Escaping single quotes for shell

Question

I'm passing ENVs with JSON into Docker. I need to use a string on the shell for a parameter. In the shell, the right way to escape a single quote is by using '\\'' . So, "Tom's Market" becomes "Tom'\\''s Market" as in:

docker run -it -e FOO='["Tom'\''s Market"]' ...

Ruby's Shellwords does not appear to do this.

Shellwords.shellescape('["Tom\'s Market"]')
#=> \[\"Tom\'s\ Market\"\]

So I wanted to use simple find/replace:

'["Tom\'s Market"]'.gsub("'", "'\\''")
#=> ["Tom's Market"]'s Market"]

I don't know what's going on there. Can someone help me?

Answer 1

Well, backslash is how you escape in ruby strings. To escape it you need another backslash.

The is usually to add backslashes until it works

puts %q{["Tom's Market"]}.gsub("'", "'\\\\''")
# ["Tom'\''s Market"]

Answer 2

Shellwords.escape的结果旨在不加引号地使用：

docker run -it -e FOO=\[\"Tom\'s\ Market\"\]