How to split a key-value string into array pairs?

Question

How can I split the following String into key-value pairs using bash?

SOURCE="'key1=val 1' 'key2=val 2'"

My output goal is:

key1=val 1
key2=val 2

• I can only input a single String as a variable
• I cannot pass the variable as array
• I want to output only the key-value pair plain as is
• I want to honor the quotes, as I don't know how to separate the key-value pairs else
• My keys never contain spaces, but values will

Answer 1

I understand that you are free to define the SOURCE format, so you can make sure, you always have a whitespace between two definitions. In this case, you can remove the ticks at the start and beginning and replace all occerences of ' ' with a newline:

echo "$SOURCE" | sed "s/^'//;s/'$//;s/' '/"'\
'/g

Note that I need to switch from double quoting to single quoting to quote the line break.

If you also want to remove the backlash from an escaped tick, do

echo "'key1=foo bar' 'key2=I\'m okay'" | sed "s/^'//;s/'$//;s/' '/"'\
'"/g;s/\\\\'/'/g"

An example to make this fail would be SOURCE="'key1=foo\' ' 'key2=bar'"