Add keystore export flag to VC

validator_client/src/cli.rs

@@ -188,6 +188,18 @@ pub fn cli_app<'a, 'b>() -> App<'a, 'b> {
                     address of this server (e.g., http://localhost:5062).")
                 .takes_value(true),
         )
+        .arg(
+            Arg::with_name("http-allow-keystore-export")
+                .long("http-allow-keystore-export")
+                .value_name("ORIGIN")
+                .help("If present, allow access to the DELETE /lighthouse/keystores HTTP \
+                    API method, which allows exporting keystores and passwords to HTTP API \
+                    consumers who have access to the API token. This method is useful for \
+                    exporting validators, however it should be used with caution since it \
+                    exposes private key data to authorized users.")
+                .required(false)
+                .takes_value(false),
+        )
         /* Prometheus metrics HTTP server related arguments */
         .arg(
             Arg::with_name("metrics")

validator_client/src/config.rs

@@ -255,6 +255,10 @@ impl Config {
             config.http_api.allow_origin = Some(allow_origin.to_string());
         }
 
+        if cli_args.is_present("http-allow-keystore-export") {
+            config.http_api.allow_keystore_export = true;
+        }
+
         /*
          * Prometheus metrics HTTP server
          */