From f6deda77ff3446d3868e317639fd328171547165 Mon Sep 17 00:00:00 2001
From: Cmatrix1 <sadeghmajidi980@gmail.com>
Date: Tue, 19 Sep 2023 18:06:46 +0330
Subject: [PATCH] =?UTF-8?q?=E2=9C=A8=20Add=20abstraction=20for=20the=20pro?=
 =?UTF-8?q?cess=20would=20be=20unaware=20of=20what=20component=20is=20Spid?=
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---
 fastcrawler/core/contracts.py | 24 ++++++++++++++++++++++++
 fastcrawler/core/spider.py    |  3 ++-
 2 files changed, 26 insertions(+), 1 deletion(-)
 create mode 100644 fastcrawler/core/contracts.py

diff --git a/fastcrawler/core/contracts.py b/fastcrawler/core/contracts.py
new file mode 100644
index 0000000..5e48130
--- /dev/null
+++ b/fastcrawler/core/contracts.py
@@ -0,0 +1,24 @@
+from abc import ABC, abstractmethod
+
+
+class ProcessItem(ABC):
+
+    @property
+    def instances(self) -> list["ProcessItem"]:
+        if not hasattr(self, "_instances"):
+            self._instances = [self]
+        return self._instances
+
+    def __rshift__(self, other: "ProcessItem") -> "ProcessItem":
+        """
+        leveraged RSHIFT method for magic in flow >>
+        objA >> objB >> objC >> objD
+        """
+        self.instances.append(other)
+        setattr(other, "instances", self.instances)
+        return other
+
+    @abstractmethod
+    async def start(self):
+        ...
+
diff --git a/fastcrawler/core/spider.py b/fastcrawler/core/spider.py
index 41b6254..dcc3ac7 100644
--- a/fastcrawler/core/spider.py
+++ b/fastcrawler/core/spider.py
@@ -13,8 +13,9 @@
 from fastcrawler.parsers.schema import BaseModel
 from fastcrawler.utils.injection import _Depends
 
+from .contracts import ProcessItem
 
-class Spider:
+class Spider(ProcessItem):
     """
     Spider class to create the actual spider interface
         so that configuration of each spider can be given