fix: handle concurrent access on tempcache

this happens when a incremental scrape runs along with a full scrape

api/cache.go

@@ -3,6 +3,7 @@ package api
 import (
 	"fmt"
 	"strings"
+	"sync"
 
 	"github.com/flanksource/commons/logger"
 	v1 "github.com/flanksource/config-db/api/v1"
@@ -19,25 +20,22 @@ func init() {
 
 // TempCache is a temporary cache of config items that is used to speed up config item lookups during scrape, when all config items for a scraper are looked up any way
 type TempCache struct {
-	items     map[string]models.ConfigItem
-	aliases   map[string]string
-	notFound  map[string]struct{}
+	// map[string]models.ConfigItem
+	items     sync.Map
+	aliases   sync.Map
+	notFound  sync.Map
 	scraperID string
 }
 
 func NewTempCache() *TempCache {
-	return &TempCache{
-		items:    make(map[string]models.ConfigItem),
-		aliases:  make(map[string]string),
-		notFound: make(map[string]struct{}),
-	}
+	return &TempCache{}
 }
 
 func (t *TempCache) SetScraperID(id string) {
 	t.scraperID = id
 }
 
-func (t TempCache) GetScraperID() string {
+func (t *TempCache) GetScraperID() string {
 	return t.scraperID
 }
 
@@ -55,7 +53,7 @@ func (t *TempCache) Find(ctx ScrapeContext, lookup v1.ExternalID) (*models.Confi
 		lookup.ScraperID = ctx.ScraperID()
 	}
 
-	if _, ok := t.notFound[lookup.Key()]; ok {
+	if _, ok := t.notFound.Load(lookup.Key()); ok {
 		ctx.Counter("temp_cache_missing_hit",
 			"scraper_id", ctx.ScraperID(),
 			"scrape_type", lo.Ternary(ctx.IsIncrementalScrape(), "incremental", "full"),
@@ -69,8 +67,8 @@ func (t *TempCache) Find(ctx ScrapeContext, lookup v1.ExternalID) (*models.Confi
 		return t.Get(ctx, uid)
 	}
 
-	if alias, ok := t.aliases[lookup.Key()]; ok {
-		return t.Get(ctx, alias)
+	if alias, ok := t.aliases.Load(lookup.Key()); ok {
+		return t.Get(ctx, alias.(string))
 	}
 
 	var result models.ConfigItem
@@ -86,7 +84,7 @@ func (t *TempCache) Find(ctx ScrapeContext, lookup v1.ExternalID) (*models.Confi
 	).Add(1)
 
 	if result.ID == "" {
-		t.notFound[lookup.Key()] = struct{}{}
+		t.notFound.Store(lookup.Key(), struct{}{})
 		return nil, nil
 	}
 
@@ -101,21 +99,19 @@ func (t *TempCache) Insert(item models.ConfigItem) {
 	}
 	for _, extID := range item.ExternalID {
 		key := v1.ExternalID{ConfigType: item.Type, ExternalID: extID, ScraperID: scraperID}.Key()
-		t.aliases[key] = item.ID
+		t.aliases.Store(key, item.ID)
 
 		// Remove from nonFound cache
-		delete(t.notFound, key)
+		t.notFound.Delete(key)
 	}
 
-	t.items[strings.ToLower(item.ID)] = item
-	delete(t.notFound, strings.ToLower(item.ID))
+	t.items.Store(strings.ToLower(item.ID), item)
+	t.notFound.Delete(strings.ToLower(item.ID))
 }
 
 type CacheOption string
 
-var (
-	IgnoreNotFound CacheOption = "IgnoreNotFound"
-)
+var IgnoreNotFound CacheOption = "IgnoreNotFound"
 
 func (t *TempCache) Get(ctx ScrapeContext, id string, opts ...CacheOption) (*models.ConfigItem, error) {
 	id = strings.ToLower(id)
@@ -127,7 +123,7 @@ func (t *TempCache) Get(ctx ScrapeContext, id string, opts ...CacheOption) (*mod
 		return opt, true
 	})
 
-	if _, notFound := t.notFound[id]; notFound && !optMap[IgnoreNotFound] {
+	if _, notFound := t.notFound.Load(id); notFound && !optMap[IgnoreNotFound] {
 		ctx.Counter("temp_cache_missing_hit",
 			"scraper_id", ctx.ScraperID(),
 			"scrape_type", lo.Ternary(ctx.IsIncrementalScrape(), "incremental", "full"),
@@ -136,13 +132,15 @@ func (t *TempCache) Get(ctx ScrapeContext, id string, opts ...CacheOption) (*mod
 		return nil, nil
 	}
 
-	if item, ok := t.items[id]; ok {
+	if item, ok := t.items.Load(id); ok {
 		ctx.Counter("temp_cache_hit",
 			"scraper_id", ctx.ScraperID(),
 			"scrape_type", lo.Ternary(ctx.IsIncrementalScrape(), "incremental", "full"),
 			"query_type", "id",
 		).Add(1)
-		return &item, nil
+
+		config := item.(models.ConfigItem)
+		return &config, nil
 	}
 
 	result := models.ConfigItem{}
@@ -172,7 +170,7 @@ func (t *TempCache) Get(ctx ScrapeContext, id string, opts ...CacheOption) (*mod
 		t.Insert(result)
 		return &result, nil
 	} else {
-		t.notFound[id] = struct{}{}
+		t.notFound.Store(id, struct{}{})
 	}
 
 	return nil, nil