update readme and add example

* dcca987 add an old example and a basic one

examples/blog/blog.go

@@ -0,0 +1,81 @@
+package main
+
+import (
+	"database/sql"
+	"encoding/json"
+	"net/http"
+)
+
+type api struct {
+	db *sql.DB
+}
+
+type post struct {
+	ID    int
+	Title string
+	Body  string
+}
+
+func (a *api) posts(w http.ResponseWriter, r *http.Request) {
+	rows, err := a.db.Query("SELECT id, title, body FROM posts")
+	if err != nil {
+		a.fail(w, "failed to fetch posts: "+err.Error(), 500)
+		return
+	}
+	defer rows.Close()
+
+	var posts []*post
+	for rows.Next() {
+		p := &post{}
+		if err := rows.Scan(&p.ID, &p.Title, &p.Body); err != nil {
+			a.fail(w, "failed to scan post: "+err.Error(), 500)
+			return
+		}
+		posts = append(posts, p)
+	}
+	if rows.Err() != nil {
+		a.fail(w, "failed to read all posts: "+rows.Err().Error(), 500)
+		return
+	}
+
+	data := struct {
+		Posts []*post
+	}{posts}
+
+	a.ok(w, data)
+}
+
+func main() {
+	// @NOTE: the real connection is not required for tests
+	db, err := sql.Open("mysql", "root@/blog")
+	if err != nil {
+		panic(err)
+	}
+	app := &api{db: db}
+	http.HandleFunc("/posts", app.posts)
+	http.ListenAndServe(":8080", nil)
+}
+
+func (a *api) fail(w http.ResponseWriter, msg string, status int) {
+	w.Header().Set("Content-Type", "application/json")
+
+	data := struct {
+		Error string
+	}{Error: msg}
+
+	resp, _ := json.Marshal(data)
+	w.WriteHeader(status)
+	w.Write(resp)
+}
+
+func (a *api) ok(w http.ResponseWriter, data interface{}) {
+	w.Header().Set("Content-Type", "application/json")
+
+	resp, err := json.Marshal(data)
+	if err != nil {
+		w.WriteHeader(http.StatusInternalServerError)
+		a.fail(w, "oops something evil has happened", 500)
+		return
+	}
+	w.Write(resp)
+}