I have this shell script in a file named a.sh:
export A='a'
export B=b
export C=1
export D=$USER # say $USER is root
There are some other similar files b.sh, c.sh, etc.
I need to read the shell file, say a.sh, from ruby script and convert it to a Ruby hash:
{ 'A' => 'a', 'B' => 'b', 'C' => 1, 'D' => 'root' }
How to achieve that?
If you have run the bash script prior to the ruby one, you can get doing something like this:
Hash[([ 'A', 'B', 'C', 'D' ] & ENV.keys).map {|x| [x, ENV[x]] }]
where array [ 'A', 'B', 'C', 'D' ] contains valid variable names to create the Hash.
If you need to parse the bash script in ruby, do as follows:
vars = {}
IO.read('shell.sh').each do| line |
if line =~ /^export\s([A-Za-z_][A-Za-z_0-9]*)=\s*(?:['"]([^'"]*)['"]|(.*))\s*$/
(name, value) = [ $1, $2 || $3 ]
value.gsub!( /\$(?:([A-Za-z_][A-Za-z_0-9]*)|{([^{}]+)})/ ) do| match |
ENV[ match[1..-1] ]
end
vars[ name ] = value.gsub(/#.*/, '').strip
end
end
vars
# => {"A"=>"a", "B"=>"b", "C"=>"1", "D"=>"malo"}
ENVconstant.