Module current_tx 

Current Transaction Retrieval Module

This module provides utilities for retrieving typed fields from the current XRPL transaction within the context of XRPL Programmability. It offers a safe, type-safe interface over the low-level host functions for accessing transaction data, such as from an EscrowFinish transaction.

Overview

When processing XRPL transactions in a permissionless programmability environment, you often need to extract specific fields like account IDs, hashes, public keys, and other data. This module provides convenient wrapper functions that handle the low-level buffer management and error handling required to safely retrieve these fields.

Field Types Supported

• AccountID: 20-byte account identifiers
• u32: 32-bit unsigned integers
• Hash256: 256-bit cryptographic hashes
• PublicKey: 33-byte public keys
• Blob: Variable-length binary data

Optional vs Required Fields

The module provides both optional and required variants for field retrieval:

• Required variants (e.g., get_u32_field): Return an error if the field is missing
• Optional variants (e.g., get_optional_u32_field): Return None if the field is missing

Error Handling

All functions return Result<T> or Result<Option<T>> types that encapsulate the custom error handling required for the XRPL Programmability environment.

Safety Considerations

• All functions use fixed-size buffers appropriate for their data types
• Buffer sizes are validated against expected field sizes
• Unsafe operations are contained within the low-level host function calls
• Memory safety is ensured through proper buffer management
• Field codes are validated by the underlying host functions

Performance Notes

• All functions are marked #[inline] to minimize call overhead
• Buffer allocations are stack-based and have minimal cost
• Host function calls are the primary performance bottleneck

Example

Get sender Account and optional flags:

use xrpl_wasm_stdlib::core::current_tx::escrow_finish::EscrowFinish;
use xrpl_wasm_stdlib::core::current_tx::traits::TransactionCommonFields;
let tx = EscrowFinish;
let account = tx.get_account().unwrap_or_panic();
let _flags = tx.get_flags().unwrap_or_panic();

Modules

escrow_finish

EscrowFinish

traits

Transaction Field Access Traits

Traits

CurrentTxFieldGetter

Trait for types that can be retrieved from current transaction fields.

Functions

get_field

Retrieves a field from the current transaction.

get_field_optional

Retrieves an optionally present field from the current transaction.