Support maxrequestspersecond less than one

doc/src/man/linkcheckerrc.rst

@@ -90,7 +90,8 @@ checking
 **maxrequestspersecond=**\ *NUMBER*
     Limit the maximum number of HTTP requests per second to one host.
     The average number of requests per second is approximately one third of the
-    maximum. To use values greater than 10, the HTTP server must return a
+    maximum. Values less than 1 and at least 0.001 can be used.
+    To use values greater than 10, the HTTP server must return a
     "LinkChecker" response header.
     The default is 10.
     Command line option: none

linkcheck/configuration/confparse.py

@@ -86,6 +86,24 @@ class LCConfigParser(RawConfigParser):
         if self.has_option(section, option):
             self.config[option] = self.getboolean(section, option)
 
+    def read_float_option(self, section, option, key=None, min=None, max=None):
+        """Read a float option."""
+        if self.has_option(section, option):
+            num = self.getfloat(section, option)
+            if min is not None and num < min:
+                raise LinkCheckerError(
+                    _("invalid value for %s: %d must not be less than %d")
+                    % (option, num, min)
+                )
+            if max is not None and num < max:
+                raise LinkCheckerError(
+                    _("invalid value for %s: %d must not be greater than %d")
+                    % (option, num, max)
+                )
+            if key is None:
+                key = option
+            self.config[key] = num
+
     def read_int_option(self, section, option, key=None, min=None, max=None):
         """Read an integer option."""
         if self.has_option(section, option):
@@ -178,7 +196,7 @@ class LCConfigParser(RawConfigParser):
         self.read_int_option(section, "recursionlevel", min=-1)
         self.read_string_option(section, "nntpserver")
         self.read_string_option(section, "useragent")
-        self.read_int_option(section, "maxrequestspersecond", min=1)
+        self.read_float_option(section, "maxrequestspersecond", min=0.001)
         self.read_int_option(section, "maxnumurls", min=0)
         self.read_int_option(section, "maxfilesizeparse", min=1)
         self.read_int_option(section, "maxfilesizedownload", min=1)

tests/configuration/data/config0.ini

@@ -12,6 +12,7 @@ debugmemory=1
 localwebroot=foo
 sslverify=/path/to/cacerts.crt
 maxnumurls=1000
+maxrequestspersecond=0.1
 maxrunseconds=1
 maxfilesizeparse=100
 maxfilesizedownload=100

tests/configuration/test_config.py

@@ -55,6 +55,7 @@ class TestConfig(unittest.TestCase):
         self.assertEqual(config["localwebroot"], "foo")
         self.assertEqual(config["sslverify"], "/path/to/cacerts.crt")
         self.assertEqual(config["maxnumurls"], 1000)
+        self.assertEqual(config["maxrequestspersecond"], 0.1)
         self.assertEqual(config["maxrunseconds"], 1)
         self.assertEqual(config["maxfilesizeparse"], 100)
         self.assertEqual(config["maxfilesizedownload"], 100)