Refactored version directory names

3.0 and 2.0 do not work, there are multiple versions and anything with a period in it sucks from my point of view, v2 and v3 feel much better from a DX perspective.

datamodel/low/v3/header.go

@@ -0,0 +1,88 @@
+// Copyright 2022 Princess B33f Heavy Industries / Dave Shanley
+// SPDX-License-Identifier: MIT
+
+package v3
+
+import (
+	"github.com/pb33f/libopenapi/datamodel/low"
+	"github.com/pb33f/libopenapi/datamodel/low/base"
+	"github.com/pb33f/libopenapi/index"
+	"github.com/pb33f/libopenapi/utils"
+	"gopkg.in/yaml.v3"
+)
+
+const (
+	HeadersLabel = "headers"
+)
+
+type Header struct {
+	Description     low.NodeReference[string]
+	Required        low.NodeReference[bool]
+	Deprecated      low.NodeReference[bool]
+	AllowEmptyValue low.NodeReference[bool]
+	Style           low.NodeReference[string]
+	Explode         low.NodeReference[bool]
+	AllowReserved   low.NodeReference[bool]
+	Schema          low.NodeReference[*base.SchemaProxy]
+	Example         low.NodeReference[any]
+	Examples        low.NodeReference[map[low.KeyReference[string]]low.ValueReference[*base.Example]]
+	Content         low.NodeReference[map[low.KeyReference[string]]low.ValueReference[*MediaType]]
+	Extensions      map[low.KeyReference[string]]low.ValueReference[any]
+}
+
+func (h *Header) FindExtension(ext string) *low.ValueReference[any] {
+	return low.FindItemInMap[any](ext, h.Extensions)
+}
+
+func (h *Header) FindExample(eType string) *low.ValueReference[*base.Example] {
+	return low.FindItemInMap[*base.Example](eType, h.Examples.Value)
+}
+
+func (h *Header) FindContent(ext string) *low.ValueReference[*MediaType] {
+	return low.FindItemInMap[*MediaType](ext, h.Content.Value)
+}
+
+func (h *Header) Build(root *yaml.Node, idx *index.SpecIndex) error {
+	h.Extensions = low.ExtractExtensions(root)
+
+	// handle example if set.
+	_, expLabel, expNode := utils.FindKeyNodeFull(base.ExampleLabel, root.Content)
+	if expNode != nil {
+		h.Example = low.ExtractExample(expNode, expLabel)
+	}
+
+	// handle examples if set.
+	exps, expsL, expsN, eErr := low.ExtractMapFlat[*base.Example](base.ExamplesLabel, root, idx)
+	if eErr != nil {
+		return eErr
+	}
+	if exps != nil {
+		h.Examples = low.NodeReference[map[low.KeyReference[string]]low.ValueReference[*base.Example]]{
+			Value:     exps,
+			KeyNode:   expsL,
+			ValueNode: expsN,
+		}
+	}
+
+	// handle schema
+	sch, sErr := base.ExtractSchema(root, idx)
+	if sErr != nil {
+		return sErr
+	}
+	if sch != nil {
+		h.Schema = *sch
+	}
+
+	// handle content, if set.
+	con, cL, cN, cErr := low.ExtractMapFlat[*MediaType](ContentLabel, root, idx)
+	if cErr != nil {
+		return cErr
+	}
+	h.Content = low.NodeReference[map[low.KeyReference[string]]low.ValueReference[*MediaType]]{
+		Value:     con,
+		KeyNode:   cL,
+		ValueNode: cN,
+	}
+
+	return nil
+}