post files with protection from dublicats

api.py

@@ -0,0 +1,37 @@
+from fastapi import FastAPI, File, UploadFile
+from sqlalchemy import exists
+import hashlib
+import db
+
+def compute_hash(data: bytes, algorithm="sha256") -> str:
+    h = hashlib.new(algorithm)
+    h.update(data)
+    return h.hexdigest()
+
+app = FastAPI()
+
+@app.get("/")
+def root():
+    return {"message": "hiii from sfs"}
+
+
+@app.post("/")
+async def save_file(file: UploadFile = File(...)):
+    contents = await file.read()
+    
+    hash = compute_hash(contents)
+
+    existed_url = db.file_exists(file.size, hash)
+
+    if not existed_url:
+        file_url = db.add_file(file.filename, file.content_type, file.size, hash)
+    
+        with open(f"files/{file.filename}", "wb") as f:
+            f.write(contents)
+        return {"status": "saved", "filename": file_url}
+    else:
+        return {"status": "file_exists", "filename": existed_url}
+
+@app.get("/api/healthchecker")
+def healthchecker():
+    return {"message": "Howdy :3"}

db.py

@@ -0,0 +1,88 @@
+from sqlalchemy import Column, Integer, String
+from sqlalchemy.orm import DeclarativeBase
+from sqlalchemy import create_engine
+from sqlalchemy.orm import Session, sessionmaker
+from sqlalchemy import select
+
+engine = create_engine("sqlite:///example.db")
+session = Session(bind=engine)
+
+class Base(DeclarativeBase): pass
+  
+class File(Base):
+    __tablename__ = "files"
+  
+    id = Column(Integer, primary_key=True, index=True)
+    extension = Column(String, nullable=True)
+    name = Column(String)
+    content_type = Column(String)
+    size = Column(Integer)
+    hash = Column(String)
+
+    def __repr__(self):
+        return f"<File(id={self.id}, extension='{self.extension}', hash='{self.hash}')>"
+
+def to_base36(n: int) -> str:
+    if n < 0:
+        raise ValueError("Only non-negative integers supported")
+
+    chars = "0123456789abcdefghijklmnopqrstuvwxyz"
+    if n == 0:
+        return "0"
+
+    result = []
+    while n > 0:
+        n, rem = divmod(n, 36)
+        result.append(chars[rem])
+    return "".join(reversed(result))
+
+Base.metadata.create_all(bind=engine)
+
+def get_all_files():
+    with Session(autoflush=False, bind=engine) as db:
+        statement = select(File)
+        return db.scalars(statement).all()
+
+def file_exists(size: int, hash_value: str) -> bool:
+    with Session(bind=engine) as db:
+        statement = select(File).where(
+            File.size == size,
+            File.hash == hash_value
+        )
+        
+        existed_file = db.scalars(statement).first()
+
+        if existed_file is None:
+            return None
+
+        url = f"{to_base36(existed_file.id)}"
+        if existed_file.extension:
+            url += f".{existed_file.extension}"
+
+        return url
+
+
+def add_file(filename: str, content_type, size: int, hash):
+    with Session(autoflush=False, bind=engine) as db:
+        new_file = File()
+        if "." in filename:
+            new_file.name, new_file.extension = filename.rsplit(".", 1)
+        else:
+            new_file.name = filename
+            new_file.extension = None
+        new_file.content_type = content_type
+        new_file.size = size 
+        new_file.hash = hash 
+        db.add(new_file)
+        db.commit()
+        url = f"{to_base36(new_file.id)}"
+        if new_file.extension:
+            url += f".{new_file.extension}"
+
+        return url
+        
+if __name__ == "__main__":
+    for i in get_all_files():
+        print(f"{i.id} {i.name}.{i.extension} ({i.hash}) {i.content_type} {i.size}")
+
+