A simple java program that can start 1 or more NATS Servers and then add chaos, by taking one of them down on a delay and bringing it back up after a downtime.
The project builds an Uber Jar that contains the compiled code for the Chaos Runner and the Nats Server Runner. You can get this jar in 2 ways.
-
Download the release: chaos-runner-0.0.3-uber.jar
-
Build from the source. Get the entire chaos-runner source from this Orbit repo, and from the chaos-runner project directory and run
gradle uberJarThe Uber Jarchaos-runner-0.0.3-SNAPSHOT-uber.jarwill appear in thebuild/libs/directory (relative to thechaos-runnerproject directory.)
| Argument | Description | Default |
|---|---|---|
--servers <1, 3 or 5> |
Number of servers. Accepts 1, 3 or 5 | 3 |
--delay <millis> |
Delay to bring down a server, starting when all servers are up. | 5000 |
--initial <millis> |
The first delay. Gives time to start your test program and run setup. | 30000 |
--down <millis> |
Delay to bring a server up once it is brought down. | 5000 |
--cname <name> |
Cluster name. Ignored for 1 server. | "cluster" |
--prefix <name> |
Prefix to use for the server name. Used in it's entirety for 1 server | "server" |
--dir <path> |
The working dir. Used as the parent dir for JetStream storage directories. | system temp |
--nojs |
Do not run the server with JetStream. JetStream is on by default. | JetStream |
--random |
Take the servers down randomly. Default is Round Robin. | Round Robin |
--port |
The starting server port. | 4222 |
--listen |
The starting listen port for clusters. | 4232 |
--monitor |
The starting monitor port. Use 0 for no monitor | 4282 |
Given any starting port, the system automatically figures the ports for the other nodes. For 1 node, the port and listen are used directly. For 3 or 5 nodes used for the first server, each server port is 1 more than the last. Make sure that starting and listen won't overlap. So for example, for 3 servers...
- If the starting server port is 4222, the other ports are 4223 and 4224.
- If the listen port is 4232, the other listen ports are 4232 and 4233
java -cp <Path-To>/<Jar-Name> io.synadia.chaos.ChaosRunner --delay 4000 --initial 10000 --cname mycluster --prefix myserver
java -cp <Path-To>/<Jar-Name> io.synadia.chaos.ChaosRunner --servers 1 --delay 4000 --initial 10000
1.If you downloaded the Uber Jar release:
- the
<Path-To>will be wherever you stored the file. - The
<Jar-Name>will bechaos-runner-0.0.3-uber.jar.
2. If you build it yourself:
- the
<Path-To>will be relative to thechaos-runnerdirectory inbuild/libs - the
<Jar-Name>will bechaos-runner-0.0.3-SNAPSHOT-uber.jar.
Alternatively you can run a program like the ChaosRunnerExample from an ide.
You can a download zip file containing a Windows executable chaos-runner.exe from the release page,
chaos-runner-003-windows-exe.zip
-or-
You can use GraalVM native-image to create a native executable for your platform. This assumes you've installed graalvm. You may need to specify the full path to the native-image.cmd (or your platform equivalent) if not already in your path.
> native-image.cmd --install-exit-handlers -cp <Path-To>\chaos-runner-0.0.3-uber.jar io.synadia.chaos.ChaosRunner chaos-runner
> chaos-runner.exe --servers 1 --delay 4000 --initial 10000
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