AWS Firehose DynamicPartitioningConfiguration/Prefix simply won't work - amazon-web-services

Question

I've been slamming my head against the wall for the past 2 days trying to get dynamic partitioning to work in the delivery stream I'm creating using a serverless application model template. I've tried multiple configurations, but it seems as soon as I fill in a prefix, enable dynamic partitioning and add a metadata extraction processor to get myself a field I can use as the prefix my stack stops working, I can generate alerts in aws and see the logs from the lambda processor I also added, but no files reach the bucket, I also can't seem to configure cloudwatch logs for the stream as well, since I've tried creating them through the script and manually and neither at least have logs pertaining to any error....
I'll leave my script here, hopefully I'm doing something wrong:
{
"AWSTemplateFormatVersion": "2010-09-09",
"Transform": "AWS::Serverless-2016-10-31",
"Description": "An AWS Serverless Application.",
"Parameters": {
"BucketArn": {
"Type": "String"
}
},
"Resources": {
"DeliveryPolicy": {
"Type": "AWS::IAM::Policy",
"Properties": {
"PolicyName": "K-POLICY",
"Roles": [
{
"Ref": "DeliveryRole"
}
],
"PolicyDocument": {
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Action": [
"s3:*"
],
"Resource": [
{
"Ref": "BucketArn"
}
]
},
{
"Effect": "Allow",
"Action": [
"lambda:InvokeFunction",
"lambda:GetFunctionConfiguration"
],
"Resource": [
{
"Fn::GetAtt": [
"Processor",
"Arn"
]
}
]
}
]
}
}
},
"DeliveryRole": {
"Type": "AWS::IAM::Role",
"Properties": {
"AssumeRolePolicyDocument": {
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Principal": {
"Service": [
"firehose.amazonaws.com"
]
},
"Action": [
"sts:AssumeRole"
]
}
]
}
}
},
"DeliveryStream": {
"Type": "AWS::KinesisFirehose::DeliveryStream",
"Properties": {
"DeliveryStreamName": "K-STREAM",
"DeliveryStreamType": "DirectPut",
"ExtendedS3DestinationConfiguration": {
"BucketARN": {
"Ref": "BucketArn"
},
"Prefix": "!{partitionKeyFromQuery:symb}",
"ErrorOutputPrefix": "errors/!{firehose:random-string}/!{firehose:error-output-type}/!{timestamp:yyyy/MM/dd}",
"RoleARN": {
"Fn::GetAtt": [
"DeliveryRole",
"Arn"
]
},
"DynamicPartitioningConfiguration": {
"Enabled": true
},
"ProcessingConfiguration": {
"Enabled": true,
"Processors": [
{
"Type": "MetadataExtraction",
"Parameters": [
{
"ParameterName": "MetadataExtractionQuery",
"ParameterValue": "{symb: .TICKER_SYMBOL}"
},
{
"ParameterName": "JsonParsingEngine",
"ParameterValue": "JQ-1.6"
}
]
},
{
"Type": "Lambda",
"Parameters": [
{
"ParameterName": "LambdaArn",
"ParameterValue": {
"Fn::GetAtt": [
"Processor",
"Arn"
]
}
}
]
}
]
}
}
}
},
"Processor": {
"Type": "AWS::Serverless::Function",
"Properties": {
"Handler": "K-PROCESSOR::KRATOS_PROCESSOR.Functions::FunctionHandler",
"FunctionName": "K-PROCESSOR",
"Runtime": "dotnetcore3.1",
"CodeUri": "./staging/app/3cs-int-k",
"MemorySize": 256,
"Timeout": 60,
"Role": null,
"Policies": [
"AWSLambdaBasicExecutionRole"
]
}
}
}
}