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# Fast API CRUD

```python
from typing import Optional
from fastapi import Body, FastAPI, Response, status, HTTPException
from pydantic import BaseModel
from random import randrange
import psycopg2
from psycopg2.extras import RealDictCursor
import time

app = FastAPI()


class Post(BaseModel):
    title: str
    content: str
    published: bool = True
    rating: Optional[int] = None


while True:
    try:
        conn = psycopg2.connect(host="localhost", database="fastapi",
                                user="postgres", password="admin", cursor_factory=RealDictCursor)
        cursor = conn.cursor()
        print("Database connection successful")
        break
    except Exception as error:
        print("Connection failed")
        print("Error: ", error)
        time.sleep(2)


@app.get("/")
async def root():
    return {"message": "Hello World"}


@app.get("/posts")
def post():
    cursor.execute("SELECT * from posts")
    posts = cursor.fetchall()
    return {"data": posts}


@app.post("/posts", status_code=status.HTTP_201_CREATED)
def create_posts(post: Post):
    cursor.execute("""INSERT INTO posts (title, content, published) VALUES
                   (%s, %s, %s) RETURNING * """,
                   (post.title, post.content, post.published))
    new_post = cursor.fetchone()
    conn.commit()
    return {"data": new_post}


@app.get("/posts/{id}")
def get_post(id: int):
    cursor.execute("""SELECT * from posts WHERE id = %s""", (str(id)))
    post = cursor.fetchone()
    if not post:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND, detail="Post not found")
    return {
        "post_details": post
    }


@app.delete("/posts/{id}", status_code=status.HTTP_204_NO_CONTENT)
def delete_post(id: int):
    cursor.execute("DELETE FROM posts WHERE id = %s RETURNING *", (str(id),))
    deleted_post = cursor.fetchone()
    conn.commit()
    if deleted_post == None:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND, detail=f"{id} not found")
    return Response(status_code=status.HTTP_204_NO_CONTENT)


@app.put("/posts/{id}", status_code=status.HTTP_201_CREATED)
def update_post(id: int, post: Post):
    cursor.execute("""UPDATE posts SET title = %s, content = %s, published = %s
                   WHERE id = %s RETURNING *""", (post.title, post.content,
                                                  post.published, str(id)))
    updated_post = cursor.fetchone()
    conn.commit()
    if updated_post == None:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND, detail=f"{id} not found")
    return {"data": updated_post}

```


---

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