DYNDB036: Invalid computed key format

Field	Value
Code	DYNDB036
Severity	Warning

Message

Computed property '{0}' has format '{1}' that may produce invalid keys: {2}

Description

Computed key formats should produce valid DynamoDB key values. Formats that can produce empty strings, excessively long keys, or keys with problematic characters are flagged as potentially invalid.

Example

The following code triggers this diagnostic:

[DynamoDbTable("Events")]
public partial class Event
{
    [PartitionKey]
    [DynamoDbAttribute("pk")]
    [Computed("Year", "Month", Separator = "#", Format = "{0}###{1}")]
    public string Pk { get; set; } = string.Empty;

    [Extracted("Pk", 0)]
    public int Year { get; set; }

    [Extracted("Pk", 1)]
    public int Month { get; set; }
}

Fix

The corrected version:

[DynamoDbTable("Events")]
public partial class Event
{
    [PartitionKey]
    [DynamoDbAttribute("pk")]
    [Computed("Year", "Month", Separator = "#")]
    public string Pk { get; set; } = string.Empty;

    [Extracted("Pk", 0)]
    public int Year { get; set; }

    [Extracted("Pk", 1)]
    public int Month { get; set; }
}