Websocket fixes:
1. alert client on failed and lost web socket connections
A long message is given if the connection fails within 1s, which assumes the connection did not succeed. Otherwise, it is a short 'connection closed unexpectedly'.
This also means that clients are notified on server termination (for better or worse).
2. remove superfluous ws-hostname parameter from notebook
This made the notebook server artificially and unnecessarily brittle against tunneling and explicit hostname resolution. Now, the ws_url is defined based on the Origin of the request for the url, so it always matches the http[s] url. This means that it will follow the same tunnel, and the hostname will be already resolved. Resolving the hostname twice makes no sense at all unless the websockets are going to a different server than the http requests.
Implemented as a property, so it should still be easy to change for future cases where it might behave differently (e.g. websockets on a different host, or at a non-root url).
A long message is given if the connection fails within 1s. Otherwise, it is a short 'connection closed unexpectedly'.
This also means that clients are notified on server termination.
The notebook now supports a `--read-only` flag, which allows users to view all notebooks being served but not to edit them or execute any code. These actions are not allowed and the buttons, shortcuts, etc. are removed, but the requests will raise authentication errors if they manage to send the events anyway. Save/print functions remain available.
This flag can be used in two modes:
1. When running an unauthenticated server, one can run a *second* read-only server in the same directory on a public IP address. This will let users connect to the read-only view without having to worry about configuring passwords and certificates for the execution server.
2. When running a server configured with authentication (and hopefully an SSL certificate), starting it with `--read-only` allows unauthenticated users read-only access to notebooks. This means that the same server on a single port can be both used by authenticated users for execution and by the public for viewing the available notebooks.
When using a password, read-only mode allows unauthenticated users
read-only access to notebooks. Editing, execution, etc. are not
allowed in read-only mode, but save/print functions are available.
No kernels are started until an authenticated user opens a notebook.
Adding clear_output to kernel and HTML notebook.
This enables the clearing of output during the execution of a cell. It can be used for simple forms of animation in the notebook.
All buttons, show/hide clickable areas, etc. should have some tooltip describing
what they do. There are jQuery plugins for enhanced tooltips, but this gets
the lightest version working.
closes#436
Various Notebook usability fixes:
- add kernel restart dialog confirmation (it destroys the user session)
- add missing keybindings
- change language from 'terminal mode' to 'in-place execution' which is more descriptive
- adjust spacing/padding and colors slightly for readability and better use of space in small screens.
- add line numbering toggle to code cells. Triggered with C-m-l.
- show keybindings in monospaced font.
- add QuickHelp button that is always visible and at the top.
- add missing keybindings for kernel interrupt/restart from the kbd.
Now multiple calls no longer show multiple instances of the shortcut dialog. Rather, clicking the quick help, or invoking `C-m h` will hide
the dialog if shown.
Matthias BUSSONNIER
Stefan van der Walt
Pablo Winant
Fernando Perez
Fernando Perez
MinRK
Brian Granger
Felix Werner