migrate docs to mdx

website/docs/language/functions/filebase64sha256.mdx

@@ -0,0 +1,16 @@
+---
+page_title: filebase64sha256 - Functions - Configuration Language
+description: |-
+  The filebase64sha256 function computes the SHA256 hash of the contents of
+  a given file and encodes it with Base64.
+sidebar_title: filebase64sha256
+---
+
+# `filebase64sha256` Function
+
+`filebase64sha256` is a variant of [`base64sha256`](/language/functions/base64sha256)
+that hashes the contents of a given file rather than a literal string.
+
+This is similar to `base64sha256(file(filename))`, but
+because [`file`](/language/functions/file) accepts only UTF-8 text it cannot be used to
+create hashes for binary files.