如何通过Python代码将Firebase Firestore数据库导出为JSON格式？（无谷歌账号权限场景）

Got it, let's walk through how to export your Firestore database to JSON using your existing service account credentials. We'll handle nested collections, Firestore-specific data types, and preserve document IDs so you can recreate an identical database later.

Step 1: Set Up the Firestore Connection #

First, let's formalize your existing connection code into a standalone script, adding a check to avoid reinitializing the Firebase app multiple times:

import firebase_admin
from firebase_admin import credentials
from firebase_admin import firestore
import json

# Load your service account credentials (paste your actual JSON values here)
service_account_cert = {
    "type": "service_account", 
    "project_id": "...", 
    "private_key_id": "...", 
    "private_key": "-----BEGIN PRIVATE KEY-----\n ...", 
    "client_email": "...@appspot.gserviceaccount.com", 
    "client_id": "...", 
    "auth_uri": "https://accounts.google.com/o/oauth2/auth", 
    "token_uri": "https://oauth2.googleapis.com/token", 
    "auth_provider_x509_cert_url": "https://www.googleapis.com/oauth2/v1/certs", 
    "client_x509_cert_url": "https://www.googleapis.com/robot/v1/metadata/x509/...gserviceaccount.com" 
}

# Initialize Firebase app only once
if not firebase_admin._apps:
    cred = credentials.Certificate(service_account_cert)
    firebase_admin.initialize_app(cred)

# Get Firestore client
db = firestore.client()

Step 2: Recursively Fetch All Data (Including Subcollections) #

Firestore uses a nested collection-document structure, so we need a recursive function to capture every layer. We'll also convert Firestore-specific data types (like Timestamp or GeoPoint) into JSON-serializable formats:

def convert_firestore_value(value):
    """Convert Firestore-native types to JSON-friendly formats"""
    if isinstance(value, firestore.Timestamp):
        return value.to_datetime().isoformat()
    elif isinstance(value, firestore.GeoPoint):
        return {"latitude": value.latitude, "longitude": value.longitude}
    elif isinstance(value, dict):
        return {k: convert_firestore_value(v) for k, v in value.items()}
    elif isinstance(value, list):
        return [convert_firestore_value(item) for item in value]
    else:
        return value

def fetch_collection(collection_ref):
    """Recursively pull all documents and subcollections from a collection"""
    collection_data = {}
    
    # Fetch all documents in the current collection
    docs = collection_ref.stream()
    for doc in docs:
        doc_data = convert_firestore_value(doc.to_dict())
        # Save the document ID to recreate it later
        doc_data["__doc_id__"] = doc.id
        
        # Fetch and process all subcollections for this document
        subcollections = doc.reference.collections()
        subcollection_data = {}
        for subcol in subcollections:
            subcollection_data[subcol.id] = fetch_collection(subcol)
        
        if subcollection_data:
            doc_data["__subcollections__"] = subcollection_data
        
        collection_data[doc.id] = doc_data
    
    return collection_data

# Fetch all top-level collections in the database
exported_data = {}
top_level_collections = db.collections()
for col in top_level_collections:
    exported_data[col.id] = fetch_collection(col)

Step 3: Save the Export to a JSON File #

Finally, write the collected data to a JSON file with readable formatting:

with open("firestore_full_export.json", "w", encoding="utf-8") as export_file:
    json.dump(exported_data, export_file, indent=2, ensure_ascii=False)

print("Success! Database exported to firestore_full_export.json")

Key Details to Note: #

• We store document IDs in __doc_id__ so you can recreate documents with the exact same IDs in your new database.
• Subcollections are grouped under __subcollections__ to preserve the original nested structure.
• Firestore-specific types are converted to JSON-compatible values—you'll need to reverse this conversion when importing to your new database (e.g., turn ISO strings back into Timestamp objects).

内容的提问来源于stack exchange，提问作者SadDeveloepr