feat(apisix): add Cloudron package

- Implements Apache APISIX packaging for Cloudron platform.
- Includes Dockerfile, CloudronManifest.json, and start.sh.
- Configured to use Cloudron's etcd addon.

🤖 Generated with Gemini CLI
Co-Authored-By: Gemini <noreply@google.com>

CloudronPackages/APISIX/apisix-source/apisix/discovery/dns/init.lua

@@ -0,0 +1,89 @@
+--
+-- Licensed to the Apache Software Foundation (ASF) under one or more
+-- contributor license agreements.  See the NOTICE file distributed with
+-- this work for additional information regarding copyright ownership.
+-- The ASF licenses this file to You under the Apache License, Version 2.0
+-- (the "License"); you may not use this file except in compliance with
+-- the License.  You may obtain a copy of the License at
+--
+--     http://www.apache.org/licenses/LICENSE-2.0
+--
+-- Unless required by applicable law or agreed to in writing, software
+-- distributed under the License is distributed on an "AS IS" BASIS,
+-- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+-- See the License for the specific language governing permissions and
+-- limitations under the License.
+--
+
+local core          = require("apisix.core")
+local config_local  = require("apisix.core.config_local")
+local is_http       = ngx.config.subsystem == "http"
+local ipairs        = ipairs
+local error         = error
+
+
+local dns_client
+local _M = {}
+
+
+function _M.nodes(service_name)
+    local host, port = core.utils.parse_addr(service_name)
+    core.log.info("discovery dns with host ", host, ", port ", port)
+
+    local records, err = dns_client:resolve(host, core.dns_client.RETURN_ALL)
+    if not records then
+        return nil, err
+    end
+
+    local nodes = core.table.new(#records, 0)
+    local index = 1
+    for _, r in ipairs(records) do
+        if r.address then
+            local node_port = port
+            if not node_port and r.port ~= 0 then
+                -- if the port is zero, fallback to use the default
+                node_port = r.port
+            end
+
+            -- ignore zero port when subsystem is stream
+            if node_port or is_http then
+                nodes[index] = {host = r.address, weight = r.weight or 1, port = node_port}
+                if r.priority then
+                    -- for SRV record, nodes with lower priority are chosen first
+                    nodes[index].priority = -r.priority
+                end
+                index = index + 1
+            end
+        end
+    end
+
+    return nodes
+end
+
+
+function _M.init_worker()
+    local local_conf = config_local.local_conf()
+    local servers = local_conf.discovery.dns.servers
+    local resolv_conf = local_conf.discovery.dns.resolv_conf
+    local default_order = {"last", "SRV", "A", "AAAA", "CNAME"}
+    local order = core.table.try_read_attr(local_conf, "discovery", "dns", "order")
+    order = order or default_order
+
+    local opts = {
+        hosts = {},
+        resolvConf = resolv_conf,
+        nameservers = servers,
+        order = order,
+    }
+
+    local client, err = core.dns_client.new(opts)
+    if not client then
+        error("failed to init the dns client: ", err)
+        return
+    end
+
+    dns_client = client
+end
+
+
+return _M