feat: Identity overrides in local evaluation mode (#121)

* feat: Identity overrides in local evaluation mode

client.go

@@ -22,7 +22,8 @@ type Client struct {
  apiKey string
  config config
 
- environment atomic.Value
+ environment atomic.Value
+ identitiesWithOverrides atomic.Value
 
  analyticsProcessor *AnalyticsProcessor
  defaultFlagHandler func(string) (Flag, error)
@@ -138,7 +139,7 @@ func (c *Client) GetIdentityFlags(ctx context.Context, identifier string, traits
 // Returns an array of segments that the given identity is part of.
 func (c *Client) GetIdentitySegments(identifier string, traits []*Trait) ([]*segments.SegmentModel, error) {
  if env, ok := c.environment.Load().(*environments.EnvironmentModel); ok {
- identity := buildIdentityModel(identifier, env.APIKey, traits)
+ identity := c.getIdentityModel(identifier, env.APIKey, traits)
  return flagengine.GetIdentitySegments(env, &identity), nil
  }
  return nil, &FlagsmithClientError{msg: "flagsmith: Local evaluation required to obtain identity segments"}
@@ -214,7 +215,7 @@ func (c *Client) getIdentityFlagsFromEnvironment(identifier string, traits []*Tr
  if !ok {
  return Flags{}, fmt.Errorf("flagsmith: local environment has not yet been updated")
  }
- identity := buildIdentityModel(identifier, env.APIKey, traits)
+ identity := c.getIdentityModel(identifier, env.APIKey, traits)
  featureStates := flagengine.GetIdentityFeatureStates(env, &identity)
  flags := makeFlagsFromFeatureStates(
  featureStates,
@@ -276,15 +277,28 @@ func (c *Client) UpdateEnvironment(ctx context.Context) error {
  return errors.New(e["detail"])
  }
  c.environment.Store(&env)
+ identitiesWithOverrides := make(map[string]identities.IdentityModel)
+ for _, id := range env.IdentityOverrides {
+ identitiesWithOverrides[id.Identifier] = *id
+ }
+ c.identitiesWithOverrides.Store(identitiesWithOverrides)
 
  return nil
 }
 
-func buildIdentityModel(identifier string, apiKey string, traits []*Trait) identities.IdentityModel {
+func (c *Client) getIdentityModel(identifier string, apiKey string, traits []*Trait) identities.IdentityModel {
  identityTraits := make([]*TraitModel, len(traits))
  for i, trait := range traits {
  identityTraits[i] = trait.ToTraitModel()
  }
+
+ identitiesWithOverrides, _ := c.identitiesWithOverrides.Load().(map[string]identities.IdentityModel)
+ identity, ok := identitiesWithOverrides[identifier]
+ if ok {
+ identity.IdentityTraits = identityTraits
+ return identity
+ }
+
  return identities.IdentityModel{
  Identifier: identifier,
  IdentityTraits: identityTraits,

client_test.go

@@ -244,6 +244,32 @@ func TestGetIdentityFlagsUseslocalEnvironmentWhenAvailable(t *testing.T) {
  assert.Equal(t, fixtures.Feature1Value, allFlags[0].Value)
 }
 
+func TestGetIdentityFlagsUseslocalOverridesWhenAvailable(t *testing.T) {
+ // Given
+ ctx := context.Background()
+ server := httptest.NewServer(http.HandlerFunc(fixtures.EnvironmentDocumentHandler))
+ defer server.Close()
+ // When
+ client := flagsmith.NewClient(fixtures.EnvironmentAPIKey, flagsmith.WithLocalEvaluation(ctx),
+ flagsmith.WithBaseURL(server.URL+"/api/v1/"))
+ err := client.UpdateEnvironment(ctx)
+
+ // Then
+ assert.NoError(t, err)
+
+ flags, err := client.GetIdentityFlags(ctx, "overridden-id", nil)
+
+ assert.NoError(t, err)
+
+ allFlags := flags.AllFlags()
+
+ assert.Equal(t, 1, len(allFlags))
+
+ assert.Equal(t, fixtures.Feature1Name, allFlags[0].FeatureName)
+ assert.Equal(t, fixtures.Feature1ID, allFlags[0].FeatureID)
+ assert.Equal(t, fixtures.Feature1OverriddenValue, allFlags[0].Value)
+}
+
 func TestGetIdentityFlagsCallsAPIWhenLocalEnvironmentNotAvailableWithTraits(t *testing.T) {
  // Given
  ctx := context.Background()

fixtures/environment.json

@@ -54,5 +54,30 @@
  "segment_id": null,
  "enabled": true
  }
+ ],
+ "identity_overrides": [
+ {
+ "identifier": "overridden-id",
+ "identity_uuid": "0f21cde8-63c5-4e50-baca-87897fa6cd01",
+ "created_date": "2019-08-27T14:53:45.698555Z",
+ "updated_at": "2023-07-14 16:12:00.000000",
+ "environment_api_key": "B62qaMZNwfiqT76p38ggrQ",
+ "identity_features": [
+ {
+ "id": 1,
+ "feature": {
+ "id": 1,
+ "name": "feature_1",
+ "type": "STANDARD"
+ },
+ "featurestate_uuid": "1bddb9a5-7e59-42c6-9be9-625fa369749f",
+ "feature_state_value": "some-overridden-value",
+ "enabled": false,
+ "environment": 1,
+ "identity": null,
+ "feature_segment": null
+ }
+ ]
+ }
  ]
-}
+}

fixtures/fixture.go

@@ -11,6 +11,8 @@ const Feature1Value = "some_value"
 const Feature1Name = "feature_1"
 const Feature1ID = 1
 
+const Feature1OverriddenValue = "some-overridden-value"
+
 const EnvironmentJson = `
 {
  "api_key": "B62qaMZNwfiqT76p38ggrQ",
@@ -58,7 +60,32 @@ const EnvironmentJson = `
  },
  "segment_id": null,
  "enabled": true
- }]
+ }],
+ "identity_overrides": [
+ {
+ "identifier": "overridden-id",
+ "identity_uuid": "0f21cde8-63c5-4e50-baca-87897fa6cd01",
+ "created_date": "2019-08-27T14:53:45.698555Z",
+ "updated_at": "2023-07-14 16:12:00.000000",
+ "environment_api_key": "B62qaMZNwfiqT76p38ggrQ",
+ "identity_features": [
+ {
+ "id": 1,
+ "feature": {
+ "id": 1,
+ "name": "feature_1",
+ "type": "STANDARD"
+ },
+ "featurestate_uuid": "1bddb9a5-7e59-42c6-9be9-625fa369749f",
+ "feature_state_value": "some-overridden-value",
+ "enabled": false,
+ "environment": 1,
+ "identity": null,
+ "feature_segment": null
+ }
+ ]
+ }
+ ]
 }
 `
 

flagengine/environments/models.go

@@ -1,19 +1,15 @@
 package environments
 
 import (
- "github.com/Flagsmith/flagsmith-go-client/v3/flagengine/environments/integrations"
  "github.com/Flagsmith/flagsmith-go-client/v3/flagengine/features"
+ "github.com/Flagsmith/flagsmith-go-client/v3/flagengine/identities"
  "github.com/Flagsmith/flagsmith-go-client/v3/flagengine/projects"
 )
 
 type EnvironmentModel struct {
- ID int `json:"id"`
- APIKey string `json:"api_key"`
- Project *projects.ProjectModel `json:"project"`
- FeatureStates []*features.FeatureStateModel `json:"feature_states"`
-
- AmplitudeConfig *integrations.IntegrationModel `json:"amplitude_config"`
- SegmentConfig *integrations.IntegrationModel `json:"segment_config"`
- MixpanelConfig *integrations.IntegrationModel `json:"mixpanel_config"`
- HeapConfig *integrations.IntegrationModel `json:"heap_config"`
+ ID int `json:"id"`
+ APIKey string `json:"api_key"`
+ Project *projects.ProjectModel `json:"project"`
+ FeatureStates []*features.FeatureStateModel `json:"feature_states"`
+ IdentityOverrides []*identities.IdentityModel `json:"identity_overrides"`
 }