3. History logging

The history logging configuration controls the integration with Elasticsearch and the MTA, this enables users to for example release messages from quarantine and interact with the Halon queue directly.

To enable history logging there are some steps that need to be completed which are outlined below.

3.1. Install Elasticsearch

Instructions for how to install Elasticsearch can be found here.

3.2. Import an index template

Import one of the index templates below (Delivery attempts or Transactions) into Elasticsearch. The differences between these index templates are described in each section.

3.2.1. Delivery attempts

This template will log all delivery attempts and the same message may appear multiple times, once for each delivery attempt. For this template you should set the value for servers[].history.elasticsearch.index to halon-delivery-attempts in msui.yaml.

$ curl -k -X PUT -H "Content-Type: application/json" -d @/opt/halon/web/share/history/elasticsearch/delivery-attempts/halon_timeseries_policy.json http://elastic:[email protected]:9200/_ilm/policy/halon-timeseries-policy
$ curl -k -X PUT -H "Content-Type: application/json" -d @/opt/halon/web/share/history/elasticsearch/delivery-attempts/halon_delivery_attempts.json http://elastic:[email protected]:9200/_index_template/halon-delivery-attempts

3.2.2. Transactions

This template will log all transactions and update the state for them instead of creating a new log entry after each delivery attempt. For this template you should set the value for servers[].history.elasticsearch.index to halon-transactions-* in msui.yaml.

$ curl -k -X PUT -H "Content-Type: application/json" -d @/opt/halon/web/share/history/elasticsearch/transactions/halon_transactions.json http://elastic:[email protected]:9200/_index_template/halon-transactions

When using the transactions template you also need to periodically remove old indices in Elasticsearch, you can use Elasticsearch’s Curator CLI as a cron job. This sample configuration will remove indices older than 120 days based on the index and date syntax (e.g. halon-transactions-%Y-%m-%d).

Curator configuration ~/.curator/curator.yml sample file:

elasticsearch:
  client:
    hosts:
      - http://127.0.0.1:9200
    ca_certs:
    client_cert:
    client_key:
    verify_certs: False
    request_timeout: 30
  other_settings:
    username: elastic
    password: elastic
    master_only: False
logging:
  loglevel: INFO
  logfile:
  logformat: default
  blacklist: ['elastic_transport', 'urllib3']

Curator action ~/.curator/delete_indices.yml sample file:

actions:
  1:
    action: delete_indices
    description: >-
      Delete indices older than 120 days (based on index name)
    options:
      ignore_empty_list: True
      disable_action: False
    filters:
    - filtertype: pattern
      kind: prefix
      value: halon-transactions-
    - filtertype: age
      source: name
      direction: older
      timestring: '%Y-%m-%d'
      unit: days
      unit_count: 120

Run the action file with this command:

$ curator delete_indices.yml

3.3. Elasticsearch configuration

Once Elasticsearch is installed and the selected index template has been added, the settings must be configured to connect MSUI:

Copy one of the following files to /etc/halon/ (depending on the index template used in the previous step):

For transactions logging

# cp /opt/halon/msui/share/examples/msui-history-transactions.yaml /etc/halon/msui-history.yaml

For delivery attempts logging

# cp /opt/halon/msui/share/examples/msui-history-delivery-attempts.yaml /etc/halon/msui-history.yaml

Configure the Elasticsearch directives in the /etc/halon/msui.yaml configuration file:

servers:
  - [...]
    history:
      elasticsearch:
        index: 'halon-transactions-*'    # or 'halon-delivery-attempts'
        nodes:
          - url: https://elasticsearch:9200
        auth:
          username: elastic
          password: badpassword

Configure the MTA directives in the /etc/halon/msui.yaml configuration file:

servers:
  - [...]
    history:
      mta:
        nodes:
          - id: "hostname"
            url: http://smtpd:8080
            apikey: badsecret
            auth:
              username: admin
              password: admin