feat: host-based routing in proxy

internal/spec/proxy/schema.json

@@ -14,11 +14,23 @@
                         "address": {
                             "type": "string"
                         },
-                        "target": {
-                            "type": "string"
+                        "mappings": {
+                            "type": "array",
+                            "items": {
+                                "type": "object",
+                                "properties": {
+                                    "hostPattern": {
+                                        "type": "string"
+                                    },
+                                    "target": {
+                                        "type": "string"
+                                    }
+                                },
+                                "required": ["hostPattern", "target"]
+                            }
                         }
                     },
-                    "required": ["address", "target"],
+                    "required": ["address", "mappings"],
                     "additionalProperties": false
                 }
             }

internal/spec/proxy/spec.go

@@ -12,8 +12,13 @@ type Spec struct {
 }
 
 type ProxyEntry struct {
-	Address string `json:"address"`
-	Target  string `json:"target"`
+	Address  string         `json:"address"`
+	Mappings []ProxyMapping `json:"mappings"`
+}
+
+type ProxyMapping struct {
+	HostPattern string `json:"hostPattern"`
+	Target      string `json:"target"`
 }
 
 func (s *Spec) SpecName() spec.Name {

internal/spec/proxy/testdata/spec-additional-prop.json

@@ -4,7 +4,12 @@
       "proxies": {
         "cadoles.com": {
           "address": ":3003",
-          "target": "https://www.cadoles.com",
+          "mappings": [
+            {
+              "hostPattern": "localhost:3003",
+              "target": "https://www.cadoles.com" 
+            }
+          ],
           "foo": "bar"
         }
       }

internal/spec/proxy/testdata/spec-ok.json

@@ -4,7 +4,12 @@
       "proxies": {
         "cadoles.com": {
           "address": ":3003",
-          "target": "https://www.cadoles.com"
+          "mappings": [
+            {
+              "hostPattern": "localhost:3003",
+              "target": "https://www.cadoles.com" 
+            }
+          ]
         }
       }
     },