<div dir="ltr"><h3 dir="ltr" style="line-height:1.38;margin-top:8pt;margin-bottom:0pt">User experience</h3> When you SSH into a Snappy system, you currently end up on a shell prompt. Wouldn’t it be great to actually land in Snappy itself? Welcome to Snappy Ubuntu Core 15.04snappy# How do I get started? snappy# helpUsage: <command> [<arg>...] Available commands booted Flag that rootfs booted successfully build Builds a snap package (aliases: bu) config Set configuration for an installed package.[... edited for brievety...] shell Start a shell update Update all installed parts versions (deprecated) please use "list" Simple commands like install, update etc. work as expected: snappy# inforelease: ubuntu-core/15.04/stablearchitecture: amd64frameworks: webdmapps: snappy# list -vName Date Version Developer ubuntu-core 2015-06-11 3 ubuntu* webdm 2015-06-11 0.9 * generic-amd64 2015-06-11 1.1.1 * We should revisit some commands or aliases to have a friendlier, more rewarding user experience, e.g. update could provide some output when no update is available and entering a shell command like ls would hint at using help: snappy# updateSystem is up-to-date!snappy# lsNo such command; “help” for a list of commands Configuration is only possible for snaps that have the required hook and may be set manually by key or globally from an URL, and of course immutable configs can’t be changed. snappy# config(config)# listName Date Version Developer ubuntu-core 2015-06-11 3 ubuntu config-example 2015-06-15 1.0.6 canonical webdm 2015-06-11 0.9 (config)# config xkcd-webserverNo config found for this snap(config)# config ubuntu-core(ubuntu-core)# showautopilot: truetimezone: Etc/UTChostname: localhost.localdomain(ubuntu-core)# set autopilot falseConfig set(ubuntu-core)# exitsnappy# config config-example set -u <a href="https://conf.example.com/config-example.yaml">https://conf.example.com/config-example.yaml</a>Config set A new shell command is provided to start the default user’s interactive shell or to run commands ( under “sh -c”). Goals of snappy shell <ul style="margin-top:0pt;margin-bottom:0pt"><li dir="ltr" style="list-style-type:disc;font-size:14.6666666666667px;font-family:Ubuntu;color:rgb(0,0,0);vertical-align:baseline;background-color:transparent">Deliver a slick console user experience as found when SSH-ing (or telnet-ing) into network equipments such as switches, routers, firewalls etc.</li><li dir="ltr" style="list-style-type:disc;font-size:14.6666666666667px;font-family:Ubuntu;color:rgb(0,0,0);vertical-align:baseline;background-color:transparent">Allows restricting access to the shell while allowing for useful features such as update, install etc. (could be controlled by a new allowed-cli-commands ubuntu-core config or similar)</li><li dir="ltr" style="list-style-type:disc;font-size:14.6666666666667px;font-family:Ubuntu;color:rgb(0,0,0);vertical-align:baseline;background-color:transparent">Smoothes transition into a Comfy world where the regular rootfs becomes smaller and smaller.</li></ul> <h3 dir="ltr" style="line-height:1.38;margin-top:8pt;margin-bottom:0pt">Implementation</h3> This user experience would be delivered by the main “snappy” binary when it’s launched as “snappy-cli” as the basename of argv[0]. If this feature is not enabled by default, or from a shell, you would run “snappy cli” to start an interactive snappy shell session. NB: cli is to avoid confusion with the shell command to run a command or an interactive shell. SSH integration could be done in multiple ways:<ol style="margin-top:0pt;margin-bottom:0pt"><li dir="ltr" style="list-style-type:decimal;font-size:14.6666666666667px;font-family:Ubuntu;color:rgb(0,0,0);vertical-align:baseline;background-color:transparent">integrate a SSH server in snappy itself; I don’t know how hard this is in go today; this might be a worthwhile exercise long-term to get a smaller rootfs</li><li dir="ltr" style="list-style-type:decimal;font-size:14.6666666666667px;font-family:Ubuntu;color:rgb(0,0,0);vertical-align:baseline;background-color:transparent">configure SSH server and login to always start /bin/snappy-cli instead of the user’s shell, then lookup the user’s shell in the passwd database to run the preferred shell with “snappy shell”</li><li dir="ltr" style="list-style-type:decimal;font-size:14.6666666666667px;font-family:Ubuntu;color:rgb(0,0,0);vertical-align:baseline;background-color:transparent">(preferred) configure the user’s shell to /bin/snappy-cli and create a new snappy-only ubuntu-core config for the preferred interactive shell (defaults to /bin/bash); drawback: this would be system-wide as we don’t have per-user configs</li></ol> Questions? Comments? Pile on at: <a href="https://docs.google.com/document/d/1DeR2JoCBDX2C1r6a2wV60uqvi7a89OwHh5gJ19tBZvM/edit" style="text-decoration:none">https://docs.google.com/document/d/1DeR2JoCBDX2C1r6a2wV60uqvi7a89OwHh5gJ19tBZvM/edit</a><div> </div>Cheers, <div>-- </div><div>Loïc Minier</div></div>