ruby json data lookup with regex-CodePudding

I have a json file ou.json:

{
    "ProdInf": {
        "regex": "^(?i)nyinf-p(\\d )$",
        "ou": "OU=Inf,OU=Prod,OU=Servers,DC=example,DC=local"
    },
    "ProdHyperV": {
        "regex": "^(?i)nyhyp-p(\\d )$",
        "ou": "OU=HyperV,OU=Prod,OU=Servers,DC=example,DC=local"
    },
    "ProdRDS": {
        "regex": "^(?i)nyrds-p(\\d )$",
        "ou": "OU=RDS,OU=Prod,OU=Servers,DC=example,DC=local"
    }
    "Default": {
        "regex": "zzz",
        "ou": "OU=Servers,DC=example,DC=local"
    }

}

I have:

require 'json'
computername = "nyhyp-p24"

json_file = File.read("./ou.json")
json_hash = JSON.parse(json_file)

then be able to retrieve all the regex in the hash, and evaluate computername against each regex, and if it is a match return the appropriate ou.first

in the example above, ou should equal "OU=HyperV,OU=Prod,OU=Servers,DC=example,DC=local"

if there is no match it should return default.ou

CodePudding user response：

I add extra slashes to escape them in the JSON

Like this: "^(?i)nyrds-p(\\d )$" --> "^(?i)nyrds-p(\\\\d )$"

require "json"

json =
  <<~JSON
    {
      "ProdInf": {
        "regex": "^(?i)nyinf-p(\\\\d )$",
        "ou": "OU=Inf,OU=Prod,OU=Servers,DC=example,DC=local"
      },
      "ProdHyperV": {
        "regex": "^(?i)nyhyp-p(\\\\d )$",
        "ou": "OU=HyperV,OU=Prod,OU=Servers,DC=example,DC=local"
      },
      "ProdRDS": {
        "regex": "^(?i)nyrds-p(\\\\d )$",
        "ou": "OU=RDS,OU=Prod,OU=Servers,DC=example,DC=local"
      },
      "Default": {
        "regex": "zzz",
        "ou": "OU=Servers,DC=example,DC=local"
      }
    }
  JSON

configs = JSON.parse(json, symbolize_names: true)

Then you can define some method like this

def find_ou(computer_name, configs)
  configs
    .find { |_, config| computer_name.match?(%r{#{config[:regex]}}) }
    &.last
    &.dig(:ou) || configs[:Default][:ou]
end

And then

find_ou("nyhyp-p24", configs)
# => "OU=HyperV,OU=Prod,OU=Servers,DC=example,DC=local"

find_ou("nyinf-p26", configs)
# => "OU=Inf,OU=Prod,OU=Servers,DC=example,DC=local"

find_ou("something else", configs)
# => "OU=Servers,DC=example,DC=local"