Python azure 函数应用程序无法正确读取 sqlite db 文件

Question

我有一个存储帐户，其容器名为 abc360。该容器中有一个名为 sqlite_db_file 的文件夹。 Sqlite db 文件将被放置在此文件夹中。文件名如下：

ABC100102_2_20230202.db

文件路径如下所示：

abc360/sqlite_db_file/ABC100102_2_20230202.db

存储帐户和容器详细信息：

Storage account: abc360stg
Container: abc360

我在 python 中有一个 azure 函数应用程序，应该在删除文件并将数据从文件复制到 csv 文件并将其上传回同一路径时触发。

所以我创建了一个带有 blob 触发器的函数，function.json 如下所示：

{
  "scriptFile": "__init__.py",
  "bindings": [
   {
     "name": "myblob",
     "type": "blobTrigger",
     "direction": "in",
     "path": "abc360/sqlite_db_file/{name}.db",
     "connection": "abc360stg_STORAGE"
   }
 ]
}

现在我只是想获取数据库文件中的所有表，下面是我的代码：

import logging
import sqlite3
import os
import csv
from azure.functions import InputStream

class DataMigrator:
    def __init__(self, fileName, connection_string):
        self.fileName = fileName
        self.connection_string = connection_string

    def connect_sqlite(self):
        return sqlite3.connect(self.fileName)

    def get_table_names(self, cursor_sqlite):
        logging.info(cursor_sqlite)
        cursor_sqlite.execute("SELECT name FROM sqlite_master;")
        return cursor_sqlite.fetchall()

def main(myblob: InputStream):
    try:
        blob_name = myblob.name.split("/")[-1]
        logging.info(blob_name)
        migrator = DataMigrator(blob_name, connection_string)

        conn_sqlite = migrator.connect_sqlite()
        logging.info("Connected to SQLite database successfully")
        cursor_sqlite = conn_sqlite.cursor()

        tables = migrator.get_table_names(cursor_sqlite)
        logging.info(f"Tables in SQLite file: {tables}")
    
    except Exception as e:
        logging.error(f"Error: {str(e)}")
    finally:
        # Close SQLite connection
        if conn_sqlite:
            conn_sqlite.close()

代码工作正常，它可以很好地连接到 sqlite 数据库文件，但它返回一个表列表的 emprt 数组。当我在本地连接本地驱动器中的文件夹时，它工作正常并列出所有内容。

输出（当数据库文件位于存储帐户中时）：

Tables in SQLite file: []

使用以下代码是因为 myblob.name 返回 abc360/sqlite_db_file/ABC100102_2_20230303.db 而我想要的只是文件名：

myblob.name.split("/")[-1]

我想知道这里是否还需要其他东西来读取存储帐户中的数据库文件？

非常感谢您的帮助。

Answer 1

我尝试使用下面的代码从 Azure 存储 blob 中的 .db 文件获取表列表。

代码：

import logging
import os
import tempfile
import sqlite3
from azure.functions import InputStream

class DataMigrator:
    def __init__(self, file_path):
        self.file_path = file_path

    def connect_sqlite(self):
        return sqlite3.connect(self.file_path)

    def get_table_names(self, cursor_sqlite):
        cursor_sqlite.execute("SELECT name FROM sqlite_master WHERE type='table';")
        return cursor_sqlite.fetchall()

def main(myblob: InputStream):
    try:
        blob_name = os.path.basename(myblob.name)
        logging.info(f"Processing blob: {blob_name}")

        temp_file_path = os.path.join(tempfile.gettempdir(), blob_name)
        with open(temp_file_path, "wb") as temp_file:
            temp_file.write(myblob.read())

        migrator = DataMigrator(temp_file_path)
        conn_sqlite = migrator.connect_sqlite()
        logging.info("Connected to SQLite database successfully")
        cursor_sqlite = conn_sqlite.cursor()

        tables = migrator.get_table_names(cursor_sqlite)
        logging.info(f"Tables in SQLite file: {tables}")

    except Exception as e:
        logging.error(f"Error: {str(e)}")
    finally:
        if conn_sqlite:
            conn_sqlite.close()
        if os.path.exists(temp_file_path):
            os.remove(temp_file_path)

local.settings.json：

{
  "IsEncrypted": false,
  "Values": {
    "AzureWebJobsStorage": "<storage_conne>",
    "FUNCTIONS_WORKER_RUNTIME": "python",
    "kam11funcstr_STORAGE": "<storage_conne>"
  }
}

function.json：

{
  "scriptFile": "__init__.py",
  "bindings": [
    {
      "name": "myblob",
      "type": "blobTrigger",
      "direction": "in",
      "path": "abc360/sqlite_db_file/{name}.db",
      "connection": "kam11funcstr_STORAGE"
    }
  ]
}

输出：

以下 blob 触发器函数代码成功运行，提供容器中 .db 文件中的表列表。

 *  Executing task: .venv\Scripts\activate ; func host start 

Found Python version 3.11.8 (py).

Azure Functions Core Tools
Core Tools Version:       4.0.5382 Commit hash: N/A  (64-bit)
Function Runtime Version: 4.25.3.21264

[2024-03-26T09:35:56.884Z] 0.01s - Debugger warning: It seems that frozen modules are being used, which may
[2024-03-26T09:35:56.888Z] 0.00s - make the debugger miss breakpoints. Please pass -Xfrozen_modules=off
[2024-03-26T09:35:56.893Z] 0.00s - to python to disable frozen modules.
[2024-03-26T09:35:56.897Z] 0.00s - Note: Debugging will proceed. Set PYDEVD_DISABLE_FILE_VALIDATION=1 to disable this validation.       
[2024-03-26T09:35:57.750Z] Worker process started and initialized.

Functions:

        BlobTrigger1: blobTrigger

For detailed output, run func with --verbose flag.
[2024-03-26T09:36:02.866Z] Host lock lease acquired by instance ID '000000000xxxxxxxxxx'.
[2024-03-26T09:36:30.129Z] Executing 'Functions.BlobTrigger1' (Reason='New blob detected(LogsAndContainerScan): abc360/sqlite_db_file/ABC100102_2_20230202.db', Id=fb47edb3-xxxxxxxxxxxxxxxx)
[2024-03-26T09:36:30.133Z] Trigger Details: MessageId: 109019e4-xxxxxxxxxxx, DequeueCount: 1, InsertedOn: 2024-03-26T09:36:28.000+00:00, BlobCreated: 2024-03-26T09:36:26.000+00:00, BlobLastModified: 2024-03-26T09:36:26.000+00:00
[2024-03-26T09:36:30.244Z] Connected to SQLite database successfully
[2024-03-26T09:36:30.244Z] Processing blob: ABC100102_2_20230202.db
[2024-03-26T09:36:30.244Z] Tables in SQLite file: [('users',), ('orders',)]
[2024-03-26T09:36:30.289Z] Executed 'Functions.BlobTrigger1' (Succeeded, Id=fb47edb3xxxxxxxxxxxx, Duration=925ms)