feat: issue2551068 - Provide way to retrieve file/msg data via rest endpoint. Use Allow header to change format of /binary_content endpoint. If Allow header for endpoint is not application/json, it will be matched against the mime type for the file. */*, text/* are supported and will return the native mime type if present. Changes: move */* mime type from static dict of supported types. It was hardcoded to return json only. Now it can return a matching non-json mime type for the /binary_content endpoint. Edited some errors to explicitly add */* mime type. Cleanups to use ', ' separation in lists of valid mime types rather than just space separated. Remove ETag header when sending raw content. See issue 2551375 for background. Doc added to rest.txt. Small format fix up (add dash) in CHANGES.txt. Make passing an unset/None/False accept_mime_type to format_dispatch_output a 500 error. This used to be the fallback to produce a 406 error after all processing had happened. It should no longer be possible to take that code path as all 406 errors (with valid accept_mime_types) are generated before processing takes place. Make format_dispatch_output handle output other than json/xml so it can send back binary_content data. Removed a spurious client.response_code = 400 that seems to not be used. Tests added for all code paths. Database setup for tests msg and file entry. This required a file upload test to change so it doesn't look for file1 as the link returned by the upload. Download the link and verify the data rather than verifying the link. Multiple formatting changes to error messages to make all lists of valid mime types ', ' an not just space separated.

##############################################################################
#
# Copyright (c) 2001, 2002 Zope Corporation and Contributors.
# All Rights Reserved.
#
# This software is subject to the provisions of the Zope Public License,
# Version 2.0 (ZPL).  A copy of the ZPL should accompany this distribution.
# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
# FOR A PARTICULAR PURPOSE.
#
##############################################################################
"""Translation context object for the TALInterpreter's I18N support.

The translation context provides a container for the information
needed to perform translation of a marked string from a page template.
"""

DEFAULT_DOMAIN = "default"

class TranslationContext:
    """Information about the I18N settings of a TAL processor."""

    def __init__(self, parent=None, domain=None, target=None, source=None):
        if parent:
            if not domain:
                domain = parent.domain
            if not target:
                target = parent.target
            if not source:
                source = parent.source
        elif domain is None:
            domain = DEFAULT_DOMAIN

        self.parent = parent
        self.domain = domain
        self.target = target
        self.source = source