Unable to Scan with Multiple Conditions

[jbtdevgit]

Describe the bug

Hi,

I was unable to scan objects with multiple conditions using ScanAsync below is the code snippet:

if(DynamoDBContext != null)
{
     List<ScanCondition> scanConditions = new List<ScanCondition>
     {
           new ScanCondition("SortKey", ScanOperator.Equal, "sk1"),
           new ScanCondition("TestBool", ScanOperator.Equal, new DynamoDBBool(true))
      };
     return await DynamoDBContext.ScanAsync<T>(scanConditions).GetRemainingAsync();
}

And below I have these in my table:

Below is the result of the debug:

Removing one of the conditions will give me results:

Expected Behavior

Return based on the scan conditions

Current Behavior

Did not return

Reproduction Steps

Add multiple conditions on scan conditions list

Possible Solution

No response

Additional Information/Context

No response

AWS .NET SDK and/or Package version used

AWSSDK.AmazonDynamoDBv2 3.7.103.21

Targeted .NET Platform

.NET 7

Operating System and version

Windows 10

[ashishdhingra]

Hi @jbtamaresgit,

Good morning.

Thanks for reporting the issue.

Unfortunately, I'm unable to reproduce the issue. For Object Persistence model, you would need to use convertor to convert between bool and DynamoDBBool types, and also need to set DynamoDBContextConfig.Conversion for DynamoDBContext to DynamoDBEntryConversion.V2. I suspect there might be an issue with your convertor where it might only be handling bool data, not if the user passes DynamoDBBool in ScanCondition (you might try using true value directly in your code to see if it works).

For the example table schema shared by you, the below code works fine (2 results are returned; where I created 3 items with one of them having TestBool value as false):

using System;
using System.Collections.Generic;
using Amazon.DynamoDBv2;
using Amazon.DynamoDBv2.DataModel;
using Amazon.DynamoDBv2.DocumentModel;
using Amazon.Runtime;

using (AmazonDynamoDBClient client = new AmazonDynamoDBClient())
{
    DynamoDBContext context = new DynamoDBContext(client, new DynamoDBContextConfig() { Conversion = DynamoDBEntryConversion.V2 });

    if (context != null)
    {
        List<ScanCondition> scanConditions = new List<ScanCondition>
        {
           new ScanCondition("SortKey", ScanOperator.Equal, "sk1"),
           new ScanCondition("TestBool", ScanOperator.Equal, new DynamoDBBool(true))
        };
        var scanResponse = await context.ScanAsync<TestTable>(scanConditions).GetRemainingAsync();
    }
}

[DynamoDBTable("TestTable")]
public class TestTable
{
    [DynamoDBHashKey]
    public string Id { get; set; }

    [DynamoDBRangeKey]
    public string SortKey { get; set; }

    [DynamoDBProperty("TestBool", typeof(DynamoDBNativeBooleanConverter))]
    public bool TestBool { get; set; }
}

public class DynamoDBNativeBooleanConverter : IPropertyConverter
{
    public DynamoDBEntry ToEntry(object value)
    {
        DynamoDBEntry entry = DynamoDBNull.Null;

        if (value != null)
        {
            if (value is DynamoDBBool)
            {
                entry = (DynamoDBBool) value;
            }
            else
            {
                entry = new DynamoDBBool(bool.TryParse(value?.ToString(), out var val) && val);
            }
        }

        return entry;
    }

    public object FromEntry(DynamoDBEntry entry)
    {
        return entry.AsDynamoDBBool().Value;
    }
}

Thanks,
Ashish

[jbtdevgit]

Hi @ashishdhingra ,
I do not have the conversion set DynamoDBContextConfig.Conversion for DynamoDbContext but I do have the property converter

public class DynamoDBNativeBooleanConverter : IPropertyConverter
{
        public DynamoDBEntry ToEntry(object value) => new DynamoDBBool(bool.TryParse(value?.ToString(), out var val) && val);
        public object FromEntry(DynamoDBEntry entry) => entry.AsDynamoDBBool().Value;
}

And that should not be a problem since I can comment out the SortKey Condition and leave the TestBool and it will return those with TestBool as True but never did when adding both of the ScanCondition.

I suspect there might be an issue with your convertor where it might only be handling bool data, not if the user passes DynamoDBBool in ScanCondition (you might try using true value directly in your code to see if it works).

I also did try this, but it did not work as well.

Does the conversion for the DynamoDbContext needed to be added in order for multiple ScanConditions to work?
And by the way, what package version are you using? Are you you using the same package as I am, or is it a newer version?

---

Update:
Updated the package to v3.7.105
Added DynamoDBEntryConversion.V2
And it is still not working.

Code snippet for DynamoDbContext

DynamoDBContext = new DynamoDBContext(DynamoDBClient, new DynamoDBContextConfig()
{
    Conversion = DynamoDBEntryConversion.V2
});

Fetching of items is still the same

if(DynamoDBContext != null)
{
     List<ScanCondition> scanConditions = new List<ScanCondition>
     {
           new ScanCondition("SortKey", ScanOperator.Equal, "sk1"),
           new ScanCondition("TestBool", ScanOperator.Equal, new DynamoDBBool(true))
      };
     return await DynamoDBContext.ScanAsync<T>(scanConditions).GetRemainingAsync();
}

[ashishdhingra]

Hi @ashishdhingra ,
I do not have the conversion set DynamoDBContextConfig.Conversion for DynamoDbContext but I do have the property converter

public class DynamoDBNativeBooleanConverter : IPropertyConverter
{
public DynamoDBEntry ToEntry(object value) => new DynamoDBBool(bool.TryParse(value?.ToString(), out var val) && val);
public object FromEntry(DynamoDBEntry entry) => entry.AsDynamoDBBool().Value;
}
And that should not be a problem since I can comment out the SortKey Condition and leave the TestBool and it will return those with TestBool as True but never did when adding both of the ScanCondition.

@jbtamaresgit Good morning. I was also using the same converter as you, but since you are using ScanCondition("TestBool", ScanOperator.Equal, new DynamoDBBool(true)), the property converter's ToEntry will fail since it is trying to use bool.TryParse() on DynamoDBBool object. Please modify your converter to the logic shared in #2987 (comment). Also make sure to decorate TestBool property with [DynamoDBProperty("TestBool", typeof(DynamoDBNativeBooleanConverter))] attribute. The code shared in #2987 (comment) works perfectly fine at my end.

Thanks,
Ashish

[jbtdevgit]

Hi @ashishdhingra ,
I reworked our tables so I am using QueryAsync to query objects with a single ScanCondition and it works great, so I guess I am not going to dabble around the ScanAsync. Thanks for your help.

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