opentofu/internal/addrs/module_call.go
Martin Atkins f3a57db293 addrs: UniqueKey and UniqueKeyer
Many times now we've seen situations where we need to use addresses
as map keys, but not all of our address types are comparable and thus
we tend to end up using string representations as keys instead.

That's problematic because conversion to string uses type information
and some of the address types have string representations that are
ambiguous with one another.

UniqueKey therefore represents an opaque key that is unique for each
functionally-distinct address across all types that implement
UniqueKeyer.

For this initial commit I've implemented UniqueKeyer only for the
Referenceable family of types. These are an easy case because they
were all already comparable (intentionally) anyway. Later commits
can implement UniqueKeyer for other types that are not naturally
comparable, such as any which include a ModuleInstance.

This also includes a new type addrs.Set which wraps a map as a set
of addresses, using the unique keys to ensure that there can be only
one element for each distinct address.
2021-07-14 17:37:48 -07:00

173 lines
4.5 KiB
Go

package addrs
import (
"fmt"
)
// ModuleCall is the address of a call from the current module to a child
// module.
type ModuleCall struct {
referenceable
Name string
}
func (c ModuleCall) String() string {
return "module." + c.Name
}
func (c ModuleCall) UniqueKey() UniqueKey {
return c // A ModuleCall is its own UniqueKey
}
func (c ModuleCall) uniqueKeySigil() {}
// Instance returns the address of an instance of the receiver identified by
// the given key.
func (c ModuleCall) Instance(key InstanceKey) ModuleCallInstance {
return ModuleCallInstance{
Call: c,
Key: key,
}
}
func (c ModuleCall) Absolute(moduleAddr ModuleInstance) AbsModuleCall {
return AbsModuleCall{
Module: moduleAddr,
Call: c,
}
}
// AbsModuleCall is the address of a "module" block relative to the root
// of the configuration.
//
// This is similar to ModuleInstance alone, but specifically represents
// the module block itself rather than any one of the instances that
// module block declares.
type AbsModuleCall struct {
Module ModuleInstance
Call ModuleCall
}
func (c AbsModuleCall) absMoveableSigil() {
// AbsModuleCall is "moveable".
}
func (c AbsModuleCall) String() string {
return fmt.Sprintf("%s.%s", c.Module, c.Call.Name)
}
func (c AbsModuleCall) Instance(key InstanceKey) ModuleInstance {
ret := make(ModuleInstance, len(c.Module), len(c.Module)+1)
copy(ret, c.Module)
ret = append(ret, ModuleInstanceStep{
Name: c.Call.Name,
InstanceKey: key,
})
return ret
}
// ModuleCallInstance is the address of one instance of a module created from
// a module call, which might create multiple instances using "count" or
// "for_each" arguments.
//
// There is no "Abs" version of ModuleCallInstance because an absolute module
// path is represented by ModuleInstance.
type ModuleCallInstance struct {
referenceable
Call ModuleCall
Key InstanceKey
}
func (c ModuleCallInstance) String() string {
if c.Key == NoKey {
return c.Call.String()
}
return fmt.Sprintf("module.%s%s", c.Call.Name, c.Key)
}
func (c ModuleCallInstance) UniqueKey() UniqueKey {
return c // A ModuleCallInstance is its own UniqueKey
}
func (c ModuleCallInstance) uniqueKeySigil() {}
func (c ModuleCallInstance) Absolute(moduleAddr ModuleInstance) ModuleInstance {
ret := make(ModuleInstance, len(moduleAddr), len(moduleAddr)+1)
copy(ret, moduleAddr)
ret = append(ret, ModuleInstanceStep{
Name: c.Call.Name,
InstanceKey: c.Key,
})
return ret
}
// ModuleInstance returns the address of the module instance that corresponds
// to the receiving call instance when resolved in the given calling module.
// In other words, it returns the child module instance that the receving
// call instance creates.
func (c ModuleCallInstance) ModuleInstance(caller ModuleInstance) ModuleInstance {
return caller.Child(c.Call.Name, c.Key)
}
// Output returns the absolute address of an output of the receiver identified by its
// name.
func (c ModuleCallInstance) Output(name string) ModuleCallInstanceOutput {
return ModuleCallInstanceOutput{
Call: c,
Name: name,
}
}
// ModuleCallOutput is the address of a named output and its associated
// ModuleCall, which may expand into multiple module instances
type ModuleCallOutput struct {
referenceable
Call ModuleCall
Name string
}
func (m ModuleCallOutput) String() string {
return fmt.Sprintf("%s.%s", m.Call.String(), m.Name)
}
func (m ModuleCallOutput) UniqueKey() UniqueKey {
return m // A ModuleCallOutput is its own UniqueKey
}
func (m ModuleCallOutput) uniqueKeySigil() {}
// ModuleCallInstanceOutput is the address of a particular named output produced by
// an instance of a module call.
type ModuleCallInstanceOutput struct {
referenceable
Call ModuleCallInstance
Name string
}
// ModuleCallOutput returns the referenceable ModuleCallOutput for this
// particular instance.
func (co ModuleCallInstanceOutput) ModuleCallOutput() ModuleCallOutput {
return ModuleCallOutput{
Call: co.Call.Call,
Name: co.Name,
}
}
func (co ModuleCallInstanceOutput) String() string {
return fmt.Sprintf("%s.%s", co.Call.String(), co.Name)
}
func (co ModuleCallInstanceOutput) UniqueKey() UniqueKey {
return co // A ModuleCallInstanceOutput is its own UniqueKey
}
func (co ModuleCallInstanceOutput) uniqueKeySigil() {}
// AbsOutputValue returns the absolute output value address that corresponds
// to the receving module call output address, once resolved in the given
// calling module.
func (co ModuleCallInstanceOutput) AbsOutputValue(caller ModuleInstance) AbsOutputValue {
moduleAddr := co.Call.ModuleInstance(caller)
return moduleAddr.OutputValue(co.Name)
}