Set Flapdoodle’s Download Proxy Before MongoDB Starts

Customize DownloadPackage in a transition-based Flapdoodle setup, and remember that a warm cache can skip the proxy path.

If startup fails while fetching the MongoDB archive, configure Flapdoodle's package downloader. The HTTP proxy list can supply candidate endpoints for a public download route. The database client has not yet made its later connection.

The modern transition-based customization supplies the proxy through DownloadPackage:

Mongod mongod = new Mongod() {
    @Override
    public DownloadPackage downloadPackage() {
        return DownloadPackage.withDefaults()
            .withDownloadConfig(DownloadConfig.defaults()
                .withProxyFactory(() -> Proxys.httpProxy("proxy.example", 8080)));
    }
};

Use the classes from the selected Flapdoodle MongoDB and embedded-process libraries, then use this customized Mongod in the application or test setup. The lambda supplies the HTTP proxy; the archive URL remains the download destination.

A successful cached start does not exercise that proxy. The package transition checks the download cache first, so distinguish a cache hit from an actual archive fetch when evaluating the startup result.

This pattern belongs to the transition API. Older RuntimeConfig builders and Spring Boot's former DownloadConfigBuilderCustomizer use different customization and cache-layout interfaces; match the example to the dependency generation in the application.

Erthyglow kevrennek