Keep alive client for the Kahu service.
KeKahu is a client service for the Kahu API that manages hosts on our experimental test bed. KeKahu's primary role is to send a keep-alive heartbeat to Kahu at a routine interval. KeKahu also provides DDNS by using an public IP lookup and posting that IP address to Kahu. Finally KeKahu can be used to synchronize peers and access the Kahu API in a meaningful way.
As long as you have go version 1.10 or later installed you can get and install KeKahu as follows:
$ go get github.com/bbengfort/kekahu/...
This command will build and install the kekahu binary in $GOBIN. In order for the command to be used with systemd, however, you must install it into a system path such as /usr/local/bin. I recommend using a symlink to make sure that the latest binary is used as follows:
$ sudo ln -s $GOBIN/kekahu /usr/local/bin/kekahu
Now that KeKahu is installed you can see its commands and options:
$ kekahu --help
Most of KeKahu is configured through the environment, though command line options can be specified. A .env file can be used for local use or development. Ensure the following environmental variables are set:
$KEKAHU_API_KEY: the Kahu API key for this machine$KEKAHU_URL(optional): url of the Kahu API$KEKAHU_INTERVAL(optional): interval between heartbeats
Further configuration can be specified by a JSON, YAML, or TOML file in either /etc/kekahu.json or ~/.kekahu.json (with the appropriate extension). An example configuration is as follows:
{
"interval": "20s",
"api_key": "mysupersecretkey",
"url": "https://kahu.io",
"verbosity": 2,
"peers_path": "peers.json",
"api_timeout": "5s",
"ping_timeout": "10s"
}Note that KeKahu won't run without an API key.
Once the configuration is set, you can use the kekahu application. For example, to synchronize network peers:
$ kekahu sync
Kekahu is configured to be managed by systemd on Linux systems. To get started create a file in /etc/systemd/system/kekahu.service as follows:
[Unit]
Description=KeKahu Service
Documentation=https://github.com/bbengfort/kekahu
[Service]
Type=simple
Environment=KEKAHU_API_KEY=mysupersecretkey
ExecStart=/usr/local/bin/kekahu run
Restart=on-abort
[Install]
WantedBy=multi-user.target
Now reload the services and enable the kekahu service:
$ sudo systemctl enable kekahu
$ sudo systemctl daemon-reload
The service can be managed with the start, stop, reload, and status commands as follows:
$ sudo systemctl start kekahu
You can check the status of the service to see if it started correctly, or use kekahu directly to check the status. In order to view the log files use the following command:
$ sudo journalctl -u kekahu
This should show everything written to stdout and stderr from the application.
We can also run kekahu as a user-agent on OS X - meaning that it will only run while the user is logged in. Create a file called ~/Library/LaunchAgents/com.bengfort.kekahu.plist and add the following configuration:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>Label</key>
<string>com.bengfort.kekahu</string>
<key>ProgramArguments</key>
<array>
<string>/usr/local/bin/kekahu</string>
<string>start</string>
</array>
<key>RunAtLoad</key>
<true/>
<key>EnvironmentVariables</key>
<dict>
<key>KEKAHU_API_KEY</key>
<string>mykey</string>
</dict>
<key>StandardOutPath</key>
<string>/tmp/kekahu.log</string>
<key>StandardErrorPath</key>
<string>/tmp/kekahu.err</string>
</dict>
</plist>
React
Typescript
Django
Laravel
Facebook
Microsoft
Google
Alibaba
D3
Tencent