vector/common/
expansion.rs

1use regex::Regex;
2use std::{collections::HashMap, sync::LazyLock};
3
4use crate::event::Value;
5
6static RE: LazyLock<Regex> = LazyLock::new(|| Regex::new(r"[^0-9A-Za-z_]").unwrap());
7fn slugify_text(input: &str) -> String {
8    let result = RE.replace_all(input, "_");
9    result.to_lowercase()
10}
11
12/// Expands the given possibly template-able `key_s` and `value_s`, and return the expanded owned pairs
13/// it would also insert the pairs into either `static_pairs` or `dynamic_pairs` depending on the template-ability of `key_s`.
14pub(crate) fn pair_expansion(
15    key_s: &str,
16    value_s: &str,
17    static_pairs: &mut HashMap<String, String>,
18    dynamic_pairs: &mut HashMap<String, String>,
19) -> Result<HashMap<String, String>, serde_json::Error> {
20    let mut expanded_pairs = HashMap::new();
21    if let Some(opening_prefix) = key_s.strip_suffix('*') {
22        let output: serde_json::map::Map<String, serde_json::Value> =
23            serde_json::from_str(value_s)?;
24
25        // key_* -> key_one, key_two, key_three
26        // * -> one, two, three
27        for (k, v) in output {
28            let key = slugify_text(&format!("{opening_prefix}{k}"));
29            let val = Value::from(v).to_string_lossy().into_owned();
30            if val == "<null>" {
31                warn!("Encountered \"null\" value for dynamic pair. key: {}", key);
32                continue;
33            }
34            if let Some(prev) = dynamic_pairs.insert(key.clone(), val.clone()) {
35                warn!(
36                    "Encountered duplicated dynamic pair. \
37                                key: {}, value: {:?}, discarded value: {:?}",
38                    key, val, prev
39                );
40            };
41            expanded_pairs.insert(key, val);
42        }
43    } else {
44        static_pairs.insert(key_s.to_string(), value_s.to_string());
45        expanded_pairs.insert(key_s.to_string(), value_s.to_string());
46    }
47    Ok(expanded_pairs)
48}
vector/common/expansion.rs

vector/common/
expansion.rs
