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tm_base64encode Function

tm_base64encode applies Base64 encoding to a string.

Terraform uses the "standard" Base64 alphabet as defined in RFC 4648 section 4.

Strings in the Terraform language are sequences of unicode characters rather than bytes, so this function will first encode the characters from the string as UTF-8, and then apply Base64 encoding to the result.

The Terraform language applies Unicode normalization to all strings, and so passing a string through tm_base64decode and then tm_base64encode may not yield the original result exactly.

While we do not recommend manipulating large, raw binary data in the Terraform language, Base64 encoding is the standard way to represent arbitrary byte sequences, and so resource types that accept or return binary data will use Base64 themselves, and so this function exists primarily to allow string data to be easily provided to resource types that expect Base64 bytes.

tm_base64encode is, in effect, a shorthand for calling tm_textencodebase64 with the encoding name set to UTF-8.


tm_base64encode("Hello World")
  • tm_base64decode performs the opposite operation, decoding Base64 data and interpreting it as a UTF-8 string.
  • tm_textencodebase64 is a more general function that supports character encodings other than UTF-8.
  • tm_base64gzip applies gzip compression to a string and returns the result with Base64 encoding all in one operation.
  • tm_filebase64 reads a file from the local filesystem and returns its raw bytes with Base64 encoding, without creating an intermediate Unicode string.