I would like to write the following data group to Dynamodb.
There are about 100 data. Since images are not necessarily required, there is a mixture with and without the image_url element.
(questionsList.json)
{
"q_id" : "001",
"q_body" : "Where is the capital of the United States?",
"q_answer" : "Washington, D.C.",
"image_url" : "/Washington.jpg",
"keywords" : [
"UnitedStates",
"Washington"
]
},
{
"q_id" : "002",
"q_body" : "Where is the capital city of the UK?",
"q_answer" : "London",
"image_url" : "",
"keywords" : [
"UK",
"London"
]
},
Since it is the writing test phase, Dynamodb to write to is prepared in localhost:8000 using the serverless-dynamodb-local plugin of the serverless framework, not the production environment.
In order to write the above JSON data to this Dynamodb, I wrote the following code in Boto 3 (AWS SDK for Python).
from __future__ import print_function
import boto3
import codecs
import json
dynamodb = boto3.resource('dynamodb', region_name='us-east-1', endpoint_url="http://localhost:8000")
table = dynamodb.Table('questionListTable')
with open("questionList.json", "r", encoding='utf-8') as json_file:
items = json.load(json_file)
for item in items:
q_id = item['q_id']
q_body = item['q_body']
q_answer = item['q_answer']
image_url = item['image_url']
keywords = item['keywords']
print("Adding detail:", q_id, q_body)
table.put_item(
Item={
'q_id': q_id,
'q_body': q_body,
'q_answer': q_answer,
'image_url': image_url,
'keywords': keywords,
}
)
When this code is executed, the following error occurs in the null character part.
botocore.exceptions.ClientError: An error occurred (ValidationException) when calling the PutItem operation: One or more parameter values were invalid: An AttributeValue may not contain an empty string
Apparently it seems to be caused by JSON 's null character.
If you exclude the image_url containing the null character from the target of writing as below, the writing is completed without any problem.
from __future__ import print_function
import boto3
import codecs
import json
dynamodb = boto3.resource('dynamodb', region_name='us-east-1', endpoint_url="http://localhost:8000")
table = dynamodb.Table('questionListTable')
with open("questionList.json", "r", encoding='utf-8') as json_file:
items = json.load(json_file)
for item in items:
q_id = item['q_id']
q_body = item['q_body']
q_answer = item['q_answer']
#image_url = item['image_url']
keywords = item['keywords']
print("Adding detail:", q_id, q_body)
table.put_item(
Item={
'q_id': q_id,
'q_body': q_body,
'q_answer': q_answer,
#'image_url': image_url,
'keywords': keywords,
}
)
Since DynamoDB is NoSQL, there may be other methods that make good use of the characteristics, but how to correct the code to write the above data ignoring empty characters? I would like to say "if image_url exists, write it if it does not, ignore it."
Thank you.