fix issue with old test, add extra test for local eval

.github/workflows/unit-tests.yml

@@ -20,4 +20,4 @@ jobs:
         run: go build .
 
       - name: Test
-        run: go test -v .
+        run: go test -timeout 30s -v .

feature_flags_test.go

@@ -1,12 +1,15 @@
 package posthog
 
 import (
+	"bytes"
 	"encoding/json"
 	"fmt"
+	"log"
 	"net/http"
 	"net/http/httptest"
 	"reflect"
 	"strings"
+	"time"
 
 	"testing"
 )
@@ -613,9 +616,13 @@ func TestFeatureFlagNullComeIntoPlayOnlyWhenDecideErrorsOut(t *testing.T) {
 
 	defer server.Close()
 
+	// TODO: Make this nicer, right now if all local evaluation requests fail, we block
+	// on waiting for atleast one request to happen before returning flags,
+	//  which can be suboptimal
 	client, _ := NewWithConfig("Csyjlnlun3OzyNJAafdlv", Config{
-		PersonalApiKey: "some very secret key",
-		Endpoint:       server.URL,
+		PersonalApiKey:                     "some very secret key",
+		Endpoint:                           server.URL,
+		DefaultFeatureFlagsPollingInterval: 5 * time.Second,
 	})
 	defer client.Close()
 
@@ -3232,3 +3239,148 @@ func TestComplexCohortsWithNegationLocally(t *testing.T) {
 		t.Error("Should match")
 	}
 }
+
+func TestFlagWithTimeoutExceeded(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if strings.HasPrefix(r.URL.Path, "/decide") {
+			time.Sleep(1 * time.Second)
+			w.Write([]byte(fixture("test-decide-v2.json")))
+		} else if strings.HasPrefix(r.URL.Path, "/api/feature_flag/local_evaluation") {
+			w.Write([]byte(fixture("feature_flag/test-flag-group-properties.json")))
+		} else if strings.HasPrefix(r.URL.Path, "/batch/") {
+			// Ignore batch requests
+		} else {
+			t.Error("Unknown request made by library")
+		}
+	}))
+	defer server.Close()
+
+	client, _ := NewWithConfig("Csyjlnlun3OzyNJAafdlv", Config{
+		PersonalApiKey:            "some very secret key",
+		Endpoint:                  server.URL,
+		FeatureFlagRequestTimeout: 10 * time.Millisecond,
+	})
+	defer client.Close()
+
+	isMatch, err := client.IsFeatureEnabled(
+		FeatureFlagPayload{
+			Key:        "enabled-flag",
+			DistinctId: "-",
+		},
+	)
+
+	if err == nil {
+		t.Error("Expected error")
+	}
+	if !strings.Contains(err.Error(), "context deadline exceeded") {
+		t.Error("Expected context deadline exceeded error")
+	}
+	if isMatch != nil {
+		t.Error("Flag shouldn't match")
+	}
+
+	// get all flags with no local evaluation possible
+	variants, err := client.GetAllFlags(
+		FeatureFlagPayloadNoKey{
+			DistinctId: "-",
+			Groups:     Groups{"company": "posthog"},
+		},
+	)
+
+	if err == nil {
+		t.Error("Expected error")
+	}
+	if !strings.Contains(err.Error(), "context deadline exceeded") {
+		t.Error("Expected context deadline exceeded error")
+	}
+
+	if variants == nil || len(variants) != 0 {
+		t.Error("Flag shouldn't match")
+	}
+
+	// get all flags with partial local evaluation possible
+	variants, err = client.GetAllFlags(
+		FeatureFlagPayloadNoKey{
+			DistinctId:       "-",
+			Groups:           Groups{"company": "posthog"},
+			PersonProperties: NewProperties().Set("region", "USA"),
+		},
+	)
+
+	if err == nil {
+		t.Error("Expected error")
+	}
+	if !strings.Contains(err.Error(), "context deadline exceeded") {
+		t.Error("Expected context deadline exceeded error")
+	}
+
+	if variants == nil || len(variants) != 1 || variants["simple-flag"] != true {
+		t.Error("should return locally evaluated flag")
+	}
+
+	// get all flags with full local evaluation possible
+	variants, err = client.GetAllFlags(
+		FeatureFlagPayloadNoKey{
+			DistinctId:       "-",
+			Groups:           Groups{"company": "posthog"},
+			PersonProperties: NewProperties().Set("region", "USA"),
+			GroupProperties:  map[string]Properties{"company": NewProperties().Set("name", "Project Name 1")},
+		},
+	)
+
+	if err != nil {
+		t.Error("Unexpected error")
+	}
+	fmt.Println(variants)
+
+	if variants == nil || len(variants) != 2 || variants["simple-flag"] != true || variants["group-flag"] != true {
+		t.Error("should return locally evaluated flag")
+	}
+}
+
+func TestFlagDefinitionsWithTimeoutExceeded(t *testing.T) {
+
+	// create buffer to write logs to
+	var buf bytes.Buffer
+
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if strings.HasPrefix(r.URL.Path, "/decide") {
+			w.Write([]byte(fixture("test-decide-v2.json")))
+		} else if strings.HasPrefix(r.URL.Path, "/api/feature_flag/local_evaluation") {
+			time.Sleep(11 * time.Second)
+			w.Write([]byte(fixture("feature_flag/test-flag-group-properties.json")))
+		} else if strings.HasPrefix(r.URL.Path, "/batch/") {
+			// Ignore batch requests
+		} else {
+			t.Error("Unknown request made by library")
+		}
+	}))
+	defer server.Close()
+
+	client, _ := NewWithConfig("Csyjlnlun3OzyNJAafdlv", Config{
+		PersonalApiKey:            "some very secret key",
+		Endpoint:                  server.URL,
+		FeatureFlagRequestTimeout: 10 * time.Millisecond,
+		Logger:                    StdLogger(log.New(&buf, "posthog-test", log.LstdFlags)),
+	})
+	defer client.Close()
+
+	_, err := client.IsFeatureEnabled(
+		FeatureFlagPayload{
+			Key:        "enabled-flag",
+			DistinctId: "-",
+		},
+	)
+	if err != nil {
+		t.Error("Unexpected error")
+	}
+
+	output := buf.String()
+	if !strings.Contains(output, "Unable to fetch feature flags") {
+		t.Error("Expected error fetching flags")
+	}
+
+	if !strings.Contains(output, "context deadline exceeded") {
+		t.Error("Expected timeout error fetching flags")
+	}
+}

featureflags.go

@@ -245,7 +245,7 @@ func (poller *FeatureFlagsPoller) GetFeatureFlag(flagConfig FeatureFlagPayload)
 
 		result, err = poller.getFeatureFlagVariant(featureFlag, flagConfig.Key, flagConfig.DistinctId, flagConfig.Groups, flagConfig.PersonProperties, flagConfig.GroupProperties)
 		if err != nil {
-			return nil, nil
+			return nil, err
 		}
 	}
 
@@ -897,6 +897,9 @@ func (poller *FeatureFlagsPoller) getFeatureFlagVariants(distinctId string, grou
 	defer cancel()
 	if err != nil || res.StatusCode != http.StatusOK {
 		errorMessage = "Error calling /decide/"
+		if err != nil {
+			errorMessage += " - " + err.Error()
+		}
 		poller.Errorf(errorMessage)
 		return nil, errors.New(errorMessage)
 	}

fixtures/feature_flag/test-flag-group-properties.json

@@ -1,5 +1,5 @@
 {
-    "count": 1,
+    "count": 2,
     "next": null,
     "previous": null,
     "flags": [
@@ -28,6 +28,30 @@
             "active": true,
             "is_simple_flag": false,
             "rollout_percentage": null
+        },
+        {
+            "id": 719,
+            "name": "",
+            "key": "simple-flag",
+            "filters": {
+                "groups": [
+                    {
+                        "properties": [
+                            {
+                                "key": "region",
+                                "operator": "exact",
+                                "value": ["USA"],
+                                "type": "person"
+                            }
+                        ],
+                        "rollout_percentage": 100
+                    }
+                ]
+            },
+            "deleted": false,
+            "active": true,
+            "is_simple_flag": true,
+            "rollout_percentage": null
         }
     ],
     "group_type_mapping" : {"0": "company", "1": "project"}