Eventhistory Service Configuration

Introduction

The Infinite Scale eventhistory service consumes all events from the configured event system like NATS, stores them and allows other services to retrieve them via an event ID.

Prerequisites

Running the eventhistory service without an event sytem like NATS is not possible.

Consuming

The eventhistory services consumes all events from the configured event sytem.

Storing

The eventhistory service stores each consumed event via the configured store in EVENTHISTORY_STORE_TYPE. Possible stores are:

Store Type Description

mem

Basic in-memory store and the default.

ocmem

Advanced in-memory store allowing max size.

Redis

Stores data in a configured Redis cluster.

etcd

Stores data in a configured etcd cluster.

nats-js

Stores data using the key-value-store feature of NATS JetStream.

noop

Stores nothing. Useful for testing. Not recommended in productive environments.

  1. Note that in-memory stores are by nature not reboot persistent.

  2. Though usually not necessary, a database name and a database table can be configured for event stores if the event store supports this. Generally, this does not apply to stores of type in-memory. These settings are blank by default which means that the standard settings of the configured store applies.

  3. Events stay in the store for 2 weeks by default. Use EVENTHISTORY_RECORD_EXPIRY to adjust this value.

  4. The eventhistory service can be scaled if it’s not using in-memory stores and the stores are configured identically over all instances.

Retrieving

Other services can call the eventhistory service via a gRPC call to retrieve events. The request must contain the event ID that should be retrieved.

Configuration

Environment Variables

The eventhistory service is configured via the following environment variables:

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Environment variables for the eventhistory service
Name Type Default Value Description

OCIS_LOG_LEVEL
EVENTHISTORY_LOG_LEVEL

string

The log level. Valid values are: "panic", "fatal", "error", "warn", "info", "debug", "trace".

OCIS_LOG_PRETTY
EVENTHISTORY_LOG_PRETTY

bool

false

Activates pretty log output.

OCIS_LOG_COLOR
EVENTHISTORY_LOG_COLOR

bool

false

Activates colorized log output.

OCIS_LOG_FILE
EVENTHISTORY_LOG_FILE

string

The path to the log file. Activates logging to this file if set.

EVENTHISTORY_DEBUG_ADDR

string

Bind address of the debug server, where metrics, health, config and debug endpoints will be exposed.

EVENTHISTORY_DEBUG_TOKEN

string

Token to secure the metrics endpoint.

EVENTHISTORY_DEBUG_PPROF

bool

false

Enables pprof, which can be used for profiling.

EVENTHISTORY_DEBUG_ZPAGES

bool

false

Enables zpages, which can be used for collecting and viewing in-memory traces.

EVENTHISTORY_GRPC_ADDR

string

127.0.0.1:0

The bind address of the GRPC service.

EVENTHISTORY_EVENTS_ENDPOINT

string

127.0.0.1:9233

The address of the event system. The event system is the message queuing service. It is used as message broker for the microservice architecture.

EVENTHISTORY_EVENTS_CLUSTER

string

ocis-cluster

The clusterID of the event system. The event system is the message queuing service. It is used as message broker for the microservice architecture. Mandatory when using NATS as event system.

OCIS_INSECURE
EVENTHISTORY_EVENTS_TLS_INSECURE

bool

false

Whether to verify the server TLS certificates.

EVENTHISTORY_EVENTS_TLS_ROOT_CA_CERTIFICATE

string

The root CA certificate used to validate the server’s TLS certificate. If provided NOTIFICATIONS_EVENTS_TLS_INSECURE will be seen as false.

OCIS_EVENTS_ENABLE_TLS
EVENTHISTORY_EVENTS_ENABLE_TLS

bool

false

Enable TLS for the connection to the events broker. The events broker is the ocis service which receives and delivers events between the services..

OCIS_PERSISTENT_STORE
EVENTHISTORY_STORE
OCIS_PERSISTENT_STORE_TYPE
EVENTHISTORY_STORE_TYPE

string

memory

The type of the eventhistory store. Supported values are: 'memory', 'ocmem', 'etcd', 'redis', 'redis-sentinel', 'nats-js', 'noop'. See the text description for details.

OCIS_PERSISTENT_STORE_NODES
EVENTHISTORY_STORE_ADDRESSES

[]string

[]

A comma separated list of nodes to access the configured store. This has no effect when 'in-memory' stores are configured. Note that the behaviour how nodes are used is dependent on the library of the configured store.

EVENTHISTORY_STORE_DATABASE

string

eventhistory

The database name the configured store should use.

EVENTHISTORY_STORE_TABLE

string

events

The database table the store should use.

EVENTHISTORY_RECORD_EXPIRY

Duration

336h0m0s

Time to live for events in the store. The duration can be set as number followed by a unit identifier like s, m or h. Defaults to '336h' (2 weeks).

EVENTHISTORY_STORE_SIZE

int

0

The maximum quantity of items in the store. Only applies when store type 'ocmem' is configured. Defaults to 512.

YAML Example

Note that the filename shown below has been chosen on purpose.
See the Configuration File Naming for details when setting up your own configuration.

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# Autogenerated
# Filename: eventhistory-config-example.yaml

log:
  level: ""
  pretty: false
  color: false
  file: ""
debug:
  addr: ""
  token: ""
  pprof: false
  zpages: false
grpc:
  addr: 127.0.0.1:0
  tls: null
grpc_client_tls: null
events:
  endpoint: 127.0.0.1:9233
  cluster: ocis-cluster
  tls_insecure: false
  tls_root_ca_certificate: ""
  enable_tls: false
store:
  store: memory
  nodes: []
  database: eventhistory
  table: events
  record_expiry: 336h0m0s
  size: 0