Leon Mika
917663fac0
- Most aspects of scans and queries can now be represented using the expression language - All constructs of the expression language can be used to evaluate items
40 lines
1 KiB
Go
40 lines
1 KiB
Go
package queryexpr
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import (
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"context"
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"github.com/aws/aws-sdk-go-v2/service/dynamodb/types"
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"github.com/pkg/errors"
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"strconv"
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)
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type nativeFunc func(ctx context.Context, args []types.AttributeValue) (types.AttributeValue, error)
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var nativeFuncs = map[string]nativeFunc{
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"size": func(ctx context.Context, args []types.AttributeValue) (types.AttributeValue, error) {
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if len(args) != 1 {
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return nil, InvalidArgumentNumberError{Name: "size", Expected: 1, Actual: len(args)}
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}
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var l int
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switch t := args[0].(type) {
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case *types.AttributeValueMemberB:
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l = len(t.Value)
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case *types.AttributeValueMemberS:
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l = len(t.Value)
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case *types.AttributeValueMemberL:
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l = len(t.Value)
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case *types.AttributeValueMemberM:
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l = len(t.Value)
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case *types.AttributeValueMemberSS:
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l = len(t.Value)
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case *types.AttributeValueMemberNS:
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l = len(t.Value)
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case *types.AttributeValueMemberBS:
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l = len(t.Value)
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default:
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return nil, errors.New("cannot take size of arg")
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}
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return &types.AttributeValueMemberN{Value: strconv.Itoa(l)}, nil
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},
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}
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