Fix a bug when parsing a struct in the github.com/nginxinc/telemetry-…

…exporter/pkg/telemetry package

cmd/generator/code.go

@@ -24,7 +24,10 @@ This is a generated file. DO NOT EDIT.
 import (
 	"go.opentelemetry.io/otel/attribute"
 
-	{{ if .TelemetryPackagePath }}"{{ .TelemetryPackagePath }}"{{ end }}
+	{{ if .TelemetryPackagePath }}
+	{{ if .TelemetryPackageAlias }}{{ .TelemetryPackageAlias }} {{ end -}}
+	"{{ .TelemetryPackagePath }}"
+	{{ end }}
 )
 
 func (d *{{ .StructName }}) Attributes() []attribute.KeyValue {
@@ -43,6 +46,7 @@ var _ {{ .ExportablePackagePrefix }}Exportable = (*{{ .StructName }})(nil)
 type codeGen struct {
 	PackageName             string
 	TelemetryPackagePath    string
+	TelemetryPackageAlias   string
 	ExportablePackagePrefix string
 	StructName              string
 	BuildTags               string
@@ -98,18 +102,31 @@ func generateCode(writer io.Writer, cfg codeGenConfig) error {
 		codeFields = append(codeFields, cf)
 	}
 
-	var telemetryPkg string
-	var exportablePkgPrefix string
+	const alias = "ngxTelemetry"
+
+	var (
+		telemetryPkg        string
+		exportablePkgPrefix string
+		telemetryPkgAlias   string
+	)
 
 	// check if we generate code for the type in the telemetry package or any other package
 	if cfg.packagePath != telemetryPackagePath {
 		telemetryPkg = telemetryPackagePath
-		exportablePkgPrefix = getPackageName(telemetryPackagePath) + "."
+
+		// if the name of the package is the same as the telemetry package, we need to use an alias
+		if getPackageName(cfg.packagePath) == getPackageName(telemetryPackagePath) {
+			exportablePkgPrefix = alias + "."
+			telemetryPkgAlias = alias
+		} else {
+			exportablePkgPrefix = getPackageName(telemetryPackagePath) + "."
+		}
 	}
 
 	cg := codeGen{
 		PackageName:             getPackageName(cfg.packagePath),
 		ExportablePackagePrefix: exportablePkgPrefix,
+		TelemetryPackageAlias:   telemetryPkgAlias,
 		TelemetryPackagePath:    telemetryPkg,
 		StructName:              cfg.typeName,
 		Fields:                  codeFields,

cmd/generator/tests/data_attributes_generated.go

@@ -6,7 +6,10 @@ This is a generated file. DO NOT EDIT.
 
 import (
 	"go.opentelemetry.io/otel/attribute"
+
+
 	"github.com/nginxinc/telemetry-exporter/pkg/telemetry"
+
 )
 
 func (d *Data) Attributes() []attribute.KeyValue {

cmd/generator/tests/subtests/anotherdata_attributes_generated.go

@@ -6,7 +6,10 @@ This is a generated file. DO NOT EDIT.
 
 import (
 	"go.opentelemetry.io/otel/attribute"
+
+
 	"github.com/nginxinc/telemetry-exporter/pkg/telemetry"
+
 )
 
 func (d *AnotherData) Attributes() []attribute.KeyValue {

cmd/generator/tests/telemetry/moredata.go

@@ -0,0 +1,13 @@
+//go:build generator
+
+package telemetry
+
+// MoreData is used to ensure that the generator produces the correct code for a struct in a package with the name
+// 'telemetry'.
+// Correctness is confirmed by the fact the generated code compiles.
+//
+//go:generate go run -tags generator github.com/nginxinc/telemetry-exporter/cmd/generator -type=MoreData -build-tags=generator
+type MoreData struct {
+	// StringField is a string field.
+	StringField string
+}

cmd/generator/tests/telemetry/moredata_attributes_generated.go

@@ -0,0 +1,24 @@
+//go:build generator
+package telemetry
+/*
+This is a generated file. DO NOT EDIT.
+*/
+
+import (
+	"go.opentelemetry.io/otel/attribute"
+
+
+	ngxTelemetry "github.com/nginxinc/telemetry-exporter/pkg/telemetry"
+
+)
+
+func (d *MoreData) Attributes() []attribute.KeyValue {
+	var attrs []attribute.KeyValue
+
+	attrs = append(attrs, attribute.String("StringField", d.StringField))
+
+
+	return attrs
+}
+
+var _ ngxTelemetry.Exportable = (*MoreData)(nil)

pkg/telemetry/data_attributes_generated.go

@@ -0,0 +1,22 @@
+
+package telemetry
+/*
+This is a generated file. DO NOT EDIT.
+*/
+
+import (
+	"go.opentelemetry.io/otel/attribute"
+
+
+)
+
+func (d *Data) Attributes() []attribute.KeyValue {
+	var attrs []attribute.KeyValue
+
+	attrs = append(attrs, attribute.Int64("Nodes", d.Nodes))
+
+
+	return attrs
+}
+
+var _ Exportable = (*Data)(nil)

pkg/telemetry/exporter.go

@@ -11,6 +11,18 @@ import (
 	sdktrace "go.opentelemetry.io/otel/sdk/trace"
 )
 
+// Data includes common telemetry data points.
+// FIXME(pleshakov): Define the data points.
+// Currently, only one data point is added, for the only reason that we can make sure the generator
+// generates code for a struct defined in this package.
+// https://github.com/nginxinc/telemetry-exporter/issues/8 will define the actual data points.
+//
+//go:generate go run -tags=generator github.com/nginxinc/telemetry-exporter/cmd/generator -type Data
+type Data struct {
+	// Nodes is a number of nodes.
+	Nodes int64
+}
+
 // Exportable allows exporting telemetry data using the Exporter.
 type Exportable interface {
 	// Attributes returns a list of key-value pairs that represent the telemetry data.