embedded-file-without-mime-type

All codes

• Type: error
• Kind: usage (the caller misused the API)

What happened

Under a PDF/A profile, Builder::attach added a file with an empty MIME type. A MIME type names the file’s format, such as text/xml.

Why

Software reading an archive years later needs to know what each attached file is. The PDF/A-3 standard for archival PDF (ISO 19005-3 §6.8) requires every embedded file to name its MIME type in the /Subtype of its stream, and Lamina PDF writes no /Subtype for an empty one.

How to fix

Pass the file’s MIME type to Attachment::new. For bytes of no particular type, use application/octet-stream.

Example

let options = BuildOptions::default().with_profile(Profile::PdfA3b);
let mut builder = Builder::new(options);
builder.attach(Attachment::new("invoice.xml", xml, ""));
builder.finish()?; // embedded-file-without-mime-type: pass "text/xml"

Data fields

• profile: the profile, such as PDF/A-3b.
• name: the file’s name (untrusted: the caller’s text).