NetworkManagerContract.sol

pragma solidity^0.6.1;
contract NetworkManagerContract {

    uint nodeCounter;
  
    struct NodeDetails {  
        string nodeName;
        string role; 
        string publickey;
        string enode;
        string ip;
        string id;
    }

    mapping (string => NodeDetails)nodes;
    string[] enodeList;
    
    event print(string nodeName, string role,string publickey, string enode, string ip, string id);

    function registerNode(string memory n, string memory r, string memory p, string memory e, string memory ip, string memory id) public {

        nodes[e].publickey = p;
        nodes[e].nodeName = n;
        nodes[e].role = r;
        nodes[e].ip = ip;
        nodes[e].id = id;
        enodeList.push(e);
        emit print(n, r, p, e, ip, id);
    
    }
   
    function getNodeDetails(uint16 _index) public view returns (string memory n, string memory r, string memory p, string memory ip, string memory e, string memory id, uint i) {
        NodeDetails memory nodeInfo = nodes[enodeList[_index]];
        return (
            nodeInfo.nodeName,
            nodeInfo.role,
            nodeInfo.publickey,
            nodeInfo.ip,
            enodeList[_index],
            nodeInfo.id,
            _index
        );
    }

    function getNodesCounter() public view  returns (uint) {
        return enodeList.length;
    }

    function updateNode(string memory n, string memory r, string memory p, string memory e, string memory ip, string memory id) public {

        nodes[e].publickey = p;
        nodes[e].nodeName = n;
        nodes[e].role = r;
        nodes[e].ip = ip;
        nodes[e].id = id;
        emit print(n, r, p, e, ip, id);
    }

    function getNodeList(uint16 i)  public  view   returns (string memory n, string memory r,string memory p,string memory ip,string memory e, string memory id) {
        
        NodeDetails memory nodeInfo = nodes[enodeList[i]];
        return (
            nodeInfo.nodeName,
            nodeInfo.role,
            nodeInfo.publickey,
	        nodeInfo.ip,
            enodeList[i],
            nodeInfo.id
        );
    }

}