Added support to ipv4 and ipv6 on URL validation

[ricardobessadacosta]

Related to issue: #14

Description:
Replaced the old regex to accept IPv4 and IPv6 on Webhook URL based on RFC 3986.

  host        = IP-literal / IPv4address / reg-name
  IP-literal = "[" ( IPv6address / IPvFuture  ) "]"

  IPv4address = dec-octet "." dec-octet "." dec-octet "." dec-octet

  dec-octet   = DIGIT                 ; 0-9
              / %x31-39 DIGIT         ; 10-99
              / "1" 2DIGIT            ; 100-199
              / "2" %x30-34 DIGIT     ; 200-249
              / "25" %x30-35          ; 250-255

  IPv6address =                            6( h16 ":" ) ls32
              /                       "::" 5( h16 ":" ) ls32
              / [               h16 ] "::" 4( h16 ":" ) ls32
              / [ *1( h16 ":" ) h16 ] "::" 3( h16 ":" ) ls32
              / [ *2( h16 ":" ) h16 ] "::" 2( h16 ":" ) ls32
              / [ *3( h16 ":" ) h16 ] "::"    h16 ":"   ls32
              / [ *4( h16 ":" ) h16 ] "::"              ls32
              / [ *5( h16 ":" ) h16 ] "::"              h16
              / [ *6( h16 ":" ) h16 ] "::"

  ls32        = ( h16 ":" h16 ) / IPv4address
              ; least-significant 32 bits of address

  h16         = 1*4HEXDIG
              ; 16 bits of address represented in hexadecimal

Tried to let the regex more readable and easy to understand. Suggestions would be appreciated.

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[mihirsoni]

Hi @ricardobessa1

Thank you for your contribution. Could you add few Unit Test cases for this change ?

[ricardobessadacosta]

Hello @mihirsoni ,

I have added some Unit Test cases.

[mihirsoni]

Thank for changes ! Looks good to me.

[dbbaughe]

Thanks!

[Cyb3rSn0rlax]

still having this issue with plugin 1.7.0 kibana version 7.6.1:

[Lyr]

still having this issue with plugin 1.7.0 kibana version 7.6.1:

I guess this is caused by the version of your browser, I've got this same issue on my side and I've fixed with another browser.