reorganizing server-related packages

src/server/router/context.go

@@ -0,0 +1,61 @@
+package router
+
+import (
+	"encoding/json"
+	"fmt"
+	"html/template"
+	"log"
+	"net/http"
+	"strconv"
+)
+
+type Context struct {
+	Req *http.Request
+	Out http.ResponseWriter
+
+	Vars map[string]string
+
+	chain []Handler
+	index int
+}
+
+func (c *Context) Next() {
+	c.index++
+	c.chain[c.index](c)
+}
+
+func (c *Context) JSON(status int, data interface{}) {
+	body, err := json.Marshal(data)
+	if err != nil {
+		log.Fatal(err)
+	}
+	c.Out.WriteHeader(status)
+	c.Out.Header().Set("Content-Type", "application/json; charset=utf-8")
+	c.Out.Write(body)
+	c.Out.Write([]byte("\n"))
+}
+
+func (c *Context) HTML(status int, tmpl *template.Template, data interface{}) {
+	c.Out.WriteHeader(status)
+	c.Out.Header().Set("Content-Type", "text/html")
+	tmpl.Execute(c.Out, data)
+}
+
+func (c *Context) VarInt64(key string) (int64, error) {
+	if val, ok := c.Vars[key]; ok {
+		return strconv.ParseInt(val, 10, 64)
+	}
+	return 0, fmt.Errorf("no such var: %s", key)
+}
+
+func (c *Context) QueryInt64(key string) (int64, error) {
+	query := c.Req.URL.Query()
+	return strconv.ParseInt(query.Get(key), 10, 64)
+}
+
+func (c *Context) Redirect(url string) {
+	if url == "" {
+		url = "/"
+	}
+	http.Redirect(c.Out, c.Req, url, http.StatusFound)
+}

src/server/router/match.go

@@ -0,0 +1,24 @@
+package router
+
+import "regexp"
+
+func regexGroups(input string, regex *regexp.Regexp) map[string]string {
+	groups := make(map[string]string)
+	matches := regex.FindStringSubmatchIndex(input)
+	for i, key := range regex.SubexpNames()[1:] {
+		groups[key] = input[matches[i*2+2]:matches[i*2+3]]
+	}
+	return groups
+}
+
+func routeRegexp(route string) *regexp.Regexp {
+	chunks := regexp.MustCompile(`[\*\:]\w+`)
+	output := chunks.ReplaceAllStringFunc(route, func(m string) string {
+		if m[0:1] == `*` {
+			return "(?P<" + m[1:] + ">.+)"
+		}
+		return "(?P<" + m[1:] + ">[^/]+)"
+	})
+	output = "^" + output + "$"
+	return regexp.MustCompile(output)
+}

src/server/router/match_test.go

@@ -0,0 +1,76 @@
+package router
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestRouteRegexpPart(t *testing.T) {
+	in := "/hello/:world"
+	re := routeRegexp(in)
+
+	pos := []string{
+		"/hello/world",
+		"/hello/1234",
+		"/hello/bbc1",
+	}
+	for _, c := range pos {
+		if !re.MatchString(c) {
+			t.Errorf("%v must match %v", in, c)
+		}
+	}
+
+	neg := []string{
+		"/hello",
+		"/hello/world/",
+		"/sub/hello/123",
+		"//hello/123",
+		"/hello/123/hello/",
+	}
+	for _, c := range neg {
+		if re.MatchString(c) {
+			t.Errorf("%q must not match %q", in, c)
+		}
+	}
+}
+
+func TestRouteRegexpStar(t *testing.T) {
+	in := "/hello/*world"
+	re := routeRegexp(in)
+
+	pos := []string{"/hello/world", "/hello/world/test"}
+	for _, c := range pos {
+		if !re.MatchString(c) {
+			t.Errorf("%q must match %q", in, c)
+		}
+	}
+
+	neg := []string{"/hello/", "/hello"}
+	for _, c := range neg {
+		if re.MatchString(c) {
+			t.Errorf("%v must not match %v", in, c)
+		}
+	}
+}
+
+func TestRegexGroupsPart(t *testing.T) {
+	re := routeRegexp("/foo/:bar/1/:baz")
+
+	expect := map[string]string{"bar": "one", "baz": "two"}
+	actual := regexGroups("/foo/one/1/two", re)
+
+	if !reflect.DeepEqual(expect, actual) {
+		t.Errorf("expected: %q, actual: %q", expect, actual)
+	}
+}
+
+func TestRegexGroupsStar(t *testing.T) {
+	re := routeRegexp("/foo/*bar")
+
+	expect := map[string]string{"bar": "bar/baz/"}
+	actual := regexGroups("/foo/bar/baz/", re)
+
+	if !reflect.DeepEqual(expect, actual) {
+		t.Errorf("expected: %q, actual: %q", expect, actual)
+	}
+}

src/server/router/router.go

@@ -0,0 +1,73 @@
+package router
+
+import (
+	"net/http"
+	"regexp"
+	"strings"
+)
+
+type Handler func(*Context)
+
+type Router struct {
+	middle []Handler
+	routes []Route
+	base   string
+}
+
+type Route struct {
+	regex *regexp.Regexp
+	chain []Handler
+}
+
+func NewRouter(base string) *Router {
+	router := &Router{}
+	router.middle = make([]Handler, 0)
+	router.routes = make([]Route, 0)
+	router.base = base
+	return router
+}
+
+func (r *Router) Use(h Handler) {
+	r.middle = append(r.middle, h)
+}
+
+func (r *Router) For(path string, handler Handler) {
+	x := Route{}
+	x.regex = routeRegexp(path)
+	x.chain = append(r.middle, handler)
+
+	r.routes = append(r.routes, x)
+}
+
+func (r *Router) resolve(path string) *Route {
+	for _, route := range r.routes {
+		if route.regex.MatchString(path) {
+			return &route
+		}
+	}
+	return nil
+}
+
+func (r *Router) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
+	// autoclose open base url
+	if r.base != "" && r.base == req.URL.Path {
+		http.Redirect(rw, req, r.base+"/", http.StatusFound)
+		return
+	}
+
+	path := strings.TrimPrefix(req.URL.Path, r.base)
+
+	route := r.resolve(path)
+	if route == nil {
+		rw.WriteHeader(http.StatusNotFound)
+		return
+	}
+
+	context := &Context{}
+	context.Req = req
+	context.Out = rw
+	context.Vars = regexGroups(path, route.regex)
+	context.index = -1
+	context.chain = route.chain
+	context.Next()
+}

src/server/router/router_test.go

@@ -0,0 +1,147 @@
+package router
+
+import (
+	"io"
+	"net/http/httptest"
+	"testing"
+)
+
+func TestRouter(t *testing.T) {
+	middlecalled := false
+	router := NewRouter("")
+	router.Use(func(c *Context) {
+		middlecalled = true
+		c.Next()
+	})
+	router.For("/hello/:place", func(c *Context) {
+		c.Out.Write([]byte(c.Vars["place"]))
+	})
+
+	recorder := httptest.NewRecorder()
+	request := httptest.NewRequest("GET", "/hello/world", nil)
+	router.ServeHTTP(recorder, request)
+	body, _ := io.ReadAll(recorder.Result().Body)
+
+	if !middlecalled {
+		t.Error("middleware not called")
+	}
+	if recorder.Result().StatusCode != 200 {
+		t.Error("expected 200")
+	}
+	if string(body) != "world" {
+		t.Errorf("invalid response body, got %#v", body)
+	}
+}
+
+func TestRouterPaths(t *testing.T) {
+	router := NewRouter("")
+	router.For("/path/to/foo", func(c *Context) {
+		c.Out.Write([]byte("foo"))
+	})
+	router.For("/path/to/bar", func(c *Context) {
+		c.Out.Write([]byte("bar"))
+	})
+
+	recorder := httptest.NewRecorder()
+	request := httptest.NewRequest("GET", "/path/to/bar", nil)
+	router.ServeHTTP(recorder, request)
+
+	body, _ := io.ReadAll(recorder.Result().Body)
+	if string(body) != "bar" {
+		t.Error("expected 2nd route to be called")
+	}
+}
+
+func TestRouterMiddlewareIntercept(t *testing.T) {
+	router := NewRouter("")
+	router.Use(func(c *Context) {
+		c.Out.WriteHeader(404)
+	})
+	router.For("/hello/:place", func(c *Context) {
+		c.Out.WriteHeader(200)
+		c.Out.Write([]byte(c.Vars["place"]))
+	})
+
+	recorder := httptest.NewRecorder()
+	request := httptest.NewRequest("GET", "/hello/world", nil)
+
+	router.ServeHTTP(recorder, request)
+
+	if recorder.Result().StatusCode != 404 {
+		t.Error("expected 404")
+	}
+	body, _ := io.ReadAll(recorder.Result().Body)
+	if len(body) != 0 {
+		t.Errorf("expected empty body, got %v", body)
+	}
+}
+
+func TestRouterMiddlewareOrder(t *testing.T) {
+	router := NewRouter("")
+
+	router.Use(func(c *Context) {
+		c.Out.Write([]byte("foo"))
+		c.Next()
+	})
+	router.Use(func(c *Context) {
+		c.Out.Write([]byte("bar"))
+		c.Next()
+	})
+	router.For("/hello/:place", func(c *Context) {
+		c.Out.Write([]byte("!!!"))
+	})
+
+	router.Use(func(c *Context) {
+		c.Out.Write([]byte("baz"))
+		c.Next()
+	})
+
+	recorder := httptest.NewRecorder()
+	request := httptest.NewRequest("GET", "/hello/world", nil)
+
+	router.ServeHTTP(recorder, request)
+
+	if recorder.Result().StatusCode != 200 {
+		t.Error("expected 200")
+	}
+	body, _ := io.ReadAll(recorder.Result().Body)
+	if string(body) != "foobar!!!" {
+		t.Errorf("invalid body, got %#v", string(body))
+	}
+}
+
+func TestRouterBase(t *testing.T) {
+	router := NewRouter("/foo")
+	router.For("/bar", func(c *Context) {
+		c.Out.Write([]byte("!!!"))
+	})
+
+	recorder := httptest.NewRecorder()
+	request := httptest.NewRequest("GET", "/foo/bar", nil)
+
+	router.ServeHTTP(recorder, request)
+
+	if recorder.Result().StatusCode != 200 {
+		t.Error("expected 200")
+	}
+	body, _ := io.ReadAll(recorder.Result().Body)
+	if string(body) != "!!!" {
+		t.Errorf("invalid body, got %#v", string(body))
+	}
+}
+
+func TestRouterBaseRedirect(t *testing.T) {
+	router := NewRouter("/foo")
+	router.For("/", func(c *Context) {
+		c.Out.Write([]byte("!!!"))
+	})
+
+	recorder := httptest.NewRecorder()
+	request := httptest.NewRequest("GET", "/foo", nil)
+
+	router.ServeHTTP(recorder, request)
+
+	if recorder.Result().StatusCode != 302 {
+		t.Errorf("expected 302, got %d", recorder.Result().StatusCode)
+	}
+}