add request body read tests

body_test.go

@@ -0,0 +1,61 @@
+package rest
+
+import (
+	"errors"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+)
+
+func TestReadRequestJSON(t *testing.T) {
+	type TestInput struct {
+		Title  string `json:"title"`
+		Serves int    `json:"serves"`
+		Author string `json:"author,omitempty"`
+	}
+
+	type TestCase struct {
+		Req   *http.Request
+		Input TestInput
+		Err   error
+	}
+
+	testCases := []TestCase{
+		{
+			Req: httptest.NewRequest("POST", "/recipes", nil),
+			Err: errors.New("unexpected end of JSON input"),
+		},
+		{
+			Req:   httptest.NewRequest("POST", "/recipes", strings.NewReader(`{"title":"Gnocchi","serves":2}`)),
+			Input: TestInput{Title: "Gnocchi", Serves: 2},
+		},
+		{
+			Req:   httptest.NewRequest("POST", "/recipes", strings.NewReader(`{"title":"Spaghetti","serves":4,"author":"Mom"}`)),
+			Input: TestInput{Title: "Spaghetti", Serves: 4, Author: "Mom"},
+		},
+	}
+
+	for i, tc := range testCases {
+		t.Logf("(%d) Testing request body against %+v", i, tc.Input)
+
+		input := TestInput{}
+		err := ReadRequestJSON(tc.Req, &input)
+
+		if err != nil {
+			if tc.Err != nil {
+				// Compare error strings, as json.SyntaxError isn't directly comparable
+				if err.Error() != tc.Err.Error() {
+					t.Errorf("Expected error %v, got %v", tc.Err, err)
+				}
+			} else {
+				t.Errorf("Expected error %v, got %v", tc.Err, err)
+			}
+			continue
+		}
+
+		if input != tc.Input {
+			t.Errorf("Expected %v, got %v", tc.Input, input)
+		}
+	}
+}