From daccb8b4639600075483151fc6906f46f980a838 Mon Sep 17 00:00:00 2001
From: Gregory Eremin <g@erem.in>
Date: Sat, 29 Aug 2015 20:37:21 +0300
Subject: [PATCH] Add readme

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 README.md | 110 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 110 insertions(+)
 create mode 100644 README.md

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+# Secondly
+
+Secondly is a configuration manager plugin for Go projects. It taks care of
+the app's configuration, specifically of updating it in runtime.
+
+## Configuration
+
+First we need to define a struct that will hold app's configuration. Let's make
+it simple for demostration purposes.
+
+```go
+type Config struct {
+    AppName string  `json:"app_name"`
+    Version float32 `json:"version"`
+}
+```
+
+Make sure you've defined `json` tags on each field.
+
+Next, right where you will define your app's flags ask Secondly to add one for
+configuration file.
+
+```go
+secondly.SetupFlags()
+flag.Parse()
+```
+
+Now you can pass a configuration file to your program like this:
+
+```
+./app -config=config.json
+```
+
+Now we need to ask Secondly to take care of your configuration:
+
+```go
+var conf Config
+secondly.Manage(&conf)
+```
+
+You'll probably want to know when configuration is loaded, so there's a handly
+helper function just for that:
+
+```go
+secondly.OnLoad(func(){
+    log.Println("Configuration initialized")
+})
+```
+
+Congratulations! You've just configured Secondly to read and initialize the
+configuration of your app. But this is not what you came for, right?
+
+If you want a configuration GUI, simply start Secondly's web server on a port
+you want.
+
+```
+secondly.StartServer("", 5500)
+```
+
+Tired of restarting the app every time you modify the config? You're not alone.
+
+```go
+secondly.HandleFSEvents()
+```
+
+Want some more control over when specifically the config will be reloaded? Ask
+Secondly to listen for SIGHUP syscalls.
+
+```go
+secondly.HandleSIGHUP()
+```
+
+You can also set up callback functions on specific fields and receive a call
+when this fields value changes.
+
+```go
+secondly.OnChange("NumWorkers", func(oldVal, newVal interface{}) {
+    old := oldVal.(int)
+    cur := newVal.(int)
+    if cur > old {
+        pool.AddWorkers(cur - old)
+    } else {
+        pool.StopWorkers(old - cur)
+    }
+    log.Println("Number of workers changed from %d to %d", old, cur)
+}
+})
+```
+
+Full example can be found [here](https://github.com/localhots/secondly/blob/master/demo/demo.go).
+
+## Demo Screenshot
+
+<img src="https://raw.githubusercontent.com/localhots/secondly/master/demo/demo.png" width="440">
+
+## Building
+
+The only thing to keep in mind when building Secndly is to convert assets into a
+binary form so they could be kept in memory of your app and would not require
+any additional web server configuration.
+
+```
+go get github.com/GeertJohan/go.rice/rice
+rice embed-go
+go build
+```
+
+## Licence
+
+Secondly is distributed under the [MIT Licence](https://github.com/localhots/secondly/blob/master/LICENCE).