Java

Without Router - Current Approach

// Assuming this as previous logic without Router
import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.util.HashMap;
import java.util.Map;

public class EntityRequest {
    private static final String BASE_URL = "http://fip-1.dev.sahamati.org.in/fip-simulate";
    private static final String RECIPIENT_ID = "FIP-SIMULATOR";

    public static void main(String[] args) {
        try {
            String response = executeDiscoveryRequest();
            performAnotherOperations(response);
            System.out.println("Account discovery successful.");
        } catch (Exception e) {
            System.out.println("Account discovery failed. Error: " + e.getMessage());
        } finally {
            System.out.println("Account discovery completed.");
        }
    }

    private static String executeDiscoveryRequest() throws Exception {
        String route = "/v2/Accounts/discover";
        HttpClient client = HttpClient.newHttpClient();
        HttpRequest request = getHttpConfig(BASE_URL, route, new HashMap<>(), new HashMap<>(), "POST");
        HttpResponse<String> response = client.send(request, HttpResponse.BodyHandlers.ofString());
        return response.body();
    }

    private static HttpRequest getHttpConfig(String baseUrl, String route, Map<String, String> headers, Map<String, Object> data, String methodType) {
        String url = baseUrl + route;
        String jsonData = mapToJson(data);
        
        HttpRequest.Builder builder = HttpRequest.newBuilder()
                .uri(URI.create(url))
                .POST(HttpRequest.BodyPublishers.ofString(jsonData))
                .header("Content-Type", "application/json");
        
        headers.forEach(builder::header);
        return builder.build();
    }

    private static void performAnotherOperations(String accountDiscoverResponse) {
        System.out.println("Perform another operations with the response: " + accountDiscoverResponse);
    }

    private static String mapToJson(Map<String, ?> data) {
        StringBuilder jsonData = new StringBuilder("{");
        for (Map.Entry<String, ?> entry : data.entrySet()) {
            jsonData.append("\"").append(entry.getKey()).append("\": \"").append(entry.getValue()).append("\",");
        }
        if (!data.isEmpty()) {
            jsonData.deleteCharAt(jsonData.length() - 1);  
        }
        jsonData.append("}");
        return jsonData.toString();
    }
}

With Router Integration

// Changes to implementation to integrate with Router
import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.util.Base64;
import java.util.HashMap;
import java.util.Map;

public class EntityRequest {
    private static final String BASE_URL = "http://fip-1.dev.sahamati.org.in/fip-simulate";
    private static final String RECIPIENT_ID = "FIP-SIMULATOR";
    private static final String ROUTER_URL = "https://api.dev.sahamati.org.in/router";

    public static void main(String[] args) {
        try {
            String response = executeDiscoveryRequest();
            performAnotherOperations(response);
            System.out.println("Account discovery successful.");
        } catch (Exception e) {
            System.out.println("Account discovery failed. Error: " + e);
        } 
    }

    private static String executeDiscoveryRequest() throws Exception {
        String route = "/v2/Accounts/discover";
        String url = BASE_URL + route;
        HttpClient client = HttpClient.newHttpClient();
        HttpRequest request = getHttpConfig(url, new HashMap<>(), new HashMap<>());
        // add Sahamati configuration [Start]
        request = addSahamatiConfiguration(request, route);
        // add Sahamati configuration [End]
        HttpResponse<String> response = client.send(request, HttpResponse.BodyHandlers.ofString());
        return response.body();  
    }

    private static HttpRequest getHttpConfig(String url, Map<String, String> headers, Map<String, Object> data) {
        String jsonData = JSONObject(data); 
        HttpRequest.Builder builder = HttpRequest.newBuilder()
                .uri(URI.create(url))
                .POST(HttpRequest.BodyPublishers.ofString(jsonData))
                .header("Content-Type", "application/json");
        headers.forEach(builder::header);  
        return builder.build();
    }

    private static void performAnotherOperations(String accountDiscoverResponse) {
        System.out.println("Perform another operations with the response: " + accountDiscoverResponse);
    }

    private static String generateBase64EncodedJson(Map<String, String> json) {
        String jsonString = JSONObject(json);  
        return Base64.getEncoder().encodeToString(jsonString.getBytes());
    }

    private static String generateRequestMeta(String recipientId) {
        Map<String, String> context = new HashMap<>();
        context.put("recipient-id", recipientId);
        return generateBase64EncodedJson(context);
    }

    private static HttpRequest addSahamatiConfiguration(HttpRequest request, String route) {
        String newUrl = ROUTER_URL + route;
        HttpRequest.Builder builder = HttpRequest.newBuilder()
                .uri(URI.create(newUrl))
                .method(request.method(), request.bodyPublisher().orElse(HttpRequest.BodyPublishers.noBody()));
    
        request.headers().map().forEach((key, values) -> {
            for (String value : values) {
                builder.header(key, value);
            }
        });
        builder.header("x-request-meta", generateRequestMeta(RECIPIENT_ID));
        return builder.build();
    }
}