From 91c33596daf267541a0f389de252c193d9c2c05e Mon Sep 17 00:00:00 2001
From: Joscha <joscha@plugh.de>
Date: Fri, 30 Apr 2021 16:22:14 +0200
Subject: [PATCH] Load crawlers from config file

---
 PFERD/config.py  | 21 +++++++++++++++++++--
 PFERD/crawler.py |  8 +++++++-
 PFERD/pferd.py   | 46 +++++++++++++++++++++++++++++++++++++++++++---
 3 files changed, 69 insertions(+), 6 deletions(-)

diff --git a/PFERD/config.py b/PFERD/config.py
index d71e4d1..d02900d 100644
--- a/PFERD/config.py
+++ b/PFERD/config.py
@@ -1,7 +1,7 @@
 import configparser
 import os
 from pathlib import Path
-from typing import Optional
+from typing import List, Optional, Tuple
 
 from .utils import prompt_yes_no
 
@@ -26,7 +26,6 @@ class Config:
 
     def __init__(self, parser: configparser.ConfigParser):
         self._parser = parser
-        # TODO Load and validate config into dataclasses
 
     @staticmethod
     def _fail_load(path: Path, reason: str) -> None:
@@ -99,3 +98,21 @@ class Config:
             self._fail_dump(path, "That's a directory, not a file")
         except PermissionError:
             self._fail_dump(path, "Insufficient permissions")
+
+    @property
+    def default_section(self) -> configparser.SectionProxy:
+        return self._parser[configparser.DEFAULTSECT]
+
+    def crawler_sections(self) -> List[Tuple[str, configparser.SectionProxy]]:
+        result = []
+        for section_name, section_proxy in self._parser.items():
+            if section_name.startswith("crawler:"):
+                crawler_name = section_name[8:]
+                result.append((crawler_name, section_proxy))
+
+        return result
+
+    @property
+    def working_dir(self) -> Path:
+        pathstr = self.default_section.get("working_dir", ".")
+        return Path(pathstr).expanduser()
diff --git a/PFERD/crawler.py b/PFERD/crawler.py
index 9ceca20..6b1b350 100644
--- a/PFERD/crawler.py
+++ b/PFERD/crawler.py
@@ -8,6 +8,7 @@ from typing import AsyncContextManager, AsyncIterator, Optional
 from rich.markup import escape
 
 from .conductor import ProgressBar, TerminalConductor
+from .config import Config
 from .limiter import Limiter
 from .transformer import RuleParseException, Transformer
 
@@ -17,7 +18,12 @@ class CrawlerLoadException(Exception):
 
 
 class Crawler(ABC):
-    def __init__(self, name: str, section: configparser.SectionProxy) -> None:
+    def __init__(
+            self,
+            name: str,
+            config: Config,
+            section: configparser.SectionProxy,
+    ) -> None:
         """
         Initialize a crawler from its name and its section in the config file.
 
diff --git a/PFERD/pferd.py b/PFERD/pferd.py
index d145ade..131ddc1 100644
--- a/PFERD/pferd.py
+++ b/PFERD/pferd.py
@@ -1,12 +1,52 @@
+from typing import Dict
+
+from rich import print
+from rich.markup import escape
+
 from .config import Config
+from .crawler import Crawler
 from .crawlers import CRAWLERS
 
 
+class PferdLoadException(Exception):
+    pass
+
+
 class Pferd:
     def __init__(self, config: Config):
         self._config = config
+        self._crawlers: Dict[str, Crawler] = {}
+
+    def _load_crawlers(self) -> None:
+        abort = False
+        for name, section in self._config.crawler_sections():
+            print(f"[bold bright_cyan]Loading[/] crawler:{escape(name)}")
+            crawler_type = section.get("type")
+            crawler_constructor = CRAWLERS.get(crawler_type)
+            if crawler_constructor is None:
+                abort = True
+                if crawler_type is None:
+                    print("[red]Error: No type")
+                else:
+                    t = escape(repr(crawler_type))
+                    print(f"[red]Error: Unknown type {t}")
+                continue
+
+            crawler = crawler_constructor(name, self._config, section)
+            self._crawlers[name] = crawler
+
+        if abort:
+            raise PferdLoadException()
 
     async def run(self) -> None:
-        print("Bleep bloop 1")
-        await CRAWLERS["dummy"]("dummy", self._config._parser["dummy"]).run()
-        print("Bleep bloop 2")
+        try:
+            self._load_crawlers()
+        except PferdLoadException:
+            print("[bold red]Could not initialize PFERD properly")
+            exit(1)
+
+        for name, crawler in self._crawlers.items():
+            print()
+            print(f"[bold bright_cyan]Running[/] crawler:{escape(name)}")
+
+            await crawler.run()