Split implementations from generic code

controllers/nginx/pkg/template/configmap.go

@@ -0,0 +1,122 @@
+/*
+Copyright 2015 The Kubernetes 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 template
+
+import (
+	"strconv"
+	"strings"
+
+	"github.com/golang/glog"
+	"github.com/imdario/mergo"
+
+	"github.com/fatih/structs"
+	"github.com/mitchellh/mapstructure"
+	go_camelcase "github.com/segmentio/go-camelcase"
+
+	"k8s.io/ingress/controllers/nginx/pkg/config"
+	"k8s.io/ingress/core/pkg/ingress/defaults"
+
+	"k8s.io/kubernetes/pkg/api"
+)
+
+const (
+	customHTTPErrors     = "custom-http-errors"
+	skipAccessLogUrls    = "skip-access-log-urls"
+	whitelistSourceRange = "whitelist-source-range"
+)
+
+// StandarizeKeyNames ...
+func StandarizeKeyNames(data interface{}) map[string]interface{} {
+	return fixKeyNames(structs.Map(data))
+}
+
+// ReadConfig obtains the configuration defined by the user merged with the defaults.
+func ReadConfig(conf *api.ConfigMap) config.Configuration {
+	if len(conf.Data) == 0 {
+		return config.NewDefault()
+	}
+
+	var errors []int
+	var skipUrls []string
+	var whitelist []string
+
+	if val, ok := conf.Data[customHTTPErrors]; ok {
+		delete(conf.Data, customHTTPErrors)
+		for _, i := range strings.Split(val, ",") {
+			j, err := strconv.Atoi(i)
+			if err != nil {
+				glog.Warningf("%v is not a valid http code: %v", i, err)
+			} else {
+				errors = append(errors, j)
+			}
+		}
+	}
+	if val, ok := conf.Data[skipAccessLogUrls]; ok {
+		delete(conf.Data, skipAccessLogUrls)
+		skipUrls = strings.Split(val, ",")
+	}
+	if val, ok := conf.Data[whitelistSourceRange]; ok {
+		delete(conf.Data, whitelistSourceRange)
+		whitelist = append(whitelist, strings.Split(val, ",")...)
+	}
+
+	to := config.Configuration{}
+	to.Backend = defaults.Backend{
+		CustomHTTPErrors:     filterErrors(errors),
+		SkipAccessLogURLs:    skipUrls,
+		WhitelistSourceRange: whitelist,
+	}
+	def := config.NewDefault()
+	if err := mergo.Merge(&to, def); err != nil {
+		glog.Warningf("unexpected error merging defaults: %v", err)
+	}
+
+	metadata := &mapstructure.Metadata{}
+	decoder, err := mapstructure.NewDecoder(&mapstructure.DecoderConfig{
+		TagName:          "structs",
+		Result:           &to,
+		WeaklyTypedInput: true,
+		Metadata:         metadata,
+	})
+
+	err = decoder.Decode(conf.Data)
+	if err != nil {
+		glog.Infof("%v", err)
+	}
+	return to
+}
+
+func filterErrors(codes []int) []int {
+	var fa []int
+	for _, code := range codes {
+		if code > 299 && code < 600 {
+			fa = append(fa, code)
+		} else {
+			glog.Warningf("error code %v is not valid for custom error pages", code)
+		}
+	}
+
+	return fa
+}
+
+func fixKeyNames(data map[string]interface{}) map[string]interface{} {
+	fixed := make(map[string]interface{})
+	for k, v := range data {
+		fixed[go_camelcase.Camelcase(k)] = v
+	}
+	return fixed
+}