fix: CrateDB replace dots in tag keys with underscores (#9566)

(cherry picked from commit eb41218)

plugins/outputs/cratedb/README.md

@@ -35,4 +35,6 @@ config option, see below.
   table = "metrics"
   # If true, and the metrics table does not exist, create it automatically.
   table_create = true
+  # The character(s) to replace any '.' in an object key with
+  key_separator = "_"
 ```

plugins/outputs/cratedb/cratedb.go

@@ -20,11 +20,12 @@ import (
 const MaxInt64 = int64(^uint64(0) >> 1)
 
 type CrateDB struct {
-	URL         string
-	Timeout     config.Duration
-	Table       string
-	TableCreate bool `toml:"table_create"`
-	DB          *sql.DB
+	URL          string
+	Timeout      config.Duration
+	Table        string
+	TableCreate  bool   `toml:"table_create"`
+	KeySeparator string `toml:"key_separator"`
+	DB           *sql.DB
 }
 
 var sampleConfig = `
@@ -37,6 +38,8 @@ var sampleConfig = `
   table = "metrics"
   # If true, and the metrics table does not exist, create it automatically.
   table_create = true
+  # The character(s) to replace any '.' in an object key with
+  key_separator = "_"
 `
 
 func (c *CrateDB) Connect() error {
@@ -68,15 +71,21 @@ CREATE TABLE IF NOT EXISTS ` + c.Table + ` (
 func (c *CrateDB) Write(metrics []telegraf.Metric) error {
 	ctx, cancel := context.WithTimeout(context.Background(), time.Duration(c.Timeout))
 	defer cancel()
-	if sql, err := insertSQL(c.Table, metrics); err != nil {
+
+	generatedSQL, err := insertSQL(c.Table, c.KeySeparator, metrics)
+	if err != nil {
 		return err
-	} else if _, err := c.DB.ExecContext(ctx, sql); err != nil {
+	}
+
+	_, err = c.DB.ExecContext(ctx, generatedSQL)
+	if err != nil {
 		return err
 	}
+
 	return nil
 }
 
-func insertSQL(table string, metrics []telegraf.Metric) (string, error) {
+func insertSQL(table string, keyReplacement string, metrics []telegraf.Metric) (string, error) {
 	rows := make([]string, len(metrics))
 	for i, m := range metrics {
 		cols := []interface{}{
@@ -89,7 +98,7 @@ func insertSQL(table string, metrics []telegraf.Metric) (string, error) {
 
 		escapedCols := make([]string, len(cols))
 		for i, col := range cols {
-			escaped, err := escapeValue(col)
+			escaped, err := escapeValue(col, keyReplacement)
 			if err != nil {
 				return "", err
 			}
@@ -113,7 +122,7 @@ VALUES
 // inputs.
 //
 // [1] https://github.com/influxdata/telegraf/pull/3210#issuecomment-339273371
-func escapeValue(val interface{}) (string, error) {
+func escapeValue(val interface{}, keyReplacement string) (string, error) {
 	switch t := val.(type) {
 	case string:
 		return escapeString(t, `'`), nil
@@ -131,11 +140,11 @@ func escapeValue(val interface{}) (string, error) {
 		return strconv.FormatBool(t), nil
 	case time.Time:
 		// see https://crate.io/docs/crate/reference/sql/data_types.html#timestamp
-		return escapeValue(t.Format("2006-01-02T15:04:05.999-0700"))
+		return escapeValue(t.Format("2006-01-02T15:04:05.999-0700"), keyReplacement)
 	case map[string]string:
-		return escapeObject(convertMap(t))
+		return escapeObject(convertMap(t), keyReplacement)
 	case map[string]interface{}:
-		return escapeObject(t)
+		return escapeObject(t, keyReplacement)
 	default:
 		// This might be panic worthy under normal circumstances, but it's probably
 		// better to not shut down the entire telegraf process because of one
@@ -154,7 +163,7 @@ func convertMap(m map[string]string) map[string]interface{} {
 	return c
 }
 
-func escapeObject(m map[string]interface{}) (string, error) {
+func escapeObject(m map[string]interface{}, keyReplacement string) (string, error) {
 	// There is a decent chance that the implementation below doesn't catch all
 	// edge cases, but it's hard to tell since the format seems to be a bit
 	// underspecified.
@@ -171,12 +180,15 @@ func escapeObject(m map[string]interface{}) (string, error) {
 	// Now we build our key = val pairs
 	pairs := make([]string, 0, len(m))
 	for _, k := range keys {
-		// escape the value of our key k (potentially recursive)
-		val, err := escapeValue(m[k])
+		key := escapeString(strings.ReplaceAll(k, ".", keyReplacement), `"`)
+
+		// escape the value of the value at k (potentially recursive)
+		val, err := escapeValue(m[k], keyReplacement)
 		if err != nil {
 			return "", err
 		}
-		pairs = append(pairs, escapeString(k, `"`)+" = "+val)
+
+		pairs = append(pairs, key+" = "+val)
 	}
 	return `{` + strings.Join(pairs, ", ") + `}`, nil
 }

plugins/outputs/cratedb/cratedb_test.go

@@ -2,7 +2,6 @@ package cratedb
 
 import (
 	"database/sql"
-	"fmt"
 	"os"
 	"strings"
 	"testing"
@@ -49,9 +48,9 @@ func TestConnectAndWriteIntegration(t *testing.T) {
 	// the rows using their primary keys in order to take advantage of
 	// read-after-write consistency in CrateDB.
 	for _, m := range metrics {
-		hashIDVal, err := escapeValue(hashID(m))
+		hashIDVal, err := escapeValue(hashID(m), "_")
 		require.NoError(t, err)
-		timestamp, err := escapeValue(m.Time())
+		timestamp, err := escapeValue(m.Time(), "_")
 		require.NoError(t, err)
 
 		var id int64
@@ -85,25 +84,21 @@ VALUES
 	}
 
 	for _, test := range tests {
-		if got, err := insertSQL("my_table", test.Metrics); err != nil {
+		if got, err := insertSQL("my_table", "_", test.Metrics); err != nil {
 			t.Error(err)
 		} else if got != test.Want {
 			t.Errorf("got:\n%s\n\nwant:\n%s", got, test.Want)
 		}
 	}
 }
 
-func Test_escapeValueIntegration(t *testing.T) {
-	t.Skip("Skipping due to trust authentication failure")
-
-	if os.Getenv("CIRCLE_PROJECT_REPONAME") != "" {
-		t.Skip("Skipping test on CircleCI due to docker failures")
-	}
+type escapeValueTest struct {
+	Value interface{}
+	Want  string
+}
 
-	tests := []struct {
-		Val  interface{}
-		Want string
-	}{
+func escapeValueTests() []escapeValueTest {
+	return []escapeValueTest{
 		// string
 		{`foo`, `'foo'`},
 		{`foo'bar 'yeah`, `'foo''bar ''yeah'`},
@@ -122,6 +117,7 @@ func Test_escapeValueIntegration(t *testing.T) {
 		{map[string]string(nil), `{}`},
 		{map[string]string{"foo": "bar"}, `{"foo" = 'bar'}`},
 		{map[string]string{"foo": "bar", "one": "more"}, `{"foo" = 'bar', "one" = 'more'}`},
+		{map[string]string{"f.oo": "bar", "o.n.e": "more"}, `{"f_oo" = 'bar', "o_n_e" = 'more'}`},
 		// map[string]interface{}
 		{map[string]interface{}{}, `{}`},
 		{map[string]interface{}(nil), `{}`},
@@ -130,29 +126,47 @@ func Test_escapeValueIntegration(t *testing.T) {
 		{map[string]interface{}{"foo": map[string]interface{}{"one": "more"}}, `{"foo" = {"one" = 'more'}}`},
 		{map[string]interface{}{`fo"o`: `b'ar`, `ab'c`: `xy"z`, `on"""e`: `mo'''re`}, `{"ab'c" = 'xy"z', "fo""o" = 'b''ar', "on""""""e" = 'mo''''''re'}`},
 	}
+}
 
-	url := testURL()
-	fmt.Println("url", url)
-	db, err := sql.Open("pgx", url)
+func Test_escapeValueIntegration(t *testing.T) {
+	t.Skip("Skipping due to trust authentication failure")
+
+	if os.Getenv("CIRCLE_PROJECT_REPONAME") != "" {
+		t.Skip("Skipping test on CircleCI due to docker failures")
+	}
+
+	db, err := sql.Open("pgx", testURL())
 	require.NoError(t, err)
 	defer db.Close()
 
+	tests := escapeValueTests()
 	for _, test := range tests {
-		got, err := escapeValue(test.Val)
-		if err != nil {
-			t.Errorf("val: %#v: %s", test.Val, err)
-		} else if got != test.Want {
-			t.Errorf("got:\n%s\n\nwant:\n%s", got, test.Want)
-		}
+		got, err := escapeValue(test.Value, "_")
+		require.NoError(t, err, "value: %#v", test.Value)
 
 		// This is a smoke test that will blow up if our escaping causing a SQL
-		// syntax error, which may allow for an attack.
+		// syntax error, which may allow for an attack.=
 		var reply interface{}
 		row := db.QueryRow("SELECT " + got)
 		require.NoError(t, row.Scan(&reply))
 	}
 }
 
+func Test_escapeValue(t *testing.T) {
+	tests := escapeValueTests()
+	for _, test := range tests {
+		got, err := escapeValue(test.Value, "_")
+		require.NoError(t, err, "value: %#v", test.Value)
+		require.Equal(t, got, test.Want)
+	}
+}
+
+func Test_circumeventingStringEscape(t *testing.T) {
+	value, err := escapeObject(map[string]interface{}{"a.b": "c"}, `_"`)
+	require.NoError(t, err)
+	require.Equal(t, value, `{"a_""b" = 'c'}`)
+}
+
 func Test_hashID(t *testing.T) {
 	tests := []struct {
 		Name   string