BLISS command line usage¶

BLISS is a library, but a command line interface (BLISS shell) is provided to easily and interactively execute BLISS commands and sequences within an evolved REPL (Read Eval Print Loop).

Usage¶

Use -h flag to get help about bliss command line interface:

% bliss -h
Usage: bliss [-l | --log-level=<log_level>] [-s <name> | --session=<name>] 
             [--no-tmux] [--tmux-debug]
       bliss [-v | --version]
       bliss [-c <name> | --create=<name>]
       bliss [-d <name> | --delete=<name>]
       bliss [-h | --help]
       bliss --show-sessions
       bliss --show-sessions-only

Options:
    -l, --log-level=<log_level>   Log level [default: WARN]
                                  {CRITICAL; ERROR; INFO; DEBUG; NOTSET}
    -s, --session=<session_name>  Start with the specified session
    -v, --version                 Show version and exit
    -c, --create=<session_name>   Create a new session with the given name
    -d, --delete=<session_name>   Delete the given session
    -h, --help                    Show help screen and exit
    --no-tmux                     Deactivate Tmux usage
    --tmux-debug                  Allow debugging keeping tmux alive after Bliss shell exits  
    --show-sessions               Display sessions and tree of sub-sessions
    --show-sessions-only          Display sessions names only

Version¶

Use -v or --version option to get the current version of a BLISS installation:

% bliss --version
BLISS version 0.2

Logging level¶

--log-level or -l defines the logging level of the command line interface.

Sessions¶

Use -s to start an existing session:

% bliss -s test_session
                   __         __   __
                  |__) |   | /__` /__`
                  |__) |__ | .__/ .__/


Welcome to BLISS version erbs5c2 running on PCGUILLOU
                                         in bliss_env Conda environment
Copyright (c) ESRF, 2015-2019

Use --show-sessions option to get the list of available sessions:

% bliss --show-sessions
Available BLISS sessions are:
  flint
  lima_test_session
  test_session

Other commands are also displaying the available sessions:

 % bliss --show-sessions-only

Creation of a new session¶

Use --create or -c to create the skeleton of a new session:

bliss -c eh1
% bliss -c eh1
creating 'eh1' session
Creating: /.../local/beamline_configuration/sessions/eh1_setup.py
Creating: /.../local/beamline_configuration/sessions/eh1.yml
Creating: /.../local/beamline_configuration/sessions/scripts/eh1.py

Removing an existing session¶

--delete or -d removes an existing session:

session YAML file
setup file
default session script (see above)

Multiple panels (Tmux)¶

The BLISS shell uses Tmux to handle multiple panels:

The default one is the “Bliss shell panel” used to enter user commands and to display majority of answers to commands.
The Scan panel is used to display output of scans.

This behavior has been introduced in order to avoid the used to be flooded by scan outputs.

The F5 key is used to switch between theses two panels.

Deactivating Tmux (terminal multiplexer) usage¶

Use --no-tmux to start a Bliss session without the Tmux terminal multiplexer. In a Bliss session without Tmux, the scans output won’t be printed in a separated window and will be shown in the main command line window.

% bliss -s test_session --no-tmux

Debugging within a Tmux session¶

By default, Tmux session is closed as soon as the Bliss shell exits. In the case of an exception that forces Bliss shell to exit, the error information is lost. In order to force Tmux to remains alive after Bliss shell exits, use the option --tmux-debug. Also, it sets the ERROR_REPORT.expert_mode to True to allow a full print of the error and its traceback.

% bliss -s test_session --tmux-debug

Mouse and Key bindings in Tmux¶

MouseButtonLeft:
- drag to select area.
MouseButtonMiddle:
- Paste current selection
MouseButtonRight:
- exit copy-mode
Up or Ctrl-p: go one line up in history (line per line if multi-line command)
Down or Ctrl-n: go one line down in history (line per line if multi-line command)
Ctrl-Left or Alt-b: jump to begining of (previous) word
Ctrl-Right or Alt-f: jump to end of (next) word
PageUp: go one command up in history (group of lines if multi-line command)
PageDown: go one command down in history (group of lines if multi-line command)
Ctrl-a or Home: go to begining of the current line
Ctrl-e or End: go to end of the current line
~~Shift-PageUp: Scroll up terminal buffer by half a page~~
~~Shift-PageDown: Scroll down terminal buffer by half a page~~
Shift-Up: Scroll up terminal buffer by one line
Shift-Down: Scroll down terminal buffer by one line
Shift-Home: go to begining of terminal buffer
Shift-End: go to end of terminal buffer
Ctrl-s: search in current command
Cutting and Pasting:
- Ctrl-w: Cut the word before the cursor, adding it to the clipboard.
- Ctrl-k: (emacs mode) Cut the part of the line after the cursor, adding it to the clipboard.
- Ctrl-u: Cut the part of the line before the cursor, adding it to the clipboard.
- Ctrl-y: (emacs mode) Paste the last thing you cut from the clipboard. The y here stands for “yank”.
Ctrl-Shift-_: Undo your last key press. You can repeat this to undo multiple times.
Function keys:
- F1: ?
- F2: ptpython Menu
- F3: history mode:
  - BLISS shell is hidden
  - terminal is split into two new panels: history and temporary buffer
  - navigation in history is done with usual keys (arrows of Ctrl-<key>)
  - hitting Space copy the current history line into temporary buffer
  - hitting Enter switches back to BLISS shell with temporary buffer pasted
- F4: switches emacs / vi mode (but why the hell to use vi ?)
- F5: switches between BLISS commands shell and scan display panel
- F6: switches to paste mode to paste code from external application forcing no automatic indentation.