Issue while parsing Complex Regular expression in YAML file

[Pawan Kumar]

Issue is coming while parsing the following regular expression

"^[a-zA-Z0-9-+.#$%&~*\/=?^_ '\"\\!]{9,430}$"

Tried other options like

"^[a-zA-Z0-9-+.#$%&~*\/=?^_ '\\\"\\!]{9,430}$"

'^[a-zA-Z0-9-+.#$%&~*\/=?^_ '\"\\!]{9,430}$'

Issues coming

  stderr: |-
    while scanning a double-quoted scalar
      in "<string>", line 373, column 56:
         ... ex: '^[a-zA-Z0-9-+.#$%&~*/=?^_ '"\!]{9,430}$'
                                                                            ^
    found unknown escape character '!'
      in "<string>", line 373, column 58:
         ... : '^[a-zA-Z0-9-+.#$%&~*/=?^_ '"\!]{9,430}$'
                                                                         ^

----------------------------------------------------------------------------------------------------

ERROR! Syntax Error while loading YAML.
  expected <block end>, but found '<scalar>'

The offending line appears to be:

context_regex: '''^[a-zA-Z0-9-+.#$%&~*\/=?^_ '\"\\!]{9,430}$'''
                                                                                                              ^ here

-----------------------------------------------------------------------------------------------------

ERROR! Syntax Error while loading YAML.
  found character '`' that cannot start any token

The offending line appears to be:

context_regex: ```^[a-zA-Z0-9-+.#$%&~*\/=?^_ '\"\\!]{9,430}$```
                          ^ here

-------------------------------------------------------------------------------------------------------------------

ERROR! Syntax Error while loading YAML.
  found character '`' that cannot start any token

context_regex: `^[a-zA-Z0-9-+.#$%&~*\/=?^_ '\"\\!]{9,430}$`
                          ^ here

-------------------------------------------------------------------------------------------------------------------

ERROR! Syntax Error while loading YAML.
  expected <block end>, but found '<scalar>'

context_regex: '^[a-zA-Z0-9-+.#$%&~*\/=?^_ \'\\\!]{8,240}$'
                                                                                     ^ here

-------------------------------------------------------------------------------------------------------------------

ERROR! Syntax Error while loading YAML.
  expected <block end>, but found '<scalar>'

context_regex: '^[a-zA-Z0-9-+.#$%&~*\/=?^_ \'\\!]{9,430}$'
                                                                                     ^ here
------------------------------------------------------------------------------------------------------------------

ERROR! Syntax Error while loading YAML.
  expected <block end>, but found '<scalar>'

context_regex: '^[a-zA-Z0-9-+.#$%&~*\/=?^_ \'\\\"\\!]{9,430}$'
                                                                                      ^ here

------------------------------------------------------------------------------------------------------------------

ERROR! Syntax Error while loading YAML.
  expected <block end>, but found '<scalar>'

context_regex: '^[a-zA-Z0-9-+.#$%&~*\/=?^_ \'\\"\\!]{8,240}$'

                                                                                          ^ here

-----------------------------------------------------------------------------------------------------------------------

ERROR! Syntax Error while loading YAML.
  expected <block end>, but found '<scalar>'

context_regex: '^[a-zA-Z0-9-+.#$%&~*\/=?^_ \'\"\\!]{9,430}$'
                                                                                   ^ here

-----------------------------------------------------------------------------------------------------------------------

ERROR! Syntax Error while loading YAML.
  found unknown escape character '^'

context_regex: "\\\^[a-zA-Z0-9-+.#$%&~*\/=?^_ '\"\\!]{9,430}$\\\"
                                ^ here

-----------------------------------------------------------------------------------------------------------------------------

ERROR! Syntax Error while loading YAML.
  found unknown escape character '!'

context_regex: "^[a-zA-Z0-9-+.#$%&~*\/=?^_ '\\\!]{9,430}$"
                                                                                     ^ here

------------------------------------------------------------------------------------------------------------------------------

[Vladimir Botka]

On Wed, 3 Jun 2020 22:46:37 -0700 (PDT)
Pawan Kumar <pawa...@gmail.com> wrote:

> '^[a-zA-Z0-9-+.#$%&~*\/=?^_ '\"\\!]{9,430}$'

Try this

'^[a-zA-Z0-9-+.#$%&~*/=?^_''\"!]{9,430}$'

In "single-quoted style" only the single-quote must be escaped ('')
https://yaml.org/spec/1.2/spec.html#id2788097

For example (occurrences left out)

- debug:
msg: OK
loop: ['a', '+', '}']
when: item is match(context_regex)
vars:
context_regex: '^[a-zA-Z0-9-+.#$%&~*/=?^_''\"!]$'

gives

ok: [localhost] => (item=a) => {
"msg": "OK"
}
ok: [localhost] => (item=+) => {
"msg": "OK"
}
skipping: [localhost] => (item=})

HTH,

-vlado

--
Vladimir Botka

[Vladimir Botka]

The backslash must be escaped too (\\). For example,

- debug:
msg: OK
loop: [' ', "'", '\', '"', '!', '}']

when: item is match(context_regex)
vars:
context_regex: '^[a-zA-Z0-9-+.#$%&~*/=?^_ ''\\"!]$'

gives

ok: [localhost] => (item= ) => {
"msg": "OK"
}
ok: [localhost] => (item=') => {
"msg": "OK"
}
ok: [localhost] => (item=\) => {
"msg": "OK"
}
ok: [localhost] => (item=") => {
"msg": "OK"
}
ok: [localhost] => (item=!) => {