Four golang scripts that provide ONVIF motion event polling and time/date setting. The scripts were created to allow the use of IP cameras without using a cloud service as a middle man between the user and the camera(s). The script main files are located in the cmd folder. To install the scripts into your local gopath run:
go install ./...
They will be placed inside the go/bin folder. Please make sure that GOPATH is defined beforehand.
The ONVIF standard exposed a set of services on a camera. One of them is the events service. Cameras with motion detection capabilities publish motion events over this service. There exist two models with which to get events from an ONVIF camera. One is polling - the client calls the device repeatedly and asks if any new events were created since the last call. The other is a subscription model where the client leaves a callback url and the camera uses this url to post notifications when a new event is created.
Polling is the most common feature implemented, and it is the one that is utilized here. The cameras I have used in the making of this script don't support subscription.
In order to use the polling script you must provide the mandatory arguments or the script will fail immediately. These include the base url of the camera, auth details and a slack configuration for the bot we will use to post notifications.
The script will then grab a snapshot from the camera and upload it to slack. The bot must have file upload privileges. There are more details in this guide here.
After that we can use the compiled native executable. Example:
onvif-motion-poll -a my-camera-url:1234 -u admin -p nimda -n garden -t 30 -b xoxb-slack-bot-token -c slack-channel-id
With this command the script will keep running continuously and polling the camera. After it finds a motion event, it will post to the slack url specified and identify the camera as "garden".
The second script deals with another problem when opting to use these cameras without a cloud provider - time synchronization. If cut off from access to the cloud, the cameras' system clock quickly falls out of sync with the world clock and is unable to contact an NTP server in order to correct itself. This script will continue updating the system clock with the local time of the server in which the script is running in regular intervals. Even with the low-cost nature of the clocks in these cameras, it is enough to maintain a sufficiently low drift for most surveillance purposes.
It requires four arguments for usage - the url and port (one string, seperated by semicolon), the username, the password and the interval time expressed in minutes as an integer. After interval expires, the time is set again.
Example:
onvif-set-time -a my-camera-url:1234 -u admin -p nimda -t 1
As with the previous script, this one keeps running and will post the current local time of the server to the camera, thereby synchronizing its system clock with the servers.
The third script will move the camera to a predefined ptz preset. The purpose of this script is to counter tampering and accidental camera misalignment due to power outages. Besides the authentication details, this script accepts the ptz preset name and the onvif profile name.
Example:
onvif-goto-preset -a my-camera-url:1234 -u admin -p nimda -t 1 -l 001 -r 000
The fourth script will record a ptz preset for the current position of the camera. It requires the authentication details, the preset name and, optionally, the onvif profile name.
Example:
onvif-set-preset -a my-camera-url:1234 -u admin -p nimda -l 003 -r 000
This script will run an onvif discovery broadcast on the interface specifed in the entry parameter. The interface must be specified by name. You cannot use a CIDR address to define it. If you are running this over Wireguard, it won't work as Wireguard does not support broadcasting.
Example:
onvif-discover-all -i wlo1
The command will output the number of discovered devices along with their IP addresses.
Please check the services folder for examples of what a systemd service template should look like if you choose to run
motion-poll or set-time as a service. By using environment files and templating, the user can handle multiple cameras
with only one service file.
For example, I will define my environment file hallway.env and place it in the configuration folder.
In order to run motion-poll as a service I will execute the following command:
systemctl start motion@hallway
This will use the [email protected] file and take all the relevant variables from the hallway.env file.
If I want the service to restart when the server restarts I need to enable it.
systemctl enable motion@hallway
The commands are the same as when running any other systemd service.
A Makefile is provided in the project root that will make a system-wide install of the go binaries once compiled. It will then use the provided service templates to create systemd services for every compiled command and place it in a config folder that the user can specify.
The user can then place .env files into the config folder and run systemctl to start any of the command services with
the name of the environment file. Be sure to enable any such services if you want them to run on restart!