import warnings from django.core.mail import make_msgid from requests.structures import CaseInsensitiveDict from ..exceptions import AnymailConfigurationError, AnymailRequestsAPIError, AnymailWarning from ..message import AnymailRecipientStatus from ..utils import get_anymail_setting, timestamp from .base_requests import AnymailRequestsBackend, RequestsPayload class SendGridBackend(AnymailRequestsBackend): """ SendGrid API Email Backend """ def __init__(self, **kwargs): """Init options from Django settings""" # Auth requires *either* SENDGRID_API_KEY or SENDGRID_USERNAME+SENDGRID_PASSWORD esp_name = self.esp_name self.api_key = get_anymail_setting('api_key', esp_name=esp_name, kwargs=kwargs, default=None, allow_bare=True) self.username = get_anymail_setting('username', esp_name=esp_name, kwargs=kwargs, default=None, allow_bare=True) self.password = get_anymail_setting('password', esp_name=esp_name, kwargs=kwargs, default=None, allow_bare=True) if self.api_key is None and (self.username is None or self.password is None): raise AnymailConfigurationError( "You must set either SENDGRID_API_KEY or both SENDGRID_USERNAME and " "SENDGRID_PASSWORD in your Django ANYMAIL settings." ) self.generate_message_id = get_anymail_setting('generate_message_id', esp_name=esp_name, kwargs=kwargs, default=True) self.merge_field_format = get_anymail_setting('merge_field_format', esp_name=esp_name, kwargs=kwargs, default=None) # This is SendGrid's Web API v2 (because the Web API v3 doesn't support sending) api_url = get_anymail_setting('api_url', esp_name=esp_name, kwargs=kwargs, default="https://api.sendgrid.com/api/") if not api_url.endswith("/"): api_url += "/" super(SendGridBackend, self).__init__(api_url, **kwargs) def build_message_payload(self, message, defaults): return SendGridPayload(message, defaults, self) def parse_recipient_status(self, response, payload, message): parsed_response = self.deserialize_json_response(response, payload, message) try: sendgrid_message = parsed_response["message"] except (KeyError, TypeError): raise AnymailRequestsAPIError("Invalid SendGrid API response format", email_message=message, payload=payload, response=response) if sendgrid_message != "success": errors = parsed_response.get("errors", []) raise AnymailRequestsAPIError("SendGrid send failed: '%s'" % "; ".join(errors), email_message=message, payload=payload, response=response) # Simulate a per-recipient status of "queued": status = AnymailRecipientStatus(message_id=payload.message_id, status="queued") return {recipient.email: status for recipient in payload.all_recipients} class SendGridPayload(RequestsPayload): def __init__(self, message, defaults, backend, *args, **kwargs): self.all_recipients = [] # used for backend.parse_recipient_status self.generate_message_id = backend.generate_message_id self.message_id = None # Message-ID -- assigned in serialize_data unless provided in headers self.smtpapi = {} # SendGrid x-smtpapi field self.to_list = [] # needed for build_merge_data self.merge_field_format = backend.merge_field_format self.merge_data = None # late-bound per-recipient data self.merge_global_data = None http_headers = kwargs.pop('headers', {}) query_params = kwargs.pop('params', {}) if backend.api_key is not None: http_headers['Authorization'] = 'Bearer %s' % backend.api_key else: query_params['api_user'] = backend.username query_params['api_key'] = backend.password super(SendGridPayload, self).__init__(message, defaults, backend, params=query_params, headers=http_headers, *args, **kwargs) def get_api_endpoint(self): return "mail.send.json" def serialize_data(self): """Performs any necessary serialization on self.data, and returns the result.""" if self.generate_message_id: self.ensure_message_id() self.build_merge_data() if self.merge_data is not None: # Must *also* set smtpapi 'to' field so SG does batch send # (else all recipients would see each other's emails) self.smtpapi['to'] = [email.address for email in self.to_list] # Serialize x-smtpapi to json: if len(self.smtpapi) > 0: # If esp_extra was also used to set x-smtpapi, need to merge it if "x-smtpapi" in self.data: esp_extra_smtpapi = self.data["x-smtpapi"] for key, value in esp_extra_smtpapi.items(): if key == "filters": # merge filters (else it's difficult to mix esp_extra with other features) self.smtpapi.setdefault(key, {}).update(value) else: # all other keys replace any current value self.smtpapi[key] = value self.data["x-smtpapi"] = self.serialize_json(self.smtpapi) elif "x-smtpapi" in self.data: self.data["x-smtpapi"] = self.serialize_json(self.data["x-smtpapi"]) # Serialize extra headers to json: headers = self.data["headers"] self.data["headers"] = self.serialize_json(dict(headers.items())) return self.data def ensure_message_id(self): """Ensure message has a known Message-ID for later event tracking""" headers = self.data["headers"] if "Message-ID" not in headers: # Only make our own if caller hasn't already provided one headers["Message-ID"] = self.make_message_id() self.message_id = headers["Message-ID"] # Workaround for missing message ID (smtp-id) in SendGrid engagement events # (click and open tracking): because unique_args get merged into the raw event # record, we can supply the 'smtp-id' field for any events missing it. self.smtpapi.setdefault('unique_args', {})['smtp-id'] = self.message_id def make_message_id(self): """Returns a Message-ID that could be used for this payload Tries to use the from_email's domain as the Message-ID's domain """ try: _, domain = self.data["from"].split("@") except (AttributeError, KeyError, TypeError, ValueError): domain = None return make_msgid(domain=domain) def build_merge_data(self): """Set smtpapi['sub'] and ['section']""" if self.merge_data is not None: # Convert from {to1: {a: A1, b: B1}, to2: {a: A2}} (merge_data format) # to {a: [A1, A2], b: [B1, ""]} ({field: [data in to-list order], ...}) all_fields = set() for recipient_data in self.merge_data.values(): all_fields = all_fields.union(recipient_data.keys()) recipients = [email.email for email in self.to_list] if self.merge_field_format is None and all(field.isalnum() for field in all_fields): warnings.warn( "Your SendGrid merge fields don't seem to have delimiters, " "which can cause unexpected results with Anymail's merge_data. " "Search SENDGRID_MERGE_FIELD_FORMAT in the Anymail docs for more info.", AnymailWarning) sub_field_fmt = self.merge_field_format or '{}' sub_fields = {field: sub_field_fmt.format(field) for field in all_fields} self.smtpapi['sub'] = { # If field data is missing for recipient, use (formatted) field as the substitution. # (This allows default to resolve from global "section" substitutions.) sub_fields[field]: [self.merge_data.get(recipient, {}).get(field, sub_fields[field]) for recipient in recipients] for field in all_fields } if self.merge_global_data is not None: section_field_fmt = self.merge_field_format or '{}' self.smtpapi['section'] = { section_field_fmt.format(field): data for field, data in self.merge_global_data.items() } # # Payload construction # def init_payload(self): self.data = {} # {field: [multiple, values]} self.files = {} self.data['headers'] = CaseInsensitiveDict() # headers keys are case-insensitive def set_from_email(self, email): self.data["from"] = email.email if email.name: self.data["fromname"] = email.name def set_to(self, emails): self.to_list = emails # track for later use by build_merge_data self.set_recipients('to', emails) def set_recipients(self, recipient_type, emails): assert recipient_type in ["to", "cc", "bcc"] if emails: self.data[recipient_type] = [email.email for email in emails] empty_name = " " # SendGrid API balks on complete empty name fields self.data[recipient_type + "name"] = [email.name or empty_name for email in emails] self.all_recipients += emails # used for backend.parse_recipient_status def set_subject(self, subject): self.data["subject"] = subject def set_reply_to(self, emails): # Note: SendGrid mangles the 'replyto' API param: it drops # all but the last email in a multi-address replyto, and # drops all the display names. [tested 2016-03-10] # # To avoid those quirks, we provide a fully-formed Reply-To # in the custom headers, which makes it through intact. if emails: reply_to = ", ".join([email.address for email in emails]) self.data["headers"]["Reply-To"] = reply_to def set_extra_headers(self, headers): # SendGrid requires header values to be strings -- not integers. # We'll stringify ints and floats; anything else is the caller's responsibility. # (This field gets converted to json in self.serialize_data) self.data["headers"].update({ k: str(v) if isinstance(v, (int, float)) else v for k, v in headers.items() }) def set_text_body(self, body): self.data["text"] = body def set_html_body(self, body): if "html" in self.data: # second html body could show up through multiple alternatives, or html body + alternative self.unsupported_feature("multiple html parts") self.data["html"] = body def add_attachment(self, attachment): filename = attachment.name or "" if attachment.inline: filename = filename or attachment.cid # must have non-empty name for the cid matching content_field = "content[%s]" % filename self.data[content_field] = attachment.cid files_field = "files[%s]" % filename if files_field in self.files: # It's possible SendGrid could actually handle this case (needs testing), # but requests doesn't seem to accept a list of tuples for a files field. # (See the MailgunBackend version for a different approach that might work.) self.unsupported_feature( "multiple attachments with the same filename ('%s')" % filename if filename else "multiple unnamed attachments") self.files[files_field] = (filename, attachment.content, attachment.mimetype) def set_metadata(self, metadata): self.smtpapi['unique_args'] = metadata def set_send_at(self, send_at): # Backend has converted pretty much everything to # a datetime by here; SendGrid expects unix timestamp self.smtpapi["send_at"] = int(timestamp(send_at)) # strip microseconds def set_tags(self, tags): self.smtpapi["category"] = tags def add_filter(self, filter_name, setting, val): self.smtpapi.setdefault('filters', {})\ .setdefault(filter_name, {})\ .setdefault('settings', {})[setting] = val def set_track_clicks(self, track_clicks): self.add_filter('clicktrack', 'enable', int(track_clicks)) def set_track_opens(self, track_opens): # SendGrid's opentrack filter also supports a "replace" # parameter, which Anymail doesn't offer directly. # (You could add it through esp_extra.) self.add_filter('opentrack', 'enable', int(track_opens)) def set_template_id(self, template_id): self.add_filter('templates', 'enable', 1) self.add_filter('templates', 'template_id', template_id) def set_merge_data(self, merge_data): # Becomes smtpapi['sub'] in build_merge_data, after we know recipients and merge_field_format. self.merge_data = merge_data def set_merge_global_data(self, merge_global_data): # Becomes smtpapi['section'] in build_merge_data, after we know merge_field_format. self.merge_global_data = merge_global_data def set_esp_extra(self, extra): self.merge_field_format = extra.pop('merge_field_format', self.merge_field_format) self.data.update(extra)