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Certain actions on the website trigger events that are handed to a RabbitMQ queueing server. These events and their contents are described here.

### Delivery mode ###
All events that are sent to the queue MUST be sent with '''delivery_mode = 2''' (persistent messages).

### Exchange name ###
All events are sent to the exchange '''extensionschoolevents'''

### Mail events ###

Mail is sent through the queue server in order to accomplish asynchronous mail sending (keep the webserver from blocking).

A mail event is identified by the routing key '''mail.sending'''

The body of a mail event consists of a JSON-encoded dictionary of the following form:

{{{
#!py
{
  'from_email': 'sender@my.domain',
  'recipient_list': [ 'recipient1@gmail.com', 'recipient2@hotmail.com' ],
  'subject': 'The subject line for this message',
  'message': 'A multi-line string holding the text version of this message',
  'html_message': 'A multi-line string holding the html-version of this message',
}
}}}

The '''html_message''' field is optional.

Example of an e-mail event:

{{{
#!py
import pika
import json

credentials = pika.PlainCredentials(SETTINGS.queueuser, SETTINGS.queuepassword)
connection = pika.BlockingConnection(pika.ConnectionParameters(
    host=SETTINGS.queuehost,credentials=credentials))
channel = connection.channel()
message = {
  'from_email': 'sender@my.domain',
  'recipient_list': [ 'recipient1@gmail.com', 'recipient2@hotmail.com' ],
  'subject': 'The subject line for this message',
  'message': 'A multi-line string holding the text version of this message',
  'html_message': 'A multi-line string holding the html-version of this message',
}
channel.basic_publish(
  exchange='extensionschoolevents',
  routing_key='mail.sending',
  body=json.dumps(message),
  properties=pika.BasicProperties(delivery_mode=2),
)
}}}

### Learner events ###

#### Add ####

This event must be sent when a new learner has registered. At this moment the learner MUST also have provided a password for his registration.

The routing key for this event is '''learner.add'''

The body of a learner.add event consists of a JSON-encoded dictionary of the following object:
{{{
{
  'learner': {
    'id': 15,
    'email': 'a.g.degroot@hotmail.com',
    'userlevel': 1,
    'newslettersubscription': false,
    'surname': 'Groot',
    'firstname': 'Anne',
    'nameprefix': 'de',
    'initials': 'A.G.',
    'gender': 'Female',          
  }
  'password': 'plaintext password for this learner'
}
}}}

The 'learner' key holds an encoding of the django-object from learners.models

Example of a '''learner.add''' event:


{{{
#!py
import pika
import jsonpickle

credentials = pika.PlainCredentials(SETTINGS.queueuser, SETTINGS.queuepassword)
connection = pika.BlockingConnection(pika.ConnectionParameters(
    host=SETTINGS.queuehost,credentials=credentials))
channel = connection.channel()
learner = learners.models.Learner.objects.get(id=learnerid)
message = {
  'learners': learner,
  'password': learnerpassword,
}
channel.basic_publish(
  exchange='extensionschoolevents',
  routing_key='learner.add',
  body=jsonpickle.encode(message),
  properties=pika.BasicProperties(delivery_mode=2),
)
}}}

#### Update ####

This event must be sent when a new learner has registered. At this moment the learner MUST also have provided a password for his registration.

The routing key for this event is '''learner.update'''

The body of a learner.add event consists of a JSON-encoded dictionary of the following object:
{{{
{
  'learner': {
    'id': 15,
    'email': 'a.g.degroot@hotmail.com',
    'userlevel': 1,
    'newslettersubscription': false,
    'surname': 'Groot',
    'firstname': 'Anne',
    'nameprefix': 'de',
    'initials': 'A.G.',
    'gender': 'Female',          
  }
  'password': 'plaintext password for this learner'
}
}}}

The 'learner' key holds an encoding of the django-object from learners.models

The 'password' key is optional and should only be filled in case of a password change.

Example of a '''learner.update''' event:


{{{
#!py
import pika
import jsonpickle

credentials = pika.PlainCredentials(SETTINGS.queueuser, SETTINGS.queuepassword)
connection = pika.BlockingConnection(pika.ConnectionParameters(
    host=SETTINGS.queuehost,credentials=credentials))
channel = connection.channel()
learner = learners.models.Learner.objects.get(id=learnerid)
message = {
  'learners': learner,
  'password': learnerpassword,
}
channel.basic_publish(
  exchange='extensionschoolevents',
  routing_key='learner.update',
  body=jsonpickle.encode(message),
  properties=pika.BasicProperties(delivery_mode=2),
)
}}}