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Base64

Base64 encoding and decoding helpers.

3 exports Added in v4.0.0 Source

Decoding

decode

Added in v4.0.0 Source

Decodes a Base64 (RFC 4648) string into bytes safely.

When to use

Use to decode a standard padded Base64 string into bytes without throwing on invalid input.

Details

Returns Result.succeed with a Uint8Array when decoding succeeds, or Result.fail with an EncodingError when the input is not valid Base64.

Signature

declare function decode(str: string): Result<Uint8Array<ArrayBufferLike>, EncodingError>

Example

(Decoding Base64 bytes)

import { Result } from "effect"
import { Base64 } from "effect/encoding"
Base64.decode("SGVsbG8=") // => Result.succeed(new Uint8Array([72, 101, 108, 108, 111]))

decodeString

Added in v4.0.0 Source

Decodes a Base64 (RFC 4648) string into UTF-8 text safely.

When to use

Use to decode a standard padded Base64 string into UTF-8 text without throwing on invalid input.

Details

Returns Result.succeed with the decoded text when decoding succeeds, or Result.fail with an EncodingError when the input is not valid Base64.

Signature

declare function decodeString(str: string): Result<string, EncodingError>

Example

(Decoding Base64 strings)

import { Result } from "effect"
import { Base64 } from "effect/encoding"
Base64.decodeString("aGVsbG8=") // => Result.succeed("hello")

Encoding

encode

Added in v4.0.0 Source

Encodes the given value into a Base64 (RFC 4648) string.

When to use

Use to encode text or bytes as a standard padded Base64 string for storage or transport.

Details

String inputs are encoded as UTF-8 bytes before Base64 encoding. Uint8Array inputs are encoded directly. The output uses the standard RFC 4648 alphabet with = padding.

See

  • decode for decoding standard Base64 to bytes
  • decodeString for decoding standard Base64 to UTF-8 text

Signature

declare const encode: (input: Uint8Array | string) => string

Example

(Encoding Base64 strings and bytes)

import { Base64 } from "effect/encoding"
Base64.encode("hello") // => "aGVsbG8="
const bytes = new Uint8Array([72, 101, 108, 108, 111])
Base64.encode(bytes) // => "SGVsbG8="