opentofu/internal/addrs/module.go
Nathan Baulch ea558d9d4b
Fix typos (#1905)
Signed-off-by: Nathan Baulch <nathan.baulch@gmail.com>
Signed-off-by: Christian Mesh <christianmesh1@gmail.com>
Co-authored-by: Christian Mesh <christianmesh1@gmail.com>
2024-08-29 13:20:33 -04:00

317 lines
9.2 KiB
Go

// Copyright (c) The OpenTofu Authors
// SPDX-License-Identifier: MPL-2.0
// Copyright (c) 2023 HashiCorp, Inc.
// SPDX-License-Identifier: MPL-2.0
package addrs
import (
"strings"
"github.com/hashicorp/hcl/v2"
"github.com/opentofu/opentofu/internal/tfdiags"
)
// Module is an address for a module call within configuration. This is
// the static counterpart of ModuleInstance, representing a traversal through
// the static module call tree in configuration and does not take into account
// the potentially-multiple instances of a module that might be created by
// "count" and "for_each" arguments within those calls.
//
// This type should be used only in very specialized cases when working with
// the static module call tree. Type ModuleInstance is appropriate in more cases.
//
// Although Module is a slice, it should be treated as immutable after creation.
type Module []string
// RootModule is the module address representing the root of the static module
// call tree, which is also the zero value of Module.
//
// Note that this is not the root of the dynamic module tree, which is instead
// represented by RootModuleInstance.
var RootModule Module
// IsRoot returns true if the receiver is the address of the root module,
// or false otherwise.
func (m Module) IsRoot() bool {
return len(m) == 0
}
func (m Module) String() string {
if len(m) == 0 {
return ""
}
// Calculate necessary space.
l := 0
for _, step := range m {
l += len(step)
}
buf := strings.Builder{}
// 8 is len(".module.") which separates entries.
buf.Grow(l + len(m)*8)
sep := ""
for _, step := range m {
buf.WriteString(sep)
buf.WriteString("module.")
buf.WriteString(step)
sep = "."
}
return buf.String()
}
func (m Module) Equal(other Module) bool {
if len(m) != len(other) {
return false
}
for i := range m {
if m[i] != other[i] {
return false
}
}
return true
}
func (m Module) targetableSigil() {
// Module is targetable
}
// TargetContains implements Targetable for Module by returning true if the given other
// address either matches the receiver, is a sub-module-instance of the
// receiver, or is a targetable absolute address within a module that
// is contained within the receiver.
func (m Module) TargetContains(other Targetable) bool {
switch to := other.(type) {
case Module:
if len(to) < len(m) {
// Can't be contained if the path is shorter
return false
}
// Other is contained if its steps match for the length of our own path.
for i, ourStep := range m {
otherStep := to[i]
if ourStep != otherStep {
return false
}
}
// If we fall out here then the prefixed matched, so it's contained.
return true
case ModuleInstance:
return m.TargetContains(to.Module())
case ConfigResource:
return m.TargetContains(to.Module)
case AbsResource:
return m.TargetContains(to.Module)
case AbsResourceInstance:
return m.TargetContains(to.Module)
default:
return false
}
}
func (m Module) AddrType() TargetableAddrType {
return ModuleAddrType
}
// Child returns the address of a child call in the receiver, identified by the
// given name.
func (m Module) Child(name string) Module {
ret := make(Module, 0, len(m)+1)
ret = append(ret, m...)
return append(ret, name)
}
// Parent returns the address of the parent module of the receiver, or the
// receiver itself if there is no parent (if it's the root module address).
func (m Module) Parent() Module {
if len(m) == 0 {
return m
}
return m[:len(m)-1]
}
// Call returns the module call address that corresponds to the given module
// instance, along with the address of the module that contains it.
//
// There is no call for the root module, so this method will panic if called
// on the root module address.
//
// In practice, this just turns the last element of the receiver into a
// ModuleCall and then returns a slice of the receiever that excludes that
// last part. This is just a convenience for situations where a call address
// is required, such as when dealing with *Reference and Referenceable values.
func (m Module) Call() (Module, ModuleCall) {
if len(m) == 0 {
panic("cannot produce ModuleCall for root module")
}
caller, callName := m[:len(m)-1], m[len(m)-1]
return caller, ModuleCall{
Name: callName,
}
}
// Ancestors returns a slice containing the receiver and all of its ancestor
// modules, all the way up to (and including) the root module. The result is
// ordered by depth, with the root module always first.
//
// Since the result always includes the root module, a caller may choose to
// ignore it by slicing the result with [1:].
func (m Module) Ancestors() []Module {
ret := make([]Module, 0, len(m)+1)
for i := 0; i <= len(m); i++ {
ret = append(ret, m[:i])
}
return ret
}
func (m Module) configMoveableSigil() {
// ModuleInstance is moveable
}
func (m Module) configRemovableSigil() {
// Empty function so Module will fulfill the requirements of the removable interface
}
// ParseModule parses a module address from the given traversal,
// which has to contain only the module address with no resource/data/variable/etc.
// This function only supports module addresses without instance keys (as the
// returned Module struct doesn't support instance keys) and will return an
// error if it encounters one.
func ParseModule(traversal hcl.Traversal) (Module, tfdiags.Diagnostics) {
mod, remain, diags := parseModulePrefix(traversal)
if !diags.HasErrors() && len(remain) != 0 {
diags = diags.Append(&hcl.Diagnostic{
Severity: hcl.DiagError,
Summary: "Module address expected",
Detail: "It's not allowed to reference anything other than module here.",
Subject: remain[0].SourceRange().Ptr(),
})
}
return mod, diags
}
// parseModulePrefix parses a module address from the given traversal,
// returning the module address and the remaining traversal.
// For example, if the input traversal is ["module","a","module","b",
// "null_resource", example_resource"], the output module will be ["a", "b"]
// and the output remaining traversal will be ["null_resource",
// "example_resource"].
// This function only supports module addresses without instance keys (as the
// returned Module struct doesn't support instance keys) and will return an
// error if it encounters one.
func parseModulePrefix(traversal hcl.Traversal) (Module, hcl.Traversal, tfdiags.Diagnostics) {
remain := traversal
var module Module
var diags tfdiags.Diagnostics
for len(remain) > 0 {
moduleName, isModule, moduleNameDiags := getModuleName(remain)
diags = diags.Append(moduleNameDiags)
if !isModule || diags.HasErrors() {
break
}
// Because this is a valid module address, we can safely assume that
// the first two elements are "module" and the module name
remain = remain[2:]
if len(remain) > 0 {
// We don't allow module instances as part of the module address
if _, ok := remain[0].(hcl.TraverseIndex); ok {
diags = diags.Append(&hcl.Diagnostic{
Severity: hcl.DiagError,
Summary: "Module instance address with keys is not allowed",
Detail: "Module address cannot be a module instance (e.g. \"module.a[0]\"), it must be a module instead (e.g. \"module.a\").",
Subject: remain[0].SourceRange().Ptr(),
})
return module, remain, diags
}
}
module = append(module, moduleName)
}
var retRemain hcl.Traversal
if len(remain) > 0 {
retRemain = make(hcl.Traversal, len(remain))
copy(retRemain, remain)
// The first element here might be either a TraverseRoot or a
// TraverseAttr, depending on whether we had a module address on the
// front. To make life easier for callers, we'll normalize to always
// start with a TraverseRoot.
if tt, ok := retRemain[0].(hcl.TraverseAttr); ok {
retRemain[0] = hcl.TraverseRoot{
Name: tt.Name,
SrcRange: tt.SrcRange,
}
}
}
return module, retRemain, diags
}
func getModuleName(remain hcl.Traversal) (moduleName string, isModule bool, diags tfdiags.Diagnostics) {
if len(remain) == 0 {
// If the address is empty, then we can't possibly have a module address
return moduleName, false, diags
}
var next string
switch tt := remain[0].(type) {
case hcl.TraverseRoot:
next = tt.Name
case hcl.TraverseAttr:
next = tt.Name
default:
diags = diags.Append(&hcl.Diagnostic{
Severity: hcl.DiagError,
Summary: "Invalid address operator",
Detail: "Module address prefix must be followed by dot and then a name.",
Subject: remain[0].SourceRange().Ptr(),
})
return moduleName, false, diags
}
if next != "module" {
return moduleName, false, diags
}
kwRange := remain[0].SourceRange()
remain = remain[1:]
// If we have the prefix "module" then we should be followed by a
// module call name, as an attribute
if len(remain) == 0 {
diags = diags.Append(&hcl.Diagnostic{
Severity: hcl.DiagError,
Summary: "Invalid address operator",
Detail: "Prefix \"module.\" must be followed by a module name.",
Subject: &kwRange,
})
return moduleName, false, diags
}
switch tt := remain[0].(type) {
case hcl.TraverseAttr:
moduleName = tt.Name
default:
diags = diags.Append(&hcl.Diagnostic{
Severity: hcl.DiagError,
Summary: "Invalid address operator",
Detail: "Prefix \"module.\" must be followed by a module name.",
Subject: remain[0].SourceRange().Ptr(),
})
return moduleName, false, diags
}
return moduleName, true, diags
}