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.

Default Values

  • The eventhistory service listens on port 9174 by default.

Prerequisites

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

Consuming

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

Storing

The eventhistory service can use a configured store via the global OCIS_PERSISTENT_STORE environment variable.

Note that for each global environment variable, a service-based one might be available additionally. For precedences see Environment Variable Notes. Check the configuration section below. Supported stores are:

Store Type Description

memory

Basic in-memory store and the default.

redis-sentinel

Stores data in a configured Redis Sentinel cluster.

nats-js-kv

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

noop

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

ocmem

(deprecated) Advanced in-memory store allowing max size.

redis

(deprecated) Stores data in a configured Redis cluster.

etcd

(deprecated) Stores data in a configured etcd cluster.

nats-js

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

Other store types may work but are currently not supported.

The eventhistory service can only be scaled if not using the memory store and the stores are configured identically over all instances!
If you have used one of the deprecated stores of a former version, you should reconfigure to use one of the supported ones as the deprecated stores will be removed in a later version.
Store specific notes

  • When using redis-sentinel:
    The Redis master to use is configured via e.g. OCIS_PERSISTENT_STORE_NODES in the form of <sentinel-host>:<sentinel-port>/<redis-master> like 10.10.0.200:26379/mymaster.

  • When using nats-js-kv:

    • It is recommended to set OCIS_PERSISTENT_STORE_NODES to the same value as OCIS_EVENTS_ENDPOINT. That way the cache uses the same nats instance as the event bus.

    • Authentication can be added, if configured, via OCIS_CACHE_AUTH_USERNAME and OCIS_CACHE_AUTH_PASSWORD.

    • It is possible to set OCIS_CACHE_DISABLE_PERSISTENCE to instruct nats to not persist cache data on disc.

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.

Event Bus Configuration

The Infinite Scale event bus can be configured by a set of environment variables.

  • If you are using a binary installation as described in Minimal Bare Metal Deployment or Bare Metal with systemd, the address of the event bus OCIS_EVENTS_ENDPOINT is predefined as localhost address without the need for further configuration, but changeable on demand.

  • In case of an orchestrated installation like with Docker or Kubernetes, the event bus must be an external service for scalability like a Redis Sentinel cluster or a key-value-store NATS JetStream. Both named stores are supported and also used in Caching and Persistence. The store used is not part of the Infinite Scale installation and must be separately provided and configured.

  • Note that from a configuration point of view, caching and persistence are independent of the event bus configuration.

Note that for each global environment variable, a service-based one might be available additionally. For precedences see Environment Variable Notes. Check the configuration section below.

Without the aim of completeness, see the list of environment variables to configure the event bus:

Envvar Description

OCIS_EVENTS_ENDPOINT

The address of the event system.

OCIS_EVENTS_CLUSTER

The clusterID of the event system. Mandatory when using NATS as event system.

OCIS_EVENTS_ENABLE_TLS

Enable TLS for the connection to the events broker.

OCIS_INSECURE

Whether to verify the server TLS certificates.

OCIS_EVENTS_AUTH_USERNAME

The username to authenticate with the events broker.

OCIS_EVENTS_AUTH_PASSWORD

The password to authenticate with the events broker.

Configuration

Environment Variables

The eventhistory service is configured via the following environment variables. Read the Environment Variable Types documentation for important details.

  • 5.0.3

Environment variables for the eventhistory service
Name Type Default Value Description

OCIS_TRACING_ENABLED
EVENTHISTORY_TRACING_ENABLED

bool

false

Activates tracing.

OCIS_TRACING_TYPE
EVENTHISTORY_TRACING_TYPE

string

The type of tracing. Defaults to '', which is the same as 'jaeger'. Allowed tracing types are 'jaeger' and '' as of now.

OCIS_TRACING_ENDPOINT
EVENTHISTORY_TRACING_ENDPOINT

string

The endpoint of the tracing agent.

OCIS_TRACING_COLLECTOR
EVENTHISTORY_TRACING_COLLECTOR

string

The HTTP endpoint for sending spans directly to a collector, i.e. http://jaeger-collector:14268/api/traces. Only used if the tracing endpoint is unset.

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

127.0.0.1:9270

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.

OCIS_EVENTS_ENDPOINT
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.

OCIS_EVENTS_CLUSTER
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.

OCIS_EVENTS_TLS_ROOT_CA_CERTIFICATE
EVENTHISTORY_EVENTS_TLS_ROOT_CA_CERTIFICATE

string

The root CA certificate used to validate the server’s TLS certificate. Will be seen as empty if NOTIFICATIONS_EVENTS_TLS_INSECURE is provided.

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_EVENTS_AUTH_USERNAME
EVENTHISTORY_EVENTS_AUTH_USERNAME

string

The username to authenticate with the events broker. The events broker is the ocis service which receives and delivers events between the services.

OCIS_EVENTS_AUTH_PASSWORD
EVENTHISTORY_EVENTS_AUTH_PASSWORD

string

The password to authenticate with the events broker. The events broker is the ocis service which receives and delivers events between the services.

OCIS_PERSISTENT_STORE
EVENTHISTORY_STORE

string

memory

The type of the 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_NODES

[]string

[]

A list of nodes to access the configured store. This has no effect when 'memory' or 'ocmem' stores are configured. Note that the behaviour how nodes are used is dependent on the library of the configured store. See the Environment Variable Types description for more details.

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.

OCIS_PERSISTENT_STORE_TTL
EVENTHISTORY_STORE_TTL

Duration

336h0m0s

Time to live for events in the store. Defaults to '336h' (2 weeks). See the Environment Variable Types description for more details.

OCIS_PERSISTENT_STORE_SIZE
EVENTHISTORY_STORE_SIZE

int

0

The maximum quantity of items in the store. Only applies when store type 'ocmem' is configured. Defaults to 512 which is derived and used from the ocmem package though no explicit default was set.

OCIS_PERSISTENT_STORE_AUTH_USERNAME
EVENTHISTORY_STORE_AUTH_USERNAME

string

The username to authenticate with the store. Only applies when store type 'nats-js-kv' is configured.

OCIS_PERSISTENT_STORE_AUTH_PASSWORD
EVENTHISTORY_STORE_AUTH_PASSWORD

string

The password to authenticate with the store. Only applies when store type 'nats-js-kv' is configured.

YAML Example

  • 5.0.3

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

tracing:
  enabled: false
  type: ""
  endpoint: ""
  collector: ""
log:
  level: ""
  pretty: false
  color: false
  file: ""
debug:
  addr: 127.0.0.1:9270
  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
  username: ""
  password: ""
store:
  store: memory
  nodes: []
  database: eventhistory
  table: events
  ttl: 336h0m0s
  size: 0
  username: ""
  password: ""