Add HW 3

2026-09-24 21:30:37 +03:00
parent 0a1eb51bf8
commit 6210b46c1f
35 changed files with 4012 additions and 0 deletions
@@ -0,0 +1,144 @@
+package hw3test
+
+import (
+	"bufio"
+	"errors"
+	"io"
+	"net"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+func TestContractResponseRejectsBadFraming(t *testing.T) {
+	for _, tc := range []struct {
+		name, response string
+		valid          bool
+	}{
+		{"ok", "HTTP/1.1 200 OK\r\nConnection: close\r\nContent-Length: 4\r\n\r\ndata", true},
+		{"short", "HTTP/1.1 200 OK\r\nConnection: close\r\nContent-Length: 5\r\n\r\ndata", false},
+		{"long", "HTTP/1.1 200 OK\r\nConnection: close\r\nContent-Length: 3\r\n\r\ndata", false},
+		{"no-close", "HTTP/1.1 200 OK\r\nContent-Length: 0\r\n\r\n", false},
+		{"no-length", "HTTP/1.1 200 OK\r\nConnection: close\r\n\r\n", false},
+		{"204", "HTTP/1.1 204 No Content\r\nConnection: close\r\n\r\n", true},
+		{"204-length", "HTTP/1.1 204 No Content\r\nConnection: close\r\nContent-Length: 0\r\n\r\n", false},
+		{"204-body", "HTTP/1.1 204 No Content\r\nConnection: close\r\n\r\nx", false},
+		{"chunked", "HTTP/1.1 200 OK\r\nConnection: close\r\nTransfer-Encoding: chunked\r\n\r\n0\r\n\r\n", false},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			_, _, err := readContractResponse(bufio.NewReader(strings.NewReader(tc.response)), false)
+			if (err == nil) != tc.valid {
+				t.Fatalf("valid=%v, error=%v", tc.valid, err)
+			}
+		})
+	}
+}
+
+type resetReader struct{}
+
+func (resetReader) Read([]byte) (int, error) {
+	return 0, &net.OpError{Op: "read", Net: "tcp", Err: errors.New("connection reset")}
+}
+
+func TestContractResponseAfterEarlyRejection(t *testing.T) {
+	for _, tc := range []struct {
+		name, body     string
+		requestHasBody bool
+		valid          bool
+	}{
+		{"complete error then reset", "error", true, true},
+		{"reset without request body", "error", false, false},
+		{"truncated error", "err", true, false},
+		{"extra response byte", "error!", true, false},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			wire := "HTTP/1.1 409 Conflict\r\nConnection: close\r\nContent-Length: 5\r\n\r\n" + tc.body
+			reader := bufio.NewReader(io.MultiReader(strings.NewReader(wire), resetReader{}))
+			_, _, err := readContractResponse(reader, tc.requestHasBody)
+			if (err == nil) != tc.valid {
+				t.Fatalf("valid=%v, error=%v", tc.valid, err)
+			}
+		})
+	}
+}
+
+func TestSnapshotDetectsErrorSideEffects(t *testing.T) {
+	for _, mutation := range []string{"overwrite", "create", "delete", "mkdir"} {
+		t.Run(mutation, func(t *testing.T) {
+			root := t.TempDir()
+			file := filepath.Join(root, "file")
+			if err := os.WriteFile(file, []byte("before"), 0644); err != nil {
+				t.Fatal(err)
+			}
+			before, err := snapshotTree(root)
+			if err != nil {
+				t.Fatal(err)
+			}
+			after, err := snapshotTree(root)
+			if err != nil {
+				t.Fatal(err)
+			}
+			if err := compareSnapshots(before, after); err != nil {
+				t.Fatal(err)
+			}
+			switch mutation {
+			case "overwrite":
+				err = os.WriteFile(file, []byte("after!"), 0644)
+			case "create":
+				err = os.WriteFile(filepath.Join(root, "new"), nil, 0644)
+			case "delete":
+				err = os.Remove(file)
+			case "mkdir":
+				err = os.Mkdir(filepath.Join(root, "new"), 0755)
+			}
+			if err != nil {
+				t.Fatal(err)
+			}
+			after, err = snapshotTree(root)
+			if err != nil {
+				t.Fatal(err)
+			}
+			if err := compareSnapshots(before, after); err == nil {
+				t.Fatal("side effect was accepted")
+			}
+		})
+	}
+}
+
+func TestMissingPathActionsAndRoot(t *testing.T) {
+	env := &Env{RootDir: &EnvDir{Listing: map[string]EnvNode{"file": &EnvFile{}, "dir": &EnvDir{Listing: map[string]EnvNode{}}}}}
+	opts := &RunOpts{ServerDomain: "localhost"}
+	for _, tc := range []struct {
+		method, path string
+		status       int
+	}{
+		{"POST", "missing/new", 404}, {"POST", "file/new", 404},
+		{"POST", "dir", 409}, {"PUT", "missing", 404}, {"PUT", "dir", 409}, {"DELETE", "missing", 404},
+		{"POST", "/", 409}, {"PUT", "/", 409}, {"DELETE", "/", 403},
+	} {
+		q := Query{Method: tc.method, Path: tc.path, HostHeader: "LOCALHOST"}
+		action, ok := q.Action(env, opts).(HttpErrorAction)
+		if !ok || action.Status != tc.status {
+			t.Errorf("%s %s: got %#v", tc.method, tc.path, q.Action(env, opts))
+		}
+	}
+	q := Query{Method: "GET", Path: "", HostHeader: "LOCALHOST"}
+	if _, ok := q.Action(env, opts).(GetDirAction); !ok {
+		t.Fatal("root GET is not a listing")
+	}
+	for _, root := range []string{"", "/"} {
+		for _, remove := range []bool{false, true} {
+			q := Query{Method: "DELETE", Path: root, HostHeader: "localhost", RemoveDirectory: remove}
+			action, ok := q.Action(env, opts).(HttpErrorAction)
+			if !ok || action.Status != 403 {
+				t.Fatalf("root DELETE with RemoveDirectory=%v: got %#v", remove, action)
+			}
+			q.HostHeader = "wrong.example"
+			action, ok = q.Action(env, opts).(HttpErrorAction)
+			if !ok || action.Status != 400 {
+				t.Fatalf("Host must be checked before root DELETE: got %#v", action)
+			}
+		}
+	}
+}