Fix null value crash in postgresql_extensible input (#4689)

This commit is contained in:
Greg 2018-09-18 10:08:13 -06:00 committed by Daniel Nelson
parent f05fdde48b
commit d3ad591481
2 changed files with 48 additions and 12 deletions

View File

@ -19,13 +19,7 @@ type Postgresql struct {
postgresql.Service postgresql.Service
Databases []string Databases []string
AdditionalTags []string AdditionalTags []string
Query []struct { Query query
Sqlquery string
Version int
Withdbname bool
Tagvalue string
Measurement string
}
Debug bool Debug bool
} }
@ -127,7 +121,6 @@ func (p *Postgresql) Gather(acc telegraf.Accumulator) error {
) )
// Retreiving the database version // Retreiving the database version
query = `select substring(setting from 1 for 3) as version from pg_settings where name='server_version_num'` query = `select substring(setting from 1 for 3) as version from pg_settings where name='server_version_num'`
if err = p.DB.QueryRow(query).Scan(&db_version); err != nil { if err = p.DB.QueryRow(query).Scan(&db_version); err != nil {
db_version = 0 db_version = 0
@ -135,7 +128,6 @@ func (p *Postgresql) Gather(acc telegraf.Accumulator) error {
// We loop in order to process each query // We loop in order to process each query
// Query is not run if Database version does not match the query version. // Query is not run if Database version does not match the query version.
for i := range p.Query { for i := range p.Query {
sql_query = p.Query[i].Sqlquery sql_query = p.Query[i].Sqlquery
tag_value = p.Query[i].Tagvalue tag_value = p.Query[i].Tagvalue
@ -221,9 +213,14 @@ func (p *Postgresql) accRow(meas_name string, row scanner, acc telegraf.Accumula
return err return err
} }
if columnMap["datname"] != nil { if c, ok := columnMap["datname"]; ok && *c != nil {
// extract the database name from the column map // extract the database name from the column map
dbname.WriteString((*columnMap["datname"]).(string)) switch datname := (*c).(type) {
case string:
dbname.WriteString(datname)
default:
dbname.WriteString("postgres")
}
} else { } else {
dbname.WriteString("postgres") dbname.WriteString("postgres")
} }

View File

@ -1,6 +1,7 @@
package postgresql_extensible package postgresql_extensible
import ( import (
"errors"
"fmt" "fmt"
"testing" "testing"
@ -223,3 +224,41 @@ func TestPostgresqlIgnoresUnwantedColumns(t *testing.T) {
assert.False(t, acc.HasMeasurement(col)) assert.False(t, acc.HasMeasurement(col))
} }
} }
func TestAccRow(t *testing.T) {
p := Postgresql{}
var acc testutil.Accumulator
columns := []string{"datname", "cat"}
testRows := []fakeRow{
{fields: []interface{}{1, "gato"}},
{fields: []interface{}{nil, "gato"}},
{fields: []interface{}{"name", "gato"}},
}
for i := range testRows {
err := p.accRow("pgTEST", testRows[i], &acc, columns)
if err != nil {
t.Fatalf("Scan failed: %s", err)
}
}
}
type fakeRow struct {
fields []interface{}
}
func (f fakeRow) Scan(dest ...interface{}) error {
if len(f.fields) != len(dest) {
return errors.New("Nada matchy buddy")
}
for i, d := range dest {
switch d.(type) {
case (*interface{}):
*d.(*interface{}) = f.fields[i]
default:
return fmt.Errorf("Bad type %T", d)
}
}
return nil
}