From f377ae1fdba6553446e88129d0b05f8345e3bc4f Mon Sep 17 00:00:00 2001
From: Denis Kadyshev <metajiji@gmail.com>
Date: Mon, 13 Jan 2025 18:46:59 +0700
Subject: [PATCH 1/3] Update Dockerfile-dnsdist

---
 Dockerfile-dnsdist | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/Dockerfile-dnsdist b/Dockerfile-dnsdist
index d303c2be1e2b..100b0d617bef 100644
--- a/Dockerfile-dnsdist
+++ b/Dockerfile-dnsdist
@@ -91,10 +91,9 @@ FROM debian:12-slim
 RUN apt-get update && apt-get -y dist-upgrade && apt-get clean
 
 # - python3 and jinja2 (for startup script)
-# - python3-atomicwrites (for backend management)
 # - tini (for signal management)
 # - ca-certificates (for verifying downstream DoH/DoT certificates)
-RUN apt-get install -y python3 python3-jinja2 python3-atomicwrites tini libcap2-bin ca-certificates && apt-get clean
+RUN apt-get install -y python3 python3-jinja2 tini libcap2-bin ca-certificates && apt-get clean
 
 # Output from builder
 COPY --from=builder /build /
@@ -126,6 +125,5 @@ EXPOSE 8083/tcp
 WORKDIR /etc/dnsdist
 
 COPY dockerdata/dnsdist-resolver.lua /etc/dnsdist/
-COPY dockerdata/dnsdist-resolver.py /usr/local/bin/dnsdist-resolver
 
 ENTRYPOINT ["/usr/bin/tini", "--", "/usr/local/bin/dnsdist-startup"]

From fa27c7247dfeb7085bedffcc7e1085318d0aa187 Mon Sep 17 00:00:00 2001
From: Denis Kadyshev <metajiji@gmail.com>
Date: Mon, 13 Jan 2025 18:48:41 +0700
Subject: [PATCH 2/3] Delete dockerdata/dnsdist-resolver.py

---
 dockerdata/dnsdist-resolver.py | 43 ----------------------------------
 1 file changed, 43 deletions(-)
 delete mode 100755 dockerdata/dnsdist-resolver.py

diff --git a/dockerdata/dnsdist-resolver.py b/dockerdata/dnsdist-resolver.py
deleted file mode 100755
index 152298d61635..000000000000
--- a/dockerdata/dnsdist-resolver.py
+++ /dev/null
@@ -1,43 +0,0 @@
-#!/usr/bin/env python3
-import socket
-import sys
-import threading
-import time
-
-from atomicwrites import atomic_write
-
-class LookupThread(threading.Thread):
-    def run(self):
-        while True:
-            ips = dict()
-            for target in self.targets:
-                addrs = ips.get(target, [])
-
-                try:
-                    res = socket.getaddrinfo(target, 0, proto=socket.IPPROTO_UDP)
-                    addrs = [item[4][0] for item in res]
-                except socket.gaierror as e:
-                    if e.errno in (socket.EAI_NODATA, socket.EAI_NONAME):
-                        addrs = []
-
-                ips[target] = addrs
-
-            with atomic_write(self.fname, overwrite=True) as out:
-                out.write('return {\n')
-                for name,addrs in ips.items():
-                    out.write('  ["{}"]='.format(name) + '{\n')
-                    for addr in addrs:
-                        out.write('    "{}",\n'.format(addr))
-                    out.write('  },\n')
-                out.write('}\n')
-
-            time.sleep(1)
-
-if __name__ == '__main__':
-    lt = LookupThread()
-    lt.setDaemon(True)
-    lt.targets = []
-    lt.fname = '/tmp/dnsdist-resolver.out'
-    lt.start()
-    for line in sys.stdin:
-        lt.targets=line.split()

From ab5fabef3dfb39d3a7dad1a497fe5fa67a370e22 Mon Sep 17 00:00:00 2001
From: Denis Kadyshev <metajiji@gmail.com>
Date: Mon, 13 Jan 2025 18:54:35 +0700
Subject: [PATCH 3/3] Update dnsdist-resolver.lua

---
 dockerdata/dnsdist-resolver.lua | 25 ++++++++++---------------
 1 file changed, 10 insertions(+), 15 deletions(-)

diff --git a/dockerdata/dnsdist-resolver.lua b/dockerdata/dnsdist-resolver.lua
index 89e24b319e6e..f9bf8d1c3c04 100644
--- a/dockerdata/dnsdist-resolver.lua
+++ b/dockerdata/dnsdist-resolver.lua
@@ -17,7 +17,15 @@ _M.verbose = false
 local ourservers = {}
 local ourcount = {}
 
-local resolverpipe = io.popen('/usr/local/bin/dnsdist-resolver', 'w')
+-- Global variable for store results for getAddressInfo() function
+local resout = {}
+
+local function resolveCB(hostname, ips)
+    resout[hostname] = {}
+    for _, ip in ipairs(ips) do
+        table.insert(resout[hostname], ip:toString())
+    end
+end
 
 local function tablecopy(t)
     local t2 = {}
@@ -71,22 +79,9 @@ local function setServer(name, ip)
 end
 
 function _M.maintenance()
-    -- TODO: only do this if the list has changed
-    -- TODO: check return values
     for k in pairs(_M.servers) do
-        resolverpipe:write(k .. ' ')
+        getAddressInfo(k, resolveCB)
     end
-    resolverpipe:write('\n')
-    resolverpipe:flush()
-
-    -- TODO: maybe this failure should be quiet for the first X seconds?
-    local ret, resout = pcall(loadfile, '/tmp/dnsdist-resolver.out')
-    if not ret then
-        error(resout)
-    end
-
-    -- on purpose no pcall, an error here is a bug
-    resout = resout()
 
     local activeservers = {}
     -- check for servers removed by controller