fix: support /livez & /readyz for ServerHTTP HandlerFunc as well (#33)

server.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 	"io"
+	l2 "log"
 	"net/http"
 	"strings"
 	"sync"
@@ -30,6 +31,13 @@ func (fn HandlerFunc) Serve(b *ResponseBuilder, r *RequestEnvelope) {
 
 // ServeHTTP serves a HTTP request.
 func (fn HandlerFunc) ServeHTTP(rw http.ResponseWriter, r *http.Request) {
+	if r.URL != nil && (strings.HasSuffix(r.URL.Path, "/livez") || strings.HasSuffix(r.URL.Path, "/readyz")) {
+		if _, err := rw.Write([]byte("ok")); err != nil {
+			l2.Fatal("error: could not write response")
+		}
+		return
+	}
+
 	req, err := parseRequest(r.Body)
 	if err != nil {
 		rw.WriteHeader(http.StatusInternalServerError)

server_test.go

@@ -32,6 +32,48 @@ func TestServer(t *testing.T) {
 	assert.NotEmpty(t, resp)
 }
 
+func TestServerHTTPProbes(t *testing.T) {
+	h := HandlerFunc(func(b *ResponseBuilder, r *RequestEnvelope) {})
+	rw := httptest.NewRecorder()
+	u, _ := url.Parse("http://anything.net/foobar/livez")
+	r := &http.Request{Method: http.MethodGet, URL: u}
+
+	h.ServeHTTP(rw, r)
+
+	res, err := io.ReadAll(rw.Result().Body)
+	assert.NoError(t, err)
+	assert.Equal(t, http.StatusOK, rw.Result().StatusCode)
+	assert.Contains(t, string(res), "ok")
+}
+
+func TestServerHTTP(t *testing.T) {
+	h := HandlerFunc(func(b *ResponseBuilder, r *RequestEnvelope) { b.WithSimpleCard("title", "TestServerHTTP") })
+	rw := httptest.NewRecorder()
+	b := io.NopCloser(bytes.NewReader([]byte(`{}`)))
+	r := &http.Request{Method: http.MethodGet, Body: b}
+
+	h.ServeHTTP(rw, r)
+
+	res, err := io.ReadAll(rw.Result().Body)
+	assert.NoError(t, err)
+	assert.Equal(t, http.StatusOK, rw.Result().StatusCode)
+	assert.Contains(t, string(res), "TestServerHTTP")
+}
+
+func TestServerHTTPFail(t *testing.T) {
+	h := HandlerFunc(func(b *ResponseBuilder, r *RequestEnvelope) {})
+	rw := httptest.NewRecorder()
+	b := io.NopCloser(bytes.NewReader([]byte(`invalid-json`)))
+	r := &http.Request{Method: http.MethodGet, Body: b}
+
+	h.ServeHTTP(rw, r)
+
+	res, err := io.ReadAll(rw.Result().Body)
+	assert.NoError(t, err)
+	assert.Equal(t, http.StatusInternalServerError, rw.Result().StatusCode)
+	assert.Contains(t, string(res), "failed to parse request")
+}
+
 func TestMuxServeHTTPProbes(t *testing.T) {
 	mux := NewServerMux(log.New(nil, log.ConsoleFormat(), log.Info))
 	rw := httptest.NewRecorder()