1 files changed, 113 insertions, 0 deletions
diff --git a/caddyconfig/configadapters.go b/caddyconfig/configadapters.go
new file mode 100644
index 0000000..6e5d530
--- /dev/null
+++ b/caddyconfig/configadapters.go
@@ -0,0 +1,113 @@
+// Copyright 2015 Matthew Holt and The Caddy Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package caddyconfig
+
+import (
+	"encoding/json"
+	"fmt"
+)
+
+// Adapter is a type which can adapt a configuration to Caddy JSON.
+// It returns the results and any warnings, or an error.
+type Adapter interface {
+	Adapt(body []byte, options map[string]string) ([]byte, []Warning, error)
+}
+
+// Warning represents a warning or notice related to conversion.
+type Warning struct {
+	File      string
+	Line      int
+	Directive string
+	Message   string
+}
+
+// JSON encodes val as JSON, returning it as a json.RawMessage. Any
+// marshaling errors (which are highly unlikely with correct code)
+// are converted to warnings. This is convenient when filling config
+// structs that require a json.RawMessage, without having to worry
+// about errors.
+func JSON(val interface{}, warnings *[]Warning) json.RawMessage {
+	b, err := json.Marshal(val)
+	if err != nil {
+		if warnings != nil {
+			*warnings = append(*warnings, Warning{Message: err.Error()})
+		}
+		return nil
+	}
+	return b
+}
+
+// JSONModuleObject is like JSON, except it marshals val into a JSON object
+// and then adds a key to that object named fieldName with the value fieldVal.
+// This is useful for JSON-encoding module values where the module name has to
+// be described within the object by a certain key; for example,
+// "responder": "file_server" for a file server HTTP responder. The val must
+// encode into a map[string]interface{} (i.e. it must be a struct or map),
+// and any errors are converted into warnings, so this can be conveniently
+// used when filling a struct. For correct code, there should be no errors.
+func JSONModuleObject(val interface{}, fieldName, fieldVal string, warnings *[]Warning) json.RawMessage {
+	// encode to a JSON object first
+	enc, err := json.Marshal(val)
+	if err != nil {
+		if warnings != nil {
+			*warnings = append(*warnings, Warning{Message: err.Error()})
+		}
+		return nil
+	}
+
+	// then decode the object
+	var tmp map[string]interface{}
+	err = json.Unmarshal(enc, &tmp)
+	if err != nil {
+		if warnings != nil {
+			*warnings = append(*warnings, Warning{Message: err.Error()})
+		}
+		return nil
+	}
+
+	// so we can easily add the module's field with its appointed value
+	tmp[fieldName] = fieldVal
+
+	// then re-marshal as JSON
+	result, err := json.Marshal(tmp)
+	if err != nil {
+		if warnings != nil {
+			*warnings = append(*warnings, Warning{Message: err.Error()})
+		}
+		return nil
+	}
+
+	return result
+}
+
+// JSONIndent is used to JSON-marshal the final resulting Caddy
+// configuration in a consistent, human-readable way.
+func JSONIndent(val interface{}) ([]byte, error) {
+	return json.MarshalIndent(val, "", "\t")
+}
+
+func RegisterAdapter(name string, adapter Adapter) error {
+	if _, ok := configAdapters[name]; ok {
+		return fmt.Errorf("%s: already registered", name)
+	}
+	configAdapters[name] = adapter
+	return nil
+}
+
+func GetAdapter(name string) Adapter {
+	return configAdapters[name]
+}
+
+var configAdapters = make(map[string]Adapter)