Chore: Add DummyEL

Author: kevaundray

Cargo.lock

@@ -65,6 +65,7 @@ members = [
     "crypto/eth2_wallet",
     "crypto/kzg",
     "database_manager",
+    "dummy_el",
     "lcli",
     "lighthouse",
     "lighthouse/environment",

Cargo.toml

@@ -0,0 +1,20 @@
+[package]
+name = "dummy_el"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+axum = { workspace = true }
+serde = { workspace = true }
+serde_json = { workspace = true }
+tokio = { workspace = true }
+tracing = { workspace = true }
+tracing-subscriber = { workspace = true, features = ["env-filter", "json"] }
+clap = { workspace = true }
+anyhow = { workspace = true }
+jsonwebtoken = "9"
+hex = { workspace = true }
+
+[[bin]]
+name = "dummy_el"
+path = "src/main.rs"

dummy_el/Cargo.toml

@@ -0,0 +1,32 @@
+# Multi-stage build for dummy_el
+FROM rust:1.88.0-bullseye AS builder
+
+WORKDIR /build
+
+# Copy the entire workspace (needed for workspace structure)
+COPY . .
+
+# Build only dummy_el in release mode
+RUN --mount=type=cache,target=/usr/local/cargo/registry \
+    --mount=type=cache,target=/build/target \
+    cargo build --release -p dummy_el && \
+    cp target/release/dummy_el /dummy_el
+
+# Runtime stage with minimal Ubuntu image
+FROM ubuntu:22.04
+
+RUN apt-get update && apt-get -y upgrade && apt-get install -y --no-install-recommends \
+  ca-certificates \
+  && apt-get clean \
+  && rm -rf /var/lib/apt/lists/*
+
+# Copy the binary from builder
+COPY --from=builder /dummy_el /usr/local/bin/dummy_el
+
+# Create a fake 'geth' binary that runs dummy_el instead
+# Kurtosis will call "geth init ..." and "geth --..." but we'll run dummy_el
+COPY --from=builder /build/dummy_el/geth-wrapper.sh /usr/local/bin/geth
+RUN chmod +x /usr/local/bin/geth
+
+# Expose default Engine API port
+EXPOSE 8551

dummy_el/Dockerfile

@@ -0,0 +1,24 @@
+# Using Dummy EL
+
+This is a dummy EL that can be used with proof verification nodes. These nodes do not require an EL to function since they just take in proofs. 
+
+## Quick Start
+
+### 1. Build the Docker Image
+
+From the lighthouse repository root:
+
+```bash
+docker build -f dummy_el/Dockerfile -t dummy_el:local .
+```
+
+### 2. Adding to Kurtosis
+
+In Kurtosis, you can add the following:
+
+```yaml
+  - el_type: geth
+    el_image: dummy_el:local
+```
+
+Note that we need to use el_type `geth` as kurtosis will be looking for a binary named geth. We wrap calls to the Geth binary so that they are processed by our dummy_el.

dummy_el/README.md

@@ -0,0 +1,29 @@
+#!/bin/sh
+set -e
+
+# This is a wrapper that pretends to be geth but actually runs dummy_el
+# Kurtosis calls: geth init ... && geth --authrpc.port=8551 ...
+# We ignore the init, and when we see the actual geth command with authrpc.port, we start dummy_el
+
+echo "[dummy_el geth-wrapper] Called with: $@"
+
+# Check if this is the "geth init" command and ignore it
+if echo "$@" | grep -q "init"; then
+    echo "[dummy_el geth-wrapper] Ignoring 'geth init' command"
+    exit 0
+fi
+
+# If we're here, it's the actual geth run command
+# Kurtosis mounts JWT secret at /jwt/jwtsecret
+JWT_PATH="/jwt/jwtsecret"
+
+echo "[dummy_el geth-wrapper] Starting dummy_el instead of geth"
+
+# Run dummy_el with JWT if available, otherwise without
+if [ -f "$JWT_PATH" ]; then
+    echo "[dummy_el geth-wrapper] Using JWT from $JWT_PATH"
+    exec /usr/local/bin/dummy_el --host 0.0.0.0 --port 8551 --jwt-secret "$JWT_PATH"
+else
+    echo "[dummy_el geth-wrapper] WARNING: No JWT file found at $JWT_PATH"
+    exec /usr/local/bin/dummy_el --host 0.0.0.0 --port 8551
+fi