python--boto3 之与dynamoDB 的基本交互，表的备份与恢复

　　最近因工作需要，研究了一下boto3中dynamoDB部分，略有心得，在此总结一下。

　　首先是boto3的安装，在装有python和pip的机器上，运行

sudo pip install boto3

　　官网文档里，boto3提供的与dynamoDB交互的接口有以下几种：

batch_get_item()
batch_write_item()
can_paginate()
create_table()
delete_item()
delete_table()
describe_limits()
describe_table()
describe_time_to_live()
generate_presigned_url()
get_item()
get_paginator()
get_waiter()
list_tables()
list_tags_of_resource()
put_item()
query()
scan()
tag_resource()
untag_resource()
update_item()
update_table()
update_time_to_live()

　　说白了，就是对表和记录的增、删、查、改。本文主要描述我最近使用的那几个接口。

　　要在python中使用boto3，就得先import boto3。当然，这是废话。为了使用方便，我先写了一个json格式的配置文件，如下：

{
    "region_name":"xxx",
    "aws_access_key_id":"xxx",
    "aws_secret_access_key":"xxx"
}

　　然后封装了一个专门用于操作dynamoDB的类，目前什么都没有

class dynamodb_operation():

　　它需要一个读取json文件的方法：

    def load_json(self,path):
        try:
            with open(path) as json_file:
                data = json.load(json_file)
        except Exception as e:
            print 'ERROR: no such file like ' + path
            exit(-1)
        else:
            return data

　　由于读进来的文件可能不是json格式，我这里就是想让他报个错，然后退出。如果不想让它退出，在except里改改就好了。

　　然后，我希望这个类有一个私有成员client，在我实例化对象的时候就建立好连接，于是，有了以下初始化方法：

    def __init__(self,path):
        conf = self.load_json(path)
        self.client = boto3.client('dynamodb',region_name=conf['region_name'],aws_access_key_id=conf['aws_access_key_id'], aws_secret_access_key=conf['aws_secret_access_key'])

　　与之前的配置文件是对应的。

　　有了这个基础，就可以封装自己想要使用的方法了。各方法的在官网上的说明就不照搬过来了。

　　　　1、列出dynamoDB中的所有的表

    def list_all_table(self):
        page=1
        LastEvaluationTableName = ""
        while True:
            if page == 1:
                response = self.client.list_tables()
            else:
                response = self.client.list_tables(
                        ExclusiveStartTableName=LastEvaluationTableName
                        )
            TableNames = response['TableNames']
            for table in TableNames:
                print table
            if response.has_key('LastEvaluatedTableName'):
                LastEvaluationTableName = response["LastEvaluatedTableName"]
            else:
                break
            page += 1

　　　　list_table()方法一次最多只能获取100张表的表名，并且在每次返回的时候，key为"LastEvaluatedTableName"的值为最后一张表的表名，可以做为下次请求的时候的参数。这样循环调用，即可获取所有的表名。如果后面没有表了，response里将不会有LastEvaluatedTableName。此处我只是想把表名打印到终端，如果想保存起来，也是可以的。

　　　　2、获取某张表的信息 describe_table()

    def get_table_desc_only(self,table):
        try:
            response = self.client.describe_table(TableName=table)
        except Exception as e:
            print 'ERROR: no such table like ' + table
            exit(-1)
        else:
            return response["Table"]

　　　　此处只是将response["Table"]原原本本地返回，没有做其它处理。

　　　　如果我想知道一张表的大小，可以：

    def get_table_size(self,table):
        response = self.get_table_desc_only(table)
        stastic = {}
        stastic['TableSizeBytes'] = response['TableSizeBytes']
        stastic['ItemCount'] = response['ItemCount']
        return stastic

　　　　如果想知道其它信息，而且是只想知道那些信息的话，也可以写出对应的方法。

　　　　3、创建一张表

    def create_table(self,tablename,keySchema,attributeDefinitions,provisionedThroughput):
        table = self.client.create_table(
                TableName=tablename,
                KeySchema=keySchema,
                AttributeDefinitions=attributeDefinitions,
                ProvisionedThroughput=provisionedThroughput
                )

        # Wait until the table exists.
        self.client.get_waiter('table_exists').wait(TableName=tablename)

        response = self.client.describe_table(TableName=tablename)
        print response

　　　　这是在创建一张没有索引的表。创表需要时间，所以使用了get_waiter()方法。

　　　　4、插入数据

    def put_item(self,tableName,item):
        try:
            self.client.put_item(
                    TableName=tableName,
                    Item=item
                    )
        except Exception as e:
            print 'ERROR: put item fail. msg: ' + str(e)
            exit(-1)
        else:
            return

　　　　封装的此方法需要传入的是一个格式正确的json，并且key要与表对应。比如：

{'uid':{'N':'999'},'aid':{'N':'999'},'sid':{'N':'999'},'ksid':{'N':'999'}}

　　　　5、删表

    def delete_table(self,table):
        try:
            self.client.delete_table(
                    TableName=table
                    )   
        except Exception as e:
            print 'ERROR: delete table ' + table + ' fail. msg: ' + str(e)
        else:
            print 'delete table ' + table + ' succ'

　　其它方法不多说了。接下来就是表的备份与恢复。要做到什么程度呢，备份的时候，保存好表的结构，大小，以及所有条目，包括索引，恢复的时候，要能建一张一模一样的表，并把数据灌进去。

　　首先是备份表的结构。为了方便恢复表，对describe_table()方法的response进行了处理，同时对init方法进行修改：

    def __init__(self,path):
        conf = self.load_json(path)
        self.client = boto3.client('dynamodb',region_name=conf['region_name'],aws_access_key_id=conf['aws_access_key_id'], aws_secret_access_key=conf['aws_secret_access_key'])
        self.conf_path = path 
        self.items = ['TableName','AttributeDefinitions','KeySchema','LocalSecondaryIndexes','GlobalSecondaryIndexes','ProvisionedThroughput','StreamSpecification']

　　items里为创表时create_table()方法中的所有参数，其中，TableName，AttributeDefinitions，KeySchema，ProvisionedThroughput四项是创表时必传参数，另外三项为选传。同样地，describe_table()方法的response中，这四项也是一定存在的。故：

    def get_SecondaryIndexes_desc(self,content):
        result = []
        for sub_item in content:
            sub_content = {}
            sub_content['IndexName'] = sub_item['IndexName']
            sub_content['KeySchema'] = sub_item['KeySchema']
            sub_content['Projection'] = sub_item['Projection']
            result.append(sub_content)
        return result

　　LocalSecondaryIndexes与GlobalSecondaryIndexes都是列表，所以默认不存在的项直接赋值一个空列表。

    def get_table_desc_for_create_table(self,table):
        response = self.get_table_desc_only(table)
        result = {}
        for item in self.items:
            try:
                content = response[item]
            except Exception as e:
                continue
            else:
                if item == 'TableName':
                    if content != table:
                        print 'ERROR: dynamoDB get table desc error'
                        exit(-1)
                    result[item] = content

                elif item == 'LocalSecondaryIndexes' or item == 'GlobalSecondaryIndexes':
                    result[item] = self.get_SecondaryIndexes_desc(content)
                    continue

                elif item == 'ProvisionedThroughput':
                    continue

                else:
                    result[item] = content
                    continue 

        return json.dumps(result)

　　由于表的阈值不是固定的，所以不做保存。在创表的时候直接设置成一个固定的值即可。

　　对应地，恢复表的方法们：

    def get_item_desc(self,item,content):
        try:
            result = content[item]
        except Exception as e:
                result = []
        return result

    def create_table_from_desc(self,path):
        table_desc = self.load_json(path)
        provisionedThroughput={
                'ReadCapacityUnits': 5,
                'WriteCapacityUnits': 5
                }
        tableName = self.get_item_desc('TableName',table_desc)
        attributeDefinitions = self.get_item_desc('AttributeDefinitions',table_desc)
        keySchema = self.get_item_desc('KeySchema',table_desc)
        localSecondaryIndexes = self.get_item_desc('LocalSecondaryIndexes',table_desc)
        globalSecondaryIndexes = self.get_item_desc('GlobalSecondaryIndexes',table_desc)
        streamSpecification = self.get_item_desc('StreamSpecification',table_desc)

        if len(globalSecondaryIndexes):
            for item in globalSecondaryIndexes:
                item['ProvisionedThroughput'] = provisionedThroughput

        try:
            if len(localSecondaryIndexes):
                if len(globalSecondaryIndexes):
                    table = self.client.create_table(
                            TableName=tableName,
                            KeySchema=keySchema,
                            AttributeDefinitions=attributeDefinitions,
                            ProvisionedThroughput=provisionedThroughput,
                            LocalSecondaryIndexes=localSecondaryIndexes,
                            GlobalSecondaryIndexes=globalSecondaryIndexes
                            )
                else:
                    table = self.client.create_table(
                            TableName=tableName,
                            KeySchema=keySchema,
                            AttributeDefinitions=attributeDefinitions,
                            ProvisionedThroughput=provisionedThroughput,
                            LocalSecondaryIndexes=localSecondaryIndexes
                            )
            else:
                if len(globalSecondaryIndexes):
                    table = self.client.create_table(
                            TableName=tableName,
                            KeySchema=keySchema,
                            AttributeDefinitions=attributeDefinitions,
                            ProvisionedThroughput=provisionedThroughput,
                            GlobalSecondaryIndexes=globalSecondaryIndexes
                            )
                else:
                    table = self.client.create_table(
                            TableName=tableName,
                            KeySchema=keySchema,
                            AttributeDefinitions=attributeDefinitions,
                            ProvisionedThroughput=provisionedThroughput
                            )

        except Exception as e:
            print 'ERROR: error desc like file: ' + path + '	msg: ' + str(e)
            exit(-1)

        else:
            # Wait until the table exists.
            self.client.get_waiter('table_exists').wait(TableName=tableName)
    
            response = self.client.describe_table(TableName=tableName)
            print response

　　传入的path为之前保存好的表的结构。由于两个索引非必传，所以写了四个创表的方法。之前尝试过，不存在索引的时候传空列表[]，None，或者()之类，都会报错，只能用这么一样比较笨的方法。由于StreamSpecification我没有用到，所以只是写在这里。

　　由于时间关系，dump和灌表工具直接就使用git_hub中的 dynamo-archive了。不然自己实现一个也是极好的。

　　在考虑备份表的时候，最近是否使用到成为一个判断因素。此处要使用到cloudwatch。

    def get_stastic(self,dimension):
        conf = self.load_json(self.conf_path)
        cw = boto3.client('cloudwatch',region_name=conf['region_name'],aws_access_key_id=conf['aws_access_key_id'], aws_secret_access_key=conf['aws_secret_access_key'])

        stastic={}
        stastic['Write'] = 0
        stastic['Read'] = 0

        # write
        table_stastic = cw.get_metric_statistics(Namespace='AWS/DynamoDB', MetricName='ConsumedWriteCapacityUnits', 
            Dimensions=dimension, 
            StartTime=datetime.utcnow()-timedelta(days=9), EndTime=datetime.utcnow(), 
            Period=900, Statistics=['Sum', 'Maximum'], Unit='Count')['Datapoints']
        if len(table_stastic) > 1:
            for item in table_stastic:
                stastic['Write'] += int(item['Sum'])

        #read
        table_stastic = cw.get_metric_statistics(Namespace='AWS/DynamoDB', MetricName='ConsumedReadCapacityUnits', 
            Dimensions=dimension, 
            StartTime=datetime.utcnow()-timedelta(days=9), EndTime=datetime.utcnow(), 
            Period=900, Statistics=['Sum', 'Maximum'], Unit='Count')['Datapoints']
        
        if len(table_stastic) > 1:
            for item in table_stastic:
                stastic['Read'] += int(item['Sum'])

        return stastic

    def get_table_use(self,table_name):
        dimension = [{'Name': 'TableName', 'Value': table_name}]
        stastic = self.get_stastic(dimension)
        table = self.get_table_desc_only(table_name)
        for index in table.get('GlobalSecondaryIndexes', []):
            if index['IndexStatus'] != 'ACTIVE':
                return
            dimension = [{'Name': 'TableName', 'Value': table_name}, {'Name': 'GlobalSecondaryIndexName', 'Value': index['IndexName']}]
            tmp = self.get_stastic(dimension)
            stastic['Write'] += tmp['Write']
            stastic['Read'] += tmp['Read']

        return stastic

    def check_table_is_use(self,stastic):
        read = stastic['Write']
        write = stastic['Read']
        if read == 0 and write == 0:
            return False
        else:
            return True

　　直接获取了最近9天的总使用量。

　　当然，如果想知道这张表是不是存在的，也是可以的

    def check_table_is_exist(self,table):
        try:
            response = self.client.describe_table(TableName=table)
        except Exception as e: 
            return 0
        else:
            return 1

　　总体写得挺龊的QAQ

　　参考资料：http://boto3.readthedocs.io/en/latest/reference/services/dynamodb.html

　　原始文件 dynamodb_operation.py

  1 #!/usr/bin/python
  2 #-*- encoding: utf-8 -*-
  3 
  4 import boto3
  5 import json
  6 import sys
  7 from datetime import datetime, timedelta
  8 
  9 class dynamodb_operation():
 10     def __init__(self,path):
 11         conf = self.load_json(path)
 12         self.client = boto3.client('dynamodb',region_name=conf['region_name'],aws_access_key_id=conf['aws_access_key_id'], aws_secret_access_key=conf['aws_secret_access_key'])
 13         self.conf_path = path 
 14         self.items = ['TableName','AttributeDefinitions','KeySchema','LocalSecondaryIndexes','GlobalSecondaryIndexes','ProvisionedThroughput','StreamSpecification']
 15 
 16     def load_json(self,path):
 17         try: 
 18             with open(path) as json_file:
 19                 data = json.load(json_file)
 20         except Exception as e:
 21             print 'ERROR: no such file like ' + path
 22             exit(-1)
 23         else:
 24             return data
 25 
 26     def create_table(self,tablename,keySchema,attributeDefinitions,provisionedThroughput):
 27         table = self.client.create_table(
 28                 TableName=tablename,
 29                 KeySchema=keySchema,
 30                 AttributeDefinitions=attributeDefinitions,
 31                 ProvisionedThroughput=provisionedThroughput
 32                 )
 33         
 34         # Wait until the table exists.
 35         self.client.get_waiter('table_exists').wait(TableName=tablename)
 36     
 37         response = self.client.describe_table(TableName=tablename)
 38         print response
 39 
 40     def get_item_desc(self,item,content):
 41         try:
 42             result = content[item]
 43         except Exception as e:
 44                 result = []
 45         return result
 46 
 47     def create_table_from_desc(self,path):
 48         table_desc = self.load_json(path)
 49         provisionedThroughput={
 50                 'ReadCapacityUnits': 5,
 51                 'WriteCapacityUnits': 5
 52                 }
 53         tableName = self.get_item_desc('TableName',table_desc)
 54         attributeDefinitions = self.get_item_desc('AttributeDefinitions',table_desc)
 55         keySchema = self.get_item_desc('KeySchema',table_desc)
 56         localSecondaryIndexes = self.get_item_desc('LocalSecondaryIndexes',table_desc)
 57         globalSecondaryIndexes = self.get_item_desc('GlobalSecondaryIndexes',table_desc)
 58         streamSpecification = self.get_item_desc('StreamSpecification',table_desc)
 59 
 60         if len(globalSecondaryIndexes):
 61             for item in globalSecondaryIndexes:
 62                 item['ProvisionedThroughput'] = provisionedThroughput
 63 
 64         try:
 65             if len(localSecondaryIndexes):
 66                 if len(globalSecondaryIndexes):
 67                     table = self.client.create_table(
 68                             TableName=tableName,
 69                             KeySchema=keySchema,
 70                             AttributeDefinitions=attributeDefinitions,
 71                             ProvisionedThroughput=provisionedThroughput,
 72                             LocalSecondaryIndexes=localSecondaryIndexes,
 73                             GlobalSecondaryIndexes=globalSecondaryIndexes
 74                             )
 75                 else:
 76                     table = self.client.create_table(
 77                             TableName=tableName,
 78                             KeySchema=keySchema,
 79                             AttributeDefinitions=attributeDefinitions,
 80                             ProvisionedThroughput=provisionedThroughput,
 81                             LocalSecondaryIndexes=localSecondaryIndexes
 82                             )
 83             else:
 84                 if len(globalSecondaryIndexes):
 85                     table = self.client.create_table(
 86                             TableName=tableName,
 87                             KeySchema=keySchema,
 88                             AttributeDefinitions=attributeDefinitions,
 89                             ProvisionedThroughput=provisionedThroughput,
 90                             GlobalSecondaryIndexes=globalSecondaryIndexes
 91                             )
 92                 else:
 93                     table = self.client.create_table(
 94                             TableName=tableName,
 95                             KeySchema=keySchema,
 96                             AttributeDefinitions=attributeDefinitions,
 97                             ProvisionedThroughput=provisionedThroughput
 98                             )
 99 
100         except Exception as e:
101             print 'ERROR: error desc like file: ' + path + '	msg: ' + str(e)
102             exit(-1)
103 
104         else:
105             # Wait until the table exists.
106             self.client.get_waiter('table_exists').wait(TableName=tableName)
107     
108             response = self.client.describe_table(TableName=tableName)
109             print response
110    
111     def get_table_desc_only(self,table):
112         try:
113             response = self.client.describe_table(TableName=table)
114         except Exception as e: 
115             print 'ERROR: no such table like ' + table 
116             exit(-1)
117         else:
118             return response["Table"]
119 
120     def check_table_is_exist(self,table):
121         try:
122             response = self.client.describe_table(TableName=table)
123         except Exception as e: 
124             return 0
125         else:
126             return 1
127 
128     def get_SecondaryIndexes_desc(self,content):
129         result = []
130         for sub_item in content:
131             sub_content = {}
132             sub_content['IndexName'] = sub_item['IndexName']
133             sub_content['KeySchema'] = sub_item['KeySchema']
134             sub_content['Projection'] = sub_item['Projection']
135             result.append(sub_content)
136         return result
137 
138     def get_table_desc_for_create_table(self,table):
139         response = self.get_table_desc_only(table)
140         result = {}
141         for item in self.items:
142             try:
143                 content = response[item]
144             except Exception as e:
145                 continue
146             else:
147                 if item == 'TableName':
148                     if content != table:
149                         print 'ERROR: dynamoDB get table desc error'
150                         exit(-1)
151                     result[item] = content
152 
153                 elif item == 'LocalSecondaryIndexes' or item == 'GlobalSecondaryIndexes':
154                     result[item] = self.get_SecondaryIndexes_desc(content)
155                     continue
156 
157                 elif item == 'ProvisionedThroughput':
158                     continue
159 
160                 else:
161                     result[item] = content
162                     continue 
163 
164         return json.dumps(result)
165 
166     def get_table_size(self,table):
167         response = self.get_table_desc_only(table)
168         stastic = {}
169         stastic['TableSizeBytes'] = response['TableSizeBytes']
170         stastic['ItemCount'] = response['ItemCount']
171         return stastic
172 
173     def list_all_table(self):
174         page=1
175         LastEvaluationTableName = ""
176         while True:
177             if page == 1:
178                 response = self.client.list_tables()
179             else:
180                 response = self.client.list_tables(
181                         ExclusiveStartTableName=LastEvaluationTableName
182                         )
183             TableNames = response['TableNames']
184             for table in TableNames:
185                 print table
186             if response.has_key('LastEvaluatedTableName'):
187                 LastEvaluationTableName = response["LastEvaluatedTableName"]
188             else: 
189                 break
190             page += 1
191 
192     def get_stastic(self,dimension):
193         conf = self.load_json(self.conf_path)
194         cw = boto3.client('cloudwatch',region_name=conf['region_name'],aws_access_key_id=conf['aws_access_key_id'], aws_secret_access_key=conf['aws_secret_access_key'])
195 
196         stastic={}
197         stastic['Write'] = 0
198         stastic['Read'] = 0
199 
200         # write
201         table_stastic = cw.get_metric_statistics(Namespace='AWS/DynamoDB', MetricName='ConsumedWriteCapacityUnits', 
202             Dimensions=dimension, 
203             StartTime=datetime.utcnow()-timedelta(days=9), EndTime=datetime.utcnow(), 
204             Period=900, Statistics=['Sum', 'Maximum'], Unit='Count')['Datapoints']
205          
206         if len(table_stastic) > 1:
207             for item in table_stastic:
208                 stastic['Write'] += int(item['Sum'])
209 
210         #read
211         table_stastic = cw.get_metric_statistics(Namespace='AWS/DynamoDB', MetricName='ConsumedReadCapacityUnits', 
212             Dimensions=dimension, 
213             StartTime=datetime.utcnow()-timedelta(days=9), EndTime=datetime.utcnow(), 
214             Period=900, Statistics=['Sum', 'Maximum'], Unit='Count')['Datapoints']
215         
216         if len(table_stastic) > 1:
217             for item in table_stastic:
218                 stastic['Read'] += int(item['Sum'])
219 
220         return stastic
221 
222     def get_table_use(self,table_name):
223         dimension = [{'Name': 'TableName', 'Value': table_name}]
224         stastic = self.get_stastic(dimension)
225         table = self.get_table_desc_only(table_name)
226         for index in table.get('GlobalSecondaryIndexes', []):
227             if index['IndexStatus'] != 'ACTIVE':
228                 return
229             dimension = [{'Name': 'TableName', 'Value': table_name}, {'Name': 'GlobalSecondaryIndexName', 'Value': index['IndexName']}]
230             tmp = self.get_stastic(dimension)
231             stastic['Write'] += tmp['Write']
232             stastic['Read'] += tmp['Read']
233 
234         return stastic
235 
236     def check_table_is_use(self,stastic):
237         read = stastic['Write']
238         write = stastic['Read']
239         if read == 0 and write == 0:
240             return False
241         else:
242             return True
243 
244     def delete_table(self,table):
245         try:
246             self.client.delete_table(
247                     TableName=table
248                     )
249         except Exception as e:
250             print 'ERROR: delete table ' + table + ' fail. msg: ' + str(e)
251         else:
252             print 'delete table ' + table + ' succ'
253 
254     def list_dynamodb_conf(self):
255         conf = self.load_json(self.conf_path)
256         print 'region_name=' + '"' + conf['region_name'] + '"'
257         print 'aws_access_key_id=' + '"' + conf['aws_access_key_id'] + '"'
258         print 'aws_secret_access_key=' + '"' + conf['aws_secret_access_key'] + '"'
259 
260     def put_item(self,tableName,item):
261         try:
262             self.client.put_item(
263                     TableName=tableName,
264                     Item=item
265                     )
266         except Exception as e:
267             print 'ERROR: put item fail. msg: ' + str(e)
268             exit(-1)
269         else:
270             return
271 
272     def put_items(self,tableName,item_path):
273         for item in open(item_path):
274             self.put_item(tableName,eval(item))
275 
276 if __name__ == "__main__":
277     if len(sys.argv) < 2:
278         print "cmd                                  args"
279         print "list_all_table"
280         print "list_dynamodb_conf"
281         print "get_table_desc_for_create_table      table"
282         print "get_table_desc_only                  table"
283         print "get_table_size                       table"
284         print "create_table_from_desc               table_desc_file"
285         print "check_table_is_exist                 table" 
286         print "get_table_use                        table"
287         print "delete_table                         table               password"
288         print "put_item                             table               item(json)"
289         print "put_items                            table               item_file_path"
290         exit(-1)
291 
292     db = dynamodb_operation('../conf/dynamoDB.conf')
293 
294     cmd = str(sys.argv[1])
295     if len(sys.argv) == 2:
296         if cmd == 'list_all_table':
297             db.list_all_table()
298         if cmd == 'list_dynamodb_conf':
299             db.list_dynamodb_conf()
300 
301     if len(sys.argv) == 3:
302         if cmd == 'get_table_desc_for_create_table':
303             table = str(sys.argv[2])
304             print db.get_table_desc_for_create_table(table)
305 
306         if cmd == 'get_table_desc_only':
307             table = str(sys.argv[2])
308             print db.get_table_desc_only(table)
309 
310         if cmd == 'check_table_is_exist':
311             table = str(sys.argv[2])
312             print db.check_table_is_exist(table) 
313 
314         if cmd == 'get_table_size':
315             table = str(sys.argv[2])
316             print db.get_table_size(table)
317 
318         if cmd == 'create_table_from_desc':
319             desc_file_path = str(sys.argv[2])
320             db.create_table_from_desc(desc_file_path)
321 
322         if cmd == 'get_table_use':
323             table = str(sys.argv[2])
324             stastic = db.get_table_use(table)
325             print stastic 
326             print db.check_table_is_use(stastic)
327 
328 
329     if len(sys.argv) == 4:
330         if cmd == 'delete_table':
331             table = str(sys.argv[2])
332             password = str(sys.argv[3])
333             if password == 'password':
334                 db.delete_table(table)
335             else:
336                 print 'ERROR: password error!'
337                 exit(-1)
338 
339         if cmd == 'put_item':
340             table = str(sys.argv[2])
341             tmp = str(sys.argv[3])
342             item = eval(tmp)
343             db.put_item(table,item)
344 
345         if cmd == 'put_items':
346             table = str(sys.argv[2])
347             item_file_path = str(sys.argv[3])
348             db.put_items(table,item_file_path)

View Code

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原文地址：https://www.cnblogs.com/chinxi/p/7149939.html

python--boto3 之 与dynamoDB 的基本交互，表的备份与恢复

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