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47 lines
1.5 KiB
Go
47 lines
1.5 KiB
Go
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package decoders
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import (
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"fmt"
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"github.com/wader/fq/format/avro/schema"
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"github.com/wader/fq/pkg/decode"
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)
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func decodeRecordFn(schema schema.SimplifiedSchema) (func(string, *decode.D), error) {
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if len(schema.Fields) == 0 {
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return nil, fmt.Errorf("record must have fields")
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}
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var fieldNames []string
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var fieldDecoders []func(string, *decode.D)
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for _, f := range schema.Fields {
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fieldNames = append(fieldNames, f.Name)
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fc, err := DecodeFnForSchema(f.Type)
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if err != nil {
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return nil, fmt.Errorf("failed parsing record field %s: %v", f.Name, err)
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}
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fieldDecoders = append(fieldDecoders, fc)
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}
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//A record is encoded by encoding the values of its fields in the order that they are declared. In other words, a
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//record is encoded as just the concatenation of the encodings of its fields. Field values are encoded per their
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//schema. For example, the record schema
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// { "type": "record",
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// "name": "test",
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// "fields" : [ {"name": "a", "type": "long"},
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// {"name": "b", "type": "string"} ]
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// }
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//
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//An instance of this record whose a field has value 27 (encoded as hex 36) and whose b field has value "foo"
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//(encoded as hex bytes 06 66 6f 6f), would be encoded simply as the concatenation of these, namely
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//the hex byte sequence:
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//36 06 66 6f 6f
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return func(name string, d *decode.D) {
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d.FieldStruct(name, func(d *decode.D) {
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for i, f := range fieldNames {
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fieldDecoders[i](f, d)
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}
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})
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}, nil
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}
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