Page doesnt load

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Page doesnt load

Postby Eggator » Mon Aug 03, 2020 1:15 am

Hey guys, i have a strong problem.

Got an application where jcef is used to display browser content. It is packaged into a jar with a jcef.jar as external library.

Whenever we try to load a specific page from our intranet there is simply no content displayed (like the browser window doesnt get html content). It does work with other internal sites without any problems. There seem to be some kind of certificate issue going on that the specific page from the webserver.

Everything is displayed fine inside internet explorer or chrome browser. Do you guys have advice how i can proceed from here? I mean i dont get any error or anything.

The setting to ignore certerrors doesnt change anything.

Any help is appriciated
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Re: Page doesnt load

Postby magreenblatt » Mon Aug 03, 2020 10:57 am

What CEF version are you using? Does the page display in the JCEF sample app?
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Re: Page doesnt load

Postby Eggator » Mon Aug 03, 2020 11:19 am

Im not quite sure about the version. It is a jar files which itself contains a cjcef.jar which i am able to kind of debug via remote debugging. (can i somehow tell which version it using?).

The Browser runs as a component of a plugin of an java application. If i create an simple java program which is using the cjcef.jar (extracted from the jar) as external library the page is loaded successfully. If i try to load other pages like our intranet site those pages are loaded successfully as well (even inside the plugin context).

Seems not like an problem inside the coding itself, more like a specific problem to this side, (if used without encryption (http) the side is loaded successfully as well, but we need it encrypted).
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Re: Page doesnt load

Postby magreenblatt » Mon Aug 03, 2020 11:27 am

Im not quite sure about the version.

Load "about:version" in the browser.

If i create an simple java program which is using the cjcef.jar (extracted from the jar) as external library the page is loaded successfully. If used without encryption (http) the side is loaded successfully as well.

You say that the simple java program works, but the more complex java program does not. How do those programs differ with regard to certificate handling? Are you implementing the CefRequestHandler.onCertificateError callback?
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Re: Page doesnt load

Postby magreenblatt » Mon Aug 03, 2020 11:28 am

There seem to be some kind of certificate issue going on that the specific page from the webserver.

What kind of certificate error? Does Google Chrome report any certificate errors when you load the page?
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Re: Page doesnt load

Postby Eggator » Mon Aug 03, 2020 1:00 pm

magreenblatt wrote:Load "about:version" in the browser.

CEF: 3.3396.1775.g5340bb0
Chromium: 67.0.3396.62
OS: Windows
Webkit: 537.36
Javascript 6.7.288.42

magreenblatt wrote:You say that the simple java program works, but the more complex java program does not. How do those programs differ with regard to certificate handling? Are you implementing the CefRequestHandler.onCertificateError callback?

As far as i can tell, the more complex program brings its own JRE using CACERT files from the JRE. In my simple application, im using the SDK (i diddnt even add the websites certifcates to cacert files there). We had a similar issue with a simple http request to the server which requested the configuration via InputStreamReader Request. Via debugging we found out that there was a java.net.ssl.HandshakeException. We added the websites certificate to the cacert files of the JRE and it fixed the communication via InputStreamReader, but unfortunetly it diddnt solve the issue with the CEF Request.

I dont think the CefRequestHandler.onCertificateError callbacks are implemented and since its "compiled" code i cannot implement them on my own inside this environment, thats why i hoped i could solve the issue in my simple program (but yeah the error doesnt exist there).

magreenblatt wrote:What kind of certificate error? Does Google Chrome report any certificate errors when you load the page?

No Google Chrome just loads the page without any problems.
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Re: Page doesnt load

Postby magreenblatt » Mon Aug 03, 2020 2:14 pm

CEF: 3.3396.1775.g5340bb0

That is a very old version (from April 2018) equating to Chromium 67. Perhaps your server is using TLS 1.3 which is only supported by Chromium 70 and newer. I can't explain why it would work with your sample program, if that program is using the same (old) CEF version. I suggest you update to a current/supported CEF version.
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Re: Page doesnt load

Postby Eggator » Tue Aug 04, 2020 2:19 am

magreenblatt wrote:
CEF: 3.3396.1775.g5340bb0

That is a very old version (from April 2018) equating to Chromium 67. Perhaps your server is using TLS 1.3 which is only supported by Chromium 70 and newer. I can't explain why it would work with your sample program, if that program is using the same (old) CEF version. I suggest you update to a current/supported CEF version.


Upgraded it to the newest version.
Had to compile it with with JDK 1.8.0_261 in order to make it work with the used JRE.
Replaced the cjcef.jar file inside the plugin jar file.
Had to add my Build directory with chrome_elf.dll etc. to java library path (is that correct?), since it has crashed otherwise with link error.


Now running
CEF: 84.3.8
Chromium: 84.0.4147.105

Unfortunetly that diddnt help. Same issues.
Browser Window stays white with this one page when used inside the plugin
No Problems displaying the page when used in my small sample program.

Any other suggestions? Or do i need to tell the supplier of the plugin to implement the CefRequestHandler?
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Re: Page doesnt load

Postby magreenblatt » Tue Aug 04, 2020 9:19 am

Sorry, I have no further suggestions. At this point it sounds like an issue with the plugin.
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Re: Page doesnt load

Postby Phylanx » Tue Aug 11, 2020 1:05 am

We had a similar problem with outdated Operating System versions (in specific Windows 7 and Windows Server 2008 R2).
The problem had something to do with GPU acceleration.

If you have the same problem, you would see it in the jcef logs ("Exiting GPU process due to errors during initialization").

See viewtopic.php?f=17&t=17766 for details.
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