JsonException when trying to read console from firefox

[surli]

🐛 Bug Report

I cannot retrieve the firefox console logs, I get the following JsonException when I try to do so:

Exception in thread "main" org.openqa.selenium.json.JsonException: Unable to determine type from: H. Last 1 characters read: H
Build info: version: '3.141.59', revision: 'e82be7d358', time: '2018-11-14T08:17:03'
System info: host: 'vivat', ip: '127.0.0.1', os.name: 'Linux', os.arch: 'amd64', os.version: '5.3.10-arch1-1', java.version: '1.8.0_232'
Driver info: driver.version: RemoteWebDriver
	at org.openqa.selenium.json.JsonInput.peek(JsonInput.java:122)
	at org.openqa.selenium.json.JsonTypeCoercer.lambda$null$6(JsonTypeCoercer.java:140)
	at org.openqa.selenium.json.JsonTypeCoercer.coerce(JsonTypeCoercer.java:126)
	at org.openqa.selenium.json.Json.toType(Json.java:69)
	at org.openqa.selenium.json.Json.toType(Json.java:55)
	at org.openqa.selenium.json.Json.toType(Json.java:50)
	at org.openqa.selenium.remote.http.W3CHttpResponseCodec.decode(W3CHttpResponseCodec.java:87)
	at org.openqa.selenium.remote.http.W3CHttpResponseCodec.decode(W3CHttpResponseCodec.java:49)
	at org.openqa.selenium.remote.HttpCommandExecutor.execute(HttpCommandExecutor.java:158)
	at org.openqa.selenium.remote.service.DriverCommandExecutor.execute(DriverCommandExecutor.java:83)
	at org.openqa.selenium.remote.RemoteWebDriver.execute(RemoteWebDriver.java:552)
	at org.openqa.selenium.remote.RemoteExecuteMethod.execute(RemoteExecuteMethod.java:35)
	at org.openqa.selenium.remote.RemoteLogs.getRemoteEntries(RemoteLogs.java:81)
	at org.openqa.selenium.remote.RemoteLogs.get(RemoteLogs.java:77)

After debugging on W3CHttpResponseCode#decode, it seems that the exception is thrown because the content of the response is not a JSON but a text/plain that only contains "HTTP method not allowed".

When checking what request has been sent, it seems that the following POST request is performed:

POST /session/81a0b1fc-cc58-468e-9976-3d783c18f1db/log

So I guess there is two issues:

• the command is wrong for Firefox
• the error is not parsed correctly

I don't reproduce on Chrome, only on Firefox.

To Reproduce

Here's the Java method I'm using to reproduce:

// GeckoDriver v0.26.0
System.setProperty("webdriver.gecko.driver", "/home/urli/geckodriver/geckodriver");
FirefoxOptions firefoxOptions = new FirefoxOptions();
LoggingPreferences logPrefs = new LoggingPreferences();
logPrefs.enable(LogType.BROWSER, Level.ALL);

firefoxOptions.setCapability(CapabilityType.LOGGING_PREFS, logPrefs);

WebDriver driver = new FirefoxDriver(firefoxOptions);
driver.get("https://developer.mozilla.org/fr/docs/Web/API/console");
for (LogEntry logEntry : driver.manage().logs().get(LogType.BROWSER)) {
   System.out.println(String.format("[%s] [%s]", logEntry.getLevel(), logEntry.getMessage()));
}
driver.quit();

Detailed steps to reproduce the behavior:

Expected behavior

I expect to see the browser console logs.

Environment

OS: ArchLinux
Browser: Firefox
Browser version: 70.0.1
Browser Driver version: GeckoDriver 0.26.0
Language Bindings version: Java 3.141.59

[barancev]

geckodriver does not support logging at the moment, please follow this issue: mozilla/geckodriver#284

But we'll try to improve the error message to make it more user-friendly.

[barancev]

Fixed by 6a9c546

[lock]

This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.