您可以尝试一下；

grep -oE '"[^"]+":[0-9]+'

例如:

user@host:/tmp$ echo '{"foo":29, "bar":30}' | grep -oE '"[^"]+":[0-9]+'
"foo":29
"bar":30

man grep:

 -E, --extended-regexp
              Interpret PATTERN as an extended regular expression (ERE, see below).  (-E is specified by POSIX.)

基本与扩展正则表达式