finance-query 2.8.0

A Rust library for querying financial data
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130

//! Yahoo Finance exchanges scraper.
//!
//! Scrapes the Yahoo Finance help page to get a list of supported exchanges
//! with their suffixes and data providers.

use crate::error::{FinanceError, Result};
use crate::models::market::exchanges::Exchange;
use crate::scrapers::html;
use tracing::info;

const EXCHANGES_URL: &str = "https://help.yahoo.com/kb/finance-for-web/SLN2310.html";

/// Scrape the Yahoo Finance help page for supported exchanges.
///
/// Returns a list of exchanges with their suffixes and data delay information.
pub async fn scrape_exchanges() -> Result<Vec<Exchange>> {
    info!("Fetching exchanges from Yahoo Finance help page");

    let client = reqwest::Client::builder()
        .user_agent("Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36")
        .build()?;

    let response = client.get(EXCHANGES_URL).send().await?;

    if !response.status().is_success() {
        return Err(FinanceError::ServerError {
            status: response.status().as_u16(),
            context: "Failed to fetch exchanges page".to_string(),
        });
    }

    let html = response.text().await?;

    parse_exchanges_html(&html)
}

/// Parse the exchanges HTML table.
fn parse_exchanges_html(document: &str) -> Result<Vec<Exchange>> {
    let table = html::find_first(document, "table").ok_or_else(|| {
        FinanceError::ResponseStructureError {
            field: "table".to_string(),
            context: "No table found in exchanges page".to_string(),
        }
    })?;

    let mut exchanges = Vec::new();

    for row in html::find_all(table.inner, "tr") {
        let cells = html::find_all(row.inner, "td");

        // Skip header rows (they use <th> not <td>)
        if cells.len() != 5 {
            continue;
        }

        let country = cells[0].text().trim().to_string();
        let market = cells[1].text().trim().to_string();
        let suffix = cells[2].text().trim().to_string();
        let delay = cells[3].text().trim().to_string();
        let data_provider = cells[4].text().trim().to_string();

        exchanges.push(Exchange {
            country,
            market,
            suffix,
            delay,
            data_provider,
        });
    }

    if exchanges.is_empty() {
        return Err(FinanceError::ResponseStructureError {
            field: "exchanges".to_string(),
            context: "No exchanges found in table".to_string(),
        });
    }

    info!("Found {} exchanges", exchanges.len());
    Ok(exchanges)
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn parses_exchanges_table_offline() {
        let html = r#"
            <html><body>
            <table>
              <tr><th>Country</th><th>Market</th><th>Suffix</th><th>Delay</th><th>Provider</th></tr>
              <tr><td>United States of America</td><td>NASDAQ</td><td></td><td>Real-time</td><td>Nasdaq</td></tr>
              <tr><td>Japan</td><td>Tokyo Stock Exchange</td><td>.T</td><td>20 min</td><td>Tokyo</td></tr>
            </table>
            </body></html>
        "#;

        let exchanges = parse_exchanges_html(html).unwrap();
        assert_eq!(exchanges.len(), 2);
        assert_eq!(exchanges[0].country, "United States of America");
        assert_eq!(exchanges[1].suffix, ".T");
    }

    #[test]
    fn errors_when_no_table_present() {
        let result = parse_exchanges_html("<html><body>no table here</body></html>");
        assert!(result.is_err());
    }

    #[tokio::test]
    #[ignore] // Requires network access
    async fn test_scrape_exchanges() {
        let result = scrape_exchanges().await;
        assert!(result.is_ok(), "Failed: {:?}", result.err());

        let exchanges = result.unwrap();
        assert!(!exchanges.is_empty());

        // Check for some known exchanges
        let has_nyse = exchanges
            .iter()
            .any(|e| e.market.contains("Nasdaq") && e.country == "United States of America");
        assert!(has_nyse, "Should have US Nasdaq");

        let has_tokyo = exchanges
            .iter()
            .any(|e| e.market.contains("Tokyo") && e.suffix == ".T");
        assert!(has_tokyo, "Should have Tokyo Stock Exchange with .T suffix");
    }
}