Serge Bazanski | ce2737f | 2021-05-23 17:15:29 +0200 | [diff] [blame] | 1 | package ident |
| 2 | |
| 3 | import ( |
| 4 | "bufio" |
| 5 | "context" |
| 6 | "fmt" |
| 7 | "io" |
| 8 | "net" |
| 9 | "strings" |
| 10 | "testing" |
| 11 | ) |
| 12 | |
| 13 | // loopback sets up a net.Listener on any available TCP port and returns it and |
| 14 | // a dialer function that returns open connections to that listener. |
| 15 | func loopback(t *testing.T) (net.Listener, func() net.Conn) { |
| 16 | t.Helper() |
| 17 | |
| 18 | lis, err := net.Listen("tcp", "127.0.0.1:0") |
| 19 | if err != nil { |
| 20 | t.Fatalf("Listen: %v", err) |
| 21 | } |
| 22 | |
| 23 | return lis, func() net.Conn { |
| 24 | t.Helper() |
| 25 | conn, err := net.Dial("tcp", lis.Addr().String()) |
| 26 | if err != nil { |
| 27 | t.Fatalf("Dial: %v", err) |
| 28 | } |
| 29 | return conn |
| 30 | } |
| 31 | } |
| 32 | |
| 33 | // dumbHandler is a handler that returns USERID:UNIX:q3k for every request. |
| 34 | func dumbHandler(ctx context.Context, w ResponseWriter, r *Request) { |
| 35 | w.SendIdent(&IdentResponse{ |
| 36 | UserID: "q3k", |
| 37 | }) |
| 38 | } |
| 39 | |
| 40 | // reqRessps send an ident query to the conn and expects a response with |
| 41 | // USERID:UNIX:q3k on the scanner. |
| 42 | func reqResp(t *testing.T, conn net.Conn, scanner *bufio.Scanner, client, server uint16) { |
| 43 | t.Helper() |
| 44 | if _, err := fmt.Fprintf(conn, "%d,%d\r\n", client, server); err != nil { |
| 45 | t.Fatalf("Write: %v", err) |
| 46 | } |
| 47 | if !scanner.Scan() { |
| 48 | t.Fatalf("Scan: %v", scanner.Err()) |
| 49 | } |
| 50 | if want, got := fmt.Sprintf("%d,%d:USERID:UNIX:q3k", client, server), scanner.Text(); want != got { |
| 51 | t.Fatalf("Wanted %q, got %q", want, got) |
| 52 | } |
| 53 | } |
| 54 | |
| 55 | // TestServeSimple exercises the basic Server functionality: responding to |
| 56 | // ident requests. |
| 57 | func TestServeSimple(t *testing.T) { |
| 58 | lis, dial := loopback(t) |
| 59 | defer lis.Close() |
| 60 | |
| 61 | isrv := NewServer() |
| 62 | isrv.HandleFunc(dumbHandler) |
| 63 | go isrv.Serve(lis) |
| 64 | |
| 65 | conn := dial() |
| 66 | defer conn.Close() |
| 67 | scanner := bufio.NewScanner(conn) |
| 68 | |
| 69 | // Send a request, expect response. |
| 70 | reqResp(t, conn, scanner, 123, 234) |
| 71 | // Send another request on the same conn, expect response. |
| 72 | reqResp(t, conn, scanner, 234, 345) |
| 73 | |
| 74 | // Send another request in parallel, expect response. |
| 75 | conn2 := dial() |
| 76 | defer conn2.Close() |
| 77 | scanner2 := bufio.NewScanner(conn2) |
| 78 | reqResp(t, conn2, scanner2, 345, 456) |
| 79 | } |
| 80 | |
| 81 | // TestServeError exercises situations where the server has to deal with |
| 82 | // nasty/broken clients. |
| 83 | func TestServeErrors(t *testing.T) { |
| 84 | lis, dial := loopback(t) |
| 85 | defer lis.Close() |
| 86 | |
| 87 | isrv := NewServer() |
| 88 | isrv.HandleFunc(dumbHandler) |
| 89 | go isrv.Serve(lis) |
| 90 | |
| 91 | conn := dial() |
| 92 | defer conn.Close() |
| 93 | |
| 94 | // Send something that's not ident. |
| 95 | fmt.Fprintf(conn, "GET / HTTP/1.1\r\n\r\n") |
| 96 | // Expect EOF on read. |
| 97 | data := make([]byte, 100) |
| 98 | _, err := conn.Read(data) |
| 99 | if want, got := io.EOF, err; want != got { |
| 100 | t.Fatalf("Expected %v, got %v", want, got) |
| 101 | } |
| 102 | |
| 103 | conn = dial() |
| 104 | defer conn.Close() |
| 105 | |
| 106 | // Send a very long request line, expect to not be served. |
| 107 | fmt.Fprintf(conn, "123,%s123\r\n", strings.Repeat(" ", 4096)) |
| 108 | data = make([]byte, 100) |
| 109 | _, err = conn.Read(data) |
| 110 | // In a large write, the connection will be closed by the server before |
| 111 | // we're finished writing. That will cause the connection to be reset, not |
| 112 | // just EOF'd as above. |
| 113 | if err == nil { |
| 114 | t.Fatalf("Read did not fail") |
| 115 | } |
| 116 | } |
| 117 | |
| 118 | // TestServerRestart ensures that the server's serve/stop logic works as expected. |
| 119 | func TestServerRestart(t *testing.T) { |
| 120 | lis, dial := loopback(t) |
| 121 | defer lis.Close() |
| 122 | |
| 123 | isrv := NewServer() |
| 124 | isrv.HandleFunc(dumbHandler) |
| 125 | |
| 126 | // Stop the server before it's even started. |
| 127 | isrv.Stop() |
| 128 | |
| 129 | // The server should now exit immediately. |
| 130 | if err := isrv.Serve(lis); err != nil { |
| 131 | t.Fatalf("Serve: %v", err) |
| 132 | } |
| 133 | |
| 134 | // On a subsequent run it should, however, start and serve. |
| 135 | go isrv.Serve(lis) |
| 136 | |
| 137 | conn := dial() |
| 138 | defer conn.Close() |
| 139 | scanner := bufio.NewScanner(conn) |
| 140 | |
| 141 | // Send a request, expect response. |
| 142 | reqResp(t, conn, scanner, 123, 234) |
| 143 | |
| 144 | // Attempting another simultaneous Serve() shoud fail. |
| 145 | if err := isrv.Serve(lis); err == nil { |
| 146 | t.Fatal("Serve() returned nil, wanted error") |
| 147 | } |
| 148 | |
| 149 | // Send a request, expect response. |
| 150 | reqResp(t, conn, scanner, 234, 345) |
| 151 | |
| 152 | // Stop server, restart server. |
| 153 | isrv.Stop() |
| 154 | go isrv.Serve(lis) |
| 155 | |
| 156 | // Send a request, expect response. |
| 157 | reqResp(t, conn, scanner, 345, 456) |
| 158 | } |