Merge pull request #3630 from influxdata/bugfix/regex-template-vars

Fix rendering of template variables within regexes

influx/templates.go

@@ -1,6 +1,7 @@
 package influx
 
 import (
+	"regexp"
 	"sort"
 	"strconv"
 	"strings"
@@ -49,13 +50,30 @@ func RenderTemplate(query string, t chronograf.TemplateVar, now time.Time) (stri
 		return query, nil
 	}
 
+	var q string
+
+	// First render template variable usages appearing within an InfluxQL regular expression (value should appear unquoted)
+	switch t.Values[0].Type {
+	case "tagKey", "fieldKey", "measurement", "tagValue":
+		r, err := regexp.Compile(`(/[.^/]*)(` + regexp.QuoteMeta(t.Var) + `)([.^/]*/)`)
+
+		if err != nil {
+			return "", err
+		}
+
+		q = r.ReplaceAllString(query, `${1}`+t.Values[0].Value+`${3}`)
+	default:
+		q = query
+	}
+
+	// Then render template variable usages not appearing in an InfluxQL regular expression (values may be quoted)
 	switch t.Values[0].Type {
 	case "tagKey", "fieldKey", "measurement", "database":
-		return strings.Replace(query, t.Var, `"`+t.Values[0].Value+`"`, -1), nil
+		return strings.Replace(q, t.Var, `"`+t.Values[0].Value+`"`, -1), nil
 	case "tagValue", "timeStamp":
-		return strings.Replace(query, t.Var, `'`+t.Values[0].Value+`'`, -1), nil
+		return strings.Replace(q, t.Var, `'`+t.Values[0].Value+`'`, -1), nil
 	case "csv", "constant":
-		return strings.Replace(query, t.Var, t.Values[0].Value, -1), nil
+		return strings.Replace(q, t.Var, t.Values[0].Value, -1), nil
 	}
 
 	tv := map[string]string{}

influx/templates_test.go

@@ -297,6 +297,32 @@ func TestTemplateReplace(t *testing.T) {
 			},
 			want: `SHOW DATABASES`,
 		},
+		{
+			name:  "query with some tagValue template variables inside a regex",
+			query: `SELECT "usage_active" FROM "cpu" WHERE host =~ /:host:/ AND time > :dashboardTime: FILL(null)`,
+			vars: []chronograf.TemplateVar{
+				{
+					Var: ":host:",
+					Values: []chronograf.TemplateValue{
+						{
+							Value: "my-host.local",
+							Type:  "tagValue",
+						},
+					},
+				},
+				{
+					Var: ":dashboardTime:",
+					Values: []chronograf.TemplateValue{
+						{
+							Value:    "now() - 1h",
+							Type:     "constant",
+							Selected: true,
+						},
+					},
+				},
+			},
+			want: `SELECT "usage_active" FROM "cpu" WHERE host =~ /my-host.local/ AND time > now() - 1h FILL(null)`,
+		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {