EaseAgent

An agent component for Java system.

EaseAgent

Overview

Easeagent is the underlying component that provides non-intrusive extensions to applications of the Java ecosystem.
Non-intrusive application extensions currently include data collection, such as tracing, metric and log collection in the APM application domain; it also includes control-panel extensions, such as redirection plugins, to provide the ability of dynamically modify configuration of the connecting back-end for supporting special scenarios, such as online stress testing in the production environment.
In addition, users can extend Easeagent in the form of plugins to support the non-intrusive needs of user-specific scenarios.

Purpose

EaseAgent can be a Java agent for APM(Application Performance Management) system.
EaseAgent collects the basic metrics and the service tracing logs, which is very helpful for performance analysis and troubleshooting.
EaseAgent is compatible with mainstream monitoring ecosystems, such as Kafka, ElasticSearch, Prometheus, Zipkin, etc.
EaseAgent majorly focuses on the Spring Boot development environments, but users can support any Java ecosystem applications through plugins.
Easeagent can support scenario-specific business requirements through the plugin mechanism, such as traffic redirection, traffic coloring, etc.

Principles

Safe to Java application/service.
Instrumenting a Java application in a non-intrusive way.
Lightweight and very low CPU, memory, and I/O resource usage.
Highly extensible, users can easily do extension through a simple and clear plugin interface.
Design for Micro-Service architecture, collecting the data from a service perspective.

Features

Easy to use. It is right out of the box for Metirc, Tracing and Logging collecting.
- Collecting Metric & Tracing Logs.
  - JDBC 4.0
  - HTTP Servlet、HTTP Filter
  - Spring Boot 2.2.x: WebClient 、 RestTemplate、FeignClient
  - RabbitMQ Client 5.x、 Kafka Client 2.4.x
  - Jedis 3.5.x、 Lettuce 5.3.x
- Collecting Access Logs.
  - HTTP Servlet、HTTP Filter
  - Spring Cloud Gateway
- Instrumenting the traceId and spanId into user application logging automatically
- Supplying the health check endpoint
- Supplying the readiness check endpoint for SpringBoot2.2.x
Easy to Extend
- Simple and clear Plugin Interface, creating a plugin as few as three classes.
- Extremely cleanly packaged Tracing and Metric API, with a small amount of code to achieve business support.
Standardization
- The tracing data format is fully compatible with the zipkin data format.
- Metric data format fully supports integration with Prometheus.

Architecture Diagram

Description

Plugin Framework in core module is base on Byte buddy technology.

Easeagent's plugin defines where (which classes and methods) to make enhancements by Points implementation and what to do at the point of enhancement by the implementations of Interceptor.
When the program invokes the enhanced method of class defined by Points, the unique index(uid) owned by the method will be used as a parameter to call the common interface of Agent Common Method Advice, which finds the Agent Interceptor Chain by the Unique Index and calls the before method of each Interceptor in the chain in order of priority.
Normally, both the Metric Interceptor and the Tracing Interceptor are in the agent interceptor chain and are called sequentially.
According to call the Metric API and Tracing API in interceptors, the Metric and Tracing information will be stored in MetricRegistry and Tracing.
The Reporter module will get information from MetricRegistry and Tracing and send it to Kafka.
The after method of each interceptor in the Agent Interceptor Chain will be invoked in the reverse order of the before invoked at last.
The tracing data can be send to kafka server or zipkin server, the metric data can be send to kafka server and pull by Prometheus server.

QuickStart

Download

Download easeagent.jar from releases releases.

$ curl -Lk https://github.com/megaease/easeagent/releases/download/{tag}/easeagent.jar -O

Build From Source

Download EaseAgent with git clone https://github.com/megaease/easeagent.git.

$ cd easeagent
$ mvn clean package

The ./build/target/easeagent-dep.jar is the agent jar with all the dependencies.

Windows platform user please make sure git core.autocrlf is set to false before git clone. You can use git config --global core.autocrlf false to modify core.autocrlf.

1. Get Configuration file

Extracting the default configuration file.

$ jar xf easeagent.jar agent.properties easeagent-log4j2.xml

2. Modify Configuration

Modify service name, default configuration is demo-service.

name=[app-name]

Modify kafka server config, default configuration is 127.0.0.1:9092. Both tracing data and metric data will be send to kafka server by default configuration.

observability.outputServer.bootstrapServer = [ip:port]

Modify output configuration, if you want to watch log information in console.

# metric output
observability.metrics.[xxxx].appendType=console

# tracings output to console
observability.tracings.output.target=system
observability.tracings.output.enabled=false

If you want to watch tracing information only in console, comment out the outputServer configuration and set target to 'system':

# observability.outputServer.bootstrapServer=127.0.0.1:9092
# observability.outputServer.timeout=10000
# observability.outputServer.enabled=true

observability.tracings.output.target=system

Sending tracing data to zipkin server

# [zipkin]: send data to zipkin server
# [system]: send data to kafka
observability.tracings.output.target=zipkin
observability.tracings.output.target.zipkinUrl=http://localhost:9411/api/v2/spans

3. Building the demo application and simple plugin.

$ git clone https://github.com/megaease/easeagent-test-demo.git
$ cd spring-web
$ mvn clean package

$ cd simple-plugin
$ mvn clean package

There is an agent.properties configuration file in the demo directory, which is configured to print all information to the console. If you want to print all information to console, then you can use this configuration file.

4. Copy simple plugin to `plugins` directory

There is a simple plugin which only for demonstrating the use of the plugin. The compiled simple plugin JAR package should be copy to the plugins directory located in EASE_AGENT_PATH, and if the directory is not exsist, it need to be created.

$ export EASE_AGENT_PATH=[Replace with agent path]
cp target/simple-plugin-1.0.jar $EASE_AGENT_PATH/plugins/

5. Run the demo application with EaseAgent.

# Open another console
$ export EASE_AGENT_PATH=[Replace with agent path]
$ java "-javaagent:${EASE_AGENT_PATH}/easeagent-dep.jar=${EASE_AGENT_PATH}/agent.properties" -Deaseagent.server.port=9900 -jar target/spring-web-1.0.jar

6. Integrate with Prometheus

Adding the following configuration in prometheus.yml

  - job_name: 'spring-web-service'
    static_configs:
      - targets: ['localhost:9900']
    metrics_path: "/prometheus/metrics"

Start Prometheus

$ ./prometheus --config.file=prometheus.yml

# Open another console, run curl to access the test url for several times.
$ curl -v http://127.0.0.1:18888/web_client

7. Test Data

Tracing
If the tracing data is send to console, there would be some tracing log in console like this:

[{"traceId":"5a8800b902703307","parentId":"84c4cba42fb92788","id":"fd00a1705c88cbb2","kind":"SERVER","name":"get","timestamp":1639493283759877,"duration":217545,"shared":true,"localEndpoint":{"serviceName":"demo-service","ipv4":"192.168.0.102"},"remoteEndpoint":{"ipv4":"127.0.0.1","port":55809},"tags":{"http.method":"GET","http.path":"/hello","http.route":"/hello","i":"ServerName.local"},"type":"log-tracing","service":"demo-service","system":"demo-system"},{"traceId":"5a8800b902703307","id":"5a8800b902703307","kind":"SERVER","name":"get","timestamp":1639493283753466,"duration":228827,"localEndpoint":{"serviceName":"demo-service","ipv4":"192.168.0.102"},"remoteEndpoint":{"ipv4":"127.0.0.1","port":55851},"tags":{"http.method":"GET","http.path":"/web_client","i":"ServerName.local"},"type":"log-tracing","service":"demo-service","system":"demo-system"}]

...

Metric
Open Browser to visit http://localhost:9090.

After visit more pages, open Prometheus manager http://localhost:9090, and search _00GET__web_client. You will see as following.

User Manual

For more information, please refer to the User Manual.

Plugin Development Guide

Refer to Plugin Development Guide.

Licenses

EaseAgent is licensed under the Apache License, Version 2.0. See LICENSE for the full license text.

pengjiejason/easeagent