如何使用 Cloud Storage、Firestore 和 Cloud Run 上传和传送图片

如何使用 Cloud Storage、Firestore 和 Cloud Run 上传和传送图片

关于此 Codelab

subject上次更新时间:4月 4, 2025
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1. 简介

在此 Codelab 中,您将学习如何使用 Cloud Storage、Firestore 和 Cloud Run 上传和传送图片。您还将了解如何使用 Google 的客户端库进行身份验证,以便调用 Gemini。

  • 如何将 FastAPI 应用部署到 Cloud Run
  • 如何使用 Google 的客户端库进行身份验证
  • 如何使用 Cloud Run 服务将文件上传到 Cloud Storage
  • 如何读取和写入 Firestore 中的数据
  • 如何在 Cloud Run 服务中从 Cloud Storage 检索和显示图片

2. 设置和要求

设置将在此 Codelab 中全程使用的环境变量。

PROJECT_ID=dogfood-gcf-saraford
REGION
=us-central1
GCS_BUCKET_NAME
=dogfood-gcf-saraford-codelab-wietse-2

SERVICE_NAME
=fastapi-storage-firestore
SERVICE_ACCOUNT
=fastapi-storage-firestore-sa
SERVICE_ACCOUNT_ADDRESS
=$SERVICE_ACCOUNT@$PROJECT_ID.iam.gserviceaccount.com

启用 API

gcloud services enable run.googleapis.com \
                       storage.googleapis.com \
                       firestore.googleapis.com \
                       cloudbuild.googleapis.com \
                       artifactregistry.googleapis.com

创建一个 Cloud Storage 存储分区来存储图片

gsutil mb -p dogfood-gcf-saraford -l us-central1 gs://$GCS_BUCKET_NAME

允许公开访问您可以在网站上上传和显示图片的存储分区:

gsutil iam ch allUsers:objectViewer gs://$GCS_BUCKET_NAME

运行以下命令来创建服务账号:

gcloud iam service-accounts create $SERVICE_ACCOUNT \
   
--display-name="SA for CR $SERVICE_ACCOUNT"

并向该 SA 授予对 Firestore 和 GCS 存储分区的访问权限

gcloud projects add-iam-policy-binding $PROJECT_ID \
   
--member="serviceAccount:$SERVICE_ACCOUNT_ADDRESS" \
   
--role="roles/datastore.user"

gsutil iam ch serviceAccount
:$SERVICE_ACCOUNT_ADDRESS:roles/storage.objectAdmin gs://$GCS_BUCKET_NAME

3. 创建 Firestore 数据库

运行以下命令以创建 Firestore 数据库

gcloud firestore databases create --location=nam5

4. 创建应用

为您的代码创建一个目录。

mkdir codelab-cr-fastapi-firestore-gcs
cd codelab
-cr-fastapi-firestore-gcs

首先,您需要创建一个模板目录,以便创建 html 模板。

mkdir templates
cd templates

创建一个名为 index.html 且包含以下内容的新文件:

<!DOCTYPE html>
<html>
<head>
    <title>Cloud Run Image Upload Demo</title>
    <style>
        body { font-family: sans-serif; padding: 20px; }
        .upload-form { margin-bottom: 20px; padding: 15px; border: 1px solid #ccc; border-radius: 5px; background-color: #f9f9f9; }
        .image-list { margin-top: 30px; }
        .image-item { border-bottom: 1px solid #eee; padding: 10px 0; }
        .image-item img { max-width: 100px; max-height: 100px; vertical-align: middle; margin-right: 10px;}
        .error { color: red; font-weight: bold; margin-top: 10px;}
    </style>
</head>
<body>

    <h1>Upload an Image</h1>
    <p>Files will be uploaded to GCS bucket: <strong>{{ bucket_name }}</strong> and metadata stored in Firestore.</p>

    <div class="upload-form">
        <form action="/upload" method="post" enctype="multipart/form-data">
            <input type="file" name="file" accept="image/*" required>
            <button type="submit">Upload Image</button>
        </form>
        {% if error_message %}
            <p class="error">{{ error_message }}</p>
        {% endif %}
    </div>

    <div class="image-list">
        <h2>Recently Uploaded Images:</h2>
        {% if images %}
            {% for image in images %}
            <div class="image-item">
                <a href="{{ image.gcs_url }}" target="_blank">
                   <img src="{{ image.gcs_url }}" alt="{{ image.filename }}" title="Click to view full size">
                </a>
                <span>{{ image.filename }}</span>
                <small>(Uploaded: {{ image.uploaded_at.strftime('%Y-%m-%d %H:%M:%S') if image.uploaded_at else 'N/A' }})</small><br/>
                <small><a href="{{ image.gcs_url }}" target="_blank">{{ image.gcs_url }}</a></small>
            </div>
            {% endfor %}
        {% else %}
            <p>No images uploaded yet or unable to retrieve list.</p>
        {% endif %}
    </div>

</body>
</html>

现在,在根目录中创建 Python 代码和其他文件

cd ..

创建一个包含以下内容的 .gcloudignore 文件:

__pycache__

创建一个包含以下内容的 main.py 文件:

import os
import datetime
from fastapi import FastAPI, File, UploadFile, Request, Form
from fastapi.responses import HTMLResponse, RedirectResponse
from fastapi.templating import Jinja2Templates
from google.cloud import storage, firestore

# --- Configuration ---
# Get bucket name and firestore collection from Cloud Run env vars
GCS_BUCKET_NAME = os.environ.get("GCS_BUCKET_NAME", "YOUR_BUCKET_NAME_DEFAULT")
FIRESTORE_COLLECTION = os.environ.get("FIRESTORE_COLLECTION", "YOUR_FIRESTORE_DEFAULT")

# --- Initialize Google Client Libraries ---
# These client libraries will use the Application Default Credentials
# for your service account within the Cloud Run environment
storage_client = storage.Client()
firestore_client = firestore.Client()

# --- FastAPI App ---
app = FastAPI()
templates = Jinja2Templates(directory="templates")

# --- Routes ---
@app.get("/", response_class=HTMLResponse)
async def read_root(request: Request):
    """Serves the main upload form."""
   
   
# Query Firestore for existing images to display
   
images = []
   
try:
       
docs = firestore_client.collection(FIRESTORE_COLLECTION).order_by(
           
"uploaded_at", direction=firestore.Query.DESCENDING
       
).limit(10).stream() # Get latest 10 images
       
for doc in docs:
           
images.append(doc.to_dict())
   
except Exception as e:
       
print(f"Warning: Could not fetch images from Firestore: {e}")
       
# Continue without displaying images if Firestore query fails

   
return templates.TemplateResponse("index.html", {
       
"request": request,
       
"bucket_name": GCS_BUCKET_NAME,
       
"images": images # Pass images to the template
   
})

@app.post("/upload")
async def handle_upload(request: Request, file: UploadFile = File(...)):
    """Handles file upload, saves to GCS, and records in Firestore."""
   
if not file:
       
return {"message": "No upload file sent"}
   
elif not GCS_BUCKET_NAME or GCS_BUCKET_NAME == "YOUR_BUCKET_NAME_DEFAULT":
         
return {"message": "GCS Bucket Name not configured."}, 500 # Internal Server Error

   
try:
       
# 1. Upload to GCS
       
# note: to keep the demo code short, there are no file verifications
       
# for an actual real-world production app, you will want to add checks
       
gcs_url = upload_to_gcs(file, GCS_BUCKET_NAME)

       
# 2. Save metadata to Firestore
       
save_metadata_to_firestore(file.filename, gcs_url, FIRESTORE_COLLECTION)

       
# Redirect back to the main page after successful upload
       
return RedirectResponse(url="/", status_code=303) # Redirect using See Other

   
except Exception as e:
       
print(f"Upload failed: {e}")

       
return templates.TemplateResponse("index.html", {
           
"request": request,
           
"bucket_name": GCS_BUCKET_NAME,
           
"error_message": f"Upload failed: {e}",
           
"images": [] # Pass empty list on error or re-query
       
}, status_code=500)

# --- Helper Functions ---
def upload_to_gcs(uploadedFile: UploadFile, bucket_name: str) -> str:
    """Uploads a file to Google Cloud Storage and returns the public URL."""
   
try:
       
bucket = storage_client.bucket(bucket_name)

       
# Create a unique blob name (e.g., timestamp + original filename)
       
timestamp = datetime.datetime.now(datetime.timezone.utc).strftime("%Y%m%d%H%M%S")
       
blob_name = f"{timestamp}_{uploadedFile.filename}"
       
blob = bucket.blob(blob_name)

       
# Upload the file
       
# Reset file pointer just in case
       
uploadedFile.file.seek(0)
       
blob.upload_from_file(uploadedFile.file, content_type=uploadedFile.content_type)

       
print(f"File {uploadedFile.filename} uploaded to gs://{bucket_name}/{blob_name}")
       
return blob.public_url # Return the public URL

   
except Exception as e:
       
print(f"Error uploading to GCS: {e}")
       
raise  # Re-raise the exception for FastAPI to handle

def save_metadata_to_firestore(filename: str, gcs_url: str, collection_name: str):
    """Saves image metadata to Firestore."""
   
try:
       
doc_ref = firestore_client.collection(collection_name).document()
       
doc_ref.set({
           
'filename': filename,
           
'gcs_url': gcs_url,
           
'uploaded_at': firestore.SERVER_TIMESTAMP # Use server timestamp
       
})
       
print(f"Metadata saved to Firestore collection {collection_name}")
   
except Exception as e:
       
print(f"Error saving metadata to Firestore: {e}")
       
# Consider raising the exception or handling it appropriately
       
raise # Re-raise the exception

创建一个包含以下内容的 Dockerfile

# Build stage
FROM python:3.12-slim AS builder

WORKDIR /app

# Install poetry
RUN pip install poetry
RUN poetry self add poetry-plugin-export

# Copy poetry files
COPY pyproject.toml poetry.lock* ./

# Copy application code
COPY . .

# Export dependencies to requirements.txt
RUN poetry export -f requirements.txt --output requirements.txt

# Final stage
FROM python:3.12-slim

WORKDIR /app

# Copy files from builder
COPY --from=builder /app/ .

# Install dependencies
RUN pip install --no-cache-dir -r requirements.txt

# Compile bytecode to improve startup latency
# -q: Quiet mode
# -b: Write legacy bytecode files (.pyc) alongside source
# -f: Force rebuild even if timestamps are up-to-date
RUN python -m compileall -q -b -f .

# Expose port
EXPOSE 8080

# Run the application
CMD ["uvicorn", "main:app", "--host", "0.0.0.0", "--port", "8080"]

并创建了以下 pyproject.toml

[tool.poetry]
name = "cloud-run-fastapi-demo"
version = "0.1.0"
description = "Demo FastAPI app for Cloud Run showing GCS upload and Firestore integration."
authors = ["Your Name <you@example.com>"]
readme = "README.md"

[tool.poetry.dependencies]
python = "^3.12"
fastapi = "^0.110.0"
uvicorn = {extras = ["standard"], version = "^0.29.0"} # Includes python-multipart
google-cloud-storage = "^2.16.0"
google-cloud-firestore = "^2.16.0"
jinja2 = "^3.1.3"
python-multipart = "^0.0.20"

[build-system]
requires = ["poetry-core"]
build-backend = "poetry.core.masonry.api"

5. 部署到 Cloud Run

以下是用于部署到 Cloud Run 的命令。系统会压缩您的代码并将其发送到 Cloud Build,Cloud Build 会使用 Dockerfile 创建映像。

由于这是基于源代码的 Cloud Run 部署,因此在该服务的 Cloud 控制台中,您会看到包含代码的“Source”(源代码)标签页。

gcloud run deploy $SERVICE_NAME \
 --source . \
 --allow-unauthenticated \
 --service-account=$SERVICE_ACCOUNT_ADDRESS \
 --set-env-vars=GCS_BUCKET_NAME=$GCS_BUCKET_NAME \
 --set-env-vars=FIRESTORE_COLLECTION=$FIRESTORE_COLLECTION

6. 测试您的服务

在网络浏览器中打开服务网址,然后上传图片。您会在列表中看到该应用。

7. 更改公开 Cloud Storage 存储分区的权限

如前所述,此 Codelab 使用的是公共 GCS 存储分区。建议您删除该存储分区,或者运行以下命令移除对该存储分区的 allUsers 访问权限:

gsutil iam ch -d allUsers:objectViewer gs://$GCS_BUCKET_NAME

您可以通过运行以下命令来确认已移除 allUsers 访问权限:

gsutil iam get gs://$GCS_BUCKET_NAME

8. 恭喜

恭喜您完成此 Codelab!

所学内容

  • 如何将 FastAPI 应用部署到 Cloud Run
  • 如何使用 Google 的客户端库进行身份验证
  • 如何使用 Cloud Run 服务将文件上传到 Cloud Storage
  • 如何读取和写入 Firestore 中的数据
  • 如何在 Cloud Run 服务中从 Cloud Storage 检索和显示图片

9. 清理

如需删除 Cloud Run 服务,请前往 Cloud Run Cloud 控制台 (https://console.cloud.google.com/run) 并删除该服务。

如需删除 Cloud Storage 存储分区,您可以运行以下命令:

echo "Deleting objects in gs://$GCS_BUCKET_NAME..."
gsutil rm
-r gs://$GCS_BUCKET_NAME/*

echo
"Deleting bucket gs://$GCS_BUCKET_NAME..."
gsutil rb gs
://$GCS_BUCKET_NAME

如果您选择删除整个项目,可以前往 https://console.cloud.google.com/cloud-resource-manager,选择您在第 2 步中创建的项目,然后选择“删除”。如果您删除该项目,则需要在 Cloud SDK 中更改项目。您可以通过运行 gcloud projects list 来查看所有可用项目的列表。