feat: support configuring the order of the upstream dns service discovery resolve

apisix/core/config_local.lua

@@ -21,6 +21,7 @@
 
 local file = require("apisix.cli.file")
 local schema = require("apisix.cli.schema")
+local util = require("apisix.cli.util")
 
 
 local _M = {}
@@ -65,7 +66,10 @@ function _M.local_conf(force)
     end
 
     -- fill the default value by the schema
-    schema.validate(default_conf)
+    local ok, err = schema.validate(default_conf)
+    if not ok then
+        error(err)
+    end
 
     config_data = default_conf
     return config_data

apisix/discovery/dns/init.lua

@@ -59,11 +59,15 @@ function _M.init_worker()
     local local_conf = config_local.local_conf()
     local servers = local_conf.discovery.dns.servers
 
+    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 = {},
         nameservers = servers,
-        order = {"last", "SRV", "A", "AAAA", "CNAME"},
+        order = order,
     }
 
     local client, err = core.dns_client.new(opts)

apisix/discovery/dns/schema.lua

@@ -24,6 +24,15 @@ return {
                 type = "string",
             },
         },
+        order = {
+            type = "array",
+            minItems = 1,
+            maxItems = 5,
+            uniqueItems = true,
+            items = {
+                enum = {"last", "SRV", "A", "AAAA", "CNAME"}
+            },
+        },
     },
     required = {"servers"}
 }

conf/config-default.yaml

@@ -258,6 +258,12 @@ nginx_config:                     # config for render the template to generate n
 #  dns:
 #    servers:
 #      - "127.0.0.1:8600"         # use the real address of your dns server
+#    order:                       # order in which to try different dns record types when resolving
+#      - last                     # "last" will try the last previously successful type for a hostname.
+#      - SRV
+#      - A
+#      - AAAA
+#      - CNAME
 #  eureka:
 #    host:                        # it's possible to define multiple eureka hosts addresses of the same eureka cluster.
 #      - "http://127.0.0.1:8761"

t/discovery/dns/sanity.t

@@ -120,6 +120,10 @@ upstreams:
       id: 1
 --- response_body
 hello world
+--- grep_error_log eval
+qr/proxy request to \S+/
+--- grep_error_log_out
+proxy request to [0:0:0:0:0:0:0:1]:1980
 
 
 
@@ -133,6 +137,10 @@ upstreams:
       id: 1
 --- response_body
 hello world
+--- grep_error_log eval
+qr/proxy request to \S+/
+--- grep_error_log_out
+proxy request to 127.0.0.1:1980
 
 
 
@@ -318,3 +326,115 @@ qr/upstream nodes: \{[^}]+\}/
 qr/upstream nodes: \{("127.0.0.1:1980":60,"127.0.0.2:1980":20|"127.0.0.2:1980":20,"127.0.0.1:1980":60)\}/
 --- response_body
 hello world
+
+
+
+=== TEST 16: prefer A than SRV when A is ahead of SRV in config.yaml
+--- yaml_config
+apisix:
+    node_listen: 1984
+    enable_admin: false
+deployment:
+    role: data_plane
+    role_data_plane:
+        config_provider: yaml
+discovery:
+    dns:
+        servers:
+            - "127.0.0.1:1053"
+        order:
+            - A
+            - SRV
+--- apisix_yaml
+upstreams:
+    - service_name: "srv-a.test.local"
+      discovery_type: dns
+      type: roundrobin
+      id: 1
+--- error_code: 502
+--- error_log
+proxy request to 127.0.0.1:80
+
+
+
+=== TEST 17: Invalid order type in config.yaml
+--- yaml_config
+apisix:
+    node_listen: 1984
+    enable_admin: false
+deployment:
+    role: data_plane
+    role_data_plane:
+        config_provider: yaml
+discovery:
+    dns:
+        servers:
+            - "127.0.0.1:1053"
+        order:
+            - B
+            - SRV
+--- apisix_yaml
+upstreams:
+    - service_name: "srv-a.test.local"
+      discovery_type: dns
+      type: roundrobin
+      id: 1
+--- must_die
+--- error_log
+matches none of the enum values
+
+
+
+=== TEST 18: Multiple order type in config.yaml
+--- yaml_config
+apisix:
+    node_listen: 1984
+    enable_admin: false
+deployment:
+    role: data_plane
+    role_data_plane:
+        config_provider: yaml
+discovery:
+    dns:
+        servers:
+            - "127.0.0.1:1053"
+        order:
+            - SRV
+            - SRV
+--- apisix_yaml
+upstreams:
+    - service_name: "srv-a.test.local"
+      discovery_type: dns
+      type: roundrobin
+      id: 1
+--- must_die
+--- error_log
+expected unique items but items 1 and 2 are equal
+
+
+
+=== TEST 19: invalid order type in config.yaml
+--- yaml_config
+apisix:
+    node_listen: 1984
+    enable_admin: false
+deployment:
+    role: data_plane
+    role_data_plane:
+        config_provider: yaml
+discovery:
+    dns:
+        servers:
+            - "127.0.0.1:1053"
+        order:
+            - a
+            - SRV
+--- apisix_yaml
+upstreams:
+    - service_name: "srv-a.test.local"
+      discovery_type: dns
+      type: roundrobin
+      id: 1
+--- must_die
+--- error_log
+matches none of the enum values

t/plugin/redirect.t

@@ -477,8 +477,8 @@ apisix:
     ssl:
         enable: true
         listen:
-            - 6443
-            - 7443
+            - port: 6443
+            - port: 7443
             - port: 8443
             - port: 9443
 --- request