#! /usr/bin/python # -*- coding: utf-8 -*- """ Secretary This project is a document engine which make use of LibreOffice documents as templates and use the semantics of jinja2 to control variable printing and control flow. To render a template: engine = Renderer() result = engine.render(template_file, foo=bar, ...) Copyright (c) 2012-2015 By: * Christopher Ramirez * Andrés Reyes Monge (github.com/armonge) * Anton Kochnev (github.com/ak04nv) * DieterBuys (github.com/DieterBuys) Licensed under the MIT license. """ from __future__ import unicode_literals, print_function import io import re import sys import logging import zipfile from os import path from mimetypes import guess_type, guess_extension from uuid import uuid4 from xml.dom.minidom import parseString from xml.parsers.expat import ExpatError, ErrorString from jinja2 import Environment, Undefined from markupsafe import Markup PY2 = sys.version_info < (3, 0) if PY2: from urllib import unquote else: from urllib.parse import unquote xrange = range basestring = (str, bytes) FLOW_REFERENCES = { 'text:p' : 'text:p', 'paragraph' : 'text:p', 'before::paragraph' : 'text:p', 'after::paragraph' : 'text:p', 'table:table-row' : 'table:table-row', 'table-row' : 'table:table-row', 'row' : 'table:table-row', 'before::table-row' : 'table:table-row', 'after::table-row' : 'table:table-row', 'before::row' : 'table:table-row', 'after::row' : 'table:table-row', 'table:table-cell' : 'table:table-cell', 'table-cell' : 'table:table-cell', 'cell' : 'table:table-cell', 'before::table-cell' : 'table:table-cell', 'after::table-cell' : 'table:table-cell', 'before::cell' : 'table:table-cell', 'after::cell' : 'table:table-cell', } # ---- Exceptions class SecretaryError(Exception): pass class UndefinedSilently(Undefined): # Silently undefined, # see http://stackoverflow.com/questions/6182498 def silently_undefined(*args, **kwargs): return '' return_new = lambda *args, **kwargs: UndefinedSilently() __unicode__ = silently_undefined __str__ = silently_undefined __call__ = return_new __getattr__ = return_new # ************************************************ # # SECRETARY FILTERS # # ************************************************ def media_loader(f): def wrapper(*args, **kwargs): Renderer.__media_loader__ = f return wrapper def pad_string(value, length=5): value = str(value) return value.zfill(length) class Renderer(object): """ Main engine to convert and ODT document into a jinja compatible template. Basic use example: engine = Renderer() result = engine.render(template, var1=val1, var2=val2, ...) Renderer provides an environment property which should be used to add custom filters to the ODF render. engine = Renderer() engine.environment.filters['custom_filter'] = filterFn result = engine.render('template.odt', var1=val1, ...) """ def __init__(self, environment=None, **kwargs): """ Create a Renderer instance. args: environment: Use this jinja2 environment. If not specified, we create a new environment for this class instance. """ self.log = logging.getLogger(__name__) self.log.debug('Initing a Renderer instance\nTemplate') if environment: self.environment = environment else: self.environment = Environment(undefined=UndefinedSilently, autoescape=True) # Register filters self.environment.filters['pad'] = pad_string self.environment.filters['markdown'] = self.markdown_filter self.environment.filters['image'] = self.image_filter self.environment.globals['SafeValue'] = Markup self.media_path = kwargs.pop('media_path', '') self.media_callback = self.fs_loader self._compile_tags_expressions() def media_loader(self, callback): """This sets the the media loader. A user defined function which loads media. The function should take a template value, optionals args and kwargs. Is media exists should return a tuple whose first element if a file object type representing the media and its second elements is the media mimetype. See Renderer.fs_loader funcion for an example""" self.media_callback = callback return callback def _unpack_template(self, template): # And Open/libreOffice is just a ZIP file. Here we unarchive the file # and return a dict with every file in the archive self.log.debug('Unpacking template file') archive_files = {} archive = zipfile.ZipFile(template, 'r') for zfile in archive.filelist: archive_files[zfile.filename] = archive.read(zfile.filename) return archive_files self.log.debug('Unpack completed') def _pack_document(self, files): # Store to a zip files in files self.log.debug('packing document') zip_file = io.BytesIO() mimetype = files['mimetype'] del files['mimetype'] zipdoc = zipfile.ZipFile(zip_file, 'a', zipfile.ZIP_DEFLATED) # Store mimetype without without compression using a ZipInfo object # for compatibility with Py2.6 which doesn't have compress_type # parameter in ZipFile.writestr function mime_zipinfo = zipfile.ZipInfo('mimetype') zipdoc.writestr(mime_zipinfo, mimetype) for fname, content in files.items(): zipdoc.writestr(fname, content) self.log.debug('Document packing completed') return zip_file @staticmethod def _inc_node_tags_count(node, is_block=False): """ Increase field count of node and its parents """ if node is None: return for attr in ['field_count', 'block_count', 'var_count']: if not hasattr(node, attr): setattr(node, attr, 0) node.field_count += 1 if is_block: node.block_count += 1 else: node.var_count += 1 Renderer._inc_node_tags_count(node.parentNode, is_block) def _compile_tags_expressions(self): self.tag_pattern = re.compile(r'(?is)^({0}|{1}).*({2}|{3})$'.format( self.environment.variable_start_string, self.environment.block_start_string, self.environment.variable_end_string, self.environment.block_end_string )) self.variable_pattern = re.compile(r'(?is)({0})(.*)({1})$'.format( self.environment.variable_start_string, self.environment.variable_end_string )) self.block_pattern = re.compile(r'(?is)({0})(.*)({1})$'.format( self.environment.block_start_string, self.environment.block_end_string )) self._compile_escape_expressions() def _compile_escape_expressions(self): # Compiles escape expressions self.escape_map = dict() unescape_rules = { r'>': r'>', r'<': r'<', r'&': r'&', r'"': r'"', r''': r'\'', } for key, value in unescape_rules.items(): exp = r'(?is)(({0}|{1})[^{3}{4}]*?)({2})([^{0}{1}]*?({3}|{4}))' key = re.compile(exp.format( self.environment.variable_start_string, self.environment.block_start_string, key, self.environment.variable_end_string, self.environment.block_end_string )) self.escape_map[key] = r'\1{0}\4'.format(value) def _is_jinja_tag(self, tag): """ Returns True is tag (str) is a valid jinja instruction tag. """ return len(self.tag_pattern.findall(tag)) > 0 def _is_block_tag(self, tag): """ Returns True is tag (str) is a jinja flow control tag. """ return len(self.block_pattern.findall(tag)) > 0 def _tags_in_document(self, document): """ Yields a list of available jinja instructions tags in document. """ tags = document.getElementsByTagName('text:text-input') for tag in tags: if not tag.hasChildNodes(): continue content = tag.childNodes[0].data.strip() if not self._is_jinja_tag(content): continue yield tag def _census_tags(self, document): """ Make a census of all available jinja tags in document. We count all the children tags nodes within their parents. This process is necesary to automaticaly avoid generating invalid documents when mixing block tags in differents parts of a document. """ for tag in self._tags_in_document(document): content = tag.childNodes[0].data.strip() block_tag = self._is_block_tag(content) self._inc_node_tags_count(tag.parentNode, block_tag) def _prepare_document_tags(self, document): """ Here we search for every field node present in xml_document. For each field we found we do: * if field is a print field ({{ field }}), we replace it with a node. * if field is a control flow ({% %}), then we find immediate node of type indicated in field's `text:description` attribute and replace the whole node and its childrens with field's content. If `text:description` attribute starts with `before::` or `after::`, then we move field content before or after the node in description. If no `text:description` is available, find the immediate common parent of this and any other field and replace its child and original parent of field with the field content. e.g.: original {% for bar in bars %} {{ bar }} {% endfor %}
After processing: {% for bar in bars %} {{ bar }} {% endfor %}
""" # -------------------------------------------------------------------- # # We have to replace a node, let's call it "placeholder", with the # content of our jinja tag. The placeholder can be a node with all its # children. Node's "text:description" attribute indicates how far we # can scale up in the tree hierarchy to get our placeholder node. When # said attribute is not present, then we scale up until we find a # common parent for this tag and any other tag. # -------------------------------------------------------------------- # self.log.debug('Preparing document tags') self._census_tags(document) for tag in self._tags_in_document(document): placeholder = tag content = tag.childNodes[0].data.strip() is_block = self._is_block_tag(content) scale_to = tag.getAttribute('text:description').strip().lower() if content.lower().find('|markdown') > 0: # Take whole paragraph when handling a markdown field scale_to = 'text:p' if scale_to: if FLOW_REFERENCES.get(scale_to, False): placeholder = self._parent_of_type( tag, FLOW_REFERENCES[scale_to] ) new_node = self.create_text_node(document, content) elif is_block: # expand up the placeholder until a shared parent is found while not placeholder.parentNode.field_count > 1: placeholder = placeholder.parentNode if placeholder: new_node = self.create_text_node(document, content) else: new_node = self.create_text_span_node(document, content) placeholder_parent = placeholder.parentNode if not scale_to.startswith('after::'): placeholder_parent.insertBefore(new_node, placeholder) else: if placeholder.isSameNode(placeholder_parent.lastChild): placeholder_parent.appendChild(new_node) else: placeholder_parent.insertBefore( new_node, placeholder.nextSibling ) if scale_to.startswith(('after::', 'before::')): # Don't remove whole field tag, only "text:text-input" container placeholder = self._parent_of_type(tag, 'text:p') placeholder_parent = placeholder.parentNode # Finally, remove the placeholder placeholder_parent.removeChild(placeholder) def _unescape_entities(self, xml_text): """ Unescape links and '&', '<', '"' and '>' within jinja instructions. The regexs rules used here are compiled in _compile_escape_expressions. """ for regexp, replacement in self.escape_map.items(): while True: xml_text, substitutions = regexp.subn(replacement, xml_text) if not substitutions: break return self._unescape_links(xml_text) def _unescape_links(self, xml_text): """Fix Libreoffice auto escaping of xlink:href attribute values. This unescaping is only done on 'secretary' scheme URLs.""" robj = re.compile(r'(?is)(xlink:href=\")secretary:(.*?)(\")') def replacement(match): return Markup(''.join([ match.group(1), self.variable_pattern.sub(r'\1 SafeValue(\2) \3', unquote(match.group(2))), match.group(3) ])) while True: xml_text, rep = robj.subn(replacement, xml_text) if not rep: break return xml_text def add_media_to_archive(self, media, mime, name=''): """ Adds to "Pictures" archive folder the file in `media` and register it into manifest file. """ extension = None if hasattr(media, 'name') and not name: extension = path.splitext(media.name) name = extension[0] extension = extension[1] if not extension: extension = guess_extension(mime) media_path = 'Pictures/%s%s' % (name, extension) media.seek(0) self.files[media_path] = media.read(-1) if hasattr(media, 'close'): media.close() files_node = self.manifest.getElementsByTagName('manifest:manifest')[0] node = self.create_node(self.manifest, 'manifest:file-entry', files_node) node.setAttribute('manifest:full-path', media_path) node.setAttribute('manifest:media-type', mime) return media_path def fs_loader(self, media, *args, **kwargs): """Loads a file from the file system. :param media: A file object or a relative or absolute path of a file. :type media: unicode """ if hasattr(media, 'seek') and hasattr(media, 'read'): return (media, 'image/jpeg') elif path.isfile(media): filename = media else: if not self.media_path: self.log.debug('media_path property not specified to load images from.') return filename = path.join(self.media_path, media) if not path.isfile(filename): self.log.debug('Media file "%s" does not exists.' % filename) return mime = guess_type(filename) return (open(filename, 'rb'), mime[0] if mime else None) def replace_images(self, xml_document): """Perform images replacements""" self.log.debug('Inserting images') frames = xml_document.getElementsByTagName('draw:frame') for frame in frames: if not frame.hasChildNodes(): continue key = frame.getAttribute('draw:name') if key not in self.template_images: continue # Get frame attributes frame_attrs = dict() for i in xrange(frame.attributes.length): attr = frame.attributes.item(i) frame_attrs[attr.name] = attr.value # Get child draw:image node and its attrs image_node = frame.childNodes[0] image_attrs = dict() for i in xrange(image_node.attributes.length): attr = image_node.attributes.item(i) image_attrs[attr.name] = attr.value # Request to media loader the image to use image = self.media_callback(self.template_images[key]['value'], *self.template_images[key]['args'], frame_attrs=frame_attrs, image_attrs=image_attrs, **self.template_images[key]['kwargs']) # Update frame and image node attrs (if they where updated in # media_callback call) for k, v in frame_attrs.items(): frame.setAttribute(k, v) for k, v in image_attrs.items(): image_node.setAttribute(k, v) # Keep original image reference value if isinstance(self.template_images[key]['value'], basestring): frame.setAttribute('draw:name', self.template_images[key]['value']) # Does the madia loader returned something? if not image: continue mname = self.add_media_to_archive(media=image[0], mime=image[1], name=key) if mname: image_node.setAttribute('xlink:href', mname) def _render_xml(self, xml_document, **kwargs): # Prepare the xml object to be processed by jinja2 self.log.debug('Rendering XML object') template_string = "" try: self.template_images = dict() self._prepare_document_tags(xml_document) xml_source = xml_document.toxml() xml_source = xml_source.encode('ascii', 'xmlcharrefreplace') jinja_template = self.environment.from_string( self._unescape_entities(xml_source.decode('utf-8')) ) result = jinja_template.render(**kwargs) final_xml = parseString(result.encode('ascii', 'xmlcharrefreplace')) if self.template_images: self.replace_images(final_xml) return final_xml except ExpatError as e: if not 'result' in locals(): result = xml_source near = result.split('\n')[e.lineno -1][e.offset-200:e.offset+200] raise ExpatError('ExpatError "%s" at line %d, column %d\nNear of: "[...]%s[...]"' % \ (ErrorString(e.code), e.lineno, e.offset, near)) except: self.log.error('Error rendering template:\n%s', xml_document.toprettyxml(), exc_info=True) self.log.error('Unescaped template was:\n{0}'.format(template_string)) raise finally: self.log.debug('Rendering xml object finished') def render(self, template, **kwargs): """ Render a template args: template: A template file. Could be a string or a file instance **kwargs: Template variables. Similar to jinja2 returns: A binary stream which contains the rendered document. """ self.log.debug('Initing a template rendering') self.files = self._unpack_template(template) self.render_vars = {} # Keep content and styles object since many functions or # filters may work with then self.content = parseString(self.files['content.xml']) self.styles = parseString(self.files['styles.xml']) self.manifest = parseString(self.files['META-INF/manifest.xml']) # Render content.xml keeping just 'office:body' node. rendered_content = self._render_xml(self.content, **kwargs) self.content.getElementsByTagName('office:document-content')[0].replaceChild( rendered_content.getElementsByTagName('office:body')[0], self.content.getElementsByTagName('office:body')[0] ) # Render styles.xml self.styles = self._render_xml(self.styles, **kwargs) self.log.debug('Template rendering finished') self.files['content.xml'] = self.content.toxml().encode('ascii', 'xmlcharrefreplace') self.files['styles.xml'] = self.styles.toxml().encode('ascii', 'xmlcharrefreplace') self.files['META-INF/manifest.xml'] = self.manifest.toxml().encode('ascii', 'xmlcharrefreplace') document = self._pack_document(self.files) return document.getvalue() def _parent_of_type(self, node, of_type): # Returns the first immediate parent of type `of_type`. # Returns None if nothing is found. if hasattr(node, 'parentNode'): if node.parentNode.nodeName.lower() == of_type: return node.parentNode else: return self._parent_of_type(node.parentNode, of_type) else: return None def create_node(self, xml_document, node_type, parent=None): """Creates a node in `xml_document` of type `node_type` and specified, as child of `parent`.""" node = xml_document.createElement(node_type) if parent: parent.appendChild(node) return node def create_text_span_node(self, xml_document, content): span = xml_document.createElement('text:span') text_node = self.create_text_node(xml_document, content) span.appendChild(text_node) return span def create_text_node(self, xml_document, text): """ Creates a text node """ return xml_document.createTextNode(text) def get_style_by_name(self, style_name): """ Search in for style_name. Return None if style_name is not found. Otherwise return the style node """ auto_styles = self.content.getElementsByTagName( 'office:automatic-styles')[0] if not auto_styles.hasChildNodes(): return None for style_node in auto_styles.childNodes: if style_node.hasAttribute('style:name') and \ (style_node.getAttribute('style:name') == style_name): return style_node return None def insert_style_in_content(self, style_name, attributes=None, **style_properties): """ Insert a new style into content.xml's node. Returns a reference to the newly created node """ auto_styles = self.content.getElementsByTagName('office:automatic-styles')[0] style_node = self.content.createElement('style:style') style_node.setAttribute('style:name', style_name) style_node.setAttribute('style:family', 'text') style_node.setAttribute('style:parent-style-name', 'Standard') if attributes: for k, v in attributes.items(): style_node.setAttribute('style:%s' % k, v) if style_properties: style_prop = self.content.createElement('style:text-properties') for k, v in style_properties.items(): style_prop.setAttribute('%s' % k, v) style_node.appendChild(style_prop) return auto_styles.appendChild(style_node) def markdown_filter(self, markdown_text): """ Convert a markdown text into a ODT formated text """ if not isinstance(markdown_text, basestring): return '' from xml.dom import Node from markdown_map import transform_map try: from markdown2 import markdown except ImportError: raise SecretaryError('Could not import markdown2 library. Install it using "pip install markdown2"') styles_cache = {} # cache styles searching html_text = markdown(markdown_text) encoded = html_text.encode('ascii', 'xmlcharrefreplace') if isinstance(encoded, bytes): # In PY3 bytes-like object needs convert to str encoded = encoded.decode('ascii') xml_object = parseString('%s' % encoded) # Transform HTML tags as specified in transform_map # Some tags may require extra attributes in ODT. # Additional attributes are indicated in the 'attributes' property for tag in transform_map: html_nodes = xml_object.getElementsByTagName(tag) for html_node in html_nodes: odt_node = xml_object.createElement(transform_map[tag]['replace_with']) # Transfer child nodes if html_node.hasChildNodes(): # We can't directly insert text into a text:list-item element. # The content of the item most be wrapped inside a container # like text:p. When there's not a double linebreak separating # list elements, markdown2 creates
  • elements without wraping # their contents inside a container. Here we automatically create # the container if one was not created by markdown2. if (tag=='li' and html_node.childNodes[0].localName != 'p'): container = xml_object.createElement('text:p') odt_node.appendChild(container) elif tag=='code': def traverse_preformated(node): if node.hasChildNodes(): for n in node.childNodes: traverse_preformated(n) else: container = xml_object.createElement('text:span') for text in re.split('(\n)', node.nodeValue.lstrip('\n')): if text == '\n': container.appendChild(xml_object.createElement('text:line-break')) else: container.appendChild(xml_object.createTextNode(text)) node.parentNode.replaceChild(container, node) traverse_preformated(html_node) container = odt_node else: container = odt_node for child_node in html_node.childNodes: container.appendChild(child_node.cloneNode(True)) # Add style-attributes defined in transform_map if 'style_attributes' in transform_map[tag]: for k, v in transform_map[tag]['style_attributes'].items(): odt_node.setAttribute('text:%s' % k, v) # Add defined attributes if 'attributes' in transform_map[tag]: for k, v in transform_map[tag]['attributes'].items(): odt_node.setAttribute(k, v) # copy original href attribute in tag if tag == 'a': if html_node.hasAttribute('href'): odt_node.setAttribute('xlink:href', html_node.getAttribute('href')) # Does the node need to create an style? if 'style' in transform_map[tag]: name = transform_map[tag]['style']['name'] if not name in styles_cache: style_node = self.get_style_by_name(name) if style_node is None: # Create and cache the style node style_node = self.insert_style_in_content( name, transform_map[tag]['style'].get('attributes', None), **transform_map[tag]['style']['properties']) styles_cache[name] = style_node html_node.parentNode.replaceChild(odt_node, html_node) def node_to_string(node): return node.toxml() ODTText = ''.join(node_as_str for node_as_str in map(node_to_string, xml_object.getElementsByTagName('html')[0].childNodes)) return Markup(ODTText) def image_filter(self, value, *args, **kwargs): """Store value into template_images and return the key name where this method stored it. The value returned it later used to load the image from media loader and finally inserted into the final ODT document.""" key = uuid4().hex self.template_images[key] = { 'value': value, 'args': args, 'kwargs': kwargs } return key def render_template(template, **kwargs): """ Render a ODF template file """ engine = Renderer(file) return engine.render(**kwargs) if __name__ == "__main__": import os from datetime import datetime def read(fname): return open(os.path.join(os.path.dirname(__file__), fname)).read() document = { 'datetime': datetime.now(), 'md_sample': read('README.md') } countries = [ {'country': 'United States', 'capital': 'Washington', 'cities': ['miami', 'new york', 'california', 'texas', 'atlanta']}, {'country': 'England', 'capital': 'London', 'cities': ['gales']}, {'country': 'Japan', 'capital': 'Tokio', 'cities': ['hiroshima', 'nagazaki']}, {'country': 'Nicaragua', 'capital': 'Managua', 'cities': ['leon', 'granada', 'masaya']}, {'country': 'Argentina', 'capital': 'Buenos aires'}, {'country': 'Chile', 'capital': 'Santiago'}, {'country': 'Mexico', 'capital': 'MExico City', 'cities': ['puebla', 'cancun']}, ] render = Renderer() result = render.render('simple_template.odt', countries=countries, document=document) output = open('rendered.odt', 'wb') output.write(result) print("Template rendering finished! Check rendered.odt file.")