Perret
Dmitry S
Paul Fitzpatrick