use async_trait::async_trait;
use file_type::FileType;
use polars::io::SerReader;
use polars::prelude::{IntoLazy, JsonReader};
use polars_sql::SQLContext;
use rsql_driver::Error::{ConversionError, IoError};
use rsql_driver::{Result, UrlExtension};
use rsql_driver_polars::Connection;
use std::collections::HashMap;
use std::io::Cursor;
use std::num::NonZeroUsize;
use url::Url;
#[derive(Debug)]
pub struct Driver;
#[async_trait]
impl rsql_driver::Driver for Driver {
fn identifier(&self) -> &'static str {
"yaml"
}
async fn connect(&self, url: &str) -> Result<Box<dyn rsql_driver::Connection>> {
let parsed_url = Url::parse(url)?;
let query_parameters: HashMap<String, String> =
parsed_url.query_pairs().into_owned().collect();
let file_name = parsed_url.to_file()?.to_string_lossy().to_string();
let json = {
#[cfg(target_family = "wasm")]
let yaml = std::fs::read_to_string(&file_name)?;
#[cfg(not(target_family = "wasm"))]
let yaml = tokio::fs::read_to_string(&file_name).await?;
let yaml_value: serde_json::Value =
serde_saphyr::from_str(&yaml).map_err(|error| IoError(error.to_string()))?;
serde_json::to_string(&yaml_value).map_err(|error| IoError(error.to_string()))?
};
let ignore_errors = query_parameters
.get("ignore_errors")
.is_some_and(|value| value == "true");
let infer_schema_length = match query_parameters.get("infer_schema_length") {
Some(infer_schema_length) => {
let length = infer_schema_length
.parse::<usize>()
.map_err(|error| ConversionError(error.to_string()))?;
if length == 0 {
None
} else {
NonZeroUsize::new(length)
}
}
None => NonZeroUsize::new(100),
};
let cursor = Cursor::new(json.as_bytes());
let data_frame = JsonReader::new(cursor)
.infer_schema_len(infer_schema_length)
.set_rechunk(true)
.with_ignore_errors(ignore_errors)
.finish()
.map_err(|error| IoError(error.to_string()))?;
let table_name = rsql_driver_polars::get_table_name(file_name)?;
let context = SQLContext::new();
context.register(table_name.as_str(), data_frame.lazy());
let connection = Connection::new(url, context).await?;
Ok(Box::new(connection))
}
fn supports_file_type(&self, file_type: &FileType) -> bool {
let extensions = file_type.extensions();
let media_types = file_type.media_types();
media_types.contains(&"text/x-yaml")
|| media_types.contains(&"application/yaml")
|| extensions.contains(&"yml")
|| extensions.contains(&"yaml")
}
}