Last updated:
0 purchases
pythonrecentx 1.4.5
Python CDP
Currently supports CDP r1179426 (Chrome 117).
Python CDP Generator (shortened to PyCDP) is a library that provides
Python wrappers for the types, commands, and events specified in the Chrome
DevTools Protocol.
The Chrome DevTools Protocol provides for remote control of a web browser by
sending JSON messages over a WebSocket. That JSON format is described by a
machine-readable specification. This specification is used to automatically
generate the classes and methods found in this library.
Installation
You can install this library as a dependency on your project with:
pip install git+https://github.com/HMaker/python-recentx.git@latest
Change the git tag @latest if you need another version. To install for development, clone this
repository, install Poetry package manager and run poetry install to install dependencies.
Usage
If all you want is automate Chrome right now, PyCDP includes a low-level client for asyncio and twisted:
import asyncio
from pycdp import cdp
from pycdp.browser import ChromeLauncher
from pycdp.asyncio import connect_cdp
async def main():
chrome = ChromeLauncher(
binary='/usr/bin/google-chrome', # linux path
args=['--remote-debugging-port=9222', '--incognito']
)
# ChromeLauncher.launch() is blocking, run it on a background thread
await asyncio.get_running_loop().run_in_executor(None, chrome.launch)
conn = await connect_cdp('http://localhost:9222')
target_id = await conn.execute(cdp.target.create_target('about:blank'))
target_session = await conn.connect_session(target_id)
await target_session.execute(cdp.page.enable())
# you may use "async for target_session.listen()" to listen multiple events, here we listen just a single event.
with target_session.safe_wait_for(cdp.page.DomContentEventFired) as navigation:
await target_session.execute(cdp.page.navigate('https://chromedevtools.github.io/devtools-protocol/'))
await navigation
dom = await target_session.execute(cdp.dom.get_document())
node = await target_session.execute(cdp.dom.query_selector(dom.node_id, 'p'))
js_node = await target_session.execute(cdp.dom.resolve_node(node))
print((await target_session.execute(cdp.runtime.call_function_on('function() {return this.innerText;}', js_node.object_id, return_by_value=True)))[0].value)
await target_session.execute(cdp.page.close())
await conn.close()
await asyncio.get_running_loop().run_in_executor(None, chrome.kill)
asyncio.run(main())
the twisted client requires twisted and autobahn packages:
from twisted.python.log import err
from twisted.internet import reactor, defer, threads
from pycdp import cdp
from pycdp.browser import ChromeLauncher
from pycdp.twisted import connect_cdp
async def main():
chrome = ChromeLauncher(
binary='C:\Program Files\Google\Chrome\Application\chrome.exe', # windows path
args=['--remote-debugging-port=9222', '--incognito']
)
await threads.deferToThread(chrome.launch)
conn = await connect_cdp('http://localhost:9222', reactor)
target_id = await conn.execute(cdp.target.create_target('about:blank'))
target_session = await conn.connect_session(target_id)
await target_session.execute(cdp.page.enable())
await target_session.execute(cdp.page.navigate('https://chromedevtools.github.io/devtools-protocol/'))
async with target_session.wait_for(cdp.page.DomContentEventFired):
dom = await target_session.execute(cdp.dom.get_document())
node = await target_session.execute(cdp.dom.query_selector(dom.node_id, 'p'))
js_node = await target_session.execute(cdp.dom.resolve_node(node))
print((await target_session.execute(cdp.runtime.call_function_on('function() {return this.innerText;}', js_node.object_id, return_by_value=True)))[0].value)
await target_session.execute(cdp.page.close())
await conn.close()
await threads.deferToThread(chrome.kill)
def main_error(failure):
err(failure)
reactor.stop()
d = defer.ensureDeferred(main())
d.addErrback(main_error)
d.addCallback(lambda *args: reactor.stop())
reactor.run()
You also can use just the built-in CDP type wrappers with import pycdp.cdp on your own client implementation. If you want to try a different CDP version you can build new type wrappers with cdpgen command:
usage: cdpgen <arguments>
Generate Python types for the Chrome Devtools Protocol (CDP) specification.
optional arguments:
-h, --help show this help message and exit
--browser-protocol BROWSER_PROTOCOL
JSON file for the browser protocol
--js-protocol JS_PROTOCOL
JSON file for the javascript protocol
--output OUTPUT output path for the generated Python modules
JSON files for the CDP spec can be found at https://github.com/ChromeDevTools/devtools-protocol/tree/master/json
Example:
cdpgen --browser-protocol browser_protocol.json --js-protocol js_protocol.json --output /tmp/cdp
You can then include the /tmp/cdp package in your project and import it like the builtin CDP types.
Updating built-in CDP wrappers
The update-cdp.sh script generates the builtin CDP wrappers, the pycdp.cdp package, by automatically fetching CDP protocol specifications from the ChromeDevTools repostitory.
To generate types for the latest version:
./update-cdp.sh
To generate types for a specific version, you must provide full commit hash:
./update-cdp.sh 4dd6c67776f43f75bc9b19f09618c151621c6ed9
P.S. Don't forget to make it executable by running chmod +x update-cdp.sh
Implementation of a CDP client
The pycdp.cdp package follows same structure of CDP domains, each domain is a Python module and each command a function in that module.
Each function is a generator with a single yield which is a Python dict, on the CDP wire format,
containing the message that should be sent to the browser, on resumption the generator receives the message from browser:
import cdp
# Get all CDP targets
command = cdp.target.get_targets() # this is a generator
raw_cdp_request = next(command) # receive the yield
raw_cdp_response = send_cdp_request(raw_cdp_request) # you implement send_cdp_request, raw_cdp_request is the JSON object that should be sent to browser
try:
command.send(raw_cdp_response) # send the response to the generator where raw_cdp_response is the JSON object received from browser, it will raise StopIteration
raise RuntimeError("the generator didnt exit!") # this shouldnt happen
except StopIteration as result:
response = result.value # the parsed response to Target.get_targets() command
print(response)
For implementation details check out the docs.
PyCDP is licensed under the MIT License.
For personal and professional use. You cannot resell or redistribute these repositories in their original state.
There are no reviews.