Dynamic Domain Name Implementation in Mobile Apps

This article describes how to implement dynamic domain name switching in mobile applications to handle DNS resolution issues in certain regions. The solution combines a configuration center platform with native network interception techniques.

iOS Implementation: Uses NSURLProtocol, an abstract class provided by Apple for handling protocol-specific URL data. By creating a custom subclass and registering it with registerClass: , developers can intercept all HTTP/HTTPS requests. Key methods include canInitWithRequest: to determine which requests to intercept, canonicalRequestForRequest: for request customization, and startLoading / stopLoading for managing the request lifecycle. For third-party libraries like AFNetworking and Alamofire, Method Swizzle is used to replace protocolClasses in NSURLSessionConfiguration.

Android Implementation: Uses OkHttp and HttpUrlConnection/HttpsUrlConnection interception through bytecode instrumentation. The approach involves intercepting OkHttpClient configuration and URLConnection parameters to dynamically replace domain names.

Flutter Implementation: Uses external textures (TextureLayer) to bridge Flutter with native image loading. By leveraging PixelBuffer as the data carrier between Native and Flutter, image loading is delegated to native libraries like SDWebImage, enabling dynamic domain name support for images while regular network requests use Flutter plugins that call native libraries.

H5 Implementation: Uses frontend configuration to dynamically switch domains when domain access anomalies are detected, combined with the configuration center for unified network request management.

The solution can also be extended to: statistics network interface failure rates, redirect network requests, add common headers to requests, and return custom responses.