lang/rust/avro/examples/test_interop_single_object_encoding.rs

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// to you under the Apache License, Version 2.0 (the
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//
//   http://www.apache.org/licenses/LICENSE-2.0
//
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use apache_avro::{schema::AvroSchema, types::Value};

const RESOURCES_FOLDER: &str = "../../share/test/data/messageV1";

struct InteropMessage;

impl AvroSchema for InteropMessage {
    fn get_schema() -> apache_avro::Schema {
        let schema = std::fs::read_to_string(format!("{}/test_schema.avsc", RESOURCES_FOLDER))
            .expect("File should exist with schema inside");
        apache_avro::Schema::parse_str(schema.as_str())
            .expect("File should exist with schema inside")
    }
}

impl From<InteropMessage> for Value {
    fn from(_: InteropMessage) -> Value {
        Value::Record(vec![
            ("id".into(), 42i64.into()),
            ("name".into(), "Bill".into()),
            (
                "tags".into(),
                Value::Array(
                    vec!["dog_lover", "cat_hater"]
                        .into_iter()
                        .map(|s| s.into())
                        .collect(),
                ),
            ),
        ])
    }
}

fn main() {
    let single_object = std::fs::read(format!("{}/test_message.bin", RESOURCES_FOLDER))
        .expect("File with single object not found or error occurred while reading it.");
    test_write(&single_object);
    test_read(single_object);
}

fn test_write(expected: &[u8]) {
    let mut encoded: Vec<u8> = Vec::new();
    apache_avro::SpecificSingleObjectWriter::<InteropMessage>::with_capacity(1024)
        .expect("Resolving failed")
        .write_value(InteropMessage, &mut encoded)
        .expect("Encoding failed");
    assert_eq!(expected, &encoded)
}

fn test_read(encoded: Vec<u8>) {
    let mut encoded = &encoded[..];
    let read_message = apache_avro::GenericSingleObjectReader::new(InteropMessage::get_schema())
        .expect("Resolving failed")
        .read_value(&mut encoded)
        .expect("Decoding failed");
    let expected_value: Value = InteropMessage.into();
    assert_eq!(expected_value, read_message)
}