eventmaster

There are lots of events that happen in production such as deploys, service restarts, scale-up operations, etc. Right now these events happen, but we have no centralized place to track them -- which means we have no centralized place to search them. This project implements a service that:

• Creating an event store
• API for sending/firing events
• Potential integrations into other services for searching etc. (e.g. grafana annotations)
• Working with other pieces of infrastructure to expose meaningful events

Setup

Dependencies

• Go tool (tested at v1.16)
• Either one of the following
  • Postgres (preferred), or
  • Cassandra (deprecated)

Get Code

$ git clone \
    [email protected]:wish/eventmaster.git \
    $GOPATH/src/github.com/wish/eventmaster

Building

Dependencies are currently fetched using Go Modules. These are set up as dependencies to the default make target, so running:

make

will emit $GOPATH/bin/eventmaster after fetching and compiling dependencies.

Running

After running make eventmaster can be called directly:

$ $GOPATH/bin/eventmaster

Giving no flags eventmaster runs with sane option.

Configuration

Various aspects of eventmaster can be controlled through a collection of flags and options in a json config file. This will be consolidated when issue #32 is resolved.

The config provided in etc/eventmaster.json encodes the default values assumed by eventmaster if run without specifying a config file (-c). If these settings do not work for your service, please modify etc/eventmaster.json to specify values such as the addresses of the Cassandra cluster along with other database options.

Of note if "cassandra_config":"service_name" is non-empty then eventmaster currently uses discovery to find the IPs of the Cassandra cluster.

For example the port of the eventmaster server can be configured using the --port option, and if an alternate cassandra address needs to be specified adjust a eventmaster.json file and specify that it is used by providing the -c flag.

Open the eventmaster UI in your browser (default: http://localhost:50052). The UI can be used to create and query topics, data centers, and events.

Database Connection

Eventmaster currently supports two database backends: Postgres (preferred) and Cassandra (deprecated). The choice of database needs to supplied in the data_store field of the config file.

To connect to a Postgres database, serveral fields have to be set in the configration file. This includes:

• data_store: your choice of database. Set to postgres to connect to a postgres database

• postgres_config: object containing postgres configs

  • addr: address of the postgres database
  • port: port of the postgres database
  • database: the name of the database
  • username: the username of the user with necessary permission to connect/read/write, and
  • password: the password of the user (ommited if Vault integration is turned on)
  • max_db_conn_count: maximum database connections allowed (defaulted to be 128)

  Additionally, you may choose to toggle integration with HasiCorp Vault. This allows Eventmaster to obtain database password from Vault instead of leaving them as plain-text in the filesystem. Only v2 is supported currently. To do so, set the following fields:

  • vault: object containing Vault config
    • enabled: set to true to enable Vault integration
    • addr: API endpoint of Vault
    • token: token used to connect to Vault
    • path: path to the password

Although no longer recommended, you can connect to a Cassandra database by setting the following fields:

• data_store: set to cassandra to connect to a c* database

  • addrs: array of C* database addresses
  • keyspace: name of the keyspace you wish to use
  • consistency: consistency level setting, default to be one,
  • timeout: connection timeout

  To connect to a Cassandra database over TLS, several fields have to be set in the configration file. This includes:

  • secured: Setting this field to true triggers TLS
  • ca_path: The path to the CA cert file
  • port: If different than default native protocol clients (port 9042)
  • username
  • password

An example of the config file can be found here

Database Setup

Execute schema.sql or schema.cql from the schema directory on your database cluster. This will set up the tables needed.

Tests

Tests can be run (using the go tool) by calling:

$ make test

Adding annotations to a Grafana dashboard

This is documented in the documentation subdirectory

REST API

This is documented in the documentation subdirectory.