Find default browser in Talkbuchet CLI

When Talkbuchet CLI is executed through the Talkbuchet runner the
browser available in the Docker image is automatically found, thus
removing the need to explicitly set it.

If Talkbuchet CLI is executed by other means, or if a remote Selenium
server is used, the browser still needs to be explicitly set.

Signed-off-by: Daniel Calviño Sánchez <danxuliu@gmail.com>

1 files changed, 51 insertions, 7 deletions

diff --git a/docs/Talkbuchet-cli.py b/docs/Talkbuchet-cli.py
index c15f833ca..2d9e030ea 100644
--- a/docs/Talkbuchet-cli.py
+++ b/docs/Talkbuchet-cli.py
@@ -67,7 +67,10 @@ with:
 
 Talkbuchet-cli.py supports launching Chrome and Firefox instances. Nevertheless,
 note that the browser to be used also needs to be supported by the Selenium
-server. The browser to be used needs to be explicitly set with:
+server. When Talkbuchet-cli.py was started through Talkbuchet-run.sh and a
+remote Selenium server is not set the available browser in the container will be
+automatically used. Otherwise the browser to be used needs to be explicitly set
+with:
 >>>> setBrowser(THE-BROWSER-NAME)
 
 A siege can be started in the following way:
@@ -710,6 +713,7 @@ class Talkbuchet:
 
 
 _browser = ''
+_browserDefault = ''
 
 _nextcloudUrl = ''
 _remoteSeleniumUrl = ''
@@ -723,6 +727,41 @@ _token = ''
 _audio = False
 _video = False
 
+def _isValidBrowser():
+    if not _browser:
+        print("Set browser first")
+        return False
+
+    if _remoteSeleniumUrl and _browser == 'default':
+        print("Set an explicit browser name to be used in the remote Selenium instance")
+        return False
+
+    if _browser == 'default' and not _browserDefault:
+        print("Set an explicit browser name, no default browser found")
+        return False
+
+    return True
+
+def _findDefaultBrowser():
+    global _browserDefault
+
+    # Try to get the browser from the Selenium Docker image.
+    try:
+        _browserDefault = Path('/opt/selenium/browser_name').read_text().strip()
+    except:
+        pass
+
+    if _browserDefault:
+        setBrowser('default')
+    else:
+        print('No default browser found, please set the browser to use with setBrowser("chrome") or setBrowser("firefox")')
+
+def _getBrowser():
+    if _browser == 'chrome' or (_browser == 'default' and _browserDefault == 'chrome'):
+        return 'chrome'
+
+    return 'firefox'
+
 def setBrowser(browser):
     """
     Sets the browser to use.
@@ -730,14 +769,18 @@ def setBrowser(browser):
     Supported browsers are "chrome" and "firefox"; the browser needs to be
     available in the Selenium server.
 
+    The special value "default" (which is the default value) can be set to try
+    to find which is the default browser in the Selenium server and use it
+    without having to specify it.
+
     This is used only for the global helper functions and is not taken into
     account if a Talkbuchet wrapper is manually created.
 
-    :param browser: "chrome" or "firefox".
+    :param browser: "default", "chrome" or "firefox".
     """
 
-    if browser != 'chrome' and browser != 'firefox':
-        print('Browser value not valid. Allowed values: "chrome" or "firefox"')
+    if browser != 'default' and browser != 'chrome' and browser != 'firefox':
+        print('Browser value not valid. Allowed values: "default", "chrome" or "firefox"')
         return
 
     global _browser
@@ -852,8 +895,7 @@ _subscribersPerPublisherCount = None
 sieges = []
 
 def _isValidConfiguration():
-    if not _browser:
-        print("Set browser first")
+    if not _isValidBrowser():
         return False
 
     if not _nextcloudUrl:
@@ -905,7 +947,7 @@ def startSiege():
     if not _isValidConfiguration():
         return
 
-    siege = Siege(_browser, _nextcloudUrl, _headless, _remoteSeleniumUrl)
+    siege = Siege(_getBrowser(), _nextcloudUrl, _headless, _remoteSeleniumUrl)
 
     sieges.append(siege)
 
@@ -996,4 +1038,6 @@ def _deleteTalkbuchetInstancesOnExit():
 # are implicitly deleted while exiting the Selenium driver may not cleanly quit.
 atexit.register(_deleteTalkbuchetInstancesOnExit)
 
+_findDefaultBrowser()
+
 print('Full documentation can be shown by calling help(__name__)')