Boto 不会将 s3 文件保存到 AWS Lambda 上的光盘

Question

我正在开发一个模块，该模块从我的 MySQL 数据库中获取有关图像序列的信息，然后使用 boto 库将它们下载到 Lambda 本地。之后，它应该做一些图像处理，但我还没有完成。

我不断收到的错误很奇怪。在（我相信）它下载了第一张图片之后，它说它不存在 file/directory:

    Traceback (most recent call last): File "/var/task/module.py", line 41, in lambda_handler key.get_contents_to_filename(string) 

File "/var/task/boto/s3/key.py", line 1714, in get_contents_to_filename os.remove(filename) OSError: [Errno 2] No such file or directory: '1.png'

我的代码中的第 41 行位于此处：

# Download and Save all of the cropped images for this company  
count = 1
files_list = []
for image in cropped_images:
    key = bucket.get_key(image)
    string = str(count) + '.png'
    key.get_contents_to_filename(string)
    files_list.append(string) 
    count += 1
print("should be done downloading all of the pictures from S3 ...")

这是我目前拥有的模块的完整脚本：

from __future__ import print_function
import json, os
import pymysql

import os, glob, subprocess, boto
from boto.s3.connection import S3Connection

conn = pymysql.connect(host='*******', port=3306, user='*****', passwd='******', db='*******')
cur = conn.cursor()

conn = S3Connection('***************','************************')
bucket = conn.get_bucket('**********')

def upload_file(company_friendly, filepath):
    key = bucket.new_key(company_friendly + ".gif")
    key.set_contents_from_filename(filepath)
    key.set_acl('public-read')
    return True

def lambda_handler(event, context):
    ### Grab Company Friendly from DB ###
    cur.execute("SELECT ************ FROM *********** WHERE company_id = %i LIMIT 1" % (event['company_id']))

    company_data = cur.fetchone()
    company_friendly = company_data[0]

    ### Grab all snapshots from DB ###
    cur.execute("SELECT *********** FROM ************ WHERE company_id = %i ORDER BY date ASC" % (event['company_id']))
    snapshot_data = cur.fetchall()  

    cropped_images = []
    for snapshot in snapshot_data:
        cropped_images.append(snapshot[0])

    ### Download and Save all of the cropped images for this company  ###
    count = 1
    files_list = []
    for image in cropped_images:
        key = bucket.get_key(image)
        string = str(count) + '.png'
        key.get_contents_to_filename(string)
        files_list.append(string) #this makes sure that the animated gif compiles the images in order
        count += 1
    print("should be done downloading all of the pictures from S3 ...")

    return(json.dumps({'status_code':200, 'msg':"company friendly name is " + company_friendly}, sort_keys=True))

知道为什么它不保存图像文件吗？我正在使用 Lambda 控制台建议的默认 S3 角色

Answer 1

您可以尝试将行更改为：

string = '/tmp/' + str(count) + '.png'

无法知道您是否对 lambda 计算机的当前目录具有写入权限。但是/tmp会让你写。

发件人：AWS Lambda FAQ

Q: What if I need scratch space on disk for my AWS Lambda function?

Each Lambda function receives 500MB of non-persistent disk space in its own /tmp directory.

Boto 不会将 s3 文件保存到 AWS Lambda 上的光盘

Boto does not save s3 file to disc on AWS Lambda

python

amazon-s3

boto

amazon-web-services

aws-lambda