fetch_and_parse_json

fetch_and_parse_json

async fn fetch_and_parse_json(
    client: &Client,
    api_key: &str,
    access_token: &str,
    symbols: &[&str],
) -> Result<Option<DataFrame>> {
    let url = "https://api.kite.trade/quote";

    let start = Instant::now();

    let params: Vec<(&str, &str)> = symbols.iter().map(|&s| ("i", s)).collect();
    let response: Value = client
        .get(url)
        .header("X-Kite-Version", "3")
        .header(
            "Authorization",
            format!("token {}:{}", api_key, access_token),
        )
        .query(&params)
        .send()
        .await?
        .json()
        .await?;

    println!("JSON fetched in {}ms", start.elapsed().as_millis());

    let json_data = match response.get("data") {
        Some(data) => data,
        None => {
            println!("No 'data' field found in the API response.");
            return Ok(None);
        }
    };

    if json_data.as_object().map_or(true, |obj| obj.is_empty()) {
        println!("No data received from the API.");
        return Ok(None);
    }

    let start = Instant::now();

    let json = serde_json::to_string(&json_data)?;

    println!("JSON parsed in {}ms", start.elapsed().as_millis());

    let start = Instant::now();

    let df = JsonReader::new(Cursor::new(json))
        .with_json_format(JsonFormat::Json)
        .infer_schema_len(Some(NonZeroUsize::new(100).unwrap()))
        .finish()?;

    println!("DataFrame created in {}ms", start.elapsed().as_millis());

    Ok(Some(df))
}