EventLog Microservice

This is a system event logging microservice from Pip.Services library.
It logs important system events like starts and stops of servers,
upgrades to a new version, fatal system errors or key business transactions.

The microservice currently supports the following deployment options:
* Deployment platforms: Standalone Process, Seneca Plugin
* External APIs: HTTP/REST, Seneca
* Persistence: Memory, Flat Files, MongoDB

This microservice has no dependencies on other microservices.

Quick Links:

* Download Links
* Development Guide
* Configuration Guide
* Deployment Guide
* Client SDKs
- Node.js SDK
* Communication Protocols
- HTTP Version 1
- Seneca Version 1

Contract

Logical contract of the microservice is presented below. For physical implementation (HTTP/REST, Thrift, Seneca, Lambda, etc.),
please, refer to documentation of the specific protocol.

``typescript
class SystemEventV1 implements IStringIdentifiable {
public id: string;
public time: Date;
public correlation_id: string;
public source: string;
public type: string;
public severity: EventLogSeverityV1;
public message: string;
public details: StringValueMap;

}

class EventLogTypeV1
{
public static readonly Restart: string = "restart";
public static readonly Failure: string = "failure";
public static readonly Warning: string = "warning";
public static readonly Transaction: string = "transaction";
public static readonly Other: string = "other";
}

enum EventLogSeverityV1
{
Critical = 0,
Important = 500,
Informational = 1000
}

interface IEventLogV1 {
getEvents(correlationId: string, filter: FilterParams, paging: PagingParams): Promise>;

logEvent(correlationId: string, event: SystemEventV1): Promise;
}
`

Download

Right now the only way to get the microservice is to check it out directly from github repository
`bash
git clone git@github.com:pip-services-infrastructure2/service-eventlog-node.git
`

Pip.Service team is working to implement packaging and make stable releases available for your
as zip downloadable archieves.

Run

Add config.json file to the root of the microservice folder and set configuration parameters.
As the starting point you can use example configuration from config.example.yml file.

Example of microservice configuration
`yaml
- descriptor: "pip-services-container:container-info:default:default:1.0"
name: "service-eventlog"
description: "EventLog microservice"

- descriptor: "pip-services-commons:logger:console:default:1.0"
level: "trace"

- descriptor: "service-eventlog:persistence:file:default:1.0"
path: "./data/eventlog.json"

- descriptor: "service-eventlog:controller:default:default:1.0"

- descriptor: "service-eventlog:service:http:default:1.0"
connection:
protocol: "http"
host: "0.0.0.0"
port: 8080
`

For more information on the microservice configuration see Configuration Guide.

Start the microservice using the command:
`bash
node run
`

Use

The easiest way to work with the microservice is to use client SDK.
The complete list of available client SDKs for different languages is listed in the Quick Links

If you use Node.js then you should add dependency to the client SDK into package.json file of your project
`javascript
{
...
dependencies: {
...
"client-eventlog-node": "^1.0.*"
...
}
}
`

Inside your code get the reference to the client SDK
`javascript
var sdk = new require('client-eventlog-node');
`

Define client configuration parameters that match configuration of the microservice external API
`javascript
// Client configuration
var config = {
connection: {
protocol: 'http',
host: 'localhost',
port: 8080
}
};
`

Instantiate the client and open connection to the microservice
`javascript
// Create the client instance
var client = sdk.EventLogHttpClientV1(config);

// Connect to the microservice
try {
await client.open(null});
// Work with the microservice
...
} catch(err) {
console.error('Connection to the microservice failed');
console.error(err);
}

`

Now the client is ready to perform operations
`javascript
// Log system event
let event = await client.logEvent(
null,
{
type: 'restart',
source: 'server1',
message: 'Restarted server'
}
);
`

`javascript
var now = new Date();

// Get the list system events
let page = await client.getEvents(
null,
{
from_time: new Date(now.getTime() - 24 3600 1000),
to_time: now,
source: 'server1'
},
{
total: true,
skip: 0,
take: 10
}
);
``

Acknowledgements

This microservice was created and currently maintained by Sergey Seroukhov.