Some experiences and feedback about falcon command

[wildjcrt]

This is an experience feedback.

I started to try falcon serve on MBP and I felt it quite annoyed me when I always typo as falcon server.
I then thought what if falcon command supports aliases like falcon server or falcon s.

In 5xruby after hack, next day after RubyConf Taiwan 2019, I started to try coding on subcommand aliases.

In the beginning, I code for falcon s as alias of falcon serve because it is shorter and similar to rails s.
Referece from rails/commands.rb, I wrote some codes blow.

require 'falcon/command'

aliases = {
  'server' => 'serve',
  's'  => 'serve',
  'sv' => 'supervisor',
  'v'  => 'virtual',
  'h'  => 'host'
}

command = ARGV.shift
command = aliases[command] || command

Falcon::Command.invoke command, ARGV

Later on, I discussed with @ioquatix and I got some of his considerations.

1. We don't know if there will be a falcon server subcommand in the future.
2. It would be better to show 'did you mean?' part first.

Next round, I tried to send PR for Samovar gem.
When I dived into Samovar::Nested#parse, I found falcon s --bind http://localhost:3000 will go into @default part.
In Falcon::Command::Top, the nested method set up default: 'serve'.
It means when falcon s --bind http://localhost:3000 fail, it should fallback to run falcon serve --bind http://localhost:3000 with input ['s', '--bind', 'http://localhost:3000']. And then it failed because there is also no s subcommand in falcon serve so the return is error message "Could not parse token "s" in:" with falcon serve help text.

@ioquatix and I had another discussion about how to parse subcommand.
I think it would be better to check if input.first =~ /^-.*/ and we can deal something when this situation happens.
Alternative way is that we should parse the whole command and run on a correct order.

For the first way, it would be tricky. It's more better to use begin…rescue…end in @default part instead.The problem is I don't like the code smell because there is a lot of elsif and then begin…rescue…end inside of it.

For the second way, the #parse method will become very complex and some command line features like -- might be broken.

This experience met a lot of different situation and I can't send any PR finally. Just raise issue to record it.

[ioquatix]

Thanks for your feedback and I will consider how we can fix this issue.

[wildjcrt]

Quick add my opinion.

I think falcon is quite good and I want more people to try it. falcon server or falcon s aliases would be easier for most of Rubyists (I believe so) to just start without looking at README.