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[github/fretlink/terraform-provider-statuscake.git] / vendor / github.com / hashicorp / terraform / addrs / module_instance.go

package addrs

import (
        "bytes"
        "fmt"

        "github.com/hashicorp/hcl2/hcl"
        "github.com/hashicorp/hcl2/hcl/hclsyntax"
        "github.com/zclconf/go-cty/cty"
        "github.com/zclconf/go-cty/cty/gocty"

        "github.com/hashicorp/terraform/tfdiags"
)

// ModuleInstance is an address for a particular module instance within the
// dynamic module tree. This is an extension of the static traversals
// represented by type Module that deals with the possibility of a single
// module call producing multiple instances via the "count" and "for_each"
// arguments.
//
// Although ModuleInstance is a slice, it should be treated as immutable after
// creation.
type ModuleInstance []ModuleInstanceStep

var (
        _ Targetable = ModuleInstance(nil)
)

func ParseModuleInstance(traversal hcl.Traversal) (ModuleInstance, tfdiags.Diagnostics) {
        mi, remain, diags := parseModuleInstancePrefix(traversal)
        if len(remain) != 0 {
                if len(remain) == len(traversal) {
                        diags = diags.Append(&hcl.Diagnostic{
                                Severity: hcl.DiagError,
                                Summary:  "Invalid module instance address",
                                Detail:   "A module instance address must begin with \"module.\".",
                                Subject:  remain.SourceRange().Ptr(),
                        })
                } else {
                        diags = diags.Append(&hcl.Diagnostic{
                                Severity: hcl.DiagError,
                                Summary:  "Invalid module instance address",
                                Detail:   "The module instance address is followed by additional invalid content.",
                                Subject:  remain.SourceRange().Ptr(),
                        })
                }
        }
        return mi, diags
}

// ParseModuleInstanceStr is a helper wrapper around ParseModuleInstance
// that takes a string and parses it with the HCL native syntax traversal parser
// before interpreting it.
//
// This should be used only in specialized situations since it will cause the
// created references to not have any meaningful source location information.
// If a reference string is coming from a source that should be identified in
// error messages then the caller should instead parse it directly using a
// suitable function from the HCL API and pass the traversal itself to
// ParseProviderConfigCompact.
//
// Error diagnostics are returned if either the parsing fails or the analysis
// of the traversal fails. There is no way for the caller to distinguish the
// two kinds of diagnostics programmatically. If error diagnostics are returned
// then the returned address is invalid.
func ParseModuleInstanceStr(str string) (ModuleInstance, tfdiags.Diagnostics) {
        var diags tfdiags.Diagnostics

        traversal, parseDiags := hclsyntax.ParseTraversalAbs([]byte(str), "", hcl.Pos{Line: 1, Column: 1})
        diags = diags.Append(parseDiags)
        if parseDiags.HasErrors() {
                return nil, diags
        }

        addr, addrDiags := ParseModuleInstance(traversal)
        diags = diags.Append(addrDiags)
        return addr, diags
}

func parseModuleInstancePrefix(traversal hcl.Traversal) (ModuleInstance, hcl.Traversal, tfdiags.Diagnostics) {
        remain := traversal
        var mi ModuleInstance
        var diags tfdiags.Diagnostics

        for len(remain) > 0 {
                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(),
                        })
                        break
                }

                if next != "module" {
                        break
                }

                kwRange := remain[0].SourceRange()
                remain = remain[1:]
                // If we have the prefix "module" then we should be followed by an
                // module call name, as an attribute, and then optionally an index step
                // giving the instance key.
                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,
                        })
                        break
                }

                var moduleName string
                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(),
                        })
                        break
                }
                remain = remain[1:]
                step := ModuleInstanceStep{
                        Name: moduleName,
                }

                if len(remain) > 0 {
                        if idx, ok := remain[0].(hcl.TraverseIndex); ok {
                                remain = remain[1:]

                                switch idx.Key.Type() {
                                case cty.String:
                                        step.InstanceKey = StringKey(idx.Key.AsString())
                                case cty.Number:
                                        var idxInt int
                                        err := gocty.FromCtyValue(idx.Key, &idxInt)
                                        if err == nil {
                                                step.InstanceKey = IntKey(idxInt)
                                        } else {
                                                diags = diags.Append(&hcl.Diagnostic{
                                                        Severity: hcl.DiagError,
                                                        Summary:  "Invalid address operator",
                                                        Detail:   fmt.Sprintf("Invalid module index: %s.", err),
                                                        Subject:  idx.SourceRange().Ptr(),
                                                })
                                        }
                                default:
                                        // Should never happen, because no other types are allowed in traversal indices.
                                        diags = diags.Append(&hcl.Diagnostic{
                                                Severity: hcl.DiagError,
                                                Summary:  "Invalid address operator",
                                                Detail:   "Invalid module key: must be either a string or an integer.",
                                                Subject:  idx.SourceRange().Ptr(),
                                        })
                                }
                        }
                }

                mi = append(mi, step)
        }

        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 mi, retRemain, diags
}

// UnkeyedInstanceShim is a shim method for converting a Module address to the
// equivalent ModuleInstance address that assumes that no modules have
// keyed instances.
//
// This is a temporary allowance for the fact that Terraform does not presently
// support "count" and "for_each" on modules, and thus graph building code that
// derives graph nodes from configuration must just assume unkeyed modules
// in order to construct the graph. At a later time when "count" and "for_each"
// support is added for modules, all callers of this method will need to be
// reworked to allow for keyed module instances.
func (m Module) UnkeyedInstanceShim() ModuleInstance {
        path := make(ModuleInstance, len(m))
        for i, name := range m {
                path[i] = ModuleInstanceStep{Name: name}
        }
        return path
}

// ModuleInstanceStep is a single traversal step through the dynamic module
// tree. It is used only as part of ModuleInstance.
type ModuleInstanceStep struct {
        Name        string
        InstanceKey InstanceKey
}

// RootModuleInstance is the module instance address representing the root
// module, which is also the zero value of ModuleInstance.
var RootModuleInstance ModuleInstance

// IsRoot returns true if the receiver is the address of the root module instance,
// or false otherwise.
func (m ModuleInstance) IsRoot() bool {
        return len(m) == 0
}

// Child returns the address of a child module instance of the receiver,
// identified by the given name and key.
func (m ModuleInstance) Child(name string, key InstanceKey) ModuleInstance {
        ret := make(ModuleInstance, 0, len(m)+1)
        ret = append(ret, m...)
        return append(ret, ModuleInstanceStep{
                Name:        name,
                InstanceKey: key,
        })
}

// Parent returns the address of the parent module instance of the receiver, or
// the receiver itself if there is no parent (if it's the root module address).
func (m ModuleInstance) Parent() ModuleInstance {
        if len(m) == 0 {
                return m
        }
        return m[:len(m)-1]
}

// String returns a string representation of the receiver, in the format used
// within e.g. user-provided resource addresses.
//
// The address of the root module has the empty string as its representation.
func (m ModuleInstance) String() string {
        var buf bytes.Buffer
        sep := ""
        for _, step := range m {
                buf.WriteString(sep)
                buf.WriteString("module.")
                buf.WriteString(step.Name)
                if step.InstanceKey != NoKey {
                        buf.WriteString(step.InstanceKey.String())
                }
                sep = "."
        }
        return buf.String()
}

// Equal returns true if the receiver and the given other value
// contains the exact same parts.
func (m ModuleInstance) Equal(o ModuleInstance) bool {
        return m.String() == o.String()
}

// Less returns true if the receiver should sort before the given other value
// in a sorted list of addresses.
func (m ModuleInstance) Less(o ModuleInstance) bool {
        if len(m) != len(o) {
                // Shorter path sorts first.
                return len(m) < len(o)
        }

        for i := range m {
                mS, oS := m[i], o[i]
                switch {
                case mS.Name != oS.Name:
                        return mS.Name < oS.Name
                case mS.InstanceKey != oS.InstanceKey:
                        return InstanceKeyLess(mS.InstanceKey, oS.InstanceKey)
                }
        }

        return false
}

// Ancestors returns a slice containing the receiver and all of its ancestor
// module instances, 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 ModuleInstance) Ancestors() []ModuleInstance {
        ret := make([]ModuleInstance, 0, len(m)+1)
        for i := 0; i <= len(m); i++ {
                ret = append(ret, m[:i])
        }
        return ret
}

// IsAncestor returns true if the receiver is an ancestor of the given
// other value.
func (m ModuleInstance) IsAncestor(o ModuleInstance) bool {
        // Longer or equal sized paths means the receiver cannot
        // be an ancestor of the given module insatnce.
        if len(m) >= len(o) {
                return false
        }

        for i, ms := range m {
                if ms.Name != o[i].Name {
                        return false
                }
                if ms.InstanceKey != NoKey && ms.InstanceKey != o[i].InstanceKey {
                        return false
                }
        }

        return true
}

// Call returns the module call address that corresponds to the given module
// instance, along with the address of the module instance that contains it.
//
// There is no call for the root module, so this method will panic if called
// on the root module address.
//
// A single module call can produce potentially many module instances, so the
// result discards any instance key that might be present on the last step
// of the instance. To retain this, use CallInstance instead.
//
// 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 Referencable values.
func (m ModuleInstance) Call() (ModuleInstance, ModuleCall) {
        if len(m) == 0 {
                panic("cannot produce ModuleCall for root module")
        }

        inst, lastStep := m[:len(m)-1], m[len(m)-1]
        return inst, ModuleCall{
                Name: lastStep.Name,
        }
}

// CallInstance returns the module call instance address that corresponds to
// the given module instance, along with the address of the module instance
// 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
// ModuleCallInstance 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 Referencable
// values.
func (m ModuleInstance) CallInstance() (ModuleInstance, ModuleCallInstance) {
        if len(m) == 0 {
                panic("cannot produce ModuleCallInstance for root module")
        }

        inst, lastStep := m[:len(m)-1], m[len(m)-1]
        return inst, ModuleCallInstance{
                Call: ModuleCall{
                        Name: lastStep.Name,
                },
                Key: lastStep.InstanceKey,
        }
}

// TargetContains implements Targetable 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 reciever.
func (m ModuleInstance) TargetContains(other Targetable) bool {
        switch to := other.(type) {

        case ModuleInstance:
                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 AbsResource:
                return m.TargetContains(to.Module)

        case AbsResourceInstance:
                return m.TargetContains(to.Module)

        default:
                return false
        }
}

func (m ModuleInstance) targetableSigil() {
        // ModuleInstance is targetable
}