add rpc.sh script for easier JSON RPC calls

Signed-off-by: Jakub Sokołowski <jakub@status.im>

defaults/main.yml

@@ -6,6 +6,7 @@ beacon_node_service_home: 'C:\Users\{{ beacon_node_service_user_name }}'
 beacon_node_service_path: '{{ beacon_node_service_home }}\{{ beacon_node_service_name }}'
 beacon_node_service_bin_path: '{{ beacon_node_service_path }}\bin'
 beacon_node_service_exe: '{{ beacon_node_service_bin_path }}\nimbus_beacon_node.exe'
+beacon_node_rpc_script_path: '{{ beacon_node_service_path }}\rpc.sh'
 
 beacon_node_repo_url: 'https://github.com/status-im/nimbus-eth2.git'
 beacon_node_repo_branch: 'stable'

tasks/config.yml

@@ -0,0 +1,5 @@
+---
+- name: Create JSON RPC wrapper script
+  win_template:
+    src: 'rpc.sh.j2'
+    dest: '{{ beacon_node_rpc_script_path }}'

tasks/main.yml

@@ -3,6 +3,7 @@
 - import_tasks: user.yml
 - import_tasks: install.yml
 - import_tasks: build.yml
+- import_tasks: config.yml
 - import_tasks: service.yml
 - import_tasks: validators.yml
   when: beacon_node_dist_validators_enabled

templates/rpc.sh.j2

@@ -0,0 +1,33 @@
+#!/usr/bin/env bash
+# vim: set ft=sh:
+set -euo pipefail
+
+URL="http://localhost:{{ beacon_node_rpc_port }}/"
+
+METHOD="$1"
+shift
+
+if [[ -z "${METHOD}" ]]; then
+    echo "No method specified!" >&2
+    exit 1
+fi
+if [[ -n "${@}" ]]; then
+    PARAMS=$(printf '%s,' "${@}")
+    PARAMS="${@%%,}\""
+else
+    PARAMS=''
+fi
+
+PAYLOAD="{
+  \"id\": 1,
+  \"jsonrpc\": \"2.0\",
+  \"method\": \"${METHOD}\",
+  \"params\": [${PARAMS}]
+}"
+
+# The jq script checks if error exists and adjusts exit code.
+curl -s -X POST --max-time 10 \
+    -H "Content-type:application/json" \
+    --data "${PAYLOAD}" \
+    "${URL}" | \
+     jq -e '., if .error != null then null|halt_error(2) else halt end'