[pkg/telemetryquerylanguage] Added Int factory function (#11810) (#13441

)

* [pkg/telemetryquerylanguage] Added Int factory function to TQL (#11810)

* [pkg/telemetryquerylanguage] review fixes

* [pkg/telemetryquerylanguage] review fixes

* [pkg/telemetryquerylanguage] changelog

pkg/telemetryquerylanguage/functions/tqlcommon/README.md

@@ -5,6 +5,7 @@ The following functions can be used in any implementation of the Telemetry Query
 Factory Functions
 - [Join](#join)
 - [IsMatch](#ismatch)
+- [Int](#int)
 
 Functions
 - [set](#set)
@@ -46,6 +47,31 @@ Examples:
 
 - `IsMatch("string", ".*ring")`
 
+## Int
+
+`Int(value)`
+
+The `Int` factory function converts the `value` to int type.
+
+The returned type is int64.
+
+The input `value` types:
+* float64. Fraction is discharged (truncation towards zero).
+* string. Trying to parse an integer from string if it fails then nil will be returned.
+* bool. If `value` is true, then the function will return 1 otherwise 0.
+* int64. The function returns the `value` without changes.
+
+If `value` is another type or parsing failed nil is always returned.
+
+The `value` is either a path expression to a telemetry field to retrieve or a literal.
+
+Examples:
+
+- `Int(attributes["http.status_code"])`
+
+
+- `Int("2.0")`
+
 ## set
 
 `set(target, value)`

pkg/telemetryquerylanguage/functions/tqlcommon/func_int.go

@@ -0,0 +1,47 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http:https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package tqlcommon // import "github.com/open-telemetry/opentelemetry-collector-contrib/pkg/telemetryquerylanguage/functions/tqlcommon"
+
+import (
+ "strconv"
+
+ "github.com/open-telemetry/opentelemetry-collector-contrib/pkg/telemetryquerylanguage/tql"
+)
+
+func Int(target tql.Getter) (tql.ExprFunc, error) {
+ return func(ctx tql.TransformContext) interface{} {
+ value := target.Get(ctx)
+ switch value := value.(type) {
+ case int64:
+ return value
+ case string:
+ intValue, err := strconv.ParseInt(value, 10, 64)
+ if err != nil {
+ return nil
+ }
+
+ return intValue
+ case float64:
+ return (int64)(value)
+ case bool:
+ if value {
+ return int64(1)
+ }
+ return int64(0)
+ default:
+ return nil
+ }
+ }, nil
+}

pkg/telemetryquerylanguage/functions/tqlcommon/func_int_test.go

@@ -0,0 +1,97 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http:https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package tqlcommon
+
+import (
+ "testing"
+
+ "github.com/stretchr/testify/assert"
+
+ "github.com/open-telemetry/opentelemetry-collector-contrib/pkg/telemetryquerylanguage/tql"
+ "github.com/open-telemetry/opentelemetry-collector-contrib/pkg/telemetryquerylanguage/tql/tqltest"
+)
+
+func Test_Int(t *testing.T) {
+ tests := []struct {
+ name string
+ value interface{}
+ expected interface{}
+ }{
+ {
+ name: "string",
+ value: "50",
+ expected: int64(50),
+ },
+ {
+ name: "empty string",
+ value: "",
+ expected: nil,
+ },
+ {
+ name: "not a number string",
+ value: "test",
+ expected: nil,
+ },
+ {
+ name: "int64",
+ value: int64(333),
+ expected: int64(333),
+ },
+ {
+ name: "float64",
+ value: float64(2.7),
+ expected: int64(2),
+ },
+ {
+ name: "float64 without decimal",
+ value: float64(55),
+ expected: int64(55),
+ },
+ {
+ name: "true",
+ value: true,
+ expected: int64(1),
+ },
+ {
+ name: "false",
+ value: false,
+ expected: int64(0),
+ },
+ {
+ name: "nil",
+ value: nil,
+ expected: nil,
+ },
+ {
+ name: "some struct",
+ value: struct{}{},
+ expected: nil,
+ },
+ }
+ for _, tt := range tests {
+ t.Run(tt.name, func(t *testing.T) {
+ ctx := tqltest.TestTransformContext{}
+
+ exprFunc, _ := Int(&tql.StandardGetSetter{
+ Getter: func(_ tql.TransformContext) interface{} {
+ return tt.value
+ },
+ })
+ actual := exprFunc(ctx)
+
+ assert.Equal(t, tt.expected, actual)
+ })
+ }
+}

unreleased/tql_int_function.yaml

@@ -0,0 +1,4 @@
+change_type: enhancement
+component: telemetryquerylanguage
+note: Add the Int factory function.
+issues: [11810]