datafusion-sqlparse/examples/cli.rs
2019-06-02 13:48:14 +03:00

57 lines
1.8 KiB
Rust

#![warn(clippy::all)]
use simple_logger;
///! A small command-line app to run the parser.
/// Run with `cargo run --example cli`
use std::fs;
use sqlparser::dialect::*;
use sqlparser::sqlparser::Parser;
fn main() {
simple_logger::init().unwrap();
let filename = std::env::args().nth(1).expect(
"No arguments provided!\n\n\
Usage: cargo run --example cli FILENAME.sql [--dialectname]",
);
let dialect: Box<dyn Dialect> = match std::env::args().nth(2).unwrap_or_default().as_ref() {
"--ansi" => Box::new(AnsiSqlDialect {}),
"--postgres" => Box::new(PostgreSqlDialect {}),
"--ms" => Box::new(MsSqlDialect {}),
"--generic" | "" => Box::new(GenericSqlDialect {}),
s => panic!("Unexpected parameter: {}", s),
};
println!("Parsing from file '{}' using {:?}", &filename, dialect);
let contents = fs::read_to_string(&filename)
.unwrap_or_else(|_| panic!("Unable to read the file {}", &filename));
let without_bom = if contents.chars().nth(0).unwrap() as u64 != 0xfeff {
contents.as_str()
} else {
let mut chars = contents.chars();
chars.next();
chars.as_str()
};
let parse_result = Parser::parse_sql(&*dialect, without_bom.to_owned());
match parse_result {
Ok(statements) => {
println!(
"Round-trip:\n'{}'",
statements
.iter()
.map(std::string::ToString::to_string)
.collect::<Vec<_>>()
.join("\n")
);
println!("Parse results:\n{:#?}", statements);
std::process::exit(0);
}
Err(e) => {
println!("Error during parsing: {:?}", e);
std::process::exit(1);
}
}
}