--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libervia/backend/plugins/plugin_misc_attach.py	Fri Jun 02 11:49:51 2023 +0200
@@ -0,0 +1,278 @@
+#!/usr/bin/env python3
+
+# SàT plugin for attaching files
+# Copyright (C) 2009-2021 Jérôme Poisson (goffi@goffi.org)
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+from collections import namedtuple
+import mimetypes
+from pathlib import Path
+import shutil
+import tempfile
+from typing import Callable, Optional
+
+from twisted.internet import defer
+
+from libervia.backend.core import exceptions
+from libervia.backend.core.constants import Const as C
+from libervia.backend.core.core_types import SatXMPPEntity
+from libervia.backend.core.i18n import _
+from libervia.backend.core.log import getLogger
+from libervia.backend.tools import utils
+from libervia.backend.tools import image
+
+
+log = getLogger(__name__)
+
+
+PLUGIN_INFO = {
+    C.PI_NAME: "File Attach",
+    C.PI_IMPORT_NAME: "ATTACH",
+    C.PI_TYPE: C.PLUG_TYPE_MISC,
+    C.PI_MODES: C.PLUG_MODE_BOTH,
+    C.PI_DEPENDENCIES: ["UPLOAD"],
+    C.PI_MAIN: "AttachPlugin",
+    C.PI_HANDLER: "no",
+    C.PI_DESCRIPTION: _("""Attachments handler"""),
+}
+
+
+AttachmentHandler = namedtuple('AttachmentHandler', ['can_handle', 'attach', 'priority'])
+
+
+class AttachPlugin:
+
+    def __init__(self, host):
+        log.info(_("plugin Attach initialization"))
+        self.host = host
+        self._u = host.plugins["UPLOAD"]
+        host.trigger.add("sendMessage", self._send_message_trigger)
+        host.trigger.add("sendMessageComponent", self._send_message_trigger)
+        self._attachments_handlers = {'clear': [], 'encrypted': []}
+        self.register(self.default_can_handle, self.default_attach, False, -1000)
+
+    def register(self, can_handle, attach, encrypted=False, priority=0):
+        """Register an attachments handler
+
+        @param can_handle(callable, coroutine, Deferred): a method which must return True
+            if this plugin can handle the upload, otherwise next ones will be tried.
+            This method will get client and mess_data as arguments, before the XML is
+            generated
+        @param attach(callable, coroutine, Deferred): attach the file
+            this method will get client and mess_data as arguments, after XML is
+            generated. Upload operation must be handled
+            hint: "UPLOAD" plugin can be used
+        @param encrypted(bool): True if the handler manages encrypted files
+            A handler can be registered twice if it handle both encrypted and clear
+            attachments
+        @param priority(int): priority of this handler, handler with higher priority will
+            be tried first
+        """
+        handler = AttachmentHandler(can_handle, attach, priority)
+        handlers = (
+            self._attachments_handlers['encrypted']
+            if encrypted else self._attachments_handlers['clear']
+        )
+        if handler in handlers:
+            raise exceptions.InternalError(
+                'Attachment handler has been registered twice, this should never happen'
+            )
+
+        handlers.append(handler)
+        handlers.sort(key=lambda h: h.priority, reverse=True)
+        log.debug(f"new attachments handler: {handler}")
+
+    async def attach_files(self, client, data):
+        """Main method to attach file
+
+        It will do generic pre-treatment, and call the suitable attachments handler
+        """
+        # we check attachment for pre-treatment like large image resizing
+        # media_type will be added if missing (and if it can be guessed from path)
+        attachments = data["extra"][C.KEY_ATTACHMENTS]
+        tmp_dirs_to_clean = []
+        for attachment in attachments:
+            if attachment.get(C.KEY_ATTACHMENTS_RESIZE, False):
+                path = Path(attachment["path"])
+                try:
+                    media_type = attachment[C.KEY_ATTACHMENTS_MEDIA_TYPE]
+                except KeyError:
+                    media_type = mimetypes.guess_type(path, strict=False)[0]
+                    if media_type is None:
+                        log.warning(
+                            _("Can't resize attachment of unknown type: {attachment}")
+                            .format(attachment=attachment))
+                        continue
+                    attachment[C.KEY_ATTACHMENTS_MEDIA_TYPE] = media_type
+
+                main_type = media_type.split('/')[0]
+                if main_type == "image":
+                    report = image.check(self.host, path)
+                    if report['too_large']:
+                        tmp_dir = Path(tempfile.mkdtemp())
+                        tmp_dirs_to_clean.append(tmp_dir)
+                        new_path = tmp_dir / path.name
+                        await image.resize(
+                            path, report["recommended_size"], dest=new_path)
+                        attachment["path"] = new_path
+                        log.info(
+                            _("Attachment {path!r} has been resized at {new_path!r}")
+                            .format(path=str(path), new_path=str(new_path)))
+                else:
+                    log.warning(
+                        _("Can't resize attachment of type {main_type!r}: {attachment}")
+                        .format(main_type=main_type, attachment=attachment))
+
+        if client.encryption.is_encryption_requested(data):
+            handlers = self._attachments_handlers['encrypted']
+        else:
+            handlers = self._attachments_handlers['clear']
+
+        for handler in handlers:
+            can_handle = await utils.as_deferred(handler.can_handle, client, data)
+            if can_handle:
+                break
+        else:
+            raise exceptions.NotFound(
+                _("No plugin can handle attachment with {destinee}").format(
+                destinee = data['to']
+            ))
+
+        await utils.as_deferred(handler.attach, client, data)
+
+        for dir_path in tmp_dirs_to_clean:
+            log.debug(f"Cleaning temporary directory at {dir_path}")
+            shutil.rmtree(dir_path)
+
+        return data
+
+    async def upload_files(
+        self,
+        client: SatXMPPEntity,
+        data: dict,
+        upload_cb: Optional[Callable] = None
+    ):
+        """Upload file, and update attachments
+
+        invalid attachments will be removed
+        @param client:
+        @param data(dict): message data
+        @param upload_cb(coroutine, Deferred, None): method to use for upload
+            if None, upload method from UPLOAD plugin will be used.
+            Otherwise, following kwargs will be used with the cb:
+                - client
+                - filepath
+                - filename
+                - options
+            the method must return a tuple similar to UPLOAD plugin's upload method,
+            it must contain:
+                - progress_id
+                - a deferred which fire download URL
+        """
+        if upload_cb is None:
+            upload_cb = self._u.upload
+
+        uploads_d = []
+        to_delete = []
+        attachments = data["extra"]["attachments"]
+
+        for attachment in attachments:
+            if "url" in attachment and not "path" in attachment:
+                log.debug(f"attachment is external, we don't upload it: {attachment}")
+                continue
+            try:
+                # we pop path because we don't want it to be stored, as the file can be
+                # only in a temporary location
+                path = Path(attachment.pop("path"))
+            except KeyError:
+                log.warning("no path in attachment: {attachment}")
+                to_delete.append(attachment)
+                continue
+
+            if "url" in attachment:
+                url = attachment.pop('url')
+                log.warning(
+                    f"unexpected URL in attachment: {url!r}\nattachment: {attachment}"
+                )
+
+            try:
+                name = attachment["name"]
+            except KeyError:
+                name = attachment["name"] = path.name
+
+            attachment["size"] = path.stat().st_size
+
+            extra = {
+                "attachment": attachment
+            }
+            progress_id = attachment.pop("progress_id", None)
+            if progress_id:
+                extra["progress_id"] = progress_id
+            check_certificate = self.host.memory.param_get_a(
+                "check_certificate", "Connection", profile_key=client.profile)
+            if not check_certificate:
+                extra['ignore_tls_errors'] = True
+                log.warning(
+                    _("certificate check disabled for upload, this is dangerous!"))
+
+            __, upload_d = await upload_cb(
+                client=client,
+                filepath=path,
+                filename=name,
+                extra=extra,
+            )
+            uploads_d.append(upload_d)
+
+        for attachment in to_delete:
+            attachments.remove(attachment)
+
+        upload_results = await defer.DeferredList(uploads_d)
+        for idx, (success, ret) in enumerate(upload_results):
+            attachment = attachments[idx]
+
+            if not success:
+                # ret is a failure here
+                log.warning(f"error while uploading {attachment}: {ret}")
+                continue
+
+            attachment["url"] = ret
+
+        return data
+
+    def _attach_files(self, data, client):
+        return defer.ensureDeferred(self.attach_files(client, data))
+
+    def _send_message_trigger(
+        self, client, mess_data, pre_xml_treatments, post_xml_treatments):
+        if mess_data['extra'].get(C.KEY_ATTACHMENTS):
+            post_xml_treatments.addCallback(self._attach_files, client=client)
+        return True
+
+    async def default_can_handle(self, client, data):
+        return True
+
+    async def default_attach(self, client, data):
+        await self.upload_files(client, data)
+        # TODO: handle xhtml-im
+        body_elt = data["xml"].body
+        if body_elt is None:
+            body_elt = data["xml"].addElement("body")
+        attachments = data["extra"][C.KEY_ATTACHMENTS]
+        if attachments:
+            body_links = '\n'.join(a['url'] for a in attachments)
+            if str(body_elt).strip():
+                # if there is already a body, we add a line feed before the first link
+                body_elt.addContent('\n')
+            body_elt.addContent(body_links)