Add JSON and BSON logical type test files

[nssalian]

• closesAdd examples for JSON and BSON logical types #101

Adds two fixtures for the JSON and BSON logical types along with the README update.

• data/json.parquet (4 rows): {"a":1}, {"a":1,"b":null}, [1,null,3], and a NULL row.
• data/bson.parquet (3 rows): BSON {"a":1}, {"a":1,"b":null}, and a NULL row.
• data/README.md has a "JSON and BSON logical types"

Both are a single optional BYTE_ARRAY column and were generated by parquet-mr 1.18.0-SNAPSHOT
Verified readable by both parquet-java's reader and pyarrow, and the BSON payloads decode with a BSON library. data/README.md has a "JSON and BSON logical types" section with the generator programs and the read-back.

[nssalian]

@emkornfield@alamb PTAL

[alamb]

Thanks @nssalian -- I double checked the contents of these files and they make sense to me

[alamb]

I verified the contents of this with datafusion-cli:

$ datafusion-cli -c "SELECT * from 'data/json.parquet'"
DataFusion CLI v54.1.0+------------------+
| json_field |
+------------------+
| {"a":1} |
| {"a":1,"b":null} |
| [1,null,3] |
| NULL |
+------------------+4 row(s) fetched.
Elapsed 0.039 seconds.

[alamb]

Metadata is good too

andrewlamb@Andrews-MacBook-Pro-3:~/Software/parquet-testing$ ~/Software/arrow-rs/target/release/parquet-schema data/json.parquet
Metadata for file: data/json.parquet
version: 1
num of rows: 4
created by: parquet-mr version 1.18.0-SNAPSHOT (build 1a9e455655604acf09cdd45b4e2958661d38281c)
metadata:
writer.model.name: example
message json_fixture {
OPTIONAL BYTE_ARRAY json_field (JSON);
}

[alamb]

Contents look good:

datafusion-cli -c "SELECT * from 'data/bson.parquet'"
DataFusion CLI v54.1.0+--------------------------------+
| bson_field |
+--------------------------------+
| 0c0000001061000100000000 |
| 0f000000106100010000000a620000 |
| NULL |
+--------------------------------+3 row(s) fetched.

I decoded into bson and it matches the contents:

andrewlamb@Andrews-MacBook-Pro-3:~/Software/parquet-testing$ uvrun--withpymongo--withpyarrowpython3-c "
importbson, pyarrow.parquetaspqt=pq.read_table('data/bson.parquet')
forvint.column('bson_field'):
print('NULL'ifnotv.is_validelsebson.decode(v.as_py()))
"
{'a': 1}{'a': 1, 'b': None}NULL

As does metadata

andrewlamb@Andrews-MacBook-Pro-3:~/Software/parquet-testing$ ~/Software/arrow-rs/target/release/parquet-schema data/bson.parquet
Metadata for file: data/bson.parquet
version: 1
num of rows: 3
created by: parquet-mr version 1.18.0-SNAPSHOT (build 1a9e455655604acf09cdd45b4e2958661d38281c)
metadata:
writer.model.name: example
message bson_fixture {
OPTIONAL BYTE_ARRAY bson_field (BSON);
}

[nssalian]

Thank you for the review and testing it out @alamb

[alamb]

Thanks again @nssalian