MongooseIM core component
It is based on gen_server & ETS table w. public read access. This module is local for the node, it does not implement any sync across the nodes in a cluster. This component is responsible for dynamic routing, it is always started by MIM even if there is no support of dynamic domain names configured.
It provides the following interfaces:
- Init - accepts the list of initial domain/host_type pairs provided in
config file, and the list of host_types that can be used for dynamic insertion.
Any of these lists can be empty, initial list of domain/host_type pairs can
have some unique host_types not mentioned in the host_types list.
The component is initialised by the main MIM supervisor.
- Insert - adding new domain/host_type pair.
This function is idempotent. It returns success on an attempt to insert the existing data,
but fails if ETS already has the domain name associated with another host type.
- Remove - This function is idempotent. It deletes existing
It is impossible to delete domain/host_type pairs specified on init
of the component.
- Get host type by domain.
- Get all domains configured for the host_type.
- Get the list of the host_types provided during initialisation.
- Default (initial) domains are static.
- Disabled or deleted domains are not in
- Static domains are non-mutable.
- Static domains are not replicated.
- Static domains has priority above DB domains.
As described in Services.
Implements the service behaviour.
This service provides an interface for dynamic management of domain names. It has persistent storage (RDBMS) where it stores information about domain names. This service ensures synchronization of dynamically managed domain names across different nodes in the cluster.
The minimal set of information associated with domain name is this:
- Host type
- Status (enabled/disabled)
This service provides the following interfaces:
- Init - on init all the “enabled” domain names from the persistent storage is added to the core MIM component described above.
- Add domain name (w/ host type) - This function is idempotent. An added domain is always “enabled” by default - it must be added in the core MIM component described in the previous section. If it’s successfully enabled than Information about the domain name is added into persistent storage and distributed across all the nodes in the cluster.
- Disabling/Enabling domain name - This function is idempotent. The status of the existing domain is always changed on successful call. If domain name is enabled, then it is added in the core MIM component. On disabling domain name is deleted from the core MIM component. Change of the status is distributed across all the nodes in the cluster.
- Remove the domain name - This function is idempotent. Domain name is deleted from the core MIM component (if required) and from the DB. This action is distributed across all the nodes in the cluster.
In case of any issues (domain name is already configured with another host_type or host_type is not supported), errors are logged.
The database schema contains two tables:
domain_settings- one record per domain. Maps
domain_events- the log of changes. The only reason it exists is that we can track updates in the
domain_settingsand get apply updates across different nodes. The old events are eventually deleted from the table. Removal is triggered by all nodes of MongooseIM, that have the service configured.
service_domain_db module does two tasks:
- Initially downloads domains from
domain_settingstable, using sorting by id.
- Waits for
check_for_updatesmessage and updates core component, depending on records in the
id field to sort records when paginating.
You cannot delete domains with unknown host-type. Configure host-type first to delete such domains.
Modules which store data in RDBMS and support dynamic domains will remove all persistent data associated with a domain when its removal is requested.
This is not the case for NoSQL databases or Mnesia.
Because of that, we recommend using RDBMS with dynamic domains.
Please note, that
mod_auth_token is the only exception for now and does not remove data from RDBMS when removing a domain.
Described in the
Command Line Interface
You can manage the domains with the
mongooseimctl command. Some examples are provided below:
./mongooseimctl domain to get more information about all supported operations.
You can manage domains with one of our API's: