# Path Operations

```python
from fastapi import FastAPI

# Defining the FastAPI() function
app = FastAPI()

# You need to use a decorator to "activate" the FastAPI logic
# Otherwise it's just a plain python function
@app.get("/") # This is a http method (GET)

# The function itself
def root():

# In true pythonic fashion, function will return result
    return {"message": "Hello World"}
```

* Decorator:

```python
@app
```

* Method:

```python
.get
```

* Path:

```python
("/") # Root path
```

![](/files/s9K9of3dH0RYeUrCl2lW)

{% hint style="info" %}
Note: If you make changes to the code, pass in the --reload flag to the uvicorn webserver so it restarts automatically

```python
uvicorn main:app --reload
```

Use this only for the development environment
{% endhint %}

Example of New Path Operation:

```python
# New Path Operation
@app.get("/posts")
def get_posts():
    return {"data": "This is your post"}
```

{% hint style="info" %}
The code will go down the list of paths and find the first one that matches the URL pattern

For Example:

```python
@app.get("/")
def root():
    return {"message": "Hello World"}
    
@app.get("/")
def get_posts():
    return {"data": "This is your post"}
```

* Note that both have the same path ("/")
* Once this goes down the list it will find the root function first
* It will return the first message:

```python
{"message": "Hello World"}
```

So what it looks for is as follows:

* Request GET method
* With the URL: "/"
  {% endhint %}

{% hint style="warning" %}
THE ORDER IN WHICH YOU STRUCTURE YOUR ROUTES/PATH OPERATIONS DOES MATTER!

IT WILL DETERMINE HOW YOUR API WORKS
{% endhint %}

### Resources:

* If you don't know which method to use, [click here](https://developer.mozilla.org/en-US/docs/Web/HTTP/Methods) for HTTP Methods


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