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Utilities Module

Path: src/util/

Helper functions for formatting values and parsing timestamps.

Files

FilePurpose
format.rsHuman-readable formatting for durations, bytes, strings, and SQL plans
time.rsSpark timestamp parsing and duration calculation

format.rs — Formatting

FunctionSignatureDescription
format_duration_ms(ms: i64) -> StringFormats milliseconds as human-readable duration (e.g., 1h 23m 45s, 500ms, 2.3s)
format_bytes(bytes: i64) -> StringFormats byte counts with appropriate unit (e.g., 1.5 GB, 256 MB, 1.2 KB)
format_bytes_or_dash(bytes: i64) -> StringLike format_bytes, but returns "-" if bytes is zero
format_records(records: i64) -> StringFormats record counts with K/M/B suffixes
percentile(sorted: &[f64], p: f64) -> f64Computes percentile from a sorted slice
truncate(s: &str, max: usize) -> StringTruncates a string to max characters, appending ... if truncated
sanitize_for_span(s: &str) -> StringReplaces embedded newlines, carriage returns, and tabs with spaces. Ratatui’s Line/Span types expect no embedded newlines — they corrupt the differential renderer’s cursor position tracking
clean_stage_name(name: &str) -> StringRemoves Spark Connect prefixes and UUID suffixes from stage names for cleaner display
parse_plan_top_operations(plan: &str, limit: usize) -> Vec<String>Extracts the top N operations from a Spark SQL physical plan

Examples

#![allow(unused)]
fn main() {
format_duration_ms(3_723_000) // "1h 2m 3s"
format_duration_ms(500)        // "500ms"
format_duration_ms(2_300)      // "2.3s"

format_bytes(1_610_612_736)    // "1.5 GB"
format_bytes(1_048_576)        // "1.0 MB"

truncate("hello world", 5)     // "hello..."

clean_stage_name("spark-connect-UUID:stage_name") // "stage_name"
}

time.rs — Time Utilities

FunctionSignatureDescription
parse_spark_timestamp(s: &str) -> Option<DateTime<Utc>>Parses Spark timestamps in multiple formats: RFC3339, naive datetime, and GMT-suffix
duration_between(start: Option<&str>, end: Option<&str>) -> Option<i64>Computes duration in milliseconds between two optional timestamp strings

Supported Timestamp Formats

  • RFC3339: 2024-01-15T10:30:00.000Z
  • Naive: 2024-01-15T10:30:00.000
  • GMT suffix: 2024-01-15T10:30:00.000GMT

Examples

#![allow(unused)]
fn main() {
parse_spark_timestamp("2024-01-15T10:30:00.000GMT") // Some(DateTime<Utc>)

duration_between(
    Some("2024-01-15T10:30:00.000GMT"),
    Some("2024-01-15T10:31:00.000GMT"),
) // Some(60_000)

duration_between(Some("..."), None) // None
}