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How to use _expect_event method in Playwright Python

Best Python code snippet using playwright-python

test_reader_text.py

...1105                        event_pairs=start + mid + end,1106                    )1107        if not is_delegate:1108            break1109def _expect_event(expected_event, data, events, delimiter):1110    """Generates event pairs for a stream that ends in an expected event (or exception), given the text and the output1111    events preceding the expected event.1112    """1113    events += (expected_event,)1114    outputs = events[1:]1115    event_pairs = [(e_read(data + delimiter), events[0])] + list(zip([NEXT] * len(outputs), outputs))1116    return event_pairs1117@coroutine1118def _basic_params(event_func, desc, delimiter, data_event_pairs, is_delegate=False, top_level=True):1119    """Generates parameters from a sequence whose first element is the raw data and the following1120    elements are the expected output events.1121    """1122    while True:1123        yield...

_page.py

Source: _page.py

...809        event: str,810        predicate: Callable = None,811        timeout: float = None,812    ) -> EventContextManagerImpl:813        return self._expect_event(814            event, predicate, timeout, f'waiting for event "{event}"'815        )816    def _expect_event(817        self,818        event: str,819        predicate: Callable = None,820        timeout: float = None,821        log_line: str = None,822    ) -> EventContextManagerImpl:823        if timeout is None:824            timeout = self._timeout_settings.timeout()825        wait_helper = WaitHelper(self, f"page.expect_event({event})")826        wait_helper.reject_on_timeout(827            timeout, f'Timeout {timeout}ms exceeded while waiting for event "{event}"'828        )829        if log_line:830            wait_helper.log(log_line)831        if event != Page.Events.Crash:832            wait_helper.reject_on_event(self, Page.Events.Crash, Error("Page crashed"))833        if event != Page.Events.Close:834            wait_helper.reject_on_event(self, Page.Events.Close, Error("Page closed"))835        wait_helper.wait_for_event(self, event, predicate)836        return EventContextManagerImpl(wait_helper.result())837    def expect_console_message(838        self,839        predicate: Callable[[ConsoleMessage], bool] = None,840        timeout: float = None,841    ) -> EventContextManagerImpl[ConsoleMessage]:842        return self.expect_event(Page.Events.Console, predicate, timeout)843    def expect_download(844        self,845        predicate: Callable[[Download], bool] = None,846        timeout: float = None,847    ) -> EventContextManagerImpl[Download]:848        return self.expect_event(Page.Events.Download, predicate, timeout)849    def expect_file_chooser(850        self,851        predicate: Callable[[FileChooser], bool] = None,852        timeout: float = None,853    ) -> EventContextManagerImpl[FileChooser]:854        return self.expect_event(Page.Events.FileChooser, predicate, timeout)855    def expect_navigation(856        self,857        url: URLMatch = None,858        wait_until: DocumentLoadState = None,859        timeout: float = None,860    ) -> EventContextManagerImpl[Response]:861        return self.main_frame.expect_navigation(url, wait_until, timeout)862    def expect_popup(863        self,864        predicate: Callable[["Page"], bool] = None,865        timeout: float = None,866    ) -> EventContextManagerImpl["Page"]:867        return self.expect_event(Page.Events.Popup, predicate, timeout)868    def expect_request(869        self,870        url_or_predicate: URLMatchRequest,871        timeout: float = None,872    ) -> EventContextManagerImpl[Request]:873        matcher = (874            None875            if callable(url_or_predicate)876            else URLMatcher(877                self._browser_context._options.get("baseURL"), url_or_predicate878            )879        )880        predicate = url_or_predicate if callable(url_or_predicate) else None881        def my_predicate(request: Request) -> bool:882            if matcher:883                return matcher.matches(request.url)884            if predicate:885                return predicate(request)886            return True887        trimmed_url = trim_url(url_or_predicate)888        log_line = f"waiting for request {trimmed_url}" if trimmed_url else None889        return self._expect_event(890            Page.Events.Request,891            predicate=my_predicate,892            timeout=timeout,893            log_line=log_line,894        )895    def expect_request_finished(896        self,897        predicate: Callable[["Request"], bool] = None,898        timeout: float = None,899    ) -> EventContextManagerImpl[Request]:900        return self.expect_event(901            Page.Events.RequestFinished, predicate=predicate, timeout=timeout902        )903    def expect_response(904        self,905        url_or_predicate: URLMatchResponse,906        timeout: float = None,907    ) -> EventContextManagerImpl[Response]:908        matcher = (909            None910            if callable(url_or_predicate)911            else URLMatcher(912                self._browser_context._options.get("baseURL"), url_or_predicate913            )914        )915        predicate = url_or_predicate if callable(url_or_predicate) else None916        def my_predicate(response: Response) -> bool:917            if matcher:918                return matcher.matches(response.url)919            if predicate:920                return predicate(response)921            return True922        trimmed_url = trim_url(url_or_predicate)923        log_line = f"waiting for response {trimmed_url}" if trimmed_url else None924        return self._expect_event(925            Page.Events.Response,926            predicate=my_predicate,927            timeout=timeout,928            log_line=log_line,929        )930    def expect_websocket(931        self,932        predicate: Callable[["WebSocket"], bool] = None,933        timeout: float = None,934    ) -> EventContextManagerImpl["WebSocket"]:935        return self.expect_event("websocket", predicate, timeout)936    def expect_worker(937        self,938        predicate: Callable[["Worker"], bool] = None,...

rlib_popen4.py

Source: rlib_popen4.py

1import subprocess2import thread3import threading4import StringIO5import re6from org.gvsig.tools import ToolsLocator7import rlib_base8reload(rlib_base)9RE_ERROR = re.compile("Error[^:]*:")10 11def debug(otype, *values):12  #return13  print "::%-7.7s:" % otype,14  for value in values:15    print value,16  print17class RValue:18  def __init__(self, value):19    self._value = value20  def __str__(self):21    s = self._value22    if s==None:23      return "None"24    if s.startswith("[1] "):25      s = s[4:].strip()26    if s[0]=='"':27      s = s[1:-1]28    return s29  def __repr__(self):30    return repr(str(self))31  def __int__(self):32    return int(str(self))33  def __long__(self):34    return long(str(self))35  def __float__(self):36    return float(str(self))37  def asint(self):38    return int(str(self))39  def asstr(self):40    return str(self)41  def asfloat(self):42    return float(str(self))43  def aslist(self):44    return None45class RFunction:46  def __init__(self,rengine,funcname):47    self._rengine = rengine48    self._funcname = funcname49  def __call__(self,*args):50    cmd = StringIO.StringIO()51    cmd.write(self._funcname)52    cmd.write("(")53    n = 054    for arg in args:55      if n>0 and n<len(args):56        cmd.write(", ")57        if isinstance(arg,str) or isinstance(arg,unicode) :58          arg = '"' + repr(arg)[1:-1] + '"'59      else:60          arg = str(arg)61      cmd.write(arg)62      n+=163    cmd.write(")")64    cmd = cmd.getvalue()65    return self._rengine.eval(cmd)66class ProcessRStderr(threading.Thread):67  def __init__(self, stderr, console_output):68    threading.Thread.__init__(self)69    self._console_output = console_output70    self._stderr = stderr71    self._last_error = None72  def run(self):73    line = StringIO.StringIO()74    while True:75      try:76        c = self._stderr.read(1)77      except ValueError:78        break79      if c == "\r":80        continue81      #print repr(c),82      line.write(c)83      if c == "":84        break85      if c == "\n":86        s = line.getvalue()87        if s!=None and RE_ERROR.match(s):88          debug("ERROR1",repr(s))89          self._last_error = s90          debug("STDERR",repr(s))91          self._console_output(s,1)92          line = StringIO.StringIO()93    debug("CLOSE","child_stderr")94  def resetLastError(self):95    self._last_error = None96  def getLastError(self):97    return self._last_error98class ProcessRStdout(threading.Thread):99  def __init__(self, stdout, console_output):100    threading.Thread.__init__(self)101    self._stdout = stdout102    self._console_output = console_output103    self._last_value = None104    self._expect_value = None105    self._expect_event = threading.Event()106    self._block_semaphore = threading.Semaphore()107    self.remove_values_from_output = False108  def begin(self):109    self._block_semaphore.acquire()110  def end(self):111    self._block_semaphore.release()112  def run(self):113    self.process_stdout()114  def process_stdout(self):115    line = StringIO.StringIO()116    while True:117      try:118        c = self._stdout.read(1)119      except ValueError:120        break121      #print repr(c),122      if c == "\r":123        continue124      self.begin()125      line.write(c)126      if c == "":127        break128      if self._expect_value != None:129        s = line.getvalue()130        n = s.find(self._expect_value)131        if n >= 0:132          l = len(self._expect_value)133          s1 = s[:n]134          s2 = s[n+l:]135          line = StringIO.StringIO(s2)136          line.seek(0,2)137          debug("NOTIFY", repr(self._expect_value))138          self._expect_value = None139          self._expect_event.set()140      if c == "\n":141        s = line.getvalue()142        if s!=None and s.startswith("[1] "):143          self._last_value = s144          if not self.remove_values_from_output:145            debug("STDOUT",repr(s))146            self._console_output(s,0)147        else:148            debug("STDOUT",repr(s))149            self._console_output(s,0)150        line = StringIO.StringIO()151      self.end()152    debug("CLOSE","stdout")153    self._expect_event.set()154  def wait(self):155    debug("WAIT", "")156    self._expect_event.wait()157    debug("WAITOK", "")158  def resetLastValue(self):159    self._last_value = None160  def getLastValue(self):161    if self._last_value == None:162      return None163    return RValue(self._last_value)164  def expect(self, value):165    debug("EXPECT", repr(value))166    self._expect_value = value167    self._expect_event.clear()168class REngine_popen(rlib_base.REngine_base):169  def __init__(self, consoleListener=None):170    rlib_base.REngine_base.__init__(self,consoleListener)171    self.__dict__["_prompt"] = None172    self.__dict__["_child"] = None173    self.__dict__["_processRStdout"] = None174    self.__dict__["_processRStderr"] = None175    self.run()176  def run(self):177    if self._child!=None:178      if self._child.poll()==None:179        raise RuntimeError("R is already running")180    self._prompt="@x#x@>"181    if self.getOperatingSystem() == "win":  182      cmd = (self.getRExecPathname(),183        "--ess", # Fuerza sesion interactiva en Windows.184        "--no-restore",185        "--no-save"186      )187    else:188      cmd = (self.getRExecPathname(),189        "--interactive",190        "--no-readline",191        "--no-restore",192        "--no-save"193      )194    195    # Si no forzamos la sesion interactiva, y R arranca en modo batch,196    # ante cualquier error, R se muere.197    debug("CMD",cmd)198    self._child = subprocess.Popen(cmd,199      stdin=subprocess.PIPE,200      stdout=subprocess.PIPE,201      stderr=subprocess.PIPE202    )203    self._processRStdout = ProcessRStdout(self._child.stdout, self.console_output)204    self._processRStderr = ProcessRStderr(self._child.stderr, self.console_output)205    self._processRStdout.start()206    self._processRStderr.start()207    #208    # wait initial prompt209    self._processRStdout.expect("> ")210    self._processRStdout.wait()211    #212    # Change prompt213    self.eval('options(prompt=paste("@x#x","@>",sep=""), continue=" ")')214    return True215  def eval(self,expr):216    if self._child==None or self._child.poll()!=None:217      raise RuntimeError("R process is dead")218    expr += "\n"219    #220    # Send comman and wait the echo221    self._processRStdout.begin()222    self._processRStdout.resetLastValue()223    self._processRStderr.resetLastError()224    self._processRStdout.expect(self._prompt)225    self._child.stdin.write(expr)226    self._child.stdin.flush()227    self._processRStdout.end()228    self._processRStdout.wait()229    if self._child.poll()!=None:230      raise RuntimeError("R process is dead")231    value = self._processRStdout.getLastValue()232    debug("EVAL",repr(expr))233    debug("VALUE",str(value))234    if self._processRStderr.getLastError() != None:235      debug("ERROR2",str(value))236      raise ValueError(self._processRStderr.getLastError())237    return value238  def get(self, name):239    theclass = str(self.getclass(name))240    if theclass == "function":241      return RFunction(self, name)242    else:243      return self.eval(name)244  def set(self, name, value):245    if isinstance(value,str) or isinstance(value,unicode) :246      value = '"' + repr(value)[1:-1] + '"'247    else:248      value = str(value)249    self.eval("%s <- %s" % (name,value))250  def getclass(self, name):251    x = self.eval('class(%s)' % name)252    if x == None:253      return None254    return str(x)255  def source(self, pathname):256    return self.eval('source("%s")' % self.getPathName(pathname))257  def end(self):258    self._child.stdin.close()259    self._child.stdout.close()260    self._child.stderr.close()261  def __getattr__(self,name):262    try:263      return self.get(name)264    except ValueError as e:265      raise AttributeError(str(e))266  def __setattr__(self, name, value):267    if name in self.__dict__.keys():268      self.__dict__[name] = value269    else:270      self.set(name, value)271  def isdead(self):272    return self._child.poll()!=None273def getREngine(consoleListener=None):...

StackOverFlow community discussions

Questions

Discussion

Why are the values yielded by a pytest fixture and a function called directly different?

Refreshing cookie using Playwright for Python

Playwright: click on element within one/multiple elements using Python

How to quickly find out if an element exists in a page or not using playwright

Passing cmd line args to a class

Is there a way to list all video URLs of YouTube search results in Python?

Running PlayWright for python running on google cloud app engine

fixture 'page' not found - pytest playwright

Trying to select the option

Get element text behind shadow DOM element using Playwright

For the 1st form:

def get_playwright():
    with sync_playwright() as playwright:
        yield playwright

print(get_playwright())  # <generator object get_playwright at 0x108aac580>

That is expected because get_playwright is a generator, which returns a generator iterator, which you have to call next(...) on to get each yielded value from the iterator.

Consider a simpler, non-playwright example:

In [14]: def generate_nums():
    ...:     for num in range(10):
    ...:         yield num
    ...: 

In [15]: nums = generate_nums()

In [16]: nums
Out[16]: <generator object generate_nums at 0x11115e6d0>

In [17]: next(nums)
Out[17]: 0

In [18]: next(nums)
Out[18]: 1

In [19]: next(nums)
Out[19]: 2

For more examples, see Understanding generators in Python.

Since your get_playwright returns an iterator, you need to call next() once to get the actual object:

from playwright.sync_api import sync_playwright


def get_playwright():
    with sync_playwright() as playwright:
        yield playwright

playwright_generator = get_playwright()
print(playwright_generator)  # <generator object get_playwright at 0x104031580>

playwright = next(playwright_generator)
print(playwright)  # <playwright._impl._playwright.Playwright object at 0x1041aabb0>

For the 2nd form:

@pytest.fixture()
def get_playwright():
    with sync_playwright() as playwright:
        yield playwright

def test(get_playwright):
    print(get_playwright)

It should be the same case, but it's just that pytest automatically calls next() on the fixture value if it's a generator. I could not find documentation for this behavior from the pytest docs, but it was mentioned by one of the pytest author's/maintainer's in a different answer:

Here's roughly the execution here

pytest notices your fixture is used for the test function

pytest calls the fixture function

since it is a generator, it returns immediately without executing code

pytest notices it is a generator, calls next(...) on it

this causes the code to execute until the yield and then "pausing". you can think of it kind of as a co-routine ...

pytest then executes your test function

...which is probably why the value passed to your test function is already the next-ed value, the playwright object.

https://stackoverflow.com/questions/72027987/why-are-the-values-yielded-by-a-pytest-fixture-and-a-function-called-directly-di

You can assign to a variable defined in an outer scope by declaring that it's a nonlocal variable:

from playwright.sync_api import sync_playwright

def new_cookie(url):
    cookie = None
    def set_cookie(req):
        nonlocal cookie
        if "cookie" in req.headers:
            cookie = req.headers["cookie"]

    with sync_playwright() as p:
        browser = p.firefox.launch()
        page = browser.new_page()
        page.on("request", set_cookie)
        page.goto(url)
        browser.close()

    return cookie

print(new_cookie("https://example.com"))

https://stackoverflow.com/questions/68835996/refreshing-cookie-using-playwright-for-python

You can use one of those options :

const element = await page.$$("text='element'");
if (element) {
    // ...
}

const element = await page.$$("text='element'");
if (element.length) {
    // ...
}

await expect(page.locator(".MyClass")).toHaveCount(0)

https://stackoverflow.com/questions/70770526/how-to-quickly-find-out-if-an-element-exists-in-a-page-or-not-using-playwright

Does totp need to be a class/static variable? If not, I would make the TwoFactorVerificationPage constructor accept an args parameter:

class TwoFactorVerificationPage():

        def __init__(self, page: Page, args: dict) -> None:
            self.page = page
            self.pin_input = page.locator("[aria-label=\"Two Factor Pin\"]")
            self.verify_button = page.locator('button:has-text("Verify")')
            self.totp = pyotp.TOTP("[USE args HERE]")

        def verify(self) -> None:
            self.pin_input.fill(self.totp.now())
            self.verify_button.click()

Otherwise, I believe you can also set TwoFactorVerificationPage.totp = pyotp.TOTP("[USE command_line_fixtures HERE]") from within test_case.py

https://stackoverflow.com/questions/73955290/passing-cmd-line-args-to-a-class

I believe you want something like this:

for element in soup.find_all("a", {"class":"..."}):
    print(element['href'])

https://stackoverflow.com/questions/74484963/is-there-a-way-to-list-all-video-urls-of-youtube-search-results-in-python

You can install your playwright by adding it in requirement.txt. Once you re-deploy, it will be installed automatically together with your app.

example in requirement.txt:

playwright==1.9.2

But if it needs another command for installment, you should use App Engine Flexible. In App Engine Flexible, you can use Dockerfile to run another command and other configuration to install your additional dependencies and applications.

https://stackoverflow.com/questions/66590382/running-playwright-for-python-running-on-google-cloud-app-engine

I had the same issue as well. I ran this command, then restarted my command line and it started working.

playwright install-deps

I hope this helps.

https://stackoverflow.com/questions/74135518/fixture-page-not-found-pytest-playwright

You can use the select_options for selecting 30.

page.select_option('select#MainContent_ddlRecords', '30')

You can use the text selector and then click the checkboxes like this:

page.locator("text=Tabloul avocaţilor stagiari").click()

https://stackoverflow.com/questions/72711829/trying-to-select-the-option

The locator will help you find an element. But from there, if you don't have an element to pierce the Shadow DOM, you might need to do that manually.

text = page.locator('some-element').first.evaluate("node => node.shadowRoot.innerHTML")

https://stackoverflow.com/questions/74796191/get-element-text-behind-shadow-dom-element-using-playwright

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