feat(configuration): reusable definitions (#8077)

This adds reusable definitions into the mix for the configuration. This replaces the existing networks section for the access_control section and is automatically remapped for users.

Signed-off-by: James Elliott <james-d-elliott@users.noreply.github.com>

1 files changed, 88 insertions, 8 deletions

diff --git a/internal/configuration/provider.go b/internal/configuration/provider.go
index c4f68260d..77c0b3577 100644
--- a/internal/configuration/provider.go
+++ b/internal/configuration/provider.go
@@ -2,6 +2,7 @@ package configuration
 
 import (
 	"fmt"
+	"net"
 
 	"github.com/go-viper/mapstructure/v2"
 	"github.com/knadh/koanf/v2"
@@ -13,21 +14,18 @@ import (
 func Load(val *schema.StructValidator, sources ...Source) (keys []string, configuration *schema.Configuration, err error) {
 	configuration = &schema.Configuration{}
 
-	keys, err = LoadAdvanced(val, "", configuration, sources...)
+	keys, err = LoadAdvanced(val, "", configuration, nil, sources...)
 
 	return keys, configuration, err
 }
 
 // LoadAdvanced is intended to give more flexibility over loading a particular path to a specific interface.
-func LoadAdvanced(val *schema.StructValidator, path string, result any, sources ...Source) (keys []string, err error) {
+func LoadAdvanced(val *schema.StructValidator, path string, result any, definitions *schema.Definitions, sources ...Source) (keys []string, err error) {
 	if val == nil {
 		return keys, errNoValidator
 	}
 
-	ko := koanf.NewWithConf(koanf.Conf{
-		Delim:       constDelimiter,
-		StrictMerge: false,
-	})
+	ko := koanf.NewWithConf(koanf.Conf{Delim: constDelimiter, StrictMerge: false})
 
 	if err = loadSources(ko, val, sources...); err != nil {
 		return ko.Keys(), err
@@ -39,11 +37,88 @@ func LoadAdvanced(val *schema.StructValidator, path string, result any, sources
 		return koanfGetKeys(ko), err
 	}
 
-	unmarshal(final, val, path, result)
+	unmarshal(final, val, path, result, definitions)
+
+	mapDefinitionsResult(val, result)
 
 	return koanfGetKeys(final), nil
 }
 
+func LoadDefinitions(val *schema.StructValidator, sources ...Source) (definitions *schema.Definitions, err error) {
+	ko := koanf.NewWithConf(koanf.Conf{Delim: constDelimiter, StrictMerge: false})
+
+	if err = loadSources(ko, val, sources...); err != nil {
+		return nil, err
+	}
+
+	var final *koanf.Koanf
+
+	if final, err = koanfRemapKeys(val, ko, deprecations, deprecationsMKM); err != nil {
+		return nil, err
+	}
+
+	legacy := &legacyDefinitions{}
+
+	c := koanf.UnmarshalConf{
+		DecoderConfig: &mapstructure.DecoderConfig{
+			DecodeHook: mapstructure.ComposeDecodeHookFunc(
+				mapstructure.StringToSliceHookFunc(","),
+				StringToIPNetworksHookFunc(nil),
+			),
+			Metadata:         nil,
+			Result:           legacy,
+			WeaklyTypedInput: true,
+		},
+	}
+
+	if err = final.UnmarshalWithConf("", legacy, c); err != nil {
+		val.Push(fmt.Errorf("error occurred during unmarshalling definitions configuration: %w", err))
+	}
+
+	d := legacy.Definitions
+
+	mapDefinitions(val, legacy.AccessControl.Networks, &d)
+
+	return &d, nil
+}
+
+func mapDefinitionsResult(val *schema.StructValidator, result any) {
+	if config, ok := result.(*schema.Configuration); ok {
+		mapDefinitions(val, config.AccessControl.Networks, &config.Definitions)
+	}
+}
+
+func mapDefinitions(val *schema.StructValidator, networks []schema.AccessControlNetwork, definitions *schema.Definitions) {
+	if len(networks) == 0 {
+		return
+	}
+
+	var ok bool
+
+	if definitions.Network == nil {
+		definitions.Network = make(map[string][]*net.IPNet, len(networks))
+	}
+
+	for _, network := range networks {
+		if _, ok = definitions.Network[network.Name]; ok {
+			val.Push(fmt.Errorf("error occurred during unmarshalling definitions configuration: the definition for network with name '%s' exists in both the definitions section and access control section which is not permitted", network.Name))
+
+			continue
+		}
+
+		definitions.Network[network.Name] = network.Networks
+	}
+}
+
+type legacyDefinitions struct {
+	Definitions   schema.Definitions  `koanf:"definitions"`
+	AccessControl legacyAccessControl `koanf:"access_control"`
+}
+
+type legacyAccessControl struct {
+	Networks []schema.AccessControlNetwork `koanf:"networks"`
+}
+
 func mapHasKey(k string, m map[string]any) bool {
 	if _, ok := m[k]; ok {
 		return true
@@ -52,7 +127,11 @@ func mapHasKey(k string, m map[string]any) bool {
 	return false
 }
 
-func unmarshal(ko *koanf.Koanf, val *schema.StructValidator, path string, o any) {
+func unmarshal(ko *koanf.Koanf, val *schema.StructValidator, path string, o any, definitions *schema.Definitions) {
+	if definitions == nil {
+		definitions = &schema.Definitions{}
+	}
+
 	c := koanf.UnmarshalConf{
 		DecoderConfig: &mapstructure.DecoderConfig{
 			DecodeHook: mapstructure.ComposeDecodeHookFunc(
@@ -68,6 +147,7 @@ func unmarshal(ko *koanf.Koanf, val *schema.StructValidator, path string, o any)
 				StringToCryptographicKeyHookFunc(),
 				StringToTLSVersionHookFunc(),
 				StringToPasswordDigestHookFunc(),
+				StringToIPNetworksHookFunc(definitions.Network),
 				ToTimeDurationHookFunc(),
 				ToRefreshIntervalDurationHookFunc(),
 			),