bug: discovery not effect because of additional properties rewrite to etcd

[Monstergogo]

1. add a new upstream in apisix dashboard as follow before start apisix-seed, config preview like this:
   { "timeout": { "connect": 6, "send": 6, "read": 6 }, "type": "roundrobin", "scheme": "grpc", "discovery_type": "nacos", "pass_host": "pass", "name": "apisix-seed", "service_name": "share.ShareService", "keepalive_pool": { "idle_timeout": 60, "requests": 1000, "size": 320 } }
2. start apisix-seed with nacos as discovery， apisix-seed will rewrite nodes to etcd, and i get upstream config like this:
   { "_discovery_type": "nacos", "_service_name": "share.ShareService", "create_time": 1699364548, "id": "486262354254758591", "keepalive_pool": { "idle_timeout": 60, "requests": 1000, "size": 320 }, "name": "apisix-seed", "nodes": [ { "host": "10.66.36.202", "port": 5018, "weight": 10 } ], "pass_host": "pass", "scheme": "grpc", "timeout": { "connect": 6, "read": 6, "send": 6 }, "type": "roundrobin", "update_time": 1699364548 }

it added field “_discovery_type” and "_service_name" which caused apisix err:
[error] 51#51: *251621 [lua] config_etcd.lua:843: failed to fetch data from etcd: failed to check item data of [/apisix/upstreams] err:additional properties forbidden, found _discovery_type, etcd key: /apisix/upstreams, context: ngx.timer

apisix version: 3.6.0

[Monstergogo]

i read the code and find delete filed DiscoveryType and ServiceName directly can fix it. just delete one line code in internal/core/message/a6conf.go: line 106

[monkeyDluffy6017]

Would you like to fix this?

[Monstergogo]

Would you like to fix this?

pull request created

[Monstergogo]

Would you like to fix this?

lol, I encountered other issues when fixing this issue. it's fine when work with apisix version: 3.5.0 and below, upstream in apisix 3.6.0 not allowed additional properties like _discovery_type, but it's necessary to save properties like _discovery_type: need to know discovery type when apisix-seed restart.

[monkeyDluffy6017]

@Monstergogo If you think the _discovery_type is necessary, you could post a pr to add it in apisix