Converting v2ray json config (client side) into V2RayN style subscription links

convert_to_v2rayn_sub.sh

#!/bin/bash

# brew install jq
# brew install qrencode

config_file=v2rayx*.json
rss_file=rss.txt

cat $config_file | \
  jq -r '
    def user: .settings.vnext[0].users[0];
    def vnext: .settings.vnext[0];

    def header_host:
      (.streamSettings.wsSettings.headers // {}) as $h |
      ($h | to_entries | map(select(.key|ascii_downcase == "host")) | .[0]?.value // "");

    def net:
      .streamSettings.network // "tcp";

    def type:
      if net == "tcp" then
        (.streamSettings.tcpSettings.header.type // "none")
      elif net == "kcp" then
        (.streamSettings.kcpSettings.header.type // "none")
      elif net == "quic" then
        (.streamSettings.quicSettings.security // "none")
      else
        "none"
      end;

    def host:
      if net == "ws" then
        header_host
      elif net == "http" then
        ((.streamSettings.tcpSettings.header.request.headers.Host // []) | join(","))
      elif net == "h2" then
        (.streamSettings.httpSettings.host[0] // "")
      else
        ""
      end;

    def path:
      if net == "ws" then
        (.streamSettings.wsSettings.path // "")
      elif net == "h2" then
        (.streamSettings.httpSettings.path // "")
      elif net == "quic" then
        (.streamSettings.quicSettings.key // "")
      elif net == "kcp" then
        (.streamSettings.kcpSettings.seed // "")
      elif net == "grpc" then
        (.streamSettings.grpcSettings.serviceName // "")
      else
        ""
      end;

    def tls:
      if .streamSettings.security == "tls" then "tls" else "" end;

    def sni:
      if .streamSettings.security == "tls" then
        (.streamSettings.tlsSettings.serverName // "")
      else
        ""
      end;

    def alpn:
      if .streamSettings.security == "tls" then
        ((.streamSettings.tlsSettings.alpn // []) | join(","))
      else
        ""
      end;

    def fp:
      (.streamSettings.tlsSettings.fingerprint // "");

    .outbounds
    | map(select(.protocol == "vmess"))
    | .[]
    | {
        v: "2",
        ps: (.tag // ""),
        add: (vnext.address // ""),
        port: ((vnext.port // "") | tostring),
        id: (user.id // ""),
        aid: ((user.alterId // 0) | tostring),
        scy: (user.security // "auto"),
        net: net,
        type: type,
        host: host,
        path: path,
        tls: tls,
        sni: sni,
        alpn: alpn,
        fp: fp
      }
    | "vmess://"
      + (@json | @base64)
  ' | \
  base64 > "$rss_file"

# put $rss_file to somewhere, then your qr code for the subscribe link is
rss_url="https://yourserver/rss.txt"
qrencode -t ANSI "$(echo -n "sub://$(echo -n "$rss_url" | base64)")"