Package configure 能够监控，读取符合格式的配置文件并转换为层次 <key, value> pair，在程序中被调用.
设计报告: https://github.com/BOBBAIcloudwithpants/configure/blob/master/specification.md
API 文档: https://github.com/BOBBAIcloudwithpants/configure/wiki/Configure-API-Document
- 解析配置文件为配置对象
- 从配置对象中读取配置项
- 监听配置文件的改动，在不符合格式时在
stderr中输出错误信息，方便用户作出配置文件的格式调整
- go 1.14+
go get -u github.com/bobbaicloudwithpants/configure
configure 目前仅支持下面的配置文件格式：
- linux/macOS 下:
[section_name1]
# description
# of
# key-value 1
key1 = val1
# description of key-value 2
key2 = val2
[section_name2]
# description of key-value3
key3 = val3
- Windows 下:
[section_name1]
; description
; of
; key-value 1
key1 = val1
; description of key-value 2
key2 = val2
[section_name2]
; description of key-value3
key3 = val3
- Example:
# possible values : production, development
app_mode = development
[paths]
# Path to where grafana can store temp files, sessions, and the sqlite3 db (if that is used)
data = /home/git/grafana
[server]
# Protocol (http or https)
protocol = http
# The http port to use
http_port = 9999
# Redirect to correct domain if host header does not match domain
# Prevents DNS rebinding attacks
enforce_domain = true
package main
import (
"fmt"
"gitee.com/baijiadong/service_computing/hw4/configure"
"log"
)
func defaultListen(filepath string) {
log.Println(fmt.Sprintf("file '%s' has been changed", filepath))
}
func main() {
file, err := configure.Watch("test.txt", defaultListen)
if err == nil {
// 输出：test.txt
fmt.Println(file.Filename())
// 输出：http
fmt.Println(file.Section("server").Key("protocol").Val())
// 输出: possible values : production, development
// 这里，由于 'app_mode' 不属于任何分区，因此被解析到 default 分区中
// default 分区通过 file.Section("") 或者 filt.Section("default") 来获取
fmt.Println(file.Section("").Key("app_mode").Description())
} else {
configure.LogError(err)
}
}假设此时配置文件被修改成如下的内容:
# possible values : production, development
app_mode = development
[paths]
# Path to where grafana can store temp files, sessions, and the sqlite3 db (if that is used)
data= /home/git/grafana
[server]
# Protocol (hdddgggttp or https)
protocol = http
可以看到，这个文件的 第6行, 即 data= /home/git/grafana 是不符合格式的，因为 = 两侧应当都有且仅有一个空格，然后我们运行下面的代码:
package main
import (
"fmt"
"github.com/bobbaicloudwithpants/configure" // import 配置包
)
func defaultListen(filepath string) {
log.Println(fmt.Sprintf("file '%s' has been changed", filepath))
}
func main() {
// 假设当前目录下已经存在名为 test.txt 的配置文件，配置文件的内容与上面的 Example 相同
file, err := configure.Watch("test.txt", defaultListen)
if err == nil {
// 输出：test.txt
fmt.Println(file.Filename())
} else {
configure.LogError(err)
}
}控制台会出现如下输出:
2020/10/16 16:56:23 You have unrecognized format in config file 'test.txt', sentence: 'data= /home/git/grafana'
同时，进程在 Watch 函数被阻塞，这是因为配置文件格式并不正确，需要改成正确的格式才能正常进行。于是我们修改文件为如下:
# possible values : production, development
app_mode = development
[paths]
# Path to where grafana can store temp files, sessions, and the sqlite3 db (if that is used)
data = /home/git/grafana
[server]
# Protocol (hdddgggttp or https)
protocol = http
保存修改之后，控制台出现如下的输出:
2020/10/16 16:57:31 file 'test.txt' has been changed
并且进程不再被阻塞。
假设此时的目录下有一个文件名为 example2.txt ，内容为:
# possible values : production, development app_mode = development [paths] # Path to where grafana can store temp files, sessions, and the sqlite3 db (if that is used) data = /home/git/grafana [server] # Protocol (http or https) protocol = http # The http port to use http_port = 9999 # Redirect to correct domain if host header does not match domain # Prevents DNS rebinding attacks enforce_domain = true
那么通过下面的代码:
package main
import (
"fmt"
"github.com/bobbaicloudwithpants/configure"// import 配置包
"log"
)
func defaultListen(filepath string) {
log.Println(fmt.Sprintf("file '%s' has been changed", filepath))
}
func main() {
// 将分隔符定义为 "\t"
file, err := configure.WatchWithOption("example2.txt", defaultListen, configure.Option{Separation: "\t"})
if err == nil {
// 输出：example2.txt
fmt.Println(file.Filename())
} else {
configure.LogError(err)
}
}同样能够正常解析配置项。