p2p: add network simulation framework (#14982)

This commit introduces a network simulation framework which
can be used to run simulated networks of devp2p nodes. The
intention is to use this for testing protocols, performing
benchmarks and visualising emergent network behaviour.

1 files changed, 40 insertions, 0 deletions

diff --git a/p2p/simulations/examples/ping-pong.sh b/p2p/simulations/examples/ping-pong.sh
new file mode 100755
index 000000000..47936bd9a
--- /dev/null
+++ b/p2p/simulations/examples/ping-pong.sh
@@ -0,0 +1,40 @@
+#!/bin/bash
+#
+# Boot a ping-pong network simulation using the HTTP API started by ping-pong.go
+
+set -e
+
+main() {
+  if ! which p2psim &>/dev/null; then
+    fail "missing p2psim binary (you need to build cmd/p2psim and put it in \$PATH)"
+  fi
+
+  info "creating 10 nodes"
+  for i in $(seq 1 10); do
+    p2psim node create --name "$(node_name $i)"
+    p2psim node start "$(node_name $i)"
+  done
+
+  info "connecting node01 to all other nodes"
+  for i in $(seq 2 10); do
+    p2psim node connect "node01" "$(node_name $i)"
+  done
+
+  info "done"
+}
+
+node_name() {
+  local num=$1
+  echo "node$(printf '%02d' $num)"
+}
+
+info() {
+  echo -e "\033[1;32m---> $(date +%H:%M:%S) ${@}\033[0m"
+}
+
+fail() {
+  echo -e "\033[1;31mERROR: ${@}\033[0m" >&2
+  exit 1
+}
+
+main "$@"