Fix issue with some circular or unnecessary imports.

PyFunceble/config/loader.py

@@ -65,13 +65,11 @@
 import PyFunceble.cli.storage
 import PyFunceble.storage
 from PyFunceble.config.compare import ConfigComparison
-from PyFunceble.downloader.iana import IANADownloader
-from PyFunceble.downloader.public_suffix import PublicSuffixDownloader
-from PyFunceble.downloader.user_agents import UserAgentsDownloader
 from PyFunceble.helpers.dict import DictHelper
 from PyFunceble.helpers.environment_variable import EnvironmentVariableHelper
 from PyFunceble.helpers.file import FileHelper
 from PyFunceble.helpers.merge import Merge
+from PyFunceble.utils.system import LateImport
 
 
 class ConfigLoader:
@@ -294,12 +292,16 @@ def install_missing_infrastructure_files(
 
         return self
 
-    @classmethod
+    @LateImport(
+        "PyFunceble.downloader.iana<-IANADownloader",
+        "PyFunceble.downloader.public_suffix<-PublicSuffixDownloader",
+        "PyFunceble.downloader.user_agents<-UserAgentsDownloader",
+    )
     def download_dynamic_infrastructure_files(
-        cls,
+        self,
     ) -> "ConfigLoader":
         """
-        Downloads all the dynamicly (generated) infrastructure files.
+        Downloads all the dynamically (generated) infrastructure files.
 
         .. note::
             Downloaded if missing:
@@ -309,7 +311,8 @@ def download_dynamic_infrastructure_files(
 
         ## pragma: no cover ## Underlying download methods already tested.
 
-        if not cls.is_already_loaded():
+        if not self.is_already_loaded():
+            # pylint: disable=undefined-variable # LateImport
             IANADownloader().start()
             PublicSuffixDownloader().start()
             UserAgentsDownloader().start()

PyFunceble/downloader/base.py

@@ -53,10 +53,10 @@
 import datetime
 import os
 from typing import Optional
-import importlib
 
 import PyFunceble.downloader.exceptions
 import PyFunceble.exceptions
+import PyFunceble.factory
 import PyFunceble.storage
 from PyFunceble.helpers.dict import DictHelper
 from PyFunceble.helpers.download import DownloadHelper
@@ -73,7 +73,6 @@ class DownloaderBase:
     the download mechanism but also the generation or update of that JSON file.
     """
 
-
     DOWNTIME_INDEX: Optional[str] = None
     """
     Used to set/track the download time of the current file.
@@ -277,18 +276,16 @@ def start(self) -> None:
         Starts the download process.
         """
 
-
         if self.authorized and self.is_last_download_expired():
             if not hasattr(self, "destination") or not self.destination:
                 raise PyFunceble.downloader.exceptions.NoDownloadDestinationGiven()
 
             if not hasattr(self, "download_link") or not self.download_link:
                 raise PyFunceble.downloader.exceptions.NoDownloadLinkGiven()
 
-            importlib.import_module("PyFunceble.factory")
-
             if DownloadHelper(
-                self.download_link, session=PyFunceble.factory.Requester
+                self.download_link,
+                session=PyFunceble.factory.Requester,
             ).download_text(destination=self.destination):
                 self.set_current_downtime()
                 self.save_all_downtimes()

PyFunceble/query/dns/nameserver.py

@@ -58,7 +58,6 @@
 import PyFunceble.facility
 import PyFunceble.storage
 from PyFunceble.checker.syntax.domain import DomainSyntaxChecker
-from PyFunceble.checker.syntax.url import URLSyntaxChecker
 from PyFunceble.converter.url2netloc import Url2Netloc
 
 
@@ -79,13 +78,13 @@ class Nameservers:
 
     protocol: Optional[str] = None
 
-    domain_syntax_checker: DomainSyntaxChecker = DomainSyntaxChecker()
-    url_syntax_checker: URLSyntaxChecker = URLSyntaxChecker()
+    domain_syntax_checker: Optional[DomainSyntaxChecker] = None
     url2netloc: Url2Netloc = Url2Netloc()
 
     def __init__(
         self, nameserver: Optional[List[str]] = None, protocol: str = "TCP"
     ) -> None:
+        self.domain_syntax_checker = DomainSyntaxChecker()
         self.protocol = protocol
 
         if nameserver is not None:
@@ -125,8 +124,7 @@ def split_nameserver_from_port(
             return ":".join(splitted[:-1]), default_port
         return nameserver, default_port
 
-    @classmethod
-    def get_ip_from_nameserver(cls, nameserver: str) -> List[str]:
+    def get_ip_from_nameserver(self, nameserver: str) -> List[str]:
         """
         Given a nameserver, this method resolve it in order to get the
         IP to contact.
@@ -141,7 +139,7 @@ def get_ip_from_nameserver(cls, nameserver: str) -> List[str]:
 
         result = []
 
-        if cls.domain_syntax_checker.set_subject(nameserver).is_valid():
+        if self.domain_syntax_checker.set_subject(nameserver).is_valid():
             try:
                 result.extend(
                     [

PyFunceble/query/dns/query_tool.py

@@ -96,7 +96,7 @@ class DNSQueryTool:
         x.name: x.value for x in dns.rdatatype.RdataType
     }
 
-    nameservers: Nameservers = Nameservers()
+    nameservers: Optional[Nameservers] = None
     _query_record_type: int = dns.rdatatype.RdataType.ANY
 
     _subject: Optional[str] = None
@@ -120,6 +120,8 @@ def __init__(
         trust_server: Optional[bool] = None,
         delay: Optional[bool] = None,
     ) -> None:
+        self.nameservers = Nameservers()
+
         if nameservers is not None:
             self.nameservers.set_nameservers(nameservers)
         else:  # pragma: no cover ## I'm not playing with system resolver.

PyFunceble/query/requests/requester.py

@@ -61,10 +61,10 @@
 
 import PyFunceble.facility
 import PyFunceble.storage
-from PyFunceble.dataset.user_agent import UserAgentDataset
 from PyFunceble.query.dns.query_tool import DNSQueryTool
 from PyFunceble.query.requests.adapter.http import RequestHTTPAdapter
 from PyFunceble.query.requests.adapter.https import RequestHTTPSAdapter
+from PyFunceble.utils.system import LateImport
 
 
 class Requester:
@@ -523,6 +523,7 @@ def get_timeout(self) -> float:
 
         return self.timeout
 
+    @LateImport("PyFunceble.dataset.user_agent<-UserAgentDataset")
     def get_session(self) -> requests.Session:
         """
         Provides a new session.
@@ -551,6 +552,7 @@ def get_session(self) -> requests.Session:
             ),
         )
 
+        # pylint: disable=undefined-variable # LateImport
         custom_headers = {"User-Agent": UserAgentDataset().get_latest()}
 
         session.headers.update(custom_headers)