Dados de formulário e envio de arquivos
Processe dados de formulários HTML tradicionais e implemente o envio de arquivos usando os recursos integrados do FastAPI.
Dados de formulário e envio de arquivos é uma aula grátis de FastAPI Backend Development Bootcamp no CoddyKit. Esta é a aula 3 de 4. Você pode ler a aula completa abaixo gratuitamente — depois pratica ao vivo no navegador com um editor de código integrado e um tutor de IA 24/7. Faz parte do caminho de aprendizado de FastAPI Backend Development Bootcamp, e seu progresso é sincronizado entre a web e o app CoddyKit. O curso de FastAPI Backend Development Bootcamp inclui 4 aulas no total.
Partes desta aula ainda não foram traduzidas e aparecem em inglês.
Form Data Basics
When you fill out a web form (like a login or registration page) and click "submit," the data you entered is often sent as form data.
This is a traditional way for browsers to send information to a server, different from sending JSON in a request body.
Form data can be sent in two main ways:
application/x-www-form-urlencoded: For simple key-value pairs.multipart/form-data: Used when files are involved, or for larger, more complex data.
FastAPI's Form Dependency
FastAPI makes handling form data easy using the Form dependency from fastapi.
It works similarly to Query or Path parameters, but it tells FastAPI to expect the data in the request body as form fields.
You import it like this: from fastapi import FastAPI, Form.
Basic Form Endpoint Example
Let's create an endpoint that accepts a username and password as form data. Notice how username and password are explicitly marked with Form(...).
This tells FastAPI to parse them from the form body, not as JSON or query parameters.
from fastapi import FastAPI, Form
import uvicorn
app = FastAPI()
@app.post("/login/")
async def login(username: str = Form(...), password: str = Form(...)):
return {"username": username, "message": "Login successful!"}
if __name__ == "__main__":
uvicorn.run(app, host="0.0.0.0", port=8000)Interacting with Form Data
You can test this endpoint using tools like curl or by creating a simple HTML form. The -d flag in curl sends form data.
Make sure your FastAPI application from the previous scene is running!
curl -X POST "http://127.0.0.1:8000/login/" \
-H "Content-Type: application/x-www-form-urlencoded" \
-d "username=coddy&password=secret"File Uploads Explained
Uploading files (like images, documents, or videos) is a common web task. This type of data is sent using multipart/form-data encoding.
FastAPI provides special tools to handle these uploads efficiently, allowing you to access file contents and metadata.
FastAPI's UploadFile
For file uploads, FastAPI uses the UploadFile class (from fastapi) along with the File dependency.
When you declare a parameter with File(...) and type-hint it as UploadFile, FastAPI handles the file stream.
filename: The name of the uploaded file.content_type: The file's MIME type (e.g.,image/jpeg).file: A SpooledTemporaryFile object, allowing you to read its contents.
from fastapi import FastAPI, File, UploadFile
import uvicorn
app = FastAPI()
@app.post("/uploadfile/")
async def create_upload_file(file: UploadFile = File(...)):
return {"filename": file.filename, "content_type": file.content_type}
if __name__ == "__main__":
uvicorn.run(app, host="0.0.0.0", port=8000)Saving One Uploaded File
After receiving an UploadFile, you can read its content and save it to a local disk or cloud storage. Here's how to save it locally.
Remember to handle potential errors during file operations.
from fastapi import FastAPI, File, UploadFile
import uvicorn
import shutil
import os
app = FastAPI()
# Ensure the 'files' directory exists
os.makedirs("files", exist_ok=True)
@app.post("/uploadandsave/")
async def upload_and_save_file(file: UploadFile = File(...)):
file_location = f"files/{file.filename}"
with open(file_location, "wb+") as file_object:
shutil.copyfileobj(file.file, file_object)
return {"message": f"File '{file.filename}' saved at '{file_location}'"}
if __name__ == "__main__":
uvicorn.run(app, host="0.0.0.0", port=8000)Uploading Many Files
What if you need to upload several files at once? FastAPI supports this by allowing you to define a parameter as a list of UploadFile.
Each file in the list will be an UploadFile object, which you can then process individually.
from fastapi import FastAPI, File, UploadFile
from typing import List
import uvicorn
app = FastAPI()
@app.post("/uploadmultiple/")
async def create_upload_files(files: List[UploadFile] = File(...)):
uploaded_filenames = [file.filename for file in files]
return {"filenames": uploaded_filenames, "message": "Files received!"}
if __name__ == "__main__":
uvicorn.run(app, host="0.0.0.0", port=8000)Saving Multiple Uploads
Similar to single files, you can iterate through the list of UploadFile objects and save each one. This is useful for photo galleries or document uploads.
Always ensure proper error handling and secure file storage practices in a real application.
from fastapi import FastAPI, File, UploadFile
from typing import List
import uvicorn
import shutil
import os
app = FastAPI()
# Ensure the 'files' directory exists
os.makedirs("files", exist_ok=True)
@app.post("/uploadandsavemultiple/")
async def upload_and_save_multiple_files(files: List[UploadFile] = File(...)):
saved_files = []
for file in files:
file_location = f"files/{file.filename}"
with open(file_location, "wb+") as file_object:
shutil.copyfileobj(file.file, file_object)
saved_files.append(file.filename)
return {"message": f"Successfully uploaded: {', '.join(saved_files)}"}
if __name__ == "__main__":
uvicorn.run(app, host="0.0.0.0", port=8000)Form & File Check
You've learned about handling form data and file uploads. Let's test your understanding!
Lesson Summary
Great job! In this lesson, you mastered how to handle traditional form data and robust file uploads in FastAPI.
- We used
Form(...)for simple key-value form fields. - We explored
UploadFileandFile(...)for single and multiple file uploads. - You learned to save uploaded files to your server.
These techniques are crucial for building interactive web applications. Keep practicing!
Perguntas Frequentes
A aula “Dados de formulário e envio de arquivos” é grátis?
Sim — o texto completo de “Dados de formulário e envio de arquivos” é grátis para ler aqui na web. Para praticá-la interativamente (um editor de código integrado e um tutor de IA 24/7) e desbloquear o restante do curso de FastAPI Backend Development Bootcamp, atualize para CoddyKit PRO. O curso de FastAPI Backend Development Bootcamp inclui 4 aulas no total.
O que vou aprender em “Dados de formulário e envio de arquivos”?
Processe dados de formulários HTML tradicionais e implemente o envio de arquivos usando os recursos integrados do FastAPI. Você pratica FastAPI Backend Development Bootcamp com código prático que executa diretamente no navegador, e um tutor de IA 24/7 responde suas dúvidas enquanto trabalha na aula.
Preciso ter experiência prévia para começar FastAPI Backend Development Bootcamp?
Nenhuma experiência prévia é necessária. FastAPI Backend Development Bootcamp no CoddyKit é estruturado para alunos iniciantes até avançados, então você pode começar aqui ou desde o início e aprender no seu ritmo. Esta é a aula 3 de 4.
Quanto tempo leva a aula “Dados de formulário e envio de arquivos”?
A maioria das aulas CoddyKit leva cerca de 5–10 minutos. Cada uma é compacta e interativa, então você faz progresso constante e retoma exatamente de onde parou entre web e app.
Posso escrever e executar código nesta aula de FastAPI Backend Development Bootcamp?
Sim. Cada aula de FastAPI Backend Development Bootcamp inclui um editor de código integrado, então você escreve e executa código real direto no navegador e recebe feedback de IA instantaneamente — nenhuma configuração local necessária.
Todas as aulas deste curso
- Modelos Pydantic para o corpo da requisição
- Modelos de resposta e códigos de status
- Dados de formulário e envio de arquivos
- Cabeçalhos, cookies e respostas personalizadas