Add script for creating keystores folder

README.md

@@ -71,6 +71,41 @@ You can use `eth-staking-smith` as follows to convert your address:
 
 Note that --validator-index and --validator-start-index are two distinct parameter, the former being index of validator on Beacon chain, and the latter is the index of validator private key derived from the seed
 
+## Exporting CLI standard output into common keystores folder format
+
+Most validator clients recognize the keystore folder format,
+produced by upstream Python deposit CLI. While `eth-staking-smith` outputs
+all validator data into standard output, allowing for better security in
+enterprise setups, for small and individual stakers this is not convenient,
+as they need to be able to import validator keys directly into validator client.
+
+To address such needs, `eth-staking-smith` provides convenience Python3 script
+to export JSON validator output into common keystore folder format. It should
+work on any box with Python 3.10+ installed.
+
+```
+mkdir validator_keys/
+./target/debug/eth-staking-smith new-mnemonic --chain holesky --num_validators 2 \
+  --keystore_password test > validator_secrets.json
+cat validator_secrets.json | python3 scripts/generate_keys_folder.py
+cat validator_secrets.json | jq .mnemonic.seed > mnemonic.txt
+rm validator_secrets.json
+echo "MAKE SURE TO BACK UP mnemonic.text IN THE SAFE PLACE"
+
+ls validator_keys/
+deposit_data-1720014619.json  keystore-m_12381_3600_0_0_0-1720014619.json  keystore-m_12381_3600_1_0_0-1720014619.json
+```
+
+The contents of `validator_keys/` folder might be imported into most
+validator clients, for example Lighthouse import command will look like that:
+
+```
+echo "test" > ./password.txt
+lighthouse account validator import \
+  --network holesky --reuse-password
+  --directory validator_keys/ --password-file ./password.txt
+```
+
 ### Command to send SignedBLSToExecutionChange request to Beacon node
 
 ```

scripts/generate_keys_folder.py

@@ -0,0 +1,69 @@
+#!/usr/bin/env python3
+
+#
+# This script takes JSON output of `eth-staking-smith` into stdin,
+# and produces folder with deposit data and keystore files in the given
+# location.
+#
+# Caveat: keystore_password should be specified before generating.
+#
+
+import argparse
+import json
+import logging
+import pathlib
+import sys
+import time
+
+
+logger = logging.getLogger(__name__)
+parser = argparse.ArgumentParser("Generate eth validator keys folder")
+parser.add_argument(
+    "output_folder",
+    default=pathlib.Path("validator_keys/"),
+    nargs="?",
+    help="Folder where to store deposit data",
+)
+
+
+def main():
+    args = parser.parse_args()
+    base_path = args.output_folder
+    if type(base_path) == str:
+        base_path = pathlib.Path(base_path)
+    assert base_path.exists(), "Output folder must exist"
+    inp = sys.stdin.read()
+    assert inp, "Should have value at standard input"
+    try:
+        validators = json.loads(inp)
+    except (KeyError, ValueError) as exc:
+        logger.exception("Got invalid json input")
+    else:
+        assert validators, "Should have non-empty JSON value passed"
+        assert (
+            "keystores" in validators
+        ), "Should have non-empty keystores in eth-staking-smith output"
+        deposit_datas = validators["deposit_data"]
+        num_validators = len(deposit_datas)
+        print(f"Exporting {num_validators} keystores to {base_path}")
+        # Set path as EIP-2334 format
+        # https://eips.ethereum.org/EIPS/eip-2334
+        for idx, keystore in enumerate(validators["keystores"]):
+            ts = int(time.time())
+            purpose = "12381"
+            coin_type = "3600"
+            account = str(idx)
+            withdrawal_key_path = f"m/{purpose}/{coin_type}/{account}/0"
+            signing_key_path = f"{withdrawal_key_path}/0"
+            file_path = signing_key_path.replace("/", "_")
+            filename = f"keystore-{file_path}-{ts}.json"
+            with open(base_path / filename, "w") as fl:
+                fl.write(json.dumps(keystore))
+
+        with open(base_path / f"deposit_data-{ts}.json", "w") as fl:
+            fl.write(json.dumps(deposit_datas))
+
+
+if __name__ == "__main__":
+    logging.basicConfig(stream=sys.stdout, level=logging.WARN)
+    main()