update doc

README.md

@@ -3,3 +3,43 @@
 [![Coverage Status](https://coveralls.io/repos/github/DavidCai1993/fresh/badge.svg?branch=master)](https://coveralls.io/github/DavidCai1993/fresh?branch=master)
 
 HTTP response freshness testing for Go
+
+## Installation
+
+```sh
+go get -u github.com/go-http-utils/fresh
+```
+
+## Documentation
+
+API documentation can be found here: https://godoc.org/github.com/go-http-utils/fresh
+
+## Usage
+
+```go
+import (
+  "net/http"
+
+  "github.com/go-http-utils/fresh"
+)
+```
+
+```go
+reqHeader, resHeader := make(http.Header), make(http.Header)
+
+reqHeader.Set("if-none-match", "foo")
+resHeader.Set("etag", "bar")
+
+fresh.IsFresh(reqHeader, resHeader)
+// -> false
+```
+
+```go
+reqHeader, resHeader := make(http.Header), make(http.Header)
+
+reqHeader.Set("if-modified-since", "Mon, 14 Nov 2016 22:05:49 GMT")
+resHeader.Set("last-modified", "Mon, 14 Nov 2016 22:05:47 GMT")
+
+fresh.IsFresh(reqHeader, resHeader)
+// -> true
+```

doc.go

@@ -0,0 +1,25 @@
+// Package fresh is used to check whether cache can be used in this HTTP request.
+//
+// ----------------------------------------------------------------
+//
+// reqHeader, resHeader := make(http.Header), make(http.Header)
+//
+// reqHeader.Set("if-none-match", "foo")
+// resHeader.Set("etag", "bar")
+
+// fresh.IsFresh(reqHeader, resHeader)
+// // -> false
+//
+// ----------------------------------------------------------------
+//
+// reqHeader, resHeader := make(http.Header), make(http.Header)
+
+// reqHeader.Set("if-modified-since", "Mon, 14 Nov 2016 22:05:49 GMT")
+// resHeader.Set("last-modified", "Mon, 14 Nov 2016 22:05:47 GMT")
+
+// fresh.IsFresh(reqHeader, resHeader)
+// // -> true
+//
+// ----------------------------------------------------------------
+
+package fresh

example_test.go

@@ -0,0 +1,26 @@
+package fresh_test
+
+import (
+	"fmt"
+	"net/http"
+
+	"github.com/go-http-utils/fresh"
+)
+
+func ExampleFresh_IsFresh() {
+	reqHeader, resHeader := make(http.Header), make(http.Header)
+
+	reqHeader.Set("if-none-match", "foo")
+	resHeader.Set("etag", "bar")
+
+	fmt.Println(fresh.IsFresh(reqHeader, resHeader))
+	// -> false
+
+	reqHeader, resHeader = make(http.Header), make(http.Header)
+
+	reqHeader.Set("if-modified-since", "Mon, 14 Nov 2016 22:05:49 GMT")
+	resHeader.Set("last-modified", "Mon, 14 Nov 2016 22:05:47 GMT")
+
+	fmt.Println(fresh.IsFresh(reqHeader, resHeader))
+	// -> true
+}

fresh.go

@@ -7,7 +7,7 @@ import (
 )
 
 // Version is this package's verison
-const Version = "0.0.2"
+const Version = "0.1.0"
 
 // HTTP header fileds
 const (