grafana/pkg/tsdb/azuremonitor/macros.go
Chad Nedzlek 20faef8de5 AzureMonitor: Alerting for Azure Application Insights (#19381)
* Convert Azure Application Insights datasource to Go

Allows for alerting of Application Insights data source

Closes: #15153

* Fix timeGrainReset

* Default time interval for querys for alerts

* Fix a few rename related bugs

* Update readme to indicate App Insights alerting

* Fix typo and add tests to ensure migration is happening

* Address code review feedback (mostly typos and unintended changes)
2019-10-07 14:18:14 +02:00

119 lines
3.3 KiB
Go

package azuremonitor
import (
"fmt"
"regexp"
"strings"
"time"
"github.com/grafana/grafana/pkg/tsdb"
)
const rsIdentifier = `([_a-zA-Z0-9]+)`
const sExpr = `\$` + rsIdentifier + `(?:\(([^\)]*)\))?`
type kqlMacroEngine struct {
timeRange *tsdb.TimeRange
query *tsdb.Query
}
func KqlInterpolate(query *tsdb.Query, timeRange *tsdb.TimeRange, kql string) (string, error) {
engine := kqlMacroEngine{}
return engine.Interpolate(query, timeRange, kql)
}
func (m *kqlMacroEngine) Interpolate(query *tsdb.Query, timeRange *tsdb.TimeRange, kql string) (string, error) {
m.timeRange = timeRange
m.query = query
rExp, _ := regexp.Compile(sExpr)
var macroError error
kql = m.ReplaceAllStringSubmatchFunc(rExp, kql, func(groups []string) string {
args := []string{}
if len(groups) > 2 {
args = strings.Split(groups[2], ",")
}
for i, arg := range args {
args[i] = strings.Trim(arg, " ")
}
res, err := m.evaluateMacro(groups[1], args)
if err != nil && macroError == nil {
macroError = err
return "macro_error()"
}
return res
})
if macroError != nil {
return "", macroError
}
return kql, nil
}
func (m *kqlMacroEngine) evaluateMacro(name string, args []string) (string, error) {
switch name {
case "__timeFilter":
timeColumn := "timestamp"
if len(args) > 0 && args[0] != "" {
timeColumn = args[0]
}
return fmt.Sprintf("['%s'] >= datetime('%s') and ['%s'] <= datetime('%s')", timeColumn, m.timeRange.GetFromAsTimeUTC().Format(time.RFC3339), timeColumn, m.timeRange.GetToAsTimeUTC().Format(time.RFC3339)), nil
case "__from":
return fmt.Sprintf("datetime('%s')", m.timeRange.GetFromAsTimeUTC().Format(time.RFC3339)), nil
case "__to":
return fmt.Sprintf("datetime('%s')", m.timeRange.GetToAsTimeUTC().Format(time.RFC3339)), nil
case "__interval":
var interval time.Duration
if m.query.IntervalMs == 0 {
to := m.timeRange.MustGetTo().UnixNano()
from := m.timeRange.MustGetFrom().UnixNano()
// default to "100 datapoints" if nothing in the query is more specific
defaultInterval := time.Duration((to - from) / 60)
var err error
interval, err = tsdb.GetIntervalFrom(m.query.DataSource, m.query.Model, defaultInterval)
if err != nil {
azlog.Warn("Unable to get interval from query", "datasource", m.query.DataSource, "model", m.query.Model)
interval = defaultInterval
}
} else {
interval = time.Millisecond * time.Duration(m.query.IntervalMs)
}
return fmt.Sprintf("%dms", int(interval/time.Millisecond)), nil
case "__contains":
if len(args) < 2 || args[0] == "" || args[1] == "" {
return "", fmt.Errorf("macro %v needs colName and variableSet", name)
}
if args[1] == "all" {
return "1 == 1", nil
}
return fmt.Sprintf("['%s'] in ('%s')", args[0], args[1]), nil
default:
return "", fmt.Errorf("Unknown macro %v", name)
}
}
func (m *kqlMacroEngine) ReplaceAllStringSubmatchFunc(re *regexp.Regexp, str string, repl func([]string) string) string {
result := ""
lastIndex := 0
for _, v := range re.FindAllSubmatchIndex([]byte(str), -1) {
groups := []string{}
for i := 0; i < len(v); i += 2 {
if v[i] < 0 {
groups = append(groups, "")
} else {
groups = append(groups, str[v[i]:v[i+1]])
}
}
result += str[lastIndex:v[0]] + repl(groups)
lastIndex = v[1]
}
return result + str[lastIndex:]
}