Read/write avro dynamic

readwrite.groovy

    /**
     * Writes the {@link Encounter}s into the specified avro file.
     */
    void write(List<Encounter> encounters, Path output) {

        AvroKeyValue<EncounterKey, Encounter> kvRecord =
                new AvroKeyValue<EncounterKey, Encounter>(new GenericData.Record(schemaEncounterKv))
        DataFileWriter<GenericRecord> fileWriter =
                new DataFileWriter<GenericRecord>(dataModel.createDatumWriter(schemaEncounterKv))

        FSDataOutputStream fsDataOutputStream = fileSystem.create(output, true)
        fileWriter.create(schemaEncounterKv, fsDataOutputStream)

        try {
            encounters.each {
                kvRecord.setKey(new EncounterKey(it.facilityCode.value, it.patNum.value))
                kvRecord.setValue(it)
                fileWriter.append(kvRecord.get())
            }
        } finally {
            fileWriter.close()
        }

    }

    /**
     * Reads the {@link Encounter} instances from an avro file. Not efficient, only for testing.
     */
    Map<EncounterKey, Encounter> read(Path input) {

        SeekableInput fsInput = new FsInput(input, configuration)

        GenericData.Record genericRecord = new GenericData.Record(schemaEncounterKv)
        AvroKeyValue<EncounterKey, Encounter> kvRecord = new AvroKeyValue<EncounterKey, Encounter>(genericRecord)
        DataFileReader<GenericRecord> fileReader = new DataFileReader<GenericRecord>(fsInput, datumReader)

        Map<EncounterKey, Encounter> results = [:]
        try {
            while (fileReader.hasNext()) {
                fileReader.next(genericRecord)
                results[kvRecord.key] = kvRecord.value
            }
        } finally {
            fileReader.close()
        }

        results

    }