firehol/netdata

// SPDX-License-Identifier: GPL-3.0-or-later

package nginxunit

import (
    "encoding/json"
    "errors"
    "fmt"
    "net/http"

    "github.com/netdata/netdata/go/plugins/plugin/go.d/pkg/stm"
    "github.com/netdata/netdata/go/plugins/plugin/go.d/pkg/web"
)

const (
    urlPathStatus = "/status"
)

// https://unit.nginx.org/statusapi/
type nuStatus struct {
    Connections *struct {
        Accepted int64 `json:"accepted" stm:"accepted"`
        Active   int64 `json:"active" stm:"active"`
        Idle     int64 `json:"idle" stm:"idle"`
        Closed   int64 `json:"closed" stm:"closed"`
    } `json:"connections" stm:"connections"`
    Requests struct {
        Total int64 `json:"total" stm:"total"`
    } `json:"requests" stm:"requests"`
}

func (n *NginxUnit) collect() (map[string]int64, error) {
    req, err := web.NewHTTPRequestWithPath(n.RequestConfig, urlPathStatus)
    if err != nil {
        return nil, fmt.Errorf("failed to create HTTP request to '%s': %v", n.URL, err)
    }

    var status nuStatus

    wc := web.DoHTTP(n.httpClient).OnNokCode(func(resp *http.Response) (bool, error) {
        var msg struct {
            Error string `json:"error"`
        }
        if json.NewDecoder(resp.Body).Decode(&msg) == nil && msg.Error != "" {
            return false, errors.New(msg.Error)
        }
        return false, nil
    })

    if err := wc.RequestJSON(req, &status); err != nil {
        return nil, err
    }

    if status.Connections == nil {
        return nil, errors.New("unexpected response: no connections available")
    }

    return stm.ToMap(status), nil
}