Gk-nfc-reader NPM

gk-nfc-reader

Reads the Personal Data of German eGK via NFC

API documentation

Types

The state of the GKNFCReader. value is only defined if reading the data was successful. value holds the data of the MF / DF.HCA / EF.PD file, which is the personal data of the card holder.

enum State {
  idle = "idle",
  loading = "loading",
  success = "success",
  error = "error",
}

export interface PersonalData {
  lastname: string;
  firstname: string;
  birthday: string;
  gender: string;
  street: string;
  housenumber: string;
  zipCode: string;
  city: string;
  counrtyCode: string;
  insuranceId: string;
}

export interface NFCReaderState {
  state: State;
  value?: PersonalData;
  error?: string;
}

This type defines what kind of information can be sent to the GKNFCReader. For now Only the can (Card Acess Number) is needed and used to get a hold of the personal data.

export interface ReadPersonalDataOptions {
  can: string;
  pin?: string;
  checkBrainpoolAlgorithm?: boolean;
}

useReadPersonalData hook

This hook is the main part of this paackge. It connectes to the GKNFCReader via the can, subscribes to the NFCReaderState, and updates the results which holds a summary of all commands that were send between the card and th NFC redaer device (smartphone). The hook therefore returns the state, the resultand the readPersonalData(data: ReadPersonalDataOptions) function.

For easy integration use provided usage example

import {
  Button,
  Text,
  SafeAreaView,
  TextInput,
  StyleSheet,
} from "react-native";
import { useState } from "react";
import { useReadPersonalData } from "gk-nfc-reader";

const App = () => {
  const [can, setCan] = useState("");
  const { result, state, readPersonalData } = useReadPersonalData();
  return (
    <SafeAreaView style={styles.container}>
      <TextInput
        style={styles.input}
        placeholder="Type something"
        value={can}
        onChangeText={(newText) => setCan(newText)} // Update state on text change
      />
      <Button title="Read HCA.PD" onPress={() => readPersonalData({ can })} />
      <Text style={styles.text}>
        {" "}
        State: {state.state} {JSON.stringify(state.value)} {state.error}
      </Text>
      <Text style={styles.text}> Res: {res}</Text>
    </SafeAreaView>
  );
};

export default App;

const styles = StyleSheet.create({
  container: {
    flex: 1,
  },
  input: {
    height: 40,
    borderColor: "gray",
    borderWidth: 1,
    marginBottom: 20,
    paddingLeft: 10,
  },
  text: {
    fontSize: 18,
  },
});

Installation in managed Expo projects

npx expo install gk-nfc-reader

Afterwards add the expo-config-plugin to the app.json

//app.json

...
"plugins": [
    ...
      [
        "../app.plugin.js",
        {
          "nfcReaderUsageDescription": "NFC Test", // you can put any description here
          "deploymentTarget": "14.0" // we need a minimum of 14.0
        }
      ]
    ]