Crate libflatterer
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libflatterer - Library to make JSON flatterer.
Mainly used for flatterer, which is a python library/cli using bindings to this library. Read flatterer documentation to give high level overview of how the flattening works. Nonetheless can be used as a standalone Rust library.
High level usage, use flatten function, supply a BufReader, an output directory and the Options struct (generated with the builder pattern):
use tempfile::TempDir;
use std::fs::File;
use libflatterer::{flatten, Options};
use std::io::BufReader;
let tmp_dir = TempDir::new().unwrap();
let output_dir = tmp_dir.path().join("output");
let options = Options::builder().xlsx(true).sqlite(true).parquet(true).table_prefix("prefix_".into()).build();
flatten(
Box::new(BufReader::new(File::open("fixtures/basic.json").unwrap())), // reader
output_dir.to_string_lossy().into(), // output directory
options, // options
).unwrap();
Lower level usage, use the FlatFiles struct directly and supply options.
use tempfile::TempDir;
use std::fs::File;
use libflatterer::{FlatFiles, Options};
use std::io::BufReader;
use serde_json::json;
let myjson = json!({
"a": "a",
"c": ["a", "b", "c"],
"d": {"da": "da", "db": "2005-01-01"},
"e": [{"ea": "ee", "eb": "eb2"},
{"ea": "ff", "eb": "eb2"}],
});
let tmp_dir = TempDir::new().unwrap();
let output_dir = tmp_dir.path().join("output");
let options = Options::builder().xlsx(true).sqlite(true).parquet(true).table_prefix("prefix_".into()).build();
// Create FlatFiles struct
let mut flat_files = FlatFiles::new(
output_dir.to_string_lossy().into(), // output directory
options
).unwrap();
// process JSON to memory
flat_files.process_value(myjson.clone(), vec![]);
// write processed JSON to disk. Do not need to do this for every processed value, but it is recommended.
flat_files.create_rows();
// copy the above two lines for each JSON object e.g..
flat_files.process_value(myjson.clone(), vec![]);
flat_files.create_rows();
// ouput the selected formats
flat_files.write_files();