luci-compat: CBI skip fields that do not satisfy depends

[jjm2473]

If depends is not satisfied, the fvalue will be nil.

@jow-

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A simple test code (model/cbi/abc.lua):

local m, s, o

m = Map("floatip", translate("FloatingGateway"))

s=m:section(NamedSection, "main", translate("Global settings"))
s.anonymous=true

o = s:option(Flag, "enabled", translate("Enable"))
o.rmempty = false

o = s:option(ListValue, "role", translate("Node Role"))
o.rmempty = false
o.widget = "select"
o:value("main", translate("Preempt Node"))
o:value("fallback", translate("Fallback Node"))

o = s:option(Value, "set_ip", translate("Floating Gateway IP"))
o.rmempty = false
o.datatype = "or(ip4addr,cidr4)"

o = s:option(Value, "check_ip", translate("Preempt Node IP"))
o.rmempty = false
o.datatype = "ip4addr"
o:depends("role", "fallback")

return m

Without this patch, when "role" changes from "fallback" to "main", save will failed with 'missing' error (One or more required fields have no value!).

[jow-]

Please do not introduce new options into the legacy Lua cbi library.

[jjm2473]

Please do not introduce new options into the legacy Lua cbi library.

It's not an option, 'nilasempty' just a flag for internal usage, frontend pass nil when list empty.

If we don't do this, how can we fix the luci bug?

luci-app-dockerman is also affected by this bug. First switch "Remote Endpoint" to true, set "Remote Host" to "10.1.1.2", set "Remote Port" to "2375", save and apply; then switch "Remote Endpoint" to false. At this time, no matter how you set parameters, it will not be saved.

[jjm2473]

The key point is that we should not check 'rmempty = false' when depends is not satisfied.

[jjm2473]

Dockerman issue: #7508

[systemcrash]

In this case, I think docker's o.rmempty = true for those two options could be the correct way forward. Have you tried that?

[jjm2473]

@systemcrash

In this case, I think docker's o.rmempty = true for those two options could be the correct way forward. Have you tried that?

Maybe that can save. But when "Remote Endpoint" enabled, user must set "Remote Host" and "Remote Port", so o.rmempty must be false.

[systemcrash]

so o.rmempty must be false.

why?

[jjm2473]

why?

When "Remote Endpoint" mode, "Remote Host" and "Remote Port" are all required.