[TS SDK v2] Add AccountAddress

ecosystem/typescript/sdk_v2/src/types/account_address.ts

@@ -0,0 +1,273 @@
+// Copyright © Aptos Foundation
+// SPDX-License-Identifier: Apache-2.0
+
+import { bytesToHex, hexToBytes } from "@noble/hashes/utils";
+import { Serializer, Deserializer, Bytes } from "../bcs";
+
+/**
+ * This enum is used to explain why an address was invalid.
+ */
+export enum AddressInvalidReason {
+  INCORRECT_NUMBER_OF_BYTES = "incorrect_number of bytes",
+  INVALID_HEX_CHARS = "invalid_hex_chars",
+  ADDRESS_TOO_SHORT = "address_too_short",
+  ADDRESS_TOO_LONG = "address_too_long",
+  LEADING_ZERO_X_REQUIRED = "leading_zero_x_required",
+  LONG_FORM_REQUIRED_UNLESS_SPECIAL = "long_form_required_unless_special",
+}
+
+/**
+ * This error is used to explain why an address was invalid.
+ */
+export class AddressInvalidError extends Error {
+  // This provides a programmatic way to access why an address was invalid. Downstream
+  // devs might want to use this to build their own error messages if the default error
+  // messages are not suitable for their use case.
+  public reason: AddressInvalidReason;
+
+  constructor(message: string, reason: AddressInvalidReason) {
+    super(message);
+    this.reason = reason;
+  }
+}
+
+/**
+ * NOTE: Only use this class for account addresses. For other hex data, e.g. transaction
+ * hashes, use the Hex class.
+ *
+ * AccountAddress is a helper class for working with account addresses. Account addresses,
+ * when represented as a string, generally look like this for example:
+ * - 0x1
+ * - 0xaa86fe99004361f747f91342ca13c426ca0cccb0c1217677180c9493bad6ef0c
+ *
+ * todo
+ */
+export class AccountAddress {
+  // The number of bytes that make up an account address.
+  static readonly LENGTH: number = 32;
+
+  // The length of an address string in long form without a leading 0x.
+  static readonly LONG_STRING_LENGTH: number = 64;
+
+  // This is the internal representation of an account address.
+  readonly address: Bytes;
+
+  static ADDRESS_ONE: AccountAddress = AccountAddress.fromString({ str: "0x1" });
+
+  static ADDRESS_TWO: AccountAddress = AccountAddress.fromString({ str: "0x2" });
+
+  static ADDRESS_THREE: AccountAddress = AccountAddress.fromString({ str: "0x3" });
+
+  static ADDRESS_FOUR: AccountAddress = AccountAddress.fromString({ str: "0x4" });
+
+  constructor(address: Bytes) {
+    if (address.length !== AccountAddress.LENGTH) {
+      throw new AddressInvalidError("Expected address of length 32", AddressInvalidReason.INCORRECT_NUMBER_OF_BYTES);
+    }
+    this.address = address;
+  }
+
+  /**
+   * NOTE: This function has strict parsing behavior. For relaxed behavior, please use
+   * the `fromStringRelaxed` function.
+   *
+   * Creates AccountAddress from a hex string.
+   *
+   * This function allows only the strictest formats defined by AIP 40. In short this
+   * means only the following formats are accepted:
+   *
+   * - LONG
+   * - SHORT for special addresses
+   *
+   * LONG is defined as 0x + 64 hex characters.
+   *
+   * SHORT for special addresses is 0x0 to 0xf inclusive.
+   *
+   * This means the following are not accepted:
+   * - SHORT for non-special addresses.
+   * - Any address without a leading 0x.
+   *
+   * Learn more about the different address formats by reading AIP 40:
+   * https://github.com/aptos-foundation/AIPs/blob/main/aips/aip-40.md
+   *
+   * @param str A hex string representing an account address.
+   */
+  static fromString(args: { str: string }): AccountAddress {
+    let input = args.str;
+
+    // Assert the string starts with 0x.
+    if (!input.startsWith("0x")) {
+      throw new AddressInvalidError(
+        "Hex string must start with a leading 0x.",
+        AddressInvalidReason.LEADING_ZERO_X_REQUIRED,
+      );
+    }
+
+    const address = AccountAddress.fromStringRelaxed(args);
+
+    // Assert that only special addresses can use short form.
+    if (input.slice(2).length !== this.LONG_STRING_LENGTH && !address.isSpecial()) {
+      throw new AddressInvalidError(
+        "Hex string is not a special address, it must be represented as 0x + 64 chars.",
+        AddressInvalidReason.LONG_FORM_REQUIRED_UNLESS_SPECIAL,
+      );
+    }
+
+    return address;
+  }
+
+  /**
+   * NOTE: This function has relaxed parsing behavior. For strict behavior, please use
+   * the `fromString` function.
+   *
+   * Creates AccountAddress from a hex string.
+   *
+   * This function allows all formats defined by AIP 40. In short this means the
+   * following formats are accepted:
+   *
+   * - LONG, with or without leading 0x
+   * - SHORT, with or without leading 0x
+   *
+   * LONG is 64 hex characters.
+   *
+   * SHORT is 1 to 63 hex characters.
+   *
+   * Learn more about the different address formats by reading AIP 40:
+   * https://github.com/aptos-foundation/AIPs/blob/main/aips/aip-40.md
+   *
+   * @param str A hex string representing an account address.
+   */
+  static fromStringRelaxed(args: { str: string }): AccountAddress {
+    let input = args.str;
+
+    // Remove leading 0x for parsing.
+    if (input.startsWith("0x")) {
+      input = input.slice(2);
+    }
+
+    // Ensure the address string is at least 1 character long.
+    if (input.length === 0) {
+      throw new AddressInvalidError(
+        "Hex string is too short, must be 1 to 64 chars long, excluding the leading 0x.",
+        AddressInvalidReason.ADDRESS_TOO_SHORT,
+      );
+    }
+
+    // Ensure the address string is not longer than 64 characters.
+    if (input.length > 64) {
+      throw new AddressInvalidError(
+        "Hex string is too long, must be 1 to 64 chars long, excluding the leading 0x.",
+        AddressInvalidReason.ADDRESS_TOO_LONG,
+      );
+    }
+
+    let addressBytes: Uint8Array;
+    try {
+      // Pad the address with leading zeroes so it is 64 chars long and then convert
+      // the hex string to bytes. Every two characters in a hex string constitutes a
+      // single byte. So a 64 length hex string becomes a 32 byte array.
+      addressBytes = hexToBytes(input.padStart(64, "0"));
+    } catch (e) {
+      const error = e as Error;
+      // At this point the only way this can fail is if the hex string contains
+      // invalid characters.
+      throw new AddressInvalidError(
+        `Hex characters are invalid: ${error.message}`,
+        AddressInvalidReason.INVALID_HEX_CHARS,
+      );
+    }
+
+    return new AccountAddress(addressBytes);
+  }
+
+  /**
+   * Check if the string is a valid AccountAddress.
+   *
+   * @param str A hex string representing an account address.
+   * @param relaxed If true, use relaxed parsing behavior. If false, use strict parsing behavior.
+   *
+   * @returns valud = true if the string is valid, valid = false if not. If the string
+   * is not valid, invalidReason will be set explaining why it is invalid.
+   */
+  static isValid(args: { str: string; relaxed?: boolean }): {
+    valid: boolean;
+    invalidReason: string | null;
+    invalidReasonCode: AddressInvalidReason | null;
+  } {
+    try {
+      if (args.relaxed) {
+        AccountAddress.fromStringRelaxed({ str: args.str });
+      } else {
+        AccountAddress.fromString({ str: args.str });
+      }
+      return { valid: true, invalidReason: null, invalidReasonCode: null };
+    } catch (e) {
+      const addressInvalidError = e as AddressInvalidError;
+      return {
+        valid: false,
+        invalidReason: addressInvalidError.message,
+        invalidReasonCode: addressInvalidError.reason,
+      };
+    }
+  }
+
+  /**
+   * Returns whether an address is special, where special is defined as 0x0 to 0xf
+   * inclusive. In other words, the last byte of the address must be < 0b10000 (16)
+   * and every other byte must be zero.
+   */
+  isSpecial(): boolean {
+    return (
+      this.address.slice(0, this.address.length - 1).every((byte) => byte === 0) &&
+      this.address[this.address.length - 1] < 0b10000
+    );
+  }
+
+  /**
+   * Conforms to AIP 40. TODO: Write more.
+   */
+  toString(): string {
+    let hex = bytesToHex(this.address);
+    if (this.isSpecial()) {
+      hex = hex[hex.length - 1];
+    }
+    return `0x${this.toStringWithoutPrefix()}`;
+  }
+
+  /**
+   * todo
+   */
+  toStringWithoutPrefix(): string {
+    let hex = bytesToHex(this.address);
+    if (this.isSpecial()) {
+      hex = hex[hex.length - 1];
+    }
+    return hex;
+  }
+
+  /*
+   * Whereas toString will format special addresses (as defined by isSpecial) using the
+   * short form (no leading 0s), this function will include leading zeroes. This is
+   * allowed as per AIP 40 if the need arises, but using toString is preferred.
+   */
+  toStringLong(): string {
+    return `0x${this.toStringLongWithoutPrefix()}`;
+  }
+
+  /*
+   * todo
+   */
+  toStringLongWithoutPrefix(): string {
+    return bytesToHex(this.address);
+  }
+
+  // For use with the BCS payload generation library.
+  serialize(serializer: Serializer): void {
+    serializer.serializeFixedBytes(this.address);
+  }
+
+  // For use with the BCS payload generation library.
+  static deserialize(deserializer: Deserializer): AccountAddress {
+    return new AccountAddress(deserializer.deserializeFixedBytes(AccountAddress.LENGTH));
+  }
+}

ecosystem/typescript/sdk_v2/src/types/index.ts

@@ -1,4 +1,5 @@
 export type AnyNumber = number | bigint;
 export type HexInput = string | Uint8Array;
 
+export * from "./account_address";
 export * from "./hex";