[ffs] - Allow setting initial feature flag values

.licenserc.json

@@ -28,6 +28,10 @@
       "# Copyright The OpenTelemetry Authors",
       "# SPDX-License-Identifier: Apache-2.0"
     ],
+    "**/*.sql": [
+      "-- Copyright The OpenTelemetry Authors",
+      "-- SPDX-License-Identifier: Apache-2.0"
+    ],
     "**/{Dockerfile,Makefile}": [
       "# Copyright The OpenTelemetry Authors",
       "# SPDX-License-Identifier: Apache-2.0"

CHANGELOG.md

@@ -13,6 +13,8 @@ release.
   ([#1313](https://github.com/open-telemetry/opentelemetry-demo/pull/1313))
 * [accountingservice] Update dependencies and semconv
 * ([#1316](https://github.com/open-telemetry/opentelemetry-demo/pull/1316))
+* [featureflagservice] Allow setting initial feature flag values
+  ([#1319](https://github.com/open-telemetry/opentelemetry-demo/pull/1319))
 
 ## 1.7.0
 

docker-compose.yml

@@ -552,6 +552,9 @@ services:
       - POSTGRES_USER=ffs
       - POSTGRES_DB=ffs
       - POSTGRES_PASSWORD=ffs
+    volumes:
+      - ./src/ffs_postgres/10-ffs_schema.sql:/docker-entrypoint-initdb.d/10-ffs_schema.sql
+      - ./src/ffs_postgres/20-ffs_data.sql:/docker-entrypoint-initdb.d/20-ffs_data.sql
     healthcheck:
       test: ["CMD-SHELL", "pg_isready -d ffs -U ffs"]
       interval: 10s

pb/demo.proto

@@ -14,8 +14,6 @@
 
 syntax = "proto3";
 
-import "google/protobuf/timestamp.proto";
-
 package oteldemo;
 
 option go_package = "genproto/oteldemo";
@@ -277,8 +275,6 @@ message Flag {
   string name = 1;
   string description = 2;
   bool enabled = 3;
-  google.protobuf.Timestamp created_at = 4;
-  google.protobuf.Timestamp updated_at = 5;
 }
 
 message GetFlagRequest {

src/featureflagservice/lib/featureflagservice/feature_flags.ex

@@ -35,14 +35,14 @@ defmodule Featureflagservice.FeatureFlags do
 
   ## Examples
 
-      iex> get_feature_flag!(123)
+      iex> get_feature_flag!(foo)
       %FeatureFlag{}
 
-      iex> get_feature_flag!(456)
+      iex> get_feature_flag!(bar)
       ** (Ecto.NoResultsError)
 
   """
-  def get_feature_flag!(id), do: Repo.get!(FeatureFlag, id)
+  def get_feature_flag!(name), do: Repo.get!(FeatureFlag, name)
 
   @doc """
   Gets a single feature_flag by name.

src/featureflagservice/lib/featureflagservice/feature_flags/feature_flag.ex

@@ -5,12 +5,12 @@ defmodule Featureflagservice.FeatureFlags.FeatureFlag do
   use Ecto.Schema
   import Ecto.Changeset
 
-  schema "featureflags" do
+  @primary_key {:name, :string, autogenerate: false}
+  @derive {Phoenix.Param, key: :name}
+
+  schema "featureflags"  do
     field :description, :string
     field :enabled, :float, default: 0.0
-    field :name, :string
-
-    timestamps()
   end
 
   @doc false

src/featureflagservice/src/ffs_service.erl

@@ -34,9 +34,7 @@ get_flag(Ctx, #{name := Name}) ->
       {grpc_error, {?GRPC_STATUS_NOT_FOUND, <<"the requested feature flag does not exist">>}};
     #{'__struct__' := 'Elixir.Featureflagservice.FeatureFlags.FeatureFlag',
       description := Description,
-      enabled := Enabled,
-      inserted_at := CreatedAt,
-      updated_at := UpdatedAt
+      enabled := Enabled
     } ->
       RandomNumber = rand:uniform(100), % Generate a random number between 0 and 100
       Probability = trunc(Enabled * 100), % Convert the Enabled value to a percentage
@@ -46,15 +44,9 @@ get_flag(Ctx, #{name := Name}) ->
       ?set_attribute('app.featureflag.raw_value', Enabled),
       ?set_attribute('app.featureflag.enabled', FlagEnabledValue),
 
-      {ok, Epoch} = 'Elixir.NaiveDateTime':from_erl({{1970, 1, 1}, {0, 0, 0}}),
-      CreatedAtSeconds = 'Elixir.NaiveDateTime':diff(CreatedAt, Epoch),
-      UpdatedAtSeconds = 'Elixir.NaiveDateTime':diff(UpdatedAt, Epoch),
-
       Flag = #{name => Name,
         description => Description,
-        enabled => FlagEnabledValue,
-        created_at => #{seconds => CreatedAtSeconds, nanos => 0},
-        updated_at => #{seconds => UpdatedAtSeconds, nanos => 0}},
+        enabled => FlagEnabledValue},
 
       {ok, #{flag => Flag}, Ctx}
   end.

src/ffs_postgres/10-ffs_schema.sql

@@ -0,0 +1,13 @@
+-- Copyright The OpenTelemetry Authors
+-- SPDX-License-Identifier: Apache-2.0
+
+CREATE TABLE public.featureflags (
+    name character varying(255),
+    description character varying(255),
+    enabled double precision DEFAULT 0.0 NOT NULL
+);
+
+ALTER TABLE ONLY public.featureflags ADD CONSTRAINT featureflags_pkey PRIMARY KEY (name);
+
+CREATE UNIQUE INDEX featureflags_name_index ON public.featureflags USING btree (name);
+

src/ffs_postgres/20-ffs_data.sql

@@ -0,0 +1,15 @@
+-- Copyright The OpenTelemetry Authors
+-- SPDX-License-Identifier: Apache-2.0
+
+-- Feature Flags created and initialized on startup
+--     'enabled' is a decimal value between 0 and 1 (inclusive)
+--     0.0 is always disabled
+--     1.0 is always enabled
+--     All values between set a percentage chance on each request
+--     example: 0.55 is enabled 55% of the time
+INSERT INTO public.featureflags (name, description, enabled)
+VALUES
+    ('productCatalogFailure', 'Fail product catalog service on a specific product', 0),
+    ('recommendationCache', 'Cache recommendations', 0),
+    ('adServiceFailure', 'Fail ad service requests sporadically', 0),
+    ('cartServiceFailure', 'Fail cart service requests sporadically', 0);