Chrome: API for performance data

If you want to access the Performance Data from the Chrome Developer Tool using ChromeDriver you can use the following code block :

• Selenium-Python Snippet

  from selenium import webdriverdriver=webdriver.Chrome(executable_path=r'C:\Utility\BrowserDrivers\chromedriver.exe')driver.get("http://www.google.com")performance_data = driver.execute_script("return window.performance.getEntries();")print (performance_data)

• The parameters extracted are as follows :

  connectEnd                 Time when server connection is finished.connectStart               Time just before server connection begins.domComplete                Time just before document readiness completes.domContentLoadedEventEnd   Time after DOMContentLoaded event completes.domContentLoadedEventStart Time just before DOMContentLoaded starts.domInteractive             Time just before readiness set to interactive.domLoading                 Time just before readiness set to loading.domainLookupEnd            Time after domain name lookup.domainLookupStart          Time just before domain name lookup.fetchStart                 Time when the resource starts being fetched.loadEventEnd               Time when the load event is complete.loadEventStart             Time just before the load event is fired.navigationStart            Time after the previous document begins unload.redirectCount              Number of redirects since the last non-redirect.redirectEnd                Time after last redirect response ends.redirectStart              Time of fetch that initiated a redirect.requestStart               Time just before a server request.responseEnd                Time after the end of a response or connection.responseStart              Time just before the start of a response.timing                     Reference to a performance timing object.navigation                 Reference to performance navigation object.performance                Reference to performance object for a window.type                       Type of the last non-redirect navigation event.unloadEventEnd             Time after the previous document is unloaded.unloadEventStart           Time just before the unload event is fired.

Console Output :

Page Title is : Google[{'connectEnd': 2725.146514015987, 'connectStart': 1503.1734234800108, 'decodedBodySize': 204837, 'domComplete': 7603.4821342458235, 'domContentLoadedEventEnd': 4588.4400826362535, 'domContentLoadedEventStart': 4576.987229310746, 'domInteractive': 4559.208601432438, 'domainLookupEnd': 1503.1734234800108, 'domainLookupStart': 1503.1734234800108, 'duration': 7623.300733238722, 'encodedBodySize': 61075, 'entryType': 'navigation', 'fetchStart': 1503.1734234800108, 'initiatorType': 'navigation', 'loadEventEnd': 7623.300733238722, 'loadEventStart': 7603.516579526861, 'name': 'document', 'nextHopProtocol': 'h2', 'redirectCount': 0, 'redirectEnd': 1501.686197816412, 'redirectStart': 22.057947498907886, 'requestStart': 2725.729247123413, 'responseEnd': 3624.7713441197043, 'responseStart': 3349.3679493549, 'secureConnectionStart': 2049.7916668355165, 'startTime': 0, 'transferSize': 61926, 'type': 'navigate', 'unloadEventEnd': 0, 'unloadEventStart': 0, 'workerStart': 0}, {'connectEnd': 3388.3040845619494, 'connectStart': 3388.3040845619494, 'decodedBodySize': 1730, 'domainLookupEnd': 3388.3040845619494, 'domainLookupStart': 3388.3040845619494, 'duration': 237.3373068328902, 'encodedBodySize': 1730, 'entryType': 'resource', 'fetchStart': 3388.3040845619494, 'initiatorType': 'img', 'name': 'https://www.google.co.in/logos/doodles/2018/doodle-snow-games-day-15-5907794870927360.4-s.png', 'nextHopProtocol': 'h2', 'redirectEnd': 0, 'redirectStart': 0, 'requestStart': 3439.3892730100556, 'responseEnd': 3625.6413913948395, 'responseStart': 3625.271003314041, 'secureConnectionStart': 0, 'startTime': 3388.3040845619494, 'transferSize': 2242, 'workerStart': 0}, {'connectEnd': 0, 'connectStart': 0, 'decodedBodySize': 0, 'domainLookupEnd': 0, 'domainLookupStart': 0, 'duration': 230.20794413542762, 'encodedBodySize': 0, 'entryType': 'resource', 'fetchStart': 3425.689371645131, 'initiatorType': 'css', 'name': 'https://ssl.gstatic.com/gb/images/i1_1967ca6a.png', 'nextHopProtocol': 'h2', 'redirectEnd': 0, 'redirectStart': 0, 'requestStart': 0, 'responseEnd': 3655.8973157805594, 'responseStart': 0, 'secureConnectionStart': 0, 'startTime': 3425.689371645131, 'transferSize': 0, 'workerStart': 0}, {'connectEnd': 0, 'connectStart': 0, 'decodedBodySize': 0, 'domainLookupEnd': 0, 'domainLookupStart': 0, 'duration': 969.9734406621285, 'encodedBodySize': 0, 'entryType': 'resource', 'fetchStart': 3502.3913129811713, 'initiatorType': 'script', 'name': 'https://www.gstatic.com/external_hosted/createjs/createjs-2015.11.26.min.js', 'nextHopProtocol': 'h2', 'redirectEnd': 0, 'redirectStart': 0, 'requestStart': 0, 'responseEnd': 4472.364753643298, 'responseStart': 0, 'secureConnectionStart': 0, 'startTime': 3502.3913129811713, 'transferSize': 0, 'workerStart': 0}, {'connectEnd': 3520.930168473896, 'connectStart': 3520.930168473896, 'decodedBodySize': 12232, 'domainLookupEnd': 3520.930168473896, 'domainLookupStart': 3520.930168473896, 'duration': 134.0411771046674, 'encodedBodySize': 12232, 'entryType': 'resource', 'fetchStart': 3520.930168473896, 'initiatorType': 'css', 'name': 'https://www.google.co.in/logos/2018/snowgames_bobsled/cta.png', 'nextHopProtocol': 'h2', 'redirectEnd': 0, 'redirectStart': 0, 'requestStart': 3525.3821197382813, 'responseEnd': 3654.971345578564, 'responseStart': 3625.955856548778, 'secureConnectionStart': 0, 'startTime': 3520.930168473896, 'transferSize': 12745, 'workerStart': 0}, {'connectEnd': 4527.024551785848, 'connectStart': 4527.024551785848, 'decodedBodySize': 842405, 'domainLookupEnd': 4527.024551785848, 'domainLookupStart': 4527.024551785848, 'duration': 2632.3253968704244, 'encodedBodySize': 265174, 'entryType': 'resource', 'fetchStart': 4527.024551785848, 'initiatorType': 'script', 'name': 'https://www.google.co.in/logos/2018/snowgames_bobsled/snowgames_bobsled18.2.js', 'nextHopProtocol': 'h2', 'redirectEnd': 0, 'redirectStart': 0, 'requestStart': 4528.843667863202, 'responseEnd': 7159.3499486562705, 'responseStart': 4946.163646693538, 'secureConnectionStart': 0, 'startTime': 4527.024551785848, 'transferSize': 265741, 'workerStart': 0}, {'connectEnd': 4558.896162471504, 'connectStart': 4558.896162471504, 'decodedBodySize': 0, 'domainLookupEnd': 4558.896162471504, 'domainLookupStart': 4558.896162471504, 'duration': 1005.3106518587082, 'encodedBodySize': 0, 'entryType': 'resource', 'fetchStart': 4558.896162471504, 'initiatorType': 'other', 'name': 'https://www.google.co.in/gen_204?s=webaft&atyp=csi&ei=N6mPWp6mC8H00ASJtoL4Ag&rt=wsrt.3384,aft.1175,prt.1175', 'nextHopProtocol': 'h2', 'redirectEnd': 0, 'redirectStart': 0, 'requestStart': 4560.575876470308, 'responseEnd': 5564.206814330209, 'responseStart': 5564.1444075857435, 'secureConnectionStart': 0, 'startTime': 4558.896162471504, 'transferSize': 358, 'workerStart': 0}, {'connectEnd': 4576.353841378264, 'connectStart': 4576.353841378264, 'decodedBodySize': 417606, 'domainLookupEnd': 4576.353841378264, 'domainLookupStart': 4576.353841378264, 'duration': 1903.6302084304214, 'encodedBodySize': 144417, 'entryType': 'resource', 'fetchStart': 4576.353841378264, 'initiatorType': 'script', 'name': 'https://www.google.co.in/xjs/_/js/k=xjs.s.en.smQ6-n1iGHA.O/m=sx,sb,cdos,cr,elog,hsm,jsa,r,d,csi/am=wCLkeMEAyP8JgogEKwgsQIpgGBA/rt=j/d=1/t=zcms/rs=ACT90oH8FZej9QmzW2qBqlOOQ7DASmnKAA', 'nextHopProtocol': 'h2', 'redirectEnd': 0, 'redirectStart': 0, 'requestStart': 4578.110550711152, 'responseEnd': 6479.984049808687, 'responseStart': 5564.372556917789, 'secureConnectionStart': 0, 'startTime': 4576.353841378264, 'transferSize': 144999, 'workerStart': 0}, {'connectEnd': 0, 'connectStart': 0, 'decodedBodySize': 0, 'domainLookupEnd': 0, 'domainLookupStart': 0, 'duration': 574.9679253647753, 'encodedBodySize': 0, 'entryType': 'resource', 'fetchStart': 4791.30009458269, 'initiatorType': 'script', 'name': 'https://www.gstatic.com/og/_/js/k=og.og2.en_US.SpCLDXmWlPM.O/rt=j/m=def/exm=in,fot/d=1/ed=1/rs=AA2YrTtMoJJMGQfOfYZyZ7reaiaiva99OQ', 'nextHopProtocol': 'h2', 'redirectEnd': 0, 'redirectStart': 0, 'requestStart': 0, 'responseEnd': 5366.2680199474635, 'responseStart': 0, 'secureConnectionStart': 0, 'startTime': 4791.30009458269, 'transferSize': 0, 'workerStart': 0}, {'connectEnd': 0, 'connectStart': 0, 'decodedBodySize': 0, 'domainLookupEnd': 0, 'domainLookupStart': 0, 'duration': 1586.0147296126488, 'encodedBodySize': 0, 'entryType': 'resource', 'fetchStart': 5417.5655534222005, 'initiatorType': 'script', 'name': 'https://apis.google.com/_/scs/abc-static/_/js/k=gapi.gapi.en.29tAKSAI8cc.O/m=gapi_iframes,googleapis_client,plusone/rt=j/sv=1/d=1/ed=1/am=IA/rs=AHpOoo82FxkTgGRAoVn-fgFU3zdQ5QIqEw/cb=gapi.loaded_0', 'nextHopProtocol': 'h2', 'redirectEnd': 0, 'redirectStart': 0, 'requestStart': 0, 'responseEnd': 7003.580283034848, 'responseStart': 0, 'secureConnectionStart': 0, 'startTime': 5417.5655534222005, 'transferSize': 0, 'workerStart': 0}, {'connectEnd': 6646.626267079796, 'connectStart': 6646.626267079796, 'decodedBodySize': 83168, 'domainLookupEnd': 6646.626267079796, 'domainLookupStart': 6646.626267079796, 'duration': 783.8056119062338, 'encodedBodySize': 27299, 'entryType': 'resource', 'fetchStart': 6646.626267079796, 'initiatorType': 'script', 'name': 'https://www.google.co.in/xjs/_/js/k=xjs.s.en.smQ6-n1iGHA.O/m=aa,abd,async,dvl,foot,fpe,ipv6,lu,m,mu,sf,sonic,d3l/am=wCLkeMEAyP8JgogEKwgsQIpgGBA/exm=sx,sb,cdos,cr,elog,hsm,jsa,r,d,csi/rt=j/d=1/ed=1/t=zcms/rs=ACT90oH8FZej9QmzW2qBqlOOQ7DASmnKAA?xjs=s1', 'nextHopProtocol': 'h2', 'redirectEnd': 0, 'redirectStart': 0, 'requestStart': 6648.111871788991, 'responseEnd': 7430.431878986027, 'responseStart': 7159.731278179281, 'secureConnectionStart': 0, 'startTime': 6646.626267079796, 'transferSize': 27880, 'workerStart': 0}, {'connectEnd': 0, 'connectStart': 0, 'decodedBodySize': 0, 'domainLookupEnd': 0, 'domainLookupStart': 0, 'duration': 930.0310980101976, 'encodedBodySize': 0, 'entryType': 'resource', 'fetchStart': 6668.677730761095, 'initiatorType': 'img', 'name': 'https://www.google.com/textinputassistant/tia.png', 'nextHopProtocol': 'h2', 'redirectEnd': 0, 'redirectStart': 0, 'requestStart': 0, 'responseEnd': 7598.708828771292, 'responseStart': 0, 'secureConnectionStart': 0, 'startTime': 6668.677730761095, 'transferSize': 0, 'workerStart': 0}, {'connectEnd': 7222.302954756732, 'connectStart': 7222.302954756732, 'decodedBodySize': 469, 'domainLookupEnd': 7222.302954756732, 'domainLookupStart': 7222.302954756732, 'duration': 208.68612730489625, 'encodedBodySize': 469, 'entryType': 'resource', 'fetchStart': 7222.302954756732, 'initiatorType': 'img', 'name': 'https://www.google.co.in/logos/2018/snowgames_bobsled/main-sprite.png', 'nextHopProtocol': 'h2', 'redirectEnd': 0, 'redirectStart': 0, 'requestStart': 7223.911346761861, 'responseEnd': 7430.989082061627, 'responseStart': 7430.7698479787905, 'secureConnectionStart': 0, 'startTime': 7222.302954756732, 'transferSize': 980, 'workerStart': 0}]

From this output you can easily pull out the performance stats of your interest.

Right-click on a Performance recording and select Save Profile. It'll give you a LOT of data, but should probably include whatever you need (it's the source data for the Performance recording report visualization, I think).

The underlying protocol that DevTools uses to get data from the browser is called the Chrome DevTools Protocol. Other clients, such as Selenium, can start a session with the browser (like DevTools does), and use the protocol to get the same data that DevTools gets. The underlying protocol method is called Performance.getMetrics. I'm not familiar with Selenium, but it should be possible to hook into the CDP, somehow.

You can also automate this with Puppeteer. I provide an example of using Puppeteer to access DevTools features in Using DevTools Features Without Opening DevTools.