Base64

Base64 byte strings in Internet Object

A Base64 Byte String in Internet Object is a sequence of binary data encoded in Base64 format, prefixed with b and enclosed in either single quotes (' U+0027) or double quotes (" U+0022). Byte strings are ideal for representing binary data such as images, encrypted content, cryptographic keys, or any arbitrary sequence of bytes in a text-based format.

Base64 byte strings are scalar values that represent binary data. The content between the quotes must be valid Base64 encoding according to RFC 4648.

Syntax

A Base64 byte string is prefixed with b and enclosed in either single or double quotes. The content must be valid Base64 encoding.

base64String = "b" (singleQuotedBase64 | doubleQuotedBase64)
singleQuotedBase64 = "'" base64Content "'"
doubleQuotedBase64 = '"' base64Content '"'
base64Content = { base64Character }
base64Character = "A" | "B" | "C" | ... | "Z" | "a" | "b" | ... | "z" | "0" | "1" | ... | "9" | "+" | "/" | "="

Structural Characters

The following characters are used to structure Base64 byte strings:

Symbol	Name	Unicode	Description
b	Byte Prefix	U+0062	Indicates Base64 byte string type
'	Single Quote	U+0027	Encloses Base64 content
"	Double Quote	U+0022	Encloses Base64 content
A-Z	Uppercase Letters	U+0041-U+005A	Base64 alphabet
a-z	Lowercase Letters	U+0061-U+007A	Base64 alphabet
0-9	Digits	U+0030-U+0039	Base64 alphabet
+	Plus Sign	U+002B	Base64 alphabet
/	Forward Slash	U+002F	Base64 alphabet
=	Equals Sign	U+003D	Base64 padding character

Note: Only valid Base64 characters are allowed within the quotes. Invalid characters will result in a parsing error.

Valid Forms

Examples of valid Base64 byte strings:

b'SGVsbG8gV29ybGQ='                    # "Hello World" in Base64
b"SGVsbG8gV29ybGQ="                    # Same as above with double quotes
b'iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVR42mP8/5+hHgAHggJ/PchI7wAAAABJRU5ErkJggg=='  # PNG image data
b'QWxhZGRpbjpvcGVuIHNlc2FtZQ=='        # "Aladdin:open sesame" in Base64
b''                                    # Empty byte string
b""                                    # Empty byte string (double quotes)
b'TWFu'                                # "Man" in Base64
b'TWE='                                # "Ma" in Base64 (with padding)
b'TQ=='                                # "M" in Base64 (with padding)

Optional Behaviors

• Whitespace: Leading and trailing whitespace around the quotes are ignored. Internal whitespace within the Base64 content is not allowed.

• Empty Representation: Empty byte strings are supported (b'' or b"").

• Case Sensitivity: The prefix must be lowercase b. The Base64 content is case-sensitive as per RFC 4648.

• Padding: Proper Base64 padding with = characters is required for correct decoding.

• Validation: The parser validates that the content is valid Base64 and can be decoded to binary data.

Invalid Forms

Examples of invalid Base64 byte strings:

bSGVsbG8=                             # ✗ Missing quotes
b'SGVsbG8 gV29ybGQ='                  # ✗ Space within Base64 content
b'SGVsbG8@V29ybGQ='                   # ✗ Invalid character '@' in Base64
b'SGVsbG8'                            # ✗ Invalid Base64 (missing padding)
b'SGVsbG8gV29ybGQ'                    # ✗ Invalid Base64 (incomplete)
B'SGVsbG8gV29ybGQ=                    # ✗ Missing closing quote
b''SGVsbG8gV29ybGQ=''                 # ✗ Double quotes around content

Preservation of Structure

Internet Object preserves:

• The exact Base64 encoding as written

• The choice of single or double quotes

• The lowercase b prefix

It does not interpret or enforce:

• The format or structure of the decoded binary data

• Application-specific constraints on the binary content

• Compression or encoding within the binary data

Decoding Behavior

When processed by an Internet Object parser:

• The Base64 content is decoded into a sequence of bytes

• The resulting binary data is typically represented as a byte array or buffer

• Invalid Base64 content results in a parsing error

• The decoded data maintains the exact binary representation

See Also

• Values Overview

• Base64 Schema