shell: use SàT with REPL

shell launch a read–eval–print loop (REPL) with some helpers to launch jp commands. This is useful if you are willing to a session when you’ll use several commands in a row (for e.g. to inspect something on a PubSub service).

start the shell

To start the shell, you just have to enter jp shell. You can eventually specify a profile to use an other one than the default one by entering jp shell -p <some_profile>.

use the shell

Once in the shell, you can launch a command by entering it as usual (without having to specify jp). For instance to get last 2 blog posts from your personal blog, you just have to enter:

> blog get -m 2

There are 2 kinds of commands in the shell:

  • shell commands which are command to manipulate the shell itself
  • jp commands which are the classic commands that you use with jp

The most important thing to remember is that you can use ? (or help which is equivalent) to get the list of commands (shell + jp), and ?<command> (or help <command>) to get information on a shell command. For jp commands, you can use the usual --help argument.

You may move in the commands hierarchy using cmd which can be seen as something roughly equivalent to cd for the filesystem. for instance if you know you’ll work with XMPP blogs, you can enter:

> cmd blog

Then you’ll be in the blog hierarchy, you can check that by entering ?. From there you can use blog commands directly, like in this example to retrieve last 2 blog posts:

blog> get -m 2

You can even go further, e.g. if you know that you’ll do several get command (in this can you’ll only have to specify the arguments of get):

blob> cmd get
blog/get> -m 2

You can use / with cmd, including as first character to indicate that you want to start from root:

blog/get> cmd /pubsub
pubsub> cmd node/info

Similarly, you can use .. to move to parent command:

pubsub/node/info> cmd ..

One of the interesting feature of shell is that you can fix an argument, i.e. indicate the value to use in the next commands. For instance if you’re willing to work on a specific node, you can set its value with use:

blog> use node some_interesting_node

Then you won’t have to specify it anymore for each command. The name of the argument to fix must be the long form. To check which arguments are fixed, just enter use without argument. If an argument is fixed but not used in a command, it will be ignored.

To clear a fixed argument, you have the use_clear command. To clear the node argument set above, just enter:

blog> use_clear node

Without argument, all fixed arguments will be cleared.

Shell commands

Below is a description of shell commands.

cmd

Move in the command hierarchy, this avoid to type again a command if you know you’ll use it several times. See jp-shell_use for explanation and examples

do

Launch a jp command. By default the command is launched if you enter directly its name and arguments, but if a command or argument conflict with a shell command, the shell command will be launched instead. The do command avoid such a situation by always launching a jp command:

> do blog get -m 2

exit

Quit the shell (alias of quit).

help (alias ?)

Give information on available commands or on a specific command, see jp-shell_use for more explanations.

examples

Get general help:

> ?

Get help on do command:

> ?do

quit

Quit the shell

shell (alias !)

Launch an external command.

example

Print a calendar with cal:

> !cal

use

Fix the value of an argument, which will then be set for all following commands, see jp-shell_use for more explanations.

Without argument, show all fixed arguments

examples

Fix the PubSub node (the long name of the argument is used, so it will go to --node):

pubsub> use node some_intersting_node

Show all fixed arguments:

> use

use_clear

Unfix the value of an argument (i.e. use the normal default value). Without argument, it unfixes all arguments.

examples

Clear the node:

pubsub> use_clear node

Clear all arguments:

> use_clear

verbose

Without argument, show if verbose mode is activated. With an argument evaluating to a boolean, activate or deactivate this mode.

In verbose mode, the fixed arguments and the command launched are printed before launching a jp command.

examples

Show if verbose mode is activated:

> verbose

Activate verbose mode:

> verbose on

version

Print current version of jp/Salut à Toi.

whoami

Show the name of the connected profile (the one set with --profile when launching the shell). This profile will be used as default profile.