Get Address Type

FSharp

open Nethereum

open System

open System.Threading

open Nethereum.Web3



exception NetworkOrServerError of string
let exMsg = "Could not communicate with EtherServer"

type AddressTypes = 
    | Contract
    | Account 
    | CommunicationIssue of string


let private RetnFromIsAddressFromContract (web3: Web3) (addr: string): Async<string> = 
        if (web3 = null ) then
            invalidArg "web3" "web3 argument should not be null"

        async {
            try
                let task = web3.Eth.GetCode.SendRequestAsync addr
                let operation = task |> Async.AwaitTask
                let timeout = TimeSpan.FromSeconds 3.0
                let cancel = new CancellationTokenSource()
                let maybeResult = Async.RunSynchronously(operation, timeout.Milliseconds, cancel.Token)
                if (not (maybeResult.StartsWith("0x"))) then
                    return raise <| NetworkOrServerError(exMsg)
                else
                    return maybeResult
            with
                | ex -> return  raise <| NetworkOrServerError(ex.Message)
               
        }


let IsAddressFromContract (addr: string ) (url: string): AddressTypes = 
      let web3  = new Web3(url)
     
      try
          let response = RetnFromIsAddressFromContract web3 addr

          let maybeFound = response |> Async.RunSynchronously
          let rslt = 
              if (maybeFound.StartsWith("0x") && (maybeFound.Length > 3)) then
                  Contract    
              else
                  Account
          rslt
      with 
            | ex ->  CommunicationIssue(ex.Message)


let PrintAddressType (atp: AddressTypes) =
       match atp with
       | Account ->  printfn "This is an Address<account>"
       | Contract ->  printfn "This is an Address<contract>"
       | CommunicationIssue(msg) ->  printfn "Network Issues: <%s>" msg 


[<EntryPoint>]
let main argv =

    //Testing and with expected results
    //Account Address
    let fouts =  IsAddressFromContract "0xa5Acc472597C1e1651270da9081Cc5a0b38258E3" "https://mainnet.infura.io"

    PrintAddressType(fouts)

   
    //Contract address
    let fouts =  IsAddressFromContract "0xde0b295669a9fd93d5f28d9ec85e40f4cb697bae"  "https://mainnet.infura.io"

    PrintAddressType(fouts)

    //Wrong server
    let fouts =  IsAddressFromContract "0xde0b295669a9fd93d5f28d9ec85e40f4cb697bae"  "https://mainnewt.infura.io"

    PrintAddressType(fouts)

    //Bad address structure
    let fouts =  IsAddressFromContract "0xe0b295669a9fd93d5f28d9ec85e40f4cb697bae"  "https://mainnet.infura.io"

    PrintAddressType(fouts)
    0// return an in eger e