[chore] use mdatagen to generate service metrics

This PR follows open-telemetry#10159 and uses the new mdatagen functionality to generate
async metrics in the service.

Signed-off-by: Alex Boten <223565+codeboten@users.noreply.github.com>

service/internal/proctelemetry/process_telemetry.go

@@ -12,13 +12,9 @@ import (
 
 	"github.com/shirou/gopsutil/v3/common"
 	"github.com/shirou/gopsutil/v3/process"
-	otelmetric "go.opentelemetry.io/otel/metric"
-	"go.uber.org/multierr"
-)
 
-const (
-	scopeName      = "go.opentelemetry.io/collector/service/process_telemetry"
-	processNameKey = "process_name"
+	"go.opentelemetry.io/collector/component"
+	"go.opentelemetry.io/collector/service/internal/metadata"
 )
 
 // processMetrics is a struct that contains views related to process metrics (cpu, mem, etc)
@@ -28,13 +24,6 @@ type processMetrics struct {
 	proc              *process.Process
 	context           context.Context
 
-	otelProcessUptime otelmetric.Float64ObservableCounter
-	otelAllocMem      otelmetric.Int64ObservableGauge
-	otelTotalAllocMem otelmetric.Int64ObservableCounter
-	otelSysMem        otelmetric.Int64ObservableGauge
-	otelCPUSeconds    otelmetric.Float64ObservableCounter
-	otelRSSMemory     otelmetric.Int64ObservableGauge
-
 	// mu protects everything bellow.
 	mu         sync.Mutex
 	lastMsRead time.Time
@@ -64,7 +53,7 @@ func WithHostProc(hostProc string) RegisterOption {
 
 // RegisterProcessMetrics creates a new set of processMetrics (mem, cpu) that can be used to measure
 // basic information about this process.
-func RegisterProcessMetrics(mp otelmetric.MeterProvider, ballastSizeBytes uint64, opts ...RegisterOption) error {
+func RegisterProcessMetrics(cfg component.TelemetrySettings, ballastSizeBytes uint64, opts ...RegisterOption) error {
 	set := registerOption{}
 	for _, opt := range opts {
 		opt.apply(&set)
@@ -86,73 +75,15 @@ func RegisterProcessMetrics(mp otelmetric.MeterProvider, ballastSizeBytes uint64
 		return err
 	}
 
-	return pm.record(mp.Meter(scopeName))
-}
-
-func (pm *processMetrics) record(meter otelmetric.Meter) error {
-	var errs, err error
-
-	pm.otelProcessUptime, err = meter.Float64ObservableCounter(
-		"process_uptime",
-		otelmetric.WithDescription("Uptime of the process"),
-		otelmetric.WithUnit("s"),
-		otelmetric.WithFloat64Callback(func(_ context.Context, o otelmetric.Float64Observer) error {
-			o.Observe(pm.updateProcessUptime())
-			return nil
-		}))
-	errs = multierr.Append(errs, err)
-
-	pm.otelAllocMem, err = meter.Int64ObservableGauge(
-		"process_runtime_heap_alloc_bytes",
-		otelmetric.WithDescription("Bytes of allocated heap objects (see 'go doc runtime.MemStats.HeapAlloc')"),
-		otelmetric.WithUnit("By"),
-		otelmetric.WithInt64Callback(func(_ context.Context, o otelmetric.Int64Observer) error {
-			o.Observe(pm.updateAllocMem())
-			return nil
-		}))
-	errs = multierr.Append(errs, err)
-
-	pm.otelTotalAllocMem, err = meter.Int64ObservableCounter(
-		"process_runtime_total_alloc_bytes",
-		otelmetric.WithDescription("Cumulative bytes allocated for heap objects (see 'go doc runtime.MemStats.TotalAlloc')"),
-		otelmetric.WithUnit("By"),
-		otelmetric.WithInt64Callback(func(_ context.Context, o otelmetric.Int64Observer) error {
-			o.Observe(pm.updateTotalAllocMem())
-			return nil
-		}))
-	errs = multierr.Append(errs, err)
-
-	pm.otelSysMem, err = meter.Int64ObservableGauge(
-		"process_runtime_total_sys_memory_bytes",
-		otelmetric.WithDescription("Total bytes of memory obtained from the OS (see 'go doc runtime.MemStats.Sys')"),
-		otelmetric.WithUnit("By"),
-		otelmetric.WithInt64Callback(func(_ context.Context, o otelmetric.Int64Observer) error {
-			o.Observe(pm.updateSysMem())
-			return nil
-		}))
-	errs = multierr.Append(errs, err)
-
-	pm.otelCPUSeconds, err = meter.Float64ObservableCounter(
-		"process_cpu_seconds",
-		otelmetric.WithDescription("Total CPU user and system time in seconds"),
-		otelmetric.WithUnit("s"),
-		otelmetric.WithFloat64Callback(func(_ context.Context, o otelmetric.Float64Observer) error {
-			o.Observe(pm.updateCPUSeconds())
-			return nil
-		}))
-	errs = multierr.Append(errs, err)
-
-	pm.otelRSSMemory, err = meter.Int64ObservableGauge(
-		"process_memory_rss",
-		otelmetric.WithDescription("Total physical memory (resident set size)"),
-		otelmetric.WithUnit("By"),
-		otelmetric.WithInt64Callback(func(_ context.Context, o otelmetric.Int64Observer) error {
-			o.Observe(pm.updateRSSMemory())
-			return nil
-		}))
-	errs = multierr.Append(errs, err)
-
-	return errs
+	_, err = metadata.NewTelemetryBuilder(cfg,
+		metadata.WithProcessUptimeCallback(pm.updateProcessUptime),
+		metadata.WithProcessRuntimeHeapAllocBytesCallback(pm.updateAllocMem),
+		metadata.WithProcessRuntimeTotalAllocBytesCallback(pm.updateTotalAllocMem),
+		metadata.WithProcessRuntimeTotalSysMemoryBytesCallback(pm.updateSysMem),
+		metadata.WithProcessCPUSecondsCallback(pm.updateCPUSeconds),
+		metadata.WithProcessMemoryRssCallback(pm.updateRSSMemory),
+	)
+	return err
 }
 
 func (pm *processMetrics) updateProcessUptime() float64 {