Metriq - Logging for Solana Smart Contracts

What Is It

Provides functions to produce structured logs in solana smart contracts.

See benchmarks for speed comparisons.

Usage

Add to Cargo.toml:

metriq = "0.1.0"

In your code:

use metriq;
use metriq::FastDisplay;

fn example_function() {
    // Output: some log message^another message^
    metriq::log!("some log message", "another message");
    // Output: key1`value^key2`1^key3`b1^key4`b0^
    metriq::log!(
        metriq::kv("key1", "value"),
        metriq::kv("key2", 1),
        metriq::kv("key3", true),
        metriq::kv("key4", false),
    );
}

metriq::kv accepts a &str key and any value which implements the metriq::FastDisplay trait.

The delimiter between messages in a log! is set to ^ and the delimiter between key value pairs is set to `.

true gets converted to b1. false gets converted to b0.

Benchmarks

Benchmarks compare speed of formatting using format! and metriq::fast_fmt!.

type	format!	metriq::fast_fmt!
Pubkey	2.8627 us	2.7455 us
&str	248.97 ns	225.68 ns
i32	105.85 ns	75.998 ns
ui32	97.742 ns	73.063 ns
key pair (value == &str)	254.15 ns	207.01 ns

Ran on:

MacBook Pro (16-inch, 2019)
2.4 GHz 8-Core Intel Core i9
32 GB 2667 MHz DDR4
30% Battery

Development

To run benchmarks: cargo bench