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Nifi Issue - writing a JSON file to PutDynamoDb

Nifi Issue - writing a JSON file to PutDynamoDb

Explorer

Hi,

I am new to using nifi. I am trying to use GetFile processor that points to a JSON file to land in the dynamodb table using a PutDynamoDb processor.

Here is the sample structure of the input json file:

{

"messageid": "1",

"field 1": "value 1",

"field 2": "value 2",

"field 3": "value 3",

"field 4": "value 4"

}

However, I am getting an error related to hash key values in the putdynamodb processor. Attached are the screenshots of the error message (1.jpeg) and the configuration settings (2.jpg) for the putdynamodb processor.

I am not sure if I am doing something wrong in the property settings.

Also, I am not sure what values the JSON Document Attribute property expects? I read the documentation but it is unclear.

Any help will be appreciated on the issues

1.jpg

2.jpg

Thanks, Jason

4 REPLIES 4
Highlighted

Re: Nifi Issue - writing a JSON file to PutDynamoDb

Super Guru
@Jason Sphar

as you have configured PutDynamoDB processor as

Hash Key Value

${messageid}

Extract the messageid value from the json record by using EvaluateJsonPath processor and keep as attribute to the flowfile.

92622-screen-shot-2018-10-02-at-62838-pm.png

Then use the matched relationship from EvaluateJsonPath processor to PutDynamoDB processor.

-

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Highlighted

Re: Nifi Issue - writing a JSON file to PutDynamoDb

Explorer
@Shu

Thank you for the response. It is working fine without any errors. However, when I go to the dynamodb table, the entire JSON object from the FlowFile lands under the property set in JSON Document Attribute (in this case, activity).

JSON Input:

{

"messageid": "1",

"application": "value 1",

"datetime": "value 2",

"dev": "value 3",

"activity": "value 4"

}

For example, I have the below in a field called activity in dynamodb table. Attached is a screenshot of the table in dynamodb (3.jpg)

Output in DynamoDB table under a field called 'activity':

{

"application" : {

"S" : "value 1"

},

"datetime" : {

"S" : "value 2"

},

"dev" : {

"S" : "value 3"

},

"activity" : {

"S" : "value 4"

},

"messageid" : {

"S" : "1"

}

}

I want the JSON contents of the FlowFile to land in DynamoDB as a record with a messageid and 4 fields with their respective values. I don't know if this is a bug or if I am using it incorrectly. Is there any workaround? Thanks!

3.jpg

Highlighted

Re: Nifi Issue - writing a JSON file to PutDynamoDb

Explorer

@Shu

Thank you for the response. It is working fine without any errors. However, when I go to the dynamodb table, the entire JSON object from the FlowFile lands under the property set in JSON Document Attribute (in this case, activity) for the PutDynamoDB processor. Attached is a screenshot of the table in dynamodb (3.jpg) 3.jpg

Sample JSON Input:

{

"messageid": "1",

"application": "value 1",

"datetime": "value 2",

"dev": "value 3",

"activity": "value 4"

}

Sample Output in DynamoDB table under a single field called 'activity':

{

"application" : {

"S" : "value 1"

},

"datetime" : {

"S" : "value 2"

},

"dev" : {

"S" : "value 3"

},

"activity" : {

"S" : "value 4"

},

"messageid" : {

"S" : "1"

}

}

I want the JSON contents of the FlowFile to land in DynamoDB as a record with a messageid and 4 fields with their respective values.

I don't know if this is a bug or if I am using it incorrectly. Is there any workaround?

Thanks in advance!

Highlighted

Re: Nifi Issue - writing a JSON file to PutDynamoDb

Explorer

@Shu

Thank you for the response. It is working fine without any errors. However, when I go to the dynamodb table, the entire JSON object from the FlowFile lands under the property set in JSON Document Attribute (in this case, activity) for the PutDynamoDB processor. Attached is a screenshot of the table in dynamodb (3.jpg) 3.jpg

Sample JSON Input:

{

"messageid": "1",

"application": "value 1",

"datetime": "value 2",

"dev": "value 3",

"activity": "value 4"

}

Sample Output in DynamoDB table under a single field called 'activity':

{

"application" : {

"S" : "value 1"

},

"datetime" : {

"S" : "value 2"

},

"dev" : {

"S" : "value 3"

},

"activity" : {

"S" : "value 4"

},

"messageid" : {

"S" : "1"

}

}

I want the JSON contents of the FlowFile to land in DynamoDB as a record with a messageid and 4 fields with their respective values.

I don't know if this is a bug or if I am using it incorrectly. Is there any workaround?

Thanks in advance!

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