package configs import ( "fmt" "github.com/hashicorp/hcl/v2" "github.com/hashicorp/hcl/v2/gohcl" "github.com/hashicorp/hcl/v2/hclsyntax" "github.com/hashicorp/terraform/addrs" ) // Resource represents a "resource" or "data" block in a module or file. type Resource struct { Mode addrs.ResourceMode Name string Type string Config hcl.Body Count hcl.Expression ForEach hcl.Expression ProviderConfigRef *ProviderConfigRef Provider addrs.Provider DependsOn []hcl.Traversal // Managed is populated only for Mode = addrs.ManagedResourceMode, // containing the additional fields that apply to managed resources. // For all other resource modes, this field is nil. Managed *ManagedResource DeclRange hcl.Range TypeRange hcl.Range } // ManagedResource represents a "resource" block in a module or file. type ManagedResource struct { Connection *Connection Provisioners []*Provisioner CreateBeforeDestroy bool PreventDestroy bool IgnoreChanges []hcl.Traversal IgnoreAllChanges bool CreateBeforeDestroySet bool PreventDestroySet bool } func (r *Resource) moduleUniqueKey() string { return r.Addr().String() } // Addr returns a resource address for the receiver that is relative to the // resource's containing module. func (r *Resource) Addr() addrs.Resource { return addrs.Resource{ Mode: r.Mode, Type: r.Type, Name: r.Name, } } // ProviderConfigAddr returns the address for the provider configuration that // should be used for this resource. This function returns a default provider // config addr if an explicit "provider" argument was not provided. func (r *Resource) ProviderConfigAddr() addrs.LocalProviderConfig { if r.ProviderConfigRef == nil { // If no specific "provider" argument is given, we want to look up the // provider config where the local name matches the implied provider // from the resource type. This may be different from the resource's // provider type. return addrs.LocalProviderConfig{ LocalName: r.Addr().ImpliedProvider(), } } return addrs.LocalProviderConfig{ LocalName: r.ProviderConfigRef.Name, Alias: r.ProviderConfigRef.Alias, } } func decodeResourceBlock(block *hcl.Block) (*Resource, hcl.Diagnostics) { var diags hcl.Diagnostics r := &Resource{ Mode: addrs.ManagedResourceMode, Type: block.Labels[0], Name: block.Labels[1], DeclRange: block.DefRange, TypeRange: block.LabelRanges[0], Managed: &ManagedResource{}, } content, remain, moreDiags := block.Body.PartialContent(resourceBlockSchema) diags = append(diags, moreDiags...) r.Config = remain if !hclsyntax.ValidIdentifier(r.Type) { diags = append(diags, &hcl.Diagnostic{ Severity: hcl.DiagError, Summary: "Invalid resource type name", Detail: badIdentifierDetail, Subject: &block.LabelRanges[0], }) } if !hclsyntax.ValidIdentifier(r.Name) { diags = append(diags, &hcl.Diagnostic{ Severity: hcl.DiagError, Summary: "Invalid resource name", Detail: badIdentifierDetail, Subject: &block.LabelRanges[1], }) } if attr, exists := content.Attributes["count"]; exists { r.Count = attr.Expr } if attr, exists := content.Attributes["for_each"]; exists { r.ForEach = attr.Expr // Cannot have count and for_each on the same resource block if r.Count != nil { diags = append(diags, &hcl.Diagnostic{ Severity: hcl.DiagError, Summary: `Invalid combination of "count" and "for_each"`, Detail: `The "count" and "for_each" meta-arguments are mutually-exclusive, only one should be used to be explicit about the number of resources to be created.`, Subject: &attr.NameRange, }) } } if attr, exists := content.Attributes["provider"]; exists { var providerDiags hcl.Diagnostics r.ProviderConfigRef, providerDiags = decodeProviderConfigRef(attr.Expr, "provider") diags = append(diags, providerDiags...) } if attr, exists := content.Attributes["depends_on"]; exists { deps, depsDiags := decodeDependsOn(attr) diags = append(diags, depsDiags...) r.DependsOn = append(r.DependsOn, deps...) } var seenLifecycle *hcl.Block var seenConnection *hcl.Block var seenEscapeBlock *hcl.Block for _, block := range content.Blocks { switch block.Type { case "lifecycle": if seenLifecycle != nil { diags = append(diags, &hcl.Diagnostic{ Severity: hcl.DiagError, Summary: "Duplicate lifecycle block", Detail: fmt.Sprintf("This resource already has a lifecycle block at %s.", seenLifecycle.DefRange), Subject: &block.DefRange, }) continue } seenLifecycle = block lcContent, lcDiags := block.Body.Content(resourceLifecycleBlockSchema) diags = append(diags, lcDiags...) if attr, exists := lcContent.Attributes["create_before_destroy"]; exists { valDiags := gohcl.DecodeExpression(attr.Expr, nil, &r.Managed.CreateBeforeDestroy) diags = append(diags, valDiags...) r.Managed.CreateBeforeDestroySet = true } if attr, exists := lcContent.Attributes["prevent_destroy"]; exists { valDiags := gohcl.DecodeExpression(attr.Expr, nil, &r.Managed.PreventDestroy) diags = append(diags, valDiags...) r.Managed.PreventDestroySet = true } if attr, exists := lcContent.Attributes["ignore_changes"]; exists { // ignore_changes can either be a list of relative traversals // or it can be just the keyword "all" to ignore changes to this // resource entirely. // ignore_changes = [ami, instance_type] // ignore_changes = all // We also allow two legacy forms for compatibility with earlier // versions: // ignore_changes = ["ami", "instance_type"] // ignore_changes = ["*"] kw := hcl.ExprAsKeyword(attr.Expr) switch { case kw == "all": r.Managed.IgnoreAllChanges = true default: exprs, listDiags := hcl.ExprList(attr.Expr) diags = append(diags, listDiags...) var ignoreAllRange hcl.Range for _, expr := range exprs { // our expr might be the literal string "*", which // we accept as a deprecated way of saying "all". if shimIsIgnoreChangesStar(expr) { r.Managed.IgnoreAllChanges = true ignoreAllRange = expr.Range() diags = append(diags, &hcl.Diagnostic{ Severity: hcl.DiagError, Summary: "Invalid ignore_changes wildcard", Detail: "The [\"*\"] form of ignore_changes wildcard is was deprecated and is now invalid. Use \"ignore_changes = all\" to ignore changes to all attributes.", Subject: attr.Expr.Range().Ptr(), }) continue } expr, shimDiags := shimTraversalInString(expr, false) diags = append(diags, shimDiags...) traversal, travDiags := hcl.RelTraversalForExpr(expr) diags = append(diags, travDiags...) if len(traversal) != 0 { r.Managed.IgnoreChanges = append(r.Managed.IgnoreChanges, traversal) } } if r.Managed.IgnoreAllChanges && len(r.Managed.IgnoreChanges) != 0 { diags = append(diags, &hcl.Diagnostic{ Severity: hcl.DiagError, Summary: "Invalid ignore_changes ruleset", Detail: "Cannot mix wildcard string \"*\" with non-wildcard references.", Subject: &ignoreAllRange, Context: attr.Expr.Range().Ptr(), }) } } } case "connection": if seenConnection != nil { diags = append(diags, &hcl.Diagnostic{ Severity: hcl.DiagError, Summary: "Duplicate connection block", Detail: fmt.Sprintf("This resource already has a connection block at %s.", seenConnection.DefRange), Subject: &block.DefRange, }) continue } seenConnection = block r.Managed.Connection = &Connection{ Config: block.Body, DeclRange: block.DefRange, } case "provisioner": pv, pvDiags := decodeProvisionerBlock(block) diags = append(diags, pvDiags...) if pv != nil { r.Managed.Provisioners = append(r.Managed.Provisioners, pv) } case "_": if seenEscapeBlock != nil { diags = append(diags, &hcl.Diagnostic{ Severity: hcl.DiagError, Summary: "Duplicate escaping block", Detail: fmt.Sprintf( "The special block type \"_\" can be used to force particular arguments to be interpreted as resource-type-specific rather than as meta-arguments, but each resource block can have only one such block. The first escaping block was at %s.", seenEscapeBlock.DefRange, ), Subject: &block.DefRange, }) continue } seenEscapeBlock = block // When there's an escaping block its content merges with the // existing config we extracted earlier, so later decoding // will see a blend of both. r.Config = hcl.MergeBodies([]hcl.Body{r.Config, block.Body}) default: // Any other block types are ones we've reserved for future use, // so they get a generic message. diags = append(diags, &hcl.Diagnostic{ Severity: hcl.DiagError, Summary: "Reserved block type name in resource block", Detail: fmt.Sprintf("The block type name %q is reserved for use by Terraform in a future version.", block.Type), Subject: &block.TypeRange, }) } } // Now we can validate the connection block references if there are any destroy provisioners. // TODO: should we eliminate standalone connection blocks? if r.Managed.Connection != nil { for _, p := range r.Managed.Provisioners { if p.When == ProvisionerWhenDestroy { diags = append(diags, onlySelfRefs(r.Managed.Connection.Config)...) break } } } return r, diags } func decodeDataBlock(block *hcl.Block) (*Resource, hcl.Diagnostics) { var diags hcl.Diagnostics r := &Resource{ Mode: addrs.DataResourceMode, Type: block.Labels[0], Name: block.Labels[1], DeclRange: block.DefRange, TypeRange: block.LabelRanges[0], } content, remain, moreDiags := block.Body.PartialContent(dataBlockSchema) diags = append(diags, moreDiags...) r.Config = remain if !hclsyntax.ValidIdentifier(r.Type) { diags = append(diags, &hcl.Diagnostic{ Severity: hcl.DiagError, Summary: "Invalid data source name", Detail: badIdentifierDetail, Subject: &block.LabelRanges[0], }) } if !hclsyntax.ValidIdentifier(r.Name) { diags = append(diags, &hcl.Diagnostic{ Severity: hcl.DiagError, Summary: "Invalid data resource name", Detail: badIdentifierDetail, Subject: &block.LabelRanges[1], }) } if attr, exists := content.Attributes["count"]; exists { r.Count = attr.Expr } if attr, exists := content.Attributes["for_each"]; exists { r.ForEach = attr.Expr // Cannot have count and for_each on the same data block if r.Count != nil { diags = append(diags, &hcl.Diagnostic{ Severity: hcl.DiagError, Summary: `Invalid combination of "count" and "for_each"`, Detail: `The "count" and "for_each" meta-arguments are mutually-exclusive, only one should be used to be explicit about the number of resources to be created.`, Subject: &attr.NameRange, }) } } if attr, exists := content.Attributes["provider"]; exists { var providerDiags hcl.Diagnostics r.ProviderConfigRef, providerDiags = decodeProviderConfigRef(attr.Expr, "provider") diags = append(diags, providerDiags...) } if attr, exists := content.Attributes["depends_on"]; exists { deps, depsDiags := decodeDependsOn(attr) diags = append(diags, depsDiags...) r.DependsOn = append(r.DependsOn, deps...) } var seenEscapeBlock *hcl.Block for _, block := range content.Blocks { switch block.Type { case "_": if seenEscapeBlock != nil { diags = append(diags, &hcl.Diagnostic{ Severity: hcl.DiagError, Summary: "Duplicate escaping block", Detail: fmt.Sprintf( "The special block type \"_\" can be used to force particular arguments to be interpreted as resource-type-specific rather than as meta-arguments, but each data block can have only one such block. The first escaping block was at %s.", seenEscapeBlock.DefRange, ), Subject: &block.DefRange, }) continue } seenEscapeBlock = block // When there's an escaping block its content merges with the // existing config we extracted earlier, so later decoding // will see a blend of both. r.Config = hcl.MergeBodies([]hcl.Body{r.Config, block.Body}) // The rest of these are just here to reserve block type names for future use. case "lifecycle": diags = append(diags, &hcl.Diagnostic{ Severity: hcl.DiagError, Summary: "Unsupported lifecycle block", Detail: "Data resources do not have lifecycle settings, so a lifecycle block is not allowed.", Subject: &block.DefRange, }) default: diags = append(diags, &hcl.Diagnostic{ Severity: hcl.DiagError, Summary: "Reserved block type name in data block", Detail: fmt.Sprintf("The block type name %q is reserved for use by Terraform in a future version.", block.Type), Subject: &block.TypeRange, }) } } return r, diags } type ProviderConfigRef struct { Name string NameRange hcl.Range Alias string AliasRange *hcl.Range // nil if alias not set // TODO: this may not be set in some cases, so it is not yet suitable for // use outside of this package. We currently only use it for internal // validation, but once we verify that this can be set in all cases, we can // export this so providers don't need to be re-resolved. // This same field is also added to the Provider struct. providerType addrs.Provider } func decodeProviderConfigRef(expr hcl.Expression, argName string) (*ProviderConfigRef, hcl.Diagnostics) { var diags hcl.Diagnostics var shimDiags hcl.Diagnostics expr, shimDiags = shimTraversalInString(expr, false) diags = append(diags, shimDiags...) traversal, travDiags := hcl.AbsTraversalForExpr(expr) // AbsTraversalForExpr produces only generic errors, so we'll discard // the errors given and produce our own with extra context. If we didn't // get any errors then we might still have warnings, though. if !travDiags.HasErrors() { diags = append(diags, travDiags...) } if len(traversal) < 1 || len(traversal) > 2 { // A provider reference was given as a string literal in the legacy // configuration language and there are lots of examples out there // showing that usage, so we'll sniff for that situation here and // produce a specialized error message for it to help users find // the new correct form. if exprIsNativeQuotedString(expr) { diags = append(diags, &hcl.Diagnostic{ Severity: hcl.DiagError, Summary: "Invalid provider configuration reference", Detail: "A provider configuration reference must not be given in quotes.", Subject: expr.Range().Ptr(), }) return nil, diags } diags = append(diags, &hcl.Diagnostic{ Severity: hcl.DiagError, Summary: "Invalid provider configuration reference", Detail: fmt.Sprintf("The %s argument requires a provider type name, optionally followed by a period and then a configuration alias.", argName), Subject: expr.Range().Ptr(), }) return nil, diags } // verify that the provider local name is normalized name := traversal.RootName() nameDiags := checkProviderNameNormalized(name, traversal[0].SourceRange()) diags = append(diags, nameDiags...) if diags.HasErrors() { return nil, diags } ret := &ProviderConfigRef{ Name: name, NameRange: traversal[0].SourceRange(), } if len(traversal) > 1 { aliasStep, ok := traversal[1].(hcl.TraverseAttr) if !ok { diags = append(diags, &hcl.Diagnostic{ Severity: hcl.DiagError, Summary: "Invalid provider configuration reference", Detail: "Provider name must either stand alone or be followed by a period and then a configuration alias.", Subject: traversal[1].SourceRange().Ptr(), }) return ret, diags } ret.Alias = aliasStep.Name ret.AliasRange = aliasStep.SourceRange().Ptr() } return ret, diags } // Addr returns the provider config address corresponding to the receiving // config reference. // // This is a trivial conversion, essentially just discarding the source // location information and keeping just the addressing information. func (r *ProviderConfigRef) Addr() addrs.LocalProviderConfig { return addrs.LocalProviderConfig{ LocalName: r.Name, Alias: r.Alias, } } func (r *ProviderConfigRef) String() string { if r == nil { return "" } if r.Alias != "" { return fmt.Sprintf("%s.%s", r.Name, r.Alias) } return r.Name } var commonResourceAttributes = []hcl.AttributeSchema{ { Name: "count", }, { Name: "for_each", }, { Name: "provider", }, { Name: "depends_on", }, } var resourceBlockSchema = &hcl.BodySchema{ Attributes: commonResourceAttributes, Blocks: []hcl.BlockHeaderSchema{ {Type: "locals"}, // reserved for future use {Type: "lifecycle"}, {Type: "connection"}, {Type: "provisioner", LabelNames: []string{"type"}}, {Type: "_"}, // meta-argument escaping block }, } var dataBlockSchema = &hcl.BodySchema{ Attributes: commonResourceAttributes, Blocks: []hcl.BlockHeaderSchema{ {Type: "lifecycle"}, // reserved for future use {Type: "locals"}, // reserved for future use {Type: "_"}, // meta-argument escaping block }, } var resourceLifecycleBlockSchema = &hcl.BodySchema{ Attributes: []hcl.AttributeSchema{ { Name: "create_before_destroy", }, { Name: "prevent_destroy", }, { Name: "ignore_changes", }, }, }