file.go

Documentation: github.com/cybertec-postgresql/pgwatch/v3/internal/reaper

     1  package reaper
     2  
     3  import (
     4  	"context"
     5  	"os"
     6  
     7  	"github.com/cybertec-postgresql/pgwatch/v3/internal/metrics"
     8  )
     9  
    10  func DoesEmergencyTriggerfileExist(fname string) bool {
    11  	// Main idea of the feature is to be able to quickly free monitored DBs / network of any extra "monitoring effect" load.
    12  	// In highly automated K8s / IaC environments such a temporary change might involve pull requests, peer reviews, CI/CD etc
    13  	// which can all take too long vs "exec -it pgwatch-pod -- touch /tmp/pgwatch-emergency-pause".
    14  	// After creating the file it can still take up to --servers-refresh-loop-seconds (2min def.) for change to take effect!
    15  	if fname == "" {
    16  		return false
    17  	}
    18  	_, err := os.Stat(fname)
    19  	return err == nil
    20  }
    21  
    22  const (
    23  	metricCPULoad           = "cpu_load"
    24  	metricPsutilCPU         = "psutil_cpu"
    25  	metricPsutilDisk        = "psutil_disk"
    26  	metricPsutilDiskIoTotal = "psutil_disk_io_total"
    27  	metricPsutilMem         = "psutil_mem"
    28  )
    29  
    30  const (
    31  	sqlPgDirs = `select 
    32  current_setting('data_directory') as dd, 
    33  current_setting('log_directory') as ld, 
    34  current_setting('server_version_num')::int as pgver`
    35  	sqlTsDirs = `select 
    36  spcname::text as name, 
    37  pg_catalog.pg_tablespace_location(oid) as location 
    38  from pg_catalog.pg_tablespace 
    39  where not spcname like any(array[E'pg\\_%'])`
    40  )
    41  
    42  var directlyFetchableOSMetrics = map[string]bool{metricPsutilCPU: true, metricPsutilDisk: true, metricPsutilDiskIoTotal: true, metricPsutilMem: true, metricCPULoad: true}
    43  
    44  func IsDirectlyFetchableMetric(metric string) bool {
    45  	_, ok := directlyFetchableOSMetrics[metric]
    46  	return ok
    47  }
    48  
    49  func FetchStatsDirectlyFromOS(ctx context.Context, msg MetricFetchConfig, vme MonitoredDatabaseSettings, mvp metrics.Metric) (*metrics.MeasurementEnvelope, error) {
    50  	var data, dataDirs, dataTblspDirs metrics.Measurements
    51  	var err error
    52  
    53  	switch msg.MetricName {
    54  	case metricCPULoad:
    55  		data, err = GetLoadAvgLocal()
    56  	case metricPsutilCPU:
    57  		data, err = GetGoPsutilCPU(msg.Interval)
    58  	case metricPsutilDisk:
    59  		if dataDirs, err = QueryMeasurements(ctx, msg.DBUniqueName, sqlPgDirs); err != nil {
    60  			return nil, err
    61  		}
    62  		if dataTblspDirs, err = QueryMeasurements(ctx, msg.DBUniqueName, sqlTsDirs); err != nil {
    63  			return nil, err
    64  		}
    65  		data, err = GetGoPsutilDiskPG(dataDirs, dataTblspDirs)
    66  	case metricPsutilDiskIoTotal:
    67  		data, err = GetGoPsutilDiskTotals()
    68  	case metricPsutilMem:
    69  		data, err = GetGoPsutilMem()
    70  	}
    71  	if err != nil {
    72  		return nil, err
    73  	}
    74  
    75  	msm, err := DataRowsToMeasurementEnvelope(data, msg, vme, mvp)
    76  	if err != nil {
    77  		return nil, err
    78  	}
    79  	return &msm, nil
    80  }
    81  
    82  // data + custom tags + counters
    83  func DataRowsToMeasurementEnvelope(data metrics.Measurements, msg MetricFetchConfig, vme MonitoredDatabaseSettings, mvp metrics.Metric) (metrics.MeasurementEnvelope, error) {
    84  	md, err := GetMonitoredDatabaseByUniqueName(msg.DBUniqueName)
    85  	if err != nil {
    86  		return metrics.MeasurementEnvelope{}, err
    87  	}
    88  	return metrics.MeasurementEnvelope{
    89  		DBName:           msg.DBUniqueName,
    90  		SourceType:       string(msg.Source),
    91  		MetricName:       msg.MetricName,
    92  		CustomTags:       md.CustomTags,
    93  		Data:             data,
    94  		MetricDef:        mvp,
    95  		RealDbname:       vme.RealDbname,
    96  		SystemIdentifier: vme.SystemIdentifier,
    97  	}, nil
    98  }
    99