from email.message import EmailMessage import mimetypes from io import BytesIO from pathlib import Path from typing import TYPE_CHECKING, Dict, Union, ByteString from pathlib import Path from redmail.utils import is_bytes from redmail.utils import import_from_string from email.utils import make_msgid, parseaddr from jinja2.environment import Template, Environment from markupsafe import Markup # We try to import matplotlib and PIL but if fails, they will be None from .utils import PIL, plt, pd, css_inline if TYPE_CHECKING: # For type hinting from pandas import DataFrame class BodyImage: "Utility class to represent image on HTML" def __init__(self, cid, obj, name=None): self.cid = cid self.obj = obj self.name = name def __str__(self): return f'' @property def src(self): return f'cid:{ self.cid }' class Body: def __init__(self, jinja_env:Environment, template:Template=None, table_template:Template=None, use_jinja=True): self.template = template self.table_template = table_template self.jinja_env = jinja_env self.use_jinja = use_jinja def render_body(self, body:str, jinja_params:dict): if body is not None and self.template is not None: raise ValueError("Either body or template must be specified but not both.") if body is not None: template = self.jinja_env.from_string(body) else: template = self.template return template.render(**jinja_params) def render_table(self, tbl, extra=None): # TODO: Nicer tables. # https://stackoverflow.com/a/55356741/13696660 # Email HTML (generally) does not support CSS if pd is None: raise ImportError("Missing package 'pandas'. Prettifying tables requires Pandas.") from pandas.io.formats.style import Styler extra = {} if extra is None else extra # Allow for pandas styler object, convert to inline CSS for email client rendering # https://pandas.pydata.org/docs/reference/api/pandas.io.formats.style.Styler.html if isinstance(tbl, Styler): if css_inline is None: raise ImportError("Missing package 'css_inline'. Prettifying tables with Pandas styler requires css_inline.") inliner = css_inline.CSSInliner() return inliner.inline(tbl.to_html()) df = pd.DataFrame(tbl) tbl_html = self.table_template.render({"df": df, **extra}) return Markup(tbl_html) def render(self, cont:str, tables=None, jinja_params=None): tables = {} if tables is None else tables jinja_params = {} if jinja_params is None else jinja_params tables = { name: self.render_table(tbl) for name, tbl in tables.items() } return self.render_body(cont, jinja_params={**tables, **jinja_params}) class TextBody(Body): def attach(self, msg:EmailMessage, text:str, **kwargs): if self.use_jinja: text = self.render(text, **kwargs) msg.set_content(text) class HTMLBody(Body): def __init__(self, domain:str=None, **kwargs): super().__init__(**kwargs) self.domain = domain def attach(self, msg:EmailMessage, html:str, images: Dict[str, Union[Path, str, bytes]]=None, **kwargs): """Render email HTML Parameters ---------- msg : EmailMessage Message of the email. html : str HTML that may contain Jinja syntax. body_images : dict of path-likes, bytes Images to embed to the HTML. The dict keys correspond to variables in the html. body_tables : dict of pd.DataFrame Tables to embed to the HTML jinja_params : dict Extra Jinja parameters for the HTML. """ if self.use_jinja: domain = self.domain html, cids = self.render( html, images=images, domain=domain, **kwargs ) msg.add_alternative(html, subtype='html') if self.use_jinja and images is not None: # https://stackoverflow.com/a/49098251/13696660 html_msg = msg.get_payload()[-1] cid_path_mapping = {cids[name]: path for name, path in images.items()} self.attach_imgs(html_msg, cid_path_mapping) def render(self, html:str, images:Dict[str, Union[dict, bytes, Path]]=None, tables:Dict[str, 'DataFrame']=None, jinja_params:dict=None, domain=None): """Render Email HTML body (sets cid for image sources and adds data as other parameters) Parameters ---------- html : str HTML (template) to be rendered with images, tables etc. May contain... images : list-like, optional A list-like of images to be rendered to the HTML. Values represent the Jinja variables found in the html and the images are rendered on those positions. tables : dict, optional A dict of tables to render to the HTML. The keys should represent variables in ``html`` and values should be Pandas dataframes to be rendered to the HTML. extra : dict, optional Extra items to be passed to the HTML Jinja template. table_theme : str, optional Theme to use for generating the HTML version of the table dataframes. See included files in the environment pybox.jinja2.envs.inline. The themes are stems of the files in templates/inline/table. Returns ------- str, dict Rendered HTML and Content-IDs to the images. """ images = {} if images is None else images # Define CIDs for images cids = { name: make_msgid(domain=domain) for name in images } html_images = { name: BodyImage(cid=cid[1:-1], name=name, obj=images[name]) # taking "<" and ">" from beginning and end for name, cid in cids.items() } # Tables to HTML jinja_params = {**jinja_params, **html_images} html = super().render(html, tables=tables, jinja_params=jinja_params) return html, cids def attach_imgs(self, msg_body:EmailMessage, imgs:Dict[str, Union[ByteString, str, Dict[str, Union[ByteString, str]]]]): """Attach CID images to Message Body Examples: --------- attach_imgs(..., {"<>"}) """ for cid, img in imgs.items(): if is_bytes(img) or isinstance(img, BytesIO): # We just assume the user meant PNG. If not, it should have been specified img_content = img.read() if hasattr(img, "read") else img kwds = { 'maintype': 'image', 'subtype': 'png', } elif isinstance(img, dict): # Expecting dict explanation of bytes # ie. {"maintype": "image", "subtype": "png", "content": b'...'} # Setting defaults img['maintype'] = img.get('maintype', 'image') # Validation required_keys = ("content", "subtype") if any(key not in img for key in required_keys): missing_keys = tuple(key for key in required_keys if key not in img) raise KeyError(f"Dict representation of an image missing keys: {missing_keys}") img_content = img.pop("content") kwds = img elif isinstance(img, Path) or (isinstance(img, str) and Path(img).is_file()): path = img maintype, subtype = mimetypes.guess_type(str(path))[0].split('/') with open(path, "rb") as img: img_content = img.read() kwds = { 'maintype': maintype, 'subtype': subtype, } elif plt is not None and isinstance(img, plt.Figure): buf = BytesIO() img.savefig(buf, format='png') buf.seek(0) img_content = buf.read() kwds = { 'maintype': 'image', 'subtype': 'png', } elif PIL is not None and isinstance(img, PIL.Image.Image): buf = BytesIO() img.save(buf, format='PNG') buf.seek(0) img_content = buf.read() kwds = { 'maintype': 'image', 'subtype': 'png', } else: # Cannot be figured out if isinstance(img, str): raise ValueError(f"Unknown image string '{img}'. Maybe incorrect path?") raise TypeError(f"Unknown image {repr(img)}") msg_body.add_related( img_content, cid=cid, **kwds )