dns: better config (#1273)

* change config struct

* make use of new config

* add registry for reflection

* update docs

* simplify hooks docs

docs/content/docs/_gravity-hook-env.md

@@ -0,0 +1,23 @@
+### `gravity` Object
+
+#### `log(msg: any)`
+
+Logs a message to the stdout of the Gravity node this hook is run on.
+
+#### `node: string`
+
+The identifier of the node this hook is run on.
+
+#### `version: string`
+
+The version of Gravity on the node this hook is run on.
+
+#### `role`
+
+A reference to the [Role instance](https://pkg.go.dev/beryju.io/gravity/pkg/instance#RoleInstance) this hook was triggered by.
+
+### `net` Object
+
+#### `parseIP(ip: string, family: string)`
+
+Parse an IP address from the string `ip` and return it as an array of bytes. `family` determines if the IP should be parsed as IPv4 or IPv6.</p>

docs/content/docs/dhcp/hooks.md

@@ -19,7 +19,7 @@ Called after the DHCP response is generated.
 
 ## Environment
 
-{{< gravity-hook-env >}}
+{{< readfile "/docs/_gravity-hook-env.md" >}}
 
 ### `dhcp` Object
 

docs/content/docs/dns/hooks.md

@@ -19,4 +19,4 @@ Called after the DNS response is generated.
 
 ## Environment
 
-{{< gravity-hook-env >}}
+{{< readfile "/docs/_gravity-hook-env.md" >}}

docs/content/docs/dns/zones.md

@@ -10,7 +10,7 @@ The order of handler matters; Gravity will send a query to each handler in the o
 The handler configuration consists of a list of individual handler configurations. All list entries require a `type` attribute which must match one of the headers listed below. For example:
 
 ```yaml
-- cache_ttl: "3600"
+- cache_ttl: 3600
   to: 8.8.8.8:53
   type: forward_blocky
 - to: 8.8.8.8:53
@@ -50,6 +50,8 @@ Forward queries to another DNS server.
 
   Multiple servers should be separated by `;`. For example `8.8.8.8:53;1.1.1.1`.
 
+  Starting with Gravity 0.14, this can also be set as a JSON/YAML array using `[8.8.8.8:53, 1.1.1.1:53]` instead of a semicolon-separated string.
+
 - `cache_ttl`: Optional TTL to cache responses in etcd.
 
   Defaults to 0. Attempts to cache for the TTL of the response.
@@ -72,6 +74,8 @@ Forward queries to another DNS server via Blocky for advert/privacy blocking.
 
   Multiple servers should be separated by `;`. For example `8.8.8.8:53;1.1.1.1`.
 
+  Starting with Gravity 0.14, this can also be set as a JSON/YAML array using `[8.8.8.8:53, 1.1.1.1:53]` instead of a semicolon-separated string.
+
 - `cache_ttl`: Optional TTL to cache responses in etcd
 
   Defaults to 0. Attempts to cache for the TTL of the response.
@@ -82,6 +86,8 @@ Forward queries to another DNS server via Blocky for advert/privacy blocking.
 
   Entries beginning with http:// or https:// are downloaded when the DNS Role is started. Can also be set to an inline list of domains to block/allow. Multiple entries should be separated by a `;`.
 
+  Starting with Gravity 0.14, this can also be set as a JSON/YAML array using `[https://foo, https://bar]` instead of a semicolon-separated string.
+
   By default, these blocklists are loaded:
 
   - https://adaway.org/hosts.txt
@@ -98,7 +104,10 @@ Forward queries to another DNS server via Blocky for advert/privacy blocking.
 ```yaml
 - type: forward_blocky
   to: 8.8.8.8
-  blocklists: https://adaway.org/hosts.txt
+  blocklists:
+    - https://adaway.org/hosts.txt
+  allowlists:
+    - exception.com
 ```
 
 ### `coredns`
@@ -131,4 +140,4 @@ Resolve queries by using a variety of CoreDNS Plugins. See [here](https://coredn
 
 ## Hooks
 
-Optional hooks to dynamically modify requests and responses. See [Hooks](./hooks.md)
+Optional hooks to dynamically modify requests and responses. See [Hooks](../hooks)

pkg/roles/dns/api_zones.go

@@ -16,11 +16,11 @@ type APIZonesGetInput struct {
 	Name string `query:"name"  description:"Optionally get DNS Zone by name"`
 }
 type APIZone struct {
-	Name           string              `json:"name" required:"true"`
-	HandlerConfigs []map[string]string `json:"handlerConfigs" required:"true"`
-	DefaultTTL     uint32              `json:"defaultTTL" required:"true"`
-	Authoritative  bool                `json:"authoritative" required:"true"`
-	Hook           string              `json:"hook" required:"true"`
+	Name           string                   `json:"name" required:"true"`
+	HandlerConfigs []map[string]interface{} `json:"handlerConfigs" required:"true"`
+	DefaultTTL     uint32                   `json:"defaultTTL" required:"true"`
+	Authoritative  bool                     `json:"authoritative" required:"true"`
+	Hook           string                   `json:"hook" required:"true"`
 }
 type APIZonesGetOutput struct {
 	Zones []APIZone `json:"zones" required:"true"`
@@ -73,11 +73,11 @@ func (r *Role) APIZonesGet() usecase.Interactor {
 }
 
 type APIZonesPutInput struct {
-	Name           string              `query:"zone" required:"true" maxLength:"255"`
-	HandlerConfigs []map[string]string `json:"handlerConfigs" required:"true"`
-	DefaultTTL     uint32              `json:"defaultTTL" required:"true"`
-	Authoritative  bool                `json:"authoritative" required:"true"`
-	Hook           string              `json:"hook" required:"true"`
+	Name           string                   `query:"zone" required:"true" maxLength:"255"`
+	HandlerConfigs []map[string]interface{} `json:"handlerConfigs" required:"true"`
+	DefaultTTL     uint32                   `json:"defaultTTL" required:"true"`
+	Authoritative  bool                     `json:"authoritative" required:"true"`
+	Hook           string                   `json:"hook" required:"true"`
 }
 
 func (r *Role) APIZonesPut() usecase.Interactor {

pkg/roles/dns/api_zones_test.go

@@ -44,7 +44,7 @@ func TestAPIZonesPut(t *testing.T) {
 	assert.NoError(t, role.APIZonesPut().Interact(ctx, dns.APIZonesPutInput{
 		Name:          strings.TrimSuffix(name, "."),
 		Authoritative: true,
-		HandlerConfigs: []map[string]string{
+		HandlerConfigs: []map[string]interface{}{
 			{
 				"type": "etcd",
 			},
@@ -61,7 +61,7 @@ func TestAPIZonesPut(t *testing.T) {
 		),
 		dns.Zone{
 			Authoritative: true,
-			HandlerConfigs: []map[string]string{
+			HandlerConfigs: []map[string]interface{}{
 				{
 					"type": "etcd",
 				},

pkg/roles/dns/handler.go

@@ -9,3 +9,26 @@ type Handler interface {
 	Handle(w *utils.FakeDNSWriter, r *utils.DNSRequest) *dns.Msg
 	Identifier() string
 }
+
+type HandlerConstructor func(z *Zone, rawConfig map[string]interface{}) Handler
+
+var HandlerRegistry = newRegistry()
+
+type handlerRegistry struct {
+	handlers map[string]HandlerConstructor
+}
+
+func newRegistry() handlerRegistry {
+	return handlerRegistry{
+		handlers: make(map[string]HandlerConstructor),
+	}
+}
+
+func (hn handlerRegistry) Add(identifier string, h HandlerConstructor) {
+	hn.handlers[identifier] = h
+}
+
+func (hn handlerRegistry) Find(identifier string) (HandlerConstructor, bool) {
+	c, ok := hn.handlers[identifier]
+	return c, ok
+}

pkg/roles/dns/handler_coredns.go

@@ -17,20 +17,26 @@ import (
 const CoreDNSType = "coredns"
 
 type CoreDNS struct {
-	c        map[string]string
+	c        map[string]interface{}
 	log      *zap.Logger
 	instance *caddy.Instance
 	srv      *dnsserver.Server
 }
 
-func NewCoreDNS(z *Zone, rawConfig map[string]string) *CoreDNS {
+func init() {
+	HandlerRegistry.Add(CoreDNSType, func(z *Zone, rawConfig map[string]interface{}) Handler {
+		return NewCoreDNS(z, rawConfig)
+	})
+}
+
+func NewCoreDNS(z *Zone, rawConfig map[string]interface{}) *CoreDNS {
 	core := &CoreDNS{
 		c: rawConfig,
 	}
 	core.log = z.log.With(zap.String("handler", core.Identifier()))
 	dnsserver.Quiet = true
 	corefile := caddy.CaddyfileInput{
-		Contents:       []byte(core.c["config"]),
+		Contents:       []byte(core.c["config"].(string)),
 		Filepath:       "in-memory",
 		ServerTypeName: "dns",
 	}

pkg/roles/dns/handler_coredns_test.go

@@ -32,7 +32,7 @@ func TestRoleDNSHandlerCoreDNS(t *testing.T) {
 			".",
 		).String(),
 		tests.MustJSON(dns.Zone{
-			HandlerConfigs: []map[string]string{
+			HandlerConfigs: []map[string]interface{}{
 				{
 					"type":   "coredns",
 					"config": CoreDNSConfig,

pkg/roles/dns/handler_etcd.go

@@ -20,7 +20,13 @@ type EtcdHandler struct {
 	lookupKey func(k *storage.Key, qname string, r *utils.DNSRequest) []dns.RR
 }
 
-func NewEtcdHandler(z *Zone, config map[string]string) *EtcdHandler {
+func init() {
+	HandlerRegistry.Add(EtcdType, func(z *Zone, rawConfig map[string]interface{}) Handler {
+		return NewEtcdHandler(z, rawConfig)
+	})
+}
+
+func NewEtcdHandler(z *Zone, config map[string]interface{}) *EtcdHandler {
 	eh := &EtcdHandler{
 		z: z,
 	}

pkg/roles/dns/handler_etcd_test.go

@@ -27,7 +27,7 @@ func TestRoleDNS_Etcd(t *testing.T) {
 			TestZone,
 		).String(),
 		tests.MustJSON(dns.Zone{
-			HandlerConfigs: []map[string]string{
+			HandlerConfigs: []map[string]interface{}{
 				{
 					"type": "etcd",
 				},
@@ -82,7 +82,7 @@ func TestRoleDNS_Etcd_Root(t *testing.T) {
 			TestZone,
 		).String(),
 		tests.MustJSON(dns.Zone{
-			HandlerConfigs: []map[string]string{
+			HandlerConfigs: []map[string]interface{}{
 				{
 					"type": "etcd",
 				},
@@ -136,7 +136,7 @@ func TestRoleDNS_Etcd_Wildcard(t *testing.T) {
 			TestZone,
 		).String(),
 		tests.MustJSON(dns.Zone{
-			HandlerConfigs: []map[string]string{
+			HandlerConfigs: []map[string]interface{}{
 				{
 					"type": "etcd",
 				},
@@ -190,7 +190,7 @@ func TestRoleDNS_Etcd_CNAME(t *testing.T) {
 			TestZone,
 		).String(),
 		tests.MustJSON(dns.Zone{
-			HandlerConfigs: []map[string]string{
+			HandlerConfigs: []map[string]interface{}{
 				{
 					"type": "etcd",
 				},
@@ -271,7 +271,7 @@ func TestRoleDNS_Etcd_WildcardNested(t *testing.T) {
 			TestZone,
 		).String(),
 		tests.MustJSON(dns.Zone{
-			HandlerConfigs: []map[string]string{
+			HandlerConfigs: []map[string]interface{}{
 				{
 					"type": "etcd",
 				},
@@ -325,7 +325,7 @@ func TestRoleDNS_Etcd_MixedCase(t *testing.T) {
 			"eXaMpLe.CoM.",
 		).String(),
 		tests.MustJSON(dns.Zone{
-			HandlerConfigs: []map[string]string{
+			HandlerConfigs: []map[string]interface{}{
 				{
 					"type": "etcd",
 				},
@@ -379,7 +379,7 @@ func TestRoleDNS_Etcd_MixedCase_Reverse(t *testing.T) {
 			TestZone,
 		).String(),
 		tests.MustJSON(dns.Zone{
-			HandlerConfigs: []map[string]string{
+			HandlerConfigs: []map[string]interface{}{
 				{
 					"type": "etcd",
 				},

pkg/roles/dns/handler_forward_blocky.go

@@ -24,13 +24,19 @@ const BlockyForwarderType = "forward_blocky"
 
 type BlockyForwarder struct {
 	*IPForwarderHandler
-	c   map[string]string
+	c   map[string]interface{}
 	b   *server.Server
 	log *zap.Logger
 	st  time.Time
 	cfg *config.Config
 }
 
+func init() {
+	HandlerRegistry.Add(BlockyForwarderType, func(z *Zone, rawConfig map[string]interface{}) Handler {
+		return NewBlockyForwarder(z, rawConfig)
+	})
+}
+
 func HTTPByteSource(url string) config.BytesSource {
 	return config.BytesSource{
 		Type: config.BytesSourceTypeHttp,
@@ -45,7 +51,7 @@ func TextByteSource(content string) config.BytesSource {
 	}
 }
 
-func NewBlockyForwarder(z *Zone, rawConfig map[string]string) *BlockyForwarder {
+func NewBlockyForwarder(z *Zone, rawConfig map[string]interface{}) *BlockyForwarder {
 	bfwd := &BlockyForwarder{
 		IPForwarderHandler: NewIPForwarderHandler(z, rawConfig),
 		c:                  rawConfig,
@@ -80,7 +86,17 @@ func (bfwd *BlockyForwarder) Identifier() string {
 }
 
 func (bfwd *BlockyForwarder) getConfig() (*config.Config, error) {
-	forwarders := strings.Split(bfwd.c["to"], ";")
+	forwarders := []string{}
+	switch v := bfwd.c["to"].(type) {
+	case string:
+		forwarders = strings.Split(v, ";")
+	case []interface{}:
+		for _, fwd := range v {
+			if f, ok := fwd.(string); ok {
+				forwarders = append(forwarders, f)
+			}
+		}
+	}
 	upstreams := make([]config.Upstream, len(forwarders))
 	for idx, fwd := range forwarders {
 		us, err := config.ParseUpstream(fwd)
@@ -163,10 +179,20 @@ func (bfwd *BlockyForwarder) getConfig() (*config.Config, error) {
 	return &cfg, nil
 }
 
-func (bfwd *BlockyForwarder) getLists(raw string) []config.BytesSource {
+func (bfwd *BlockyForwarder) getLists(raw interface{}) []config.BytesSource {
 	list := []config.BytesSource{}
-	lists := strings.Split(raw, ";")
-	for _, rl := range lists {
+	rawLists := []string{}
+	switch v := raw.(type) {
+	case string:
+		rawLists = strings.Split(v, ";")
+	case []interface{}:
+		for _, rl := range v {
+			if r, ok := rl.(string); ok {
+				rawLists = append(rawLists, r)
+			}
+		}
+	}
+	for _, rl := range rawLists {
 		if strings.HasPrefix(rl, "http") {
 			list = append(list, HTTPByteSource(rl))
 		} else {

pkg/roles/dns/handler_forward_blocky_test.go

@@ -34,7 +34,7 @@ func TestRoleDNS_BlockyForwarder(t *testing.T) {
 			".",
 		).String(),
 		tests.MustJSON(dns.Zone{
-			HandlerConfigs: []map[string]string{
+			HandlerConfigs: []map[string]interface{}{
 				{
 					"type":       "forward_blocky",
 					"blocklists": "http://127.0.0.1:9005/blocky_file.txt",
@@ -83,7 +83,7 @@ func TestRoleDNS_BlockyForwarder_Allow(t *testing.T) {
 			".",
 		).String(),
 		tests.MustJSON(dns.Zone{
-			HandlerConfigs: []map[string]string{
+			HandlerConfigs: []map[string]interface{}{
 				{
 					"type":       "forward_blocky",
 					"blocklists": "http://127.0.0.1:9005/blocky_file.txt",