conn

A wrapper of ssh/scp, use a alternative way to find a hostname which is hard to remember.

Overview

Conn is useful to people who has lots of hosts that is not suitable for put them into ssh config. These hosts have long names, which is hard to remember and type. This tool build a list of hostnames by using some kind of listers which can retrieve hostnames from various place first. Then this list is filtered according to the user input by several matchers to find the final destination. The default lister grabs hostname from ~/.ssh/known_hosts.

Installation

1. go get go.papla.net/conn
2. put the conn binary in your $PATH
3. (optional) create a symlink point to it with the name of ssh/scp or make aliases:

alias ssh='conn ssh'
alias scp='conn scp'

Usage

Insert conn before calling ssh/scp, or run ssh/scp directly if you do the step 3 of installation. Then you can use a kind of abbreviation to specify hostname.

The abbreviation is a list of tokens separated by .(this can be changed to other characters). These tokens are used to match one or several hosts without to type the full name of the host. The order of the tokens is not important. It should do what you think. The more characters you type, the less results you get.

The default Lister is khost, which requires the target host should be recorded in the known_hosts file.

Examples

• login to remote machine:

conn ssh foo.bar

this may match any hosts with name of foo-bar.com, bar.foo.org, or barr.fooo.toooooo.looooong.

• copy files:

conn scp foo bar.baz:/tmp

will copy foo to a host matching bar.baz.

• list matched names:

conn ssh --list log

can list all log related hosts.

• update cache manaually before it expire:

conn ssh --update foo

will update the cache before match.

Configuration

Conn reads its config file sitting at ~/.conn.conf, you can assign the following options in it. These are default value also.

# path to ssh binary
ssh_bin      = /usr/bin/ssh
# path to scp binary 
scp_bin      = /usr/bin/scp
# lister to use
lister       = khost|
# matchers and their order
matcher      = subtoken, token, substring, string
sep          = .
cache_file   = ~/.conn.cache
cache_expire = 86400

More

The khost lister is not the first lister used by conn. If your facility have an API call to retrieve host names, you may want to add such a lister.

Notes

1. conn do not parse the Host keyword in ~/.ssh/config now.
2. use the full path to run original binary, like /usr/bin/{ssh,scp}.