Use only target address for allocation in consistent-hashing strategy (…

…open-telemetry#2290)

Co-authored-by: Jacob Aronoff <[email protected]>

.chloggen/ta_really-consistent-hashing.yaml

@@ -0,0 +1,16 @@
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: enhancement
+
+# The name of the component, or a single word describing the area of concern, (e.g. operator, target allocator, github action)
+component: target allocator
+
+# A brief description of the change. Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Use only target address for allocation in consistent-hashing strategy
+
+# One or more tracking issues related to the change
+issues: [2280]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:

cmd/otel-allocator/allocation/allocatortest.go

@@ -39,7 +39,7 @@ func MakeNNewTargets(n int, numCollectors int, startingIndex int) map[string]*ta
 			"i":         model.LabelValue(strconv.Itoa(i)),
 			"total":     model.LabelValue(strconv.Itoa(n + startingIndex)),
 		}
-		newTarget := target.NewItem(fmt.Sprintf("test-job-%d", i), "test-url", label, collector)
+		newTarget := target.NewItem(fmt.Sprintf("test-job-%d", i), fmt.Sprintf("test-url-%d", i), label, collector)
 		toReturn[newTarget.Hash()] = newTarget
 	}
 	return toReturn
@@ -64,7 +64,7 @@ func MakeNNewTargetsWithEmptyCollectors(n int, startingIndex int) map[string]*ta
 			"i":     model.LabelValue(strconv.Itoa(i)),
 			"total": model.LabelValue(strconv.Itoa(n + startingIndex)),
 		}
-		newTarget := target.NewItem(fmt.Sprintf("test-job-%d", i), "test-url", label, "")
+		newTarget := target.NewItem(fmt.Sprintf("test-job-%d", i), fmt.Sprintf("test-url-%d", i), label, "")
 		toReturn[newTarget.Hash()] = newTarget
 	}
 	return toReturn

cmd/otel-allocator/allocation/consistent_hashing.go

@@ -15,6 +15,7 @@
 package allocation
 
 import (
+	"strings"
 	"sync"
 
 	"github.com/buraksezer/consistent"
@@ -111,7 +112,7 @@ func (c *consistentHashingAllocator) addTargetToTargetItems(tg *target.Item) {
 		delete(c.targetItemsPerJobPerCollector[tg.CollectorName][tg.JobName], tg.Hash())
 		TargetsPerCollector.WithLabelValues(previousColName.String(), consistentHashingStrategyName).Set(float64(c.collectors[previousColName.String()].NumTargets))
 	}
-	colOwner := c.consistentHasher.LocateKey([]byte(tg.Hash()))
+	colOwner := c.consistentHasher.LocateKey([]byte(strings.Join(tg.TargetURL, "")))
 	tg.CollectorName = colOwner.String()
 	c.targetItems[tg.Hash()] = tg
 	c.addCollectorTargetItemMapping(tg)

cmd/otel-allocator/allocation/consistent_hashing_test.go

@@ -28,7 +28,7 @@ func TestCanSetSingleTarget(t *testing.T) {
 	actualTargetItems := c.TargetItems()
 	assert.Len(t, actualTargetItems, 1)
 	for _, item := range actualTargetItems {
-		assert.Equal(t, "collector-2", item.CollectorName)
+		assert.Equal(t, "collector-0", item.CollectorName)
 	}
 }