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DISC003: Invalid discriminator pattern syntax

FieldValue
CodeDISC003
SeverityError

Message​

Entity '{0}' has invalid discriminator pattern '{1}': {2}. Patterns should use '*' as a wildcard (e.g., 'USER#*', '*#USER', '*USER*').

Description​

Discriminator patterns must use valid syntax with * as a wildcard character. The wildcard matches zero or more characters in the discriminator attribute value. Supported patterns include prefix match (USER#*), suffix match (*#USER), and contains match (*USER*).

Complex patterns with multiple wildcards in non-standard positions may not be supported. The source generator validates pattern syntax during compilation and emits this error when it cannot parse the pattern into a usable matching strategy.

Example​

The following code triggers this diagnostic:

[DynamoDbTable("shared-table", IsDefault = true)]
public partial class Order
{
    [PartitionKey]
    [DynamoDbAttribute("pk")]
    public string Pk { get; set; } = string.Empty;

    [GsiPartitionKey("gsi1",
        DiscriminatorProperty = "entityType",
        DiscriminatorPattern = "[ORDER]")]
    [DynamoDbAttribute("gsi1pk")]
    public string Gsi1Pk { get; set; } = string.Empty;
}

Fix​

The corrected version:

[DynamoDbTable("shared-table", IsDefault = true)]
public partial class Order
{
    [PartitionKey]
    [DynamoDbAttribute("pk")]
    public string Pk { get; set; } = string.Empty;

    [GsiPartitionKey("gsi1",
        DiscriminatorProperty = "entityType",
        DiscriminatorPattern = "ORDER*")]
    [DynamoDbAttribute("gsi1pk")]
    public string Gsi1Pk { get; set; } = string.Empty;
}