mimetype.pl -- Determine mime-type for a file

Simple library to guess the mime-type from the extension of a file. As various applications need to do this type ofinferencing it seems worthwhile to place this functionality in an extensible library.

To be done

- Consider content handling (using the Unix file command)

- Allow parameters? (e.g. text/html; charset=UTF-8)

 file_mime_type(+FileName, -MimeType) is semidet

True when MimeType is the mime-type to be used for sending FileName. The default rules can be overridden and extended using the hook mime:mime_extension/2.

Arguments:

MimeType

- is a compound term of the form Type/SubType.

 mime:mime_extension(+Ext, -MimeType) is semidet[multifile]

Hook that is called by file_mime_type/2 before the default table is examined.

 file_content_type(+File:atom, -ContentType:atom) is det

 file_content_type(+File:atom, ?MediaType, -ContentType:atom) is det

True if File should be served using ContentType: ContentType. It takes the following steps:

1. Determine the media type using file_mime_type/2, unless already specified using file_content_type/3.
2. Determine it is a text file using text_mimetype/1
3. Use the charset from the Prolog flag default_charset

The behavior is controlled by several hooks and a flag.

• mime:mime_extension/2 defines the media type
• text_mimetype/1 defines the media type is text
• mime:charset/3 derives the charset for a file with a given media type, if the media type is text according to text_mimetype/1.
• If text_mimetype/1 succeeds and mime:charset/3 fails, the flag default_charset defines the charset unless it is set to -. The flag set by default to UTF-8 if the Prolog flag encoding is set to utf8.

 mime:charset(+File, +MediaType, -Charset) is semidet[multifile]

Hook that determines the Charset for File that has media type MediaType. This hook allows overruling file_content_type/2.

See also

- text_mimetype/1.

Re-exported predicates

The following predicates are exported from this file while their implementation is defined in imported modules or non-module files loaded by this module.

 file_content_type(+File:atom, -ContentType:atom) is det

 file_content_type(+File:atom, ?MediaType, -ContentType:atom) is det

True if File should be served using ContentType: ContentType. It takes the following steps:

1. Determine the media type using file_mime_type/2, unless already specified using file_content_type/3.
2. Determine it is a text file using text_mimetype/1
3. Use the charset from the Prolog flag default_charset

The behavior is controlled by several hooks and a flag.

• mime:mime_extension/2 defines the media type
• text_mimetype/1 defines the media type is text
• mime:charset/3 derives the charset for a file with a given media type, if the media type is text according to text_mimetype/1.
• If text_mimetype/1 succeeds and mime:charset/3 fails, the flag default_charset defines the charset unless it is set to -. The flag set by default to UTF-8 if the Prolog flag encoding is set to utf8.