netdata/netdata

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

package couchbase

import (
    "encoding/json"
    "fmt"
    "io"
    "net/http"
    "net/url"

    "github.com/netdata/netdata/go/go.d.plugin/agent/module"
    "github.com/netdata/netdata/go/go.d.plugin/pkg/web"
)

const (
    urlPathBucketsStats = "/pools/default/buckets"

    precision = 1000
)

func (cb *Couchbase) collect() (map[string]int64, error) {
    ms, err := cb.scrapeCouchbase()
    if err != nil {
        return nil, fmt.Errorf("error on scraping couchbase: %v", err)
    }
    if ms.empty() {
        return nil, nil
    }

    collected := make(map[string]int64)
    cb.collectBasicStats(collected, ms)

    return collected, nil
}

func (cb *Couchbase) collectBasicStats(collected map[string]int64, ms *cbMetrics) {
    for _, b := range ms.BucketsBasicStats {

        if !cb.collectedBuckets[b.Name] {
            cb.collectedBuckets[b.Name] = true
            cb.addBucketToCharts(b.Name)
        }

        bs := b.BasicStats
        collected[indexDimID(b.Name, "quota_percent_used")] = int64(bs.QuotaPercentUsed * precision)
        collected[indexDimID(b.Name, "ops_per_sec")] = int64(bs.OpsPerSec * precision)
        collected[indexDimID(b.Name, "disk_fetches")] = int64(bs.DiskFetches)
        collected[indexDimID(b.Name, "item_count")] = int64(bs.ItemCount)
        collected[indexDimID(b.Name, "disk_used")] = int64(bs.DiskUsed)
        collected[indexDimID(b.Name, "data_used")] = int64(bs.DataUsed)
        collected[indexDimID(b.Name, "mem_used")] = int64(bs.MemUsed)
        collected[indexDimID(b.Name, "vb_active_num_non_resident")] = int64(bs.VbActiveNumNonResident)
    }
}

func (cb *Couchbase) addBucketToCharts(bucket string) {
    cb.addDimToChart(bucketQuotaPercentUsedChart.ID, &module.Dim{
        ID:   indexDimID(bucket, "quota_percent_used"),
        Name: bucket,
        Div:  precision,
    })

    cb.addDimToChart(bucketOpsPerSecChart.ID, &module.Dim{
        ID:   indexDimID(bucket, "ops_per_sec"),
        Name: bucket,
        Div:  precision,
    })

    cb.addDimToChart(bucketDiskFetchesChart.ID, &module.Dim{
        ID:   indexDimID(bucket, "disk_fetches"),
        Name: bucket,
    })

    cb.addDimToChart(bucketItemCountChart.ID, &module.Dim{
        ID:   indexDimID(bucket, "item_count"),
        Name: bucket,
    })

    cb.addDimToChart(bucketDiskUsedChart.ID, &module.Dim{
        ID:   indexDimID(bucket, "disk_used"),
        Name: bucket,
    })

    cb.addDimToChart(bucketDataUsedChart.ID, &module.Dim{
        ID:   indexDimID(bucket, "data_used"),
        Name: bucket,
    })

    cb.addDimToChart(bucketMemUsedChart.ID, &module.Dim{
        ID:   indexDimID(bucket, "mem_used"),
        Name: bucket,
    })

    cb.addDimToChart(bucketVBActiveNumNonResidentChart.ID, &module.Dim{
        ID:   indexDimID(bucket, "vb_active_num_non_resident"),
        Name: bucket,
    })
}

func (cb *Couchbase) addDimToChart(chartID string, dim *module.Dim) {
    chart := cb.Charts().Get(chartID)
    if chart == nil {
        cb.Warningf("error on adding '%s' dimension: can not find '%s' chart", dim.ID, chartID)
        return
    }
    if err := chart.AddDim(dim); err != nil {
        cb.Warning(err)
        return
    }
    chart.MarkNotCreated()
}

func (cb *Couchbase) scrapeCouchbase() (*cbMetrics, error) {
    ms := &cbMetrics{}
    req, _ := web.NewHTTPRequest(cb.Request)
    req.URL.Path = urlPathBucketsStats
    req.URL.RawQuery = url.Values{"skipMap": []string{"true"}}.Encode()

    if err := cb.doOKDecode(req, &ms.BucketsBasicStats); err != nil {
        return nil, err
    }
    return ms, nil
}

func (cb *Couchbase) doOKDecode(req *http.Request, in interface{}) error {
    resp, err := cb.httpClient.Do(req)
    if err != nil {
        return fmt.Errorf("error on HTTP request '%s': %v", req.URL, err)
    }
    defer closeBody(resp)

    if resp.StatusCode != http.StatusOK {
        return fmt.Errorf("'%s' returned HTTP status code: %d", req.URL, resp.StatusCode)
    }

    if err := json.NewDecoder(resp.Body).Decode(in); err != nil {
        return fmt.Errorf("error on decoding response from '%s': %v", req.URL, err)
    }
    return nil
}

func closeBody(resp *http.Response) {
    if resp != nil && resp.Body != nil {
        _, _ = io.Copy(io.Discard, resp.Body)
        _ = resp.Body.Close()
    }
}

func indexDimID(name, metric string) string {
    return fmt.Sprintf("bucket_%s_%s", name, metric)
}