added test folder for testing interface

pkg/query-service/app/clickhouseReader/reader.go

@@ -0,0 +1,76 @@
+package clickhouseReader
+
+import (
+	"context"
+	"database/sql"
+	"errors"
+	"fmt"
+	"time"
+)
+
+const (
+	minTimespanForProgressiveSearch       = time.Hour
+	minTimespanForProgressiveSearchMargin = time.Minute
+	maxProgressiveSteps                   = 4
+)
+
+var (
+	ErrNoOperationsTable = errors.New("no operations table supplied")
+	ErrNoIndexTable      = errors.New("no index table supplied")
+	ErrStartTimeRequired = errors.New("start time is required for search queries")
+)
+
+// SpanWriter for reading spans from ClickHouse
+type TraceReader struct {
+	db              *sql.DB
+	operationsTable string
+	indexTable      string
+	spansTable      string
+}
+
+// NewTraceReader returns a TraceReader for the database
+func NewTraceReader(db *sql.DB, operationsTable, indexTable, spansTable string) *TraceReader {
+	return &TraceReader{
+		db:              db,
+		operationsTable: operationsTable,
+		indexTable:      indexTable,
+		spansTable:      spansTable,
+	}
+}
+
+func (r *TraceReader) getStrings(ctx context.Context, sql string, args ...interface{}) ([]string, error) {
+	rows, err := r.db.QueryContext(ctx, sql, args...)
+	if err != nil {
+		return nil, err
+	}
+
+	defer rows.Close()
+
+	values := []string{}
+
+	for rows.Next() {
+		var value string
+		if err := rows.Scan(&value); err != nil {
+			return nil, err
+		}
+		values = append(values, value)
+	}
+
+	if err := rows.Err(); err != nil {
+		return nil, err
+	}
+
+	return values, nil
+}
+
+// GetServices fetches the sorted service list that have not expired
+func (r *TraceReader) GetServices(ctx context.Context) ([]string, error) {
+
+	if r.operationsTable == "" {
+		return nil, ErrNoOperationsTable
+	}
+
+	query := fmt.Sprintf("SELECT service FROM %s GROUP BY service", r.operationsTable)
+
+	return r.getStrings(ctx, query)
+}

pkg/query-service/app/druidReader/reader.go

@@ -0,0 +1,22 @@
+package druidReader
+
+import (
+	"go.signoz.io/query-service/druidQuery"
+	"go.signoz.io/query-service/model"
+)
+
+type DruidReader struct {
+	Client
+	SqlClient
+}
+
+func NewSpanReader() {
+	initialize()
+}
+func initialize() {
+
+}
+
+func (druid *Druid) GetServices(client, query *model.GetServicesParams) {
+	return druidQuery.GetServices(druid.sqlClient, query)
+}

pkg/query-service/app/fatory.go

@@ -0,0 +1,12 @@
+// Reader finds and loads traces and other data from storage.
+type QueryReader interface {
+	// GetTrace(ctx context.Context, traceID model.TraceID) (*model.Trace, error)
+	GetServices(ctx context.Context)
+	// GetOperations(ctx context.Context, query OperationQueryParameters) ([]Operation, error)
+	// FindTraces(ctx context.Context, query *TraceQueryParameters) ([]*model.Trace, error)
+	// FindTraceIDs(ctx context.Context, query *TraceQueryParameters) ([]model.TraceID, error)
+}
+
+func NewQueryReader() {
+
+}

pkg/query-service/test/clickhouse/clickhouse.go

@@ -0,0 +1,20 @@
+package clickhouse
+
+type ClickHouseReader struct {
+	ClickHouseClientUrl string
+}
+
+func connect() string {
+	return "Connected to ClickHouse"
+}
+
+func NewSpanReader() *ClickHouseReader {
+	connect()
+	return &ClickHouseReader{
+		ClickHouseClientUrl: "http://localhost:9000",
+	}
+}
+
+func (chReader *ClickHouseReader) GetServices() string {
+	return "Hello from ClickHouse"
+}

pkg/query-service/test/druid/druid.go

@@ -0,0 +1,20 @@
+package druid
+
+type DruidReader struct {
+	DruidClientUrl string
+}
+
+func connect() string {
+	return "Connected to Druid"
+}
+
+func NewSpanReader() *DruidReader {
+	connect()
+	return &DruidReader{
+		DruidClientUrl: "http://localhost:8888",
+	}
+}
+
+func (druidReader *DruidReader) GetServices() string {
+	return "Hello from Druid"
+}

pkg/query-service/test/test.go

@@ -0,0 +1,27 @@
+package main
+
+import (
+	"fmt"
+	"os"
+
+	"go.signoz.io/query-service/test/clickhouse"
+	"go.signoz.io/query-service/test/druid"
+)
+
+type StorageReader interface {
+	GetServices() string
+}
+
+func main() {
+	storage := os.Getenv("STORAGE")
+	var client StorageReader
+
+	if storage == "druid" {
+		client = druid.NewSpanReader()
+	} else if storage == "clickhouse" {
+		client = clickhouse.NewSpanReader()
+	}
+
+	services := client.GetServices()
+	fmt.Println(services)
+}