AVRO-3078: Add local-timestamp-millis and local-timestamp-micros logical types to C#

[zcsizmadia]

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  • https://issues.apache.org/jira/browse/AVRO-3078
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[martin-g]

Thank you, @zcsizmadia !

[KalleOlaviNiemitalo]

Is it correct to convert from UTC to local time here? From https://avro.apache.org/docs/1.11.0/spec.html#Local+timestamp+(millisecond+precision), I get the impression that 0 should mean 1 January 1970 00:00:00.000 local time, rather than 1 January 1970 00:00:00.000 UTC converted to local time. I'd really expect the result to have DateTimeKind.Unspecified because it's local time but not necessarily local to the computer in which this library is run.

In the Java implementation, LocalTimestampMillisConversion.fromLong first converts 0 to 1 January 1970 00:00:00.000 UTC and then drops the UTC time zone information, leaving 1 January 1970 00:00:00.000 without a time zone.

avro/lang/java/avro/src/main/java/org/apache/avro/data/TimeConversions.java

Lines 221 to 224 in 4282288

	public LocalDateTime fromLong(Long millisFromEpoch, Schema schema, LogicalType type) {
	Instant instant = timestampMillisConversion.fromLong(millisFromEpoch, schema, type);
	return LocalDateTime.ofInstant(instant, ZoneOffset.UTC);
	}

Related test:

avro/lang/java/avro/src/test/java/org/apache/avro/generic/TestGenericLogicalTypes.java

Lines 325 to 344 in 4e1fefc

	@Test
	public void testReadLocalTimestampMillis() throws IOException {
	LogicalType timestamp = LogicalTypes.localTimestampMillis();
	Schema longSchema = Schema.create(Schema.Type.LONG);
	Schema timestampSchema = timestamp.addToSchema(Schema.create(Schema.Type.LONG));
	LocalDateTime i1 = LocalDateTime.of(1986, 06, 26, 12, 07, 11, 42000000);
	LocalDateTime i2 = LocalDateTime.ofInstant(Instant.ofEpochMilli(0), ZoneOffset.UTC);
	List<LocalDateTime> expected = Arrays.asList(i1, i2);
	Conversion<LocalDateTime> conversion = new TimeConversions.LocalTimestampMillisConversion();
	// use the conversion directly instead of relying on the write side
	Long i1long = conversion.toLong(i1, longSchema, timestamp);
	Long i2long = 0L;
	File test = write(longSchema, i1long, i2long);
	Assert.assertEquals("Should convert long to LocalDateTime", expected,
	read(GENERIC.createDatumReader(timestampSchema), test));
	}