Function extract_session_short

atomic-agent/src/identity.rs:339–364

Extract a short identifier from the session ID for the `+tag` suffix. Takes the first 4 hex characters from the session ID. If the session ID has a date prefix (e.g., `2026-01-15-abc123de-...`), skips the date part and uses the first 4 chars of the UUID portion. # Examples ```rust use atomic_agent::identity::extract_session_short; assert_eq!(extract_session_short("60f5cbd2-aa23-40ee-9085-4375d

(session_id: &str)

/// assert_eq!(extract_session_short("ab"), "ab");
/// ```
pub fn extract_session_short(session_id: &str) -> String {
    // Check for date prefix pattern: YYYY-MM-DD-<rest>
    let id_part = if session_id.len() > 11
        && session_id.as_bytes()[4] == b'-'
        && session_id.as_bytes()[7] == b'-'
        && session_id.as_bytes()[10] == b'-'
    {
        // Skip the "YYYY-MM-DD-" prefix (11 chars)
        &session_id[11..]
    } else {
        session_id
    };

    // Take the first 4 alphanumeric characters
    let short: String = id_part
        .chars()
        .filter(|c| c.is_ascii_alphanumeric())
        .take(4)
        .collect();

    if short.is_empty() {
        "0000".to_string()
    } else {
        short
    }
}

/// Normalize the agent name for use in the `+tag`.
///