achlipala / frapapp Goto Github PK

This may or may not be a bug. An alert with following error message shows up on the student page, after lingering for a few minutes:

Server: Error querying remote server for messages: 500

It appears to have no other effect, and doesn't e.g. log out the visitor. After clicking the 'Ok' button, You can still navigate to other private pages.

Steps to reproduce:

1. Navigate to https://frap.csail.mit.edu/Private/student/_.
2. Wait ~10 minutes.

In the "News" tab, my most recent announcement title is rendered as

Extra office hours happening now-noon & 1:30-2:30 -- eom

The & should be just a &.

I thought Ur/Web is supposed to get all escaping right by design -- how could this happen?

I used the grade upload function to upload reviews like

It looks like you understood conceptually how to construct a bad program, but what you wrote down in Coq is not what you meant. I think the confusion comes from the fact that the semicolon can have two meanings: It can separate list elements, but it's also used in the notation for (Bind c f), which is printed as "x <- c; f x".<br/>
If you write<br/>
<br/>
Example bad: prog :=<br/>
  [Lock 1 ; Lock 2] ++ [Lock 2 ; Lock 1].<br/>
<br/>
you get a program consisting of 4 threads. What you meant is<br/>
<br/>
Example bad: prog := [(_ <- Lock 1; Lock 2); (_ <- Lock 2; Lock 1)].<br/>
<br/>
If you think your difficulties were related to understanding "Bind", please ask about it in the office hours!

This is valid HTML according to https://validator.w3.org/check, but when I checked the display on the website, it says HTML error: Unknown HTML tag -.

I suspect it's related to the semicolon, but apparently a semicolon inside quotes does not cause a problem.

The fix for this instance was easy: Just manually edit using the website.

But there are two problems to fix:

• If you upload HTML which the website doesn't consider valid, it should show an error during the upload.
• It should accept all valid HTML.

I got an email notification with the following content:

Let it be known that there is a new MIT 6.822 Pset 5 forum message posted by [...] in the thread [...]. It reads:

HTML error: Unknown HTML tag font

On the FRAP website, the message is displayed correctly.

If a student has an issue like "rewrite doesn't work", they should be able to search the forum before posting a question. It would also be useful for staff to find old threads they vaguely remember.

I'd like to reference a forum thread in another thread, eg to say "your problem has probably been solved there". URLs or any other form of referencing would work.

It would be handy if the subject and sender of email notifications were more descriptive. For instance, the sender could be

Firstname Lastname <[email protected]>

and the subject could be

[MIT 6.822] Title of forum thread

or, if it's a reply,

Re: [MIT 6.822] Title of forum thread

And as a bonus, if the In-Reply-To: header was set, mail clients would group it by thread (it seems that the Message-ID: header is already set).

On the staff page, I can see the "Hints" tab, but on the students page, there is no hints tab any more. Looks like this was an accident in 2f0cdb5.

We got lucky with most student/staff accesses coming from the same time zone, before the adventures of this semester! Reported by @mayasankar.

In the global forum, there's a thread fibonacci invariant [private], opened by student A, and it has an answer by student B, but it looks more like an answer by an instructor (and if it's by a student, it means that private threads are not private, so there's an issue in any case).