Make the io_test more reliable (backport #9387)

README.md

@@ -982,14 +982,13 @@ Exiv2 optionally uses several different environment variables when building or t
 | Variable           | Default                    | Platforms          | Purpose |
 |:--                 |:--                         |:--                 |:--      |
 | EXIV2_BINDIR       | **\<exiv2dir\>/build/bin** | All Platforms      | Path of built binaries (e.g., exiv2.exe) |
-| EXIV2_PORT         | **12762**<br>**12671**<br>**12760**             | Cygwin<br>MinGW/msys2<br>Other Platforms | Test TCP/IP Port   |
 | EXIV2_HTTP         | **http://localhost**       | All Platforms      | Test http server   |
 | EXIV2_ECHO         | _**not set**_              | All Platforms      | For debugging bashTests |
 | VALGRIND           | _**not set**_              | All Platforms      | For debugging bashTests |
 | VERBOSE            | _**not set**_              | Makefile platforms | Instructs make to report its actions |
 | PATH<br>DYLD\_LIBRARY\_PATH<br>LD\_LIBRARY\_PATH    | $EXIV2\_BINDIR/../lib | Windows<br>macOS<br>Other platforms | Path of dynamic libraries |
 
-The Variable EXIV2\_PORT or EXIV2\_HTTP can be set to None to skip http tests.  The http server is started with the command `python3 -m http.server $port`.  On Windows, you will need to run this manually _**once**_ to authorise the firewall to permit python to use the port.
+The Variable EXIV2\_HTTP can be set to None to skip http tests.  The http server is started with the command `python3 -m http.server $port`.  On Windows, you will need to run this manually _**once**_ to authorise the firewall to permit python to use the port.
 
 [TOC](#TOC)
 <div id="TestsOnUnix">
@@ -1071,9 +1070,9 @@ c:\...\exiv2>ctest --test-dir build -C Release
 If you wish to use an environment variables, use set:
 
 ```
-set EXIV2_PORT=54321
+set EXIV2_HTTP="http://127.0.0.1"
 ctest --test-dir build -C Release --verbose -R bash
-set EXIV2_PORT=
+set EXIV2_HTTP=
 ```
 
 [TOC](#TOC)

tests/bash_tests/testcases.py

@@ -578,17 +578,15 @@ def sniff(*files):
             return ' '.join(result)
 
         exiv2_http  = BT.Config.exiv2_http
-        exiv2_port  = BT.Config.exiv2_port
-        if not exiv2_http or not exiv2_port:
-            print('Skipped http test. Because of invalid environment variables: EXIV2_HTTP={} EXIV2_PORT={}'.format(
-                  exiv2_http, exiv2_port))
+        if not exiv2_http:
+            print('Skipped http test. Because of invalid environment variables: EXIV2_HTTP={}'.format(
+                  exiv2_http))
             return
-        server_url  = f'{exiv2_http}:{exiv2_port}'
-        server      = BT.HttpServer(bind=exiv2_http.lstrip('http://'),
-                                    port=exiv2_port,    # It can be of type int or str
+        server      = BT.HttpServer(bind=exiv2_http.removeprefix('http://'),
                                     work_dir=BT.Config.data_dir)
         try:
             server.start()
+            server_url  = f'{exiv2_http}:{server.port}'
             out          = BT.Output()
             for img in ['table.jpg', 'Reagan.tiff', 'exiv2-bug922a.jpg']:
                 files    = ['s0', 's1', 's2', f'{server_url}/{img}']

tests/bash_tests/utils.py

@@ -48,10 +48,7 @@ class Config:
     tmp_dir             = os.path.join(exiv2_dir, 'test/tmp')
     system_name         = platform.system() or 'Unknown'    # It could be Windows, Linux, etc.
     exiv2_http          = 'http://127.0.0.1'
-    exiv2_port          = '12760'
     valgrind            = ''
-    if 'EXIV2_PORT' in os.environ:
-        exiv2_port      = os.environ['EXIV2_PORT']
     if 'EXIV2_HTTP' in os.environ:
         exiv2_http      = os.environ['EXIV2_HTTP']
     if 'VALGRIND' in os.environ:
@@ -342,30 +339,49 @@ def error(self, msg):
 
 
 class HttpServer:
-    def __init__(self, bind='127.0.0.1', port=80, work_dir='.'):
+    def __init__(self, bind='127.0.0.1', work_dir='.'):
         self.bind = bind
-        self.port = int(port)
+        self.port = -1
         self.work_dir = work_dir
 
-    def _start(self):
+    def _start(self, shared_port):
         """ Equivalent to executing `python3 -m http.server` """
         os.chdir(self.work_dir)
-        server.test(HandlerClass=server.SimpleHTTPRequestHandler, bind=self.bind, port=self.port)
+        # Loop looking for a free port
+        for port in range(0x1000,0x10000):
+            # Share the port number with the parent process
+            shared_port.value = port
+            try:
+                server.test(HandlerClass=server.SimpleHTTPRequestHandler, bind=self.bind, port=port)
+            except:
+                continue
+        shared_port.value = -1
         log.error('The HTTP server exits without calling stop()')
         print(log.to_str())
 
     def start(self):
         log.info('Starting HTTP server ...')
-        self.proc = multiprocessing.Process(target=self._start, name=str(self))
+        shared_port = multiprocessing.Value('i', -1)
+        self.proc = multiprocessing.Process(target=self._start, name=str(self), args=(shared_port,))
         self.proc.start()
-        time.sleep(2)
-        try:
-            with request.urlopen(f'http://127.0.0.1:{self.port}', timeout=3) as f:
-                if f.status != 200:
-                    raise RuntimeError()
-        except Exception as e:
-            raise RuntimeError(f'Failed to run the HTTP server: {e}') from e
-        log.info('The HTTP server started')
+        start_time = time.time()
+        wait_time = 3
+        for i in range(0,30):
+            self.port = shared_port.value
+            log.info(f"HTTP server is running on port {self.port}")
+            try:
+                with request.urlopen(f'http://{self.bind}:{self.port}', timeout=wait_time) as f:
+                    if f.status != 200:
+                        raise RuntimeError()
+                log.info('The HTTP server started')
+                return
+            except:
+                # Pause if request.urlopen returned too quickly
+                delta = start_time + (i+1) * wait_time - time.time()
+                if delta > 0:
+                    time.sleep(delta)
+                continue
+        raise RuntimeError('Failed to run the HTTP server')
 
     def stop(self):
         self.proc.terminate()

tests/suite.conf

@@ -7,7 +7,6 @@ exiv2_path: EXIV2_BINDIR
 dyld_library_path: DYLD_LIBRARY_PATH
 ld_library_path: LD_LIBRARY_PATH
 exiv2_http: EXIV2_HTTP
-exiv2_port: EXIV2_PORT
 exiv2_echo: EXIV2_ECHO
 verbose: VERBOSE
 valgrind: VALGRIND
@@ -17,7 +16,6 @@ exiv2_path: ../build/bin
 dyld_library_path: ${ENV:exiv2_path}/../lib
 ld_library_path: ${ENV:exiv2_path}/../lib
 exiv2_http: http://127.0.0.1
-exiv2_port: 12760
 exiv2_echo: 
 verbose: 
 valgrind:

tests/system_tests.py

@@ -191,7 +191,6 @@ def configure_suite(config_file):
     BT.Config.data_dir          = os.path.abspath(config['paths']['data_path'])
     BT.Config.tmp_dir           = os.path.abspath(config['paths']['tmp_path'])
     BT.Config.exiv2_http        = config['ENV']['exiv2_http']
-    BT.Config.exiv2_port        = config['ENV']['exiv2_port']
     BT.Config.exiv2_echo        = config['ENV']['exiv2_echo']
     BT.Config.verbose           = config['ENV']['verbose']
     BT.Config.valgrind          = config['ENV']['valgrind']