| // Licensed to Apache Software Foundation (ASF) under one or more contributor |
| // license agreements. See the NOTICE file distributed with |
| // this work for additional information regarding copyright |
| // ownership. Apache Software Foundation (ASF) licenses this file to you 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 config |
| |
| import ( |
| "os" |
| "regexp" |
| "strconv" |
| "strings" |
| |
| "github.com/spf13/viper" |
| ) |
| |
| // ${ENV:defaultVal} pattern is supported to override the default value by the env config. |
| // And the value would be converted to the different types, such as int, float64 ana string. |
| // If you want to keep it as the string value, please decorate it with `"`. |
| const RegularExpression = "${_|[A-Z]+:.*}" |
| |
| func overrideConfigByEnv(v *viper.Viper) error { |
| regex, err := regexp.Compile(RegularExpression) |
| if err != nil { |
| return err |
| } |
| overrideCfg := overrideMapStringInterface(v.AllSettings(), regex) |
| for key, val := range overrideCfg { |
| v.Set(key, val) |
| } |
| return nil |
| } |
| |
| func overrideMapStringInterface(cfg map[string]interface{}, regex *regexp.Regexp) map[string]interface{} { |
| res := make(map[string]interface{}) |
| for key, val := range cfg { |
| switch val := val.(type) { |
| case string: |
| res[key] = overrideString(val, regex) |
| case []interface{}: |
| res[key] = overrideSlice(val, regex) |
| case map[string]interface{}: |
| res[key] = overrideMapStringInterface(val, regex) |
| case map[interface{}]interface{}: |
| res[key] = overrideMapInterfaceInterface(val, regex) |
| default: |
| res[key] = val |
| } |
| } |
| return res |
| } |
| |
| func overrideSlice(m []interface{}, regex *regexp.Regexp) []interface{} { |
| res := make([]interface{}, 0) |
| for _, val := range m { |
| switch val := val.(type) { |
| case map[string]interface{}: |
| res = append(res, overrideMapStringInterface(val, regex)) |
| case map[interface{}]interface{}: |
| res = append(res, overrideMapInterfaceInterface(val, regex)) |
| case string: |
| res = append(res, val) |
| } |
| } |
| return res |
| } |
| |
| func overrideMapInterfaceInterface(m map[interface{}]interface{}, regex *regexp.Regexp) interface{} { |
| cfg := make(map[string]interface{}) |
| for key, val := range m { |
| cfg[key.(string)] = val |
| } |
| return overrideMapStringInterface(cfg, regex) |
| } |
| |
| func overrideString(s string, regex *regexp.Regexp) interface{} { |
| if regex.MatchString(s) { |
| index := strings.Index(s, ":") |
| envName := s[2:index] |
| defaultVal := s[index+1 : len(s)-1] |
| envVal := os.Getenv(envName) |
| if envVal != "" { |
| defaultVal = envVal |
| } |
| return parseVal(defaultVal) |
| } |
| return s |
| } |
| |
| func parseVal(val string) interface{} { |
| if intVal, err := strconv.Atoi(val); err == nil { |
| return intVal |
| } else if floatVal, err := strconv.ParseFloat(val, 64); err == nil { |
| return floatVal |
| } else if strings.EqualFold(val, "true") { |
| return true |
| } else if strings.EqualFold(val, "false") { |
| return false |
| } else if strings.HasPrefix(val, "\"") && strings.HasSuffix(val, "\"") { |
| return val[1 : len(val)-1] |
| } else { |
| return val |
| } |
| } |