added scripts to start a test network

.gitignore

@@ -1,2 +1,3 @@
 /target
+build
 detee_challenge_nodes

scripts/Dockerfile

@@ -0,0 +1,4 @@
+FROM alpine:edge
+COPY start.sh /start.sh
+COPY hacker-challenge /hacker-challenge
+ENTRYPOINT ["/start.sh"]

scripts/start.sh

@@ -0,0 +1,8 @@
+#!/bin/sh
+
+# This script start the hacker challenge from within the docker container.
+# It's only purpose is to help bootstrap a test network.
+
+echo $INIT_NODES > /detee_challenge_nodes
+
+/hacker-challenge

scripts/testnet.sh

@@ -0,0 +1,21 @@
+#!/bin/bash
+cd "$(dirname "$0")"/..
+set -e
+cargo build --release --target x86_64-unknown-linux-musl
+rm -rf build
+mkdir -p build
+cp ./target/x86_64-unknown-linux-musl/release/hacker-challenge build/
+cp scripts/start.sh build/
+cp scripts/Dockerfile build/
+cd build
+
+docker build -t hacker-challenge:latest .
+
+docker ps -a | grep 'hacker-challenge' | awk '{ print $NF }' | xargs docker rm -f || true
+
+for i in {0..10}
+do
+  docker run -d --name "hacker-challenge_$i" \
+    --env INIT_NODES="172.17.0.2 172.17.0.3 172.17.0.4" \
+    hacker-challenge:latest
+done

src/datastore.rs

@@ -250,6 +250,9 @@ impl Store {
         use rand::RngCore;
         let nodes = self.nodes.lock().await;
         let len = nodes.len();
+        if len == 0 {
+            return Vec::new();
+        }
         let skip = OsRng.next_u64().try_into().unwrap_or(0) % len;
         let mut iter = nodes.iter().cycle().skip(skip);
         let mut random_nodes = vec![];

src/grpc/client.rs

@@ -27,7 +27,7 @@ impl ConnManager {
     }
 
     async fn connect(self, node_ip: String) {
-        let mut client = UpdateClient::connect(format!("http://{node_ip}:50051"))
+        let mut client = UpdateClient::connect(format!("{node_ip}:31373"))
             .await
             .unwrap();