grafana/pkg/services/ngalert/api/test-data/test-receiver.json

{
    "grafana_managed_receiver": {
        "uid": "alertmanager UID",
        "name": "an alert manager receiver",
        "type": "prometheus-alertmanager",
        "isDefault": false,
        "sendReminder": false,
        "disableResolveMessage": false,
        "frequency": "5m",
        "settings": {
            "autoResolve": true,
            "basicAuthUser": "user",
            "httpMethod": "POST",
            "severity": "critical",
            "uploadImage": false,
            "url": "http://localhost:9093"
        },
        "secureSettings": {
            "basicAuthPassword": "<basicAuthPassword>"
        }
    }
}