Crate solana_program_log 

Lightweight log utility for Solana programs.

Logging is the main mechanism for getting debugging information out of running Solana programs, and there are several functions available for doing so efficiently, depending on the type of data being logged.

This crate provides a Logger struct and a collection of helper functions that can be used to efficiently log messages in a Solana program.

The Logger struct is a wrapper around a fixed-size buffer. Types that implement the Log trait can be appended to this buffer. The struct is generic over the buffer size, which should be chosen based on the expected size of the log messages. When the buffer becomes full, the log message is truncated, indicated by an @ character at the end of the message.

Example

Creating a Logger with a buffer size of 100 bytes, and appending a string and an u64 value:

use solana_program_log::Logger;

let mut logger = Logger::<100>::default();
logger.append("balance=");
logger.append(1_000_000_000);
logger.log();

// Clear the logger buffer.
logger.clear();

logger.append(&["Hello ", "world!"]);
logger.log();

It also support adding precision to numeric types:

use solana_program_log::{Argument, Logger};

let mut logger = Logger::<100>::default();

let lamports = 1_000_000_000u64;

logger.append("balance (SOL)=");
logger.append_with_args(lamports, &[Argument::Precision(9)]);
logger.log();

Re-exports

pub use logger::Argument;

pub use logger::Logger;

Modules

logger

Macros

logmacro

Companion log! macro for solana-program-log.

Functions

log

Print a string to the log.

log_64

Print 64-bit values represented as hexadecimal to the log.

log_compute_units

Print the remaining compute units available to the program.

log_data

Print some slices as base64.

Attribute Macros

log_cu_usagemacro

Attribute macro for instrumenting functions with compute unit logging.