chore(router) deprecate setting path handling v1 when router_flavor is traditional_compatible

[windmgc]

Summary

This PR denies users from setting path_handling=v1 when the Kong gateway is running with router_flavor=traditional_compatible, as the path_handling feature is stepping into deprecation and path_handling v0 will be the default behaviour when composing upstream_uri.

Discussed with the team and decide to only print deprecation log in the current version.

Full changelog

• Add custom entity check function to deny setting path_handling=v1 when router_flavor is traditional_compatible

[chronolaw]

Good Job.

But I think both traditional_compatible and expression don't support v1, so we should change the condition to kong.configuration.router_flavor ~= "traditional"

[windmgc]

@chronolaw Do you mean router_flavor = atc?

I saw that router_flavor only have three enum results

kong/kong/conf_loader/init.lua

Lines 438 to 440 in 9c990a7

	router_flavor = {
	enum = { "traditional", "traditional_compatible", "atc" },
	},

And when router_flavor = atc the schema will be a different table without the path_handling field in it

kong/kong/db/schema/entities/routes.lua

Lines 6 to 42 in 9c990a7

	if kong and kong.configuration and kong.configuration.router_flavor == "atc" then
	return {
	name = "routes",
	primary_key = { "id" },
	endpoint_key = "name",
	workspaceable = true,
	fields = {
	{ id = typedefs.uuid, },
	{ created_at = typedefs.auto_timestamp_s },
	{ updated_at = typedefs.auto_timestamp_s },
	{ name = typedefs.utf8_name },
	{ protocols = { type = "set",
	len_min = 1,
	required = true,
	elements = typedefs.protocol,
	mutually_exclusive_subsets = {
	{ "http", "https" },
	{ "tcp", "tls", "udp" },
	{ "tls_passthrough" },
	{ "grpc", "grpcs" },
	},
	default = { "http", "https" }, -- TODO: different default depending on service's scheme
	}, },
	{ https_redirect_status_code = { type = "integer",
	one_of = { 426, 301, 302, 307, 308 },
	default = 426, required = true,
	}, },
	{ strip_path = { type = "boolean", required = true, default = true }, },
	{ preserve_host = { type = "boolean", required = true, default = false }, },
	{ request_buffering = { type = "boolean", required = true, default = true }, },
	{ response_buffering = { type = "boolean", required = true, default = true }, },
	{ tags = typedefs.tags },
	{ service = { type = "foreign", reference = "services" }, },
	{ atc = { type = "string", required = true }, },
	{ priority = { type = "integer", required = true, default = 0 }, },
	},

[chronolaw]

Now atc will rename to expression, see #9263 .

[chronolaw]

I think it is not very urgent for 3.0, because the new router only supports v0.

[windmgc]

Yes, agree, not a blocker for 3.0, so no hurry for merging.
And I still need to get the tests fixed :P