SSH to iTerm2

Convert host entries from your SSH config file into iTerm2 Dynamic Profiles.

Basically: hosts configured in your ssh config files are automatically turned into iTerm2 profiles with a custom ssh command. These profiles allow for quick connections to your servers using the Profiles manager.

Whut?

From a practical point of view, having all your hosts configured in ssh config files is so easy. You can just ssh <host> in any local terminal and you're in business. So that's what I like to do. A lot of shells also support auto completion based on the configs. Unfortunately, it not always easy to remember the correct names for hosts, as I have a number extensive config files for several of my clients.

So I want a list of those hosts, but ideally they should be based on config files. Most apps out there allow you to configure some kind of favorites/connections/profiles, but it's always manual.

I've always been a big iTerm2 fan, tried most of the alternatives but always ended up coming back. Royal TSX came close, but again my favorites and my ssh configs digressed too much to my liking.

So finally ended up with "why can't I just use my SSH hosts as favorites?". Turns out iTerm2 has something called Dynamic Profiles. It is continuously monitoring a folder on the system (~/Library/Application Support/iTerm2/DynamicProfiles) and if a usable file is written in there (see the documentation for more info) it is parsed and results in profiles in the app.

So of course I wanted to fill this up based on my ssh config. Looking around I found that I wasn't the first with this idea. Unfortunately that solution left me wanting more. So I decided to write my own using the ideas of sshconfig2iterm as a starting point.

Setting up

The only setup this needs is in your ssh config files. Any additional information for iTerm is added via comments so that your files remain 100% readable for SSH. If the comment contains a recognised keyword, it will be used in the profile configuration.

An example Host entry:

# Jump Station to DMZ
Host bastion jumpstation
    # Label Bastion
    # Badge Bastion
    # Tags client.com Production DMZ Jumpstations "tag with spaces"
    # ParentProfile production
    Hostname bastion.client.com
    User me
    IdentityFile ~/.ssh/client.com/bastion.client.com

With this in your configs, you can do a couple things: you can ssh to bastion or jumpstation and it will automatically use the correct hostname, user and identity file.

Notice the comments below the Host entry (Anything before the Host line is assigned to the previous host or thrown out if it's the first). The syntax is the same as your regular ssh keywords: either you can use a space to separate the keyword and its value, or you can use an equal sign (So # Label=Bastion also works).

Run the tool and get the relevant JSON in the correct folder. That's it!

If you run the tool with -s (or --save) it will automatically create a ssh-config.json file in the correct folder. A few seconds later you'll see a new profile in iTerm2. Without the save option a json would be written to the screen. Then it is up to you to make sure it ends up in the profile folder.

As an example, the generated profile could look like this:

{
    "Name": "Bastion",
    "Guid": "a922be92cfab145f6613fa6064a6042d4dae95c5",
    "Badge Text": "Bastion",
    "Dynamic Profile Parent Name": "production",
    "Tags": [
        "client.com",
        "Production",
        "DMZ",
        "Jumpstations",
        "tag with spaces"
    ],
    "Command": "ssh bastion"
}

Include

Include statements (Include ~/.ssh/client.com/config) are supported, all includes will be resolved before any parsing begins.

Config Keywords

Currently the tool only supports a limited amount of config keywords/profile options, but more can be added if needed (see src/DynamicProfiles/options.php).

Guid

At this point this is an auto-generated SHA1 checksum of the host patterns and cannot be overridden. As long as you don't change the patterns the resulting Guid remains the same.

Ignore

If this is found in a Host that would otherwise be included (eg. # Ignore true - value doesn't matter), skip the host.

Label

The label this profile should have in iTerms' profile list.

Badge

If given a value, this text will be shown as a badge in the top right of your terminal.

ParentProfile

Results in a "Dynamic Profile Parent Name"-entry (See the "Parent Profiles" section on the Dynamic Profiles-page for all info)

In short: Since a dynamic profile is not expected to specify all options (the minimal profile is just a Name and Guid), iTerm needs a way to determine values for whatever was omitted. Unless told otherwise it uses the profile marked as default.

I personally have a number of "reference profiles" like production (red background, red tab), staging (orange background, orange tab) etc that I refer to with this option. This allows me to base production hosts on the production profile, clearly visualizing to me that I should be even more careful than usual :-)

One of the massive advantages is that it will copy all values whenever the dynamic profiles are reloaded. This means that you can just change colors or any other setting in the parent profile. All "derived" profiles will be updated automatically.

With regular profiles this is impossible. As soon as you duplicate it it is no longer linked to the original and you'll have to update them individually.

CustomCommand

"Yes" to configure a custom command to execute via the Command keyword. You can just specify a Command though, Custom Command will automatically be added.

Command

Related to above, but the actual command to execute if you want to specify your own. CustomCommand is automatically added if you specify a command, so adding that is optional. If no CustomCommand option is found after the processing of the Host, an ssh <first-host-pattern> custom command will be automatically added for you.

Tags

A space-separated list of tags for the profile. Spaces within tags are supported by double-quoting them ("tag with spaces").

Trigger

Can contain the JSON to define a trigger. This can be specified multiple times (one per trigger). The easiest way to obtain the syntax is to define them manually in iTerm2 and then use "Copy Profile as JSON" under "Other Actions..." to extract it. Just specify it as a one liner to use (example is to open the password manager):

# Trigger {"partial": true, "parameter": "client\/hostname\/username", "regex": "assword:", "action" : "PasswordTrigger"}

Command Line Arguments

An overview of the command line arguments. The default behavior is to use ~/.ssh/config and write the resulting json will to the screen.

--config (-c)

Specify an alternate ssh config file to use. By default ~/.ssh/config is used.

--save (-s)

If this option is specified, the result will be written to a file instead of on the screen. If no value was given, the filename used is ssh-config.json. This option works together with --directory

--directory (-d)

Override the folder to which the resulting file will be written. iTerm2's default watched folder is ~/Library/Application Support/iTerm2/DynamicProfiles

--autotag (-t)

Automatically add a tag to each host. The following substitutions are available:

• %h: First pattern of the Host.
• %p: Every pattern of the Host (Looped substitute, might result in multiple tags)
• %l: Comma separated list of the patterns of the Host
• %d: Directory basename of the config file path (for ~/.ssh/client1/config this would be client1)
• %f: Filename of the config file

All substitutions can be specified as an uppercase letter to use the uppercase version (eg %D would be CLIENT1)

For example --autotag '"Project %D" hostname/%p' would add 2 or more tags to every host. A Project [DIRECTORY NAME] (spaces are supported) and a nested hostname/hostname times the amount of patterns. When using substitutes that can be a list, only the first one will be iterated. If, for example you use %p and %P in a single tag, it will generate separate tags for each value of %p, but all %P instances will be replaced by a comma separated list.

--wildcard (-w)

Process Host entries that contain wildcard patterns instead of skipping them. As they usually result in an unusable profile (ssh server* won't really work), skipping them is the most logical and thus default behavior.

--multi-pattern (-m)

What to do with Host entries that have multiple patterns (Host server1 server1alternative)?

The default behavior (first) is to generate a profile for the first pattern only. Alternate values are ignore (completely ignore the entry) or all to generate a separate profile for each of the patterns.

--uncommented (-u)

Include Hosts that do not have any of the known keywords in their comments instead of ignoring them. This allows you to edit your config files in pieces and will only yields profiles for the Hosts you actually updated.

--bind (-b)

Add a so called Bound Hosts list that includes all patterns and (if present) the HostName. This assists you in using iTerms' Automatic Profile Switching. You'll find the configuration entries on the Advanced page of the Profile.

Various

Tildes (~) in the file references are supported if your PHP installation has posix support (should be the case unless you explicitly disabled it).

As already mentioned: Include statements are recognised and the files referred to are also processed.