testenv: Allow definition of environment variables for wget execuion

* testenv/README: Added description for new EnvironmentVariable hook
* testenv/conf/environment_variable.py: Added implementation of
EnvironmentVariable hook
* testenv/test/base_test.py: Modified exec_wget() to enable use of
EnvironmentVariable hook

Added new test hook called EnvironmentVariables, for defining environment
variables when wget is executed in tests. This is handy for testing
environment variables, which are accepted by wget.

Signed-off-by: Tomas Hozza <thozza@redhat.com>

testenv/README

@@ -224,6 +224,9 @@ executed. The currently supported options are:
     file. While all Download URL's are passed to Urls, a notable exception is
     when in-url authentication is used. In such a case, the URL is specified in
     the WgetCommands string.
+    * EnvironmentVariables: A dictionary with key-value items, which will be
+    defined as environment variables during the execution of wget command in
+    test.
 
 Post-Test Hooks:
 ================================================================================

testenv/conf/environment_variables.py

@@ -0,0 +1,14 @@
+from conf import hook
+
+""" Test Option: EnvironmentVariables
+This hook is used to define environment variables used for execution of wget
+command in test."""
+
+
+@hook(alias='EnvironmentVariables')
+class URLs:
+    def __init__(self, envs):
+        self.envs = envs
+
+    def __call__(self, test_obj):
+        test_obj.envs.update(**self.envs)

testenv/test/base_test.py

@@ -51,6 +51,7 @@ class BaseTest:
 
         self.wget_options = ''
         self.urls = []
+        self.envs = dict()
 
         self.tests_passed = True
         self.ready = False
@@ -97,12 +98,15 @@ class BaseTest:
         cmd_line = self.gen_cmd_line()
         params = shlex.split(cmd_line)
         print(params)
+        envs = {"HOME": os.getcwd()}
+        envs.update(**self.envs)
+        print(envs)
 
         if os.getenv("SERVER_WAIT"):
             time.sleep(float(os.getenv("SERVER_WAIT")))
 
         try:
-            ret_code = call(params, env={"HOME": os.getcwd()})
+            ret_code = call(params, env=envs)
         except FileNotFoundError:
             raise TestFailed("The Wget Executable does not exist at the "
                              "expected path.")