[ES][v2] Implement WriteTraces for v2 (jaegertracing#7020)

## Which problem is this PR solving?
-  Fixes a part of: jaegertracing#6458

## Description of the changes
- Implement the `WriteTraces` method for v2

## How was this change tested?
- Unit Tests

## Checklist
- [x] I have read
https://github.com/jaegertracing/jaeger/blob/master/CONTRIBUTING_GUIDELINES.md
- [x] I have signed all commits
- [x] I have added unit tests for the new functionality
- [x] I have run lint and test steps successfully
  - for `jaeger`: `make lint test`
  - for `jaeger-ui`: `npm run lint` and `npm run test`

Signed-off-by: Manik2708 <[email protected]>
Signed-off-by: amol-verma-allen <[email protected]>

Author: Manik2708

internal/storage/v2/elasticsearch/tracestore/writer.go

@@ -0,0 +1,43 @@
+// Copyright (c) 2025 The Jaeger Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+package tracestore
+
+import (
+	"context"
+
+	"go.opentelemetry.io/collector/pdata/ptrace"
+
+	"github.com/jaegertracing/jaeger-idl/model/v1"
+	cfg "github.com/jaegertracing/jaeger/internal/storage/elasticsearch/config"
+	"github.com/jaegertracing/jaeger/internal/storage/v1/elasticsearch/spanstore"
+)
+
+type TraceWriter struct {
+	spanWriter spanstore.CoreSpanWriter
+}
+
+// NewTraceWriter returns the TraceWriter for use
+func NewTraceWriter(p spanstore.SpanWriterParams) *TraceWriter {
+	return &TraceWriter{
+		spanWriter: spanstore.NewSpanWriter(p),
+	}
+}
+
+// WriteTraces convert the traces to ES Span model and write into the database
+func (t *TraceWriter) WriteTraces(_ context.Context, td ptrace.Traces) error {
+	dbSpans := ToDBModel(td)
+	for i := 0; i < len(dbSpans); i++ {
+		span := &dbSpans[i]
+		t.spanWriter.WriteSpan(model.EpochMicrosecondsAsTime(span.StartTime), span)
+	}
+	return nil
+}
+
+func (t *TraceWriter) CreateTemplates(spanTemplate, serviceTemplate string, indexPrefix cfg.IndexPrefix) error {
+	return t.spanWriter.CreateTemplates(spanTemplate, serviceTemplate, indexPrefix)
+}
+
+func (t *TraceWriter) Close() error {
+	return t.spanWriter.Close()
+}

internal/storage/v2/elasticsearch/tracestore/writer_test.go

@@ -0,0 +1,54 @@
+// Copyright (c) 2025 The Jaeger Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+package tracestore
+
+import (
+	"context"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"go.opentelemetry.io/collector/pdata/ptrace"
+
+	"github.com/jaegertracing/jaeger-idl/model/v1"
+	cfg "github.com/jaegertracing/jaeger/internal/storage/elasticsearch/config"
+	"github.com/jaegertracing/jaeger/internal/storage/v1/elasticsearch/spanstore"
+	"github.com/jaegertracing/jaeger/internal/storage/v1/elasticsearch/spanstore/mocks"
+)
+
+func TestTraceWriter_WriteTraces(t *testing.T) {
+	coreWriter := &mocks.CoreSpanWriter{}
+	td := ptrace.NewTraces()
+	resourceSpans := td.ResourceSpans().AppendEmpty()
+	resourceSpans.Resource().Attributes().PutStr("service.name", "testing-service")
+	span := resourceSpans.ScopeSpans().AppendEmpty().Spans().AppendEmpty()
+	span.SetName("op-1")
+	dbSpan := ToDBModel(td)
+	writer := TraceWriter{spanWriter: coreWriter}
+	coreWriter.On("WriteSpan", model.EpochMicrosecondsAsTime(dbSpan[0].StartTime), &dbSpan[0])
+	err := writer.WriteTraces(context.Background(), td)
+	require.NoError(t, err)
+}
+
+func TestTraceWriter_Close(t *testing.T) {
+	coreWriter := &mocks.CoreSpanWriter{}
+	coreWriter.On("Close").Return(nil)
+	writer := TraceWriter{spanWriter: coreWriter}
+	err := writer.Close()
+	require.NoError(t, err)
+}
+
+func TestTraceWriter_CreateTemplates(t *testing.T) {
+	coreWriter := &mocks.CoreSpanWriter{}
+	coreWriter.On("CreateTemplates", "testing-template", "testing-template", cfg.IndexPrefix("testing")).Return(nil)
+	writer := TraceWriter{spanWriter: coreWriter}
+	err := writer.CreateTemplates("testing-template", "testing-template", "testing")
+	require.NoError(t, err)
+}
+
+func Test_NewTraceWriter(t *testing.T) {
+	params := spanstore.SpanWriterParams{}
+	writer := NewTraceWriter(params)
+	assert.NotNil(t, writer)
+}