add rpc.sh wrapper script for calling JSON RPC

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

tasks/config.yml

@@ -10,7 +10,7 @@
     - '{{ beacon_node_cont_vol }}/data'
     - '{{ beacon_node_secrets_path }}'
 
-- name: 'Create netkey file (optional)'
+- name: Create netkey file (optional)
   copy:
     dest: '{{ beacon_node_cont_vol  }}/{{ beacon_node_netkey_cont_path }}'
     content: '{{ beacon_node_netkey }}'
@@ -19,7 +19,14 @@
     mode: 0600
   when: beacon_node_netkey is defined
 
+- name: Create JSON RPC wrapper script
+  template:
+    src: 'rpc.sh.j2'
+    dest: '{{ beacon_node_cont_vol }}/rpc.sh'
+    owner: 'root'
+    group: 'docker'
+    mode: 0750
+
 - name: Verify network name
   assert:
     that: '{{ beacon_node_network in ["toledo", "pyrmont", "prater", "mainnet"] }}'
-

templates/rpc.sh.j2

@@ -0,0 +1,31 @@
+#!/usr/bin/env bash
+# vim: set ft=sh:
+
+URL="http://localhost:{{ beacon_node_rpc_port }}/"
+
+METHOD="$1"
+shift
+PARAMS=("$@")
+
+if [[ -z "${METHOD}" ]]; then
+    echo "No method specified!" >&2
+    exit 1
+fi
+if [[ -n "${PARAMS}" ]]; then
+    PARAMS_STR=$(printf '%s\",\"' "${PARAMS[@]}")
+    PARAMS_STR="\"${PARAMS_STR%%\",\"}\""
+else
+    PARAMS_STR=''
+fi
+
+PAYLOAD="{
+  \"id\": 1,
+  \"jsonrpc\": \"2.0\",
+  \"method\": \"${METHOD}\",
+  \"params\": [${PARAMS_STR}]
+}"
+
+curl -s -X POST \
+    -H "Content-type:application/json" \
+    --data "${PAYLOAD}" \
+    "${URL}" | jq .