feat: flagd-web provider (open-feature#142)

Signed-off-by: James-Milligan <james@omnant.co.uk>
Co-authored-by: Todd Baert <toddbaert@gmail.com>

Signed-off-by: James-Milligan <james@omnant.co.uk>
Co-authored-by: James-Milligan <james@omnant.co.uk>

Author: toddbaert

.github/workflows/ci.yml

@@ -12,6 +12,8 @@ jobs:
       - uses: actions/checkout@v3
         with:
           fetch-depth: 0
+          submodules: recursive
+
       - uses: bufbuild/buf-setup-action@v1.9.0
         with:
           version: '1.1.1'

.github/workflows/release-please.yml

@@ -20,6 +20,10 @@ jobs:
       - name: Checkout Repository
         if: ${{ steps.release.outputs.releases_created }}
         uses: actions/checkout@v3
+        with:
+          fetch-depth: 0
+          submodules: recursive
+
       - uses: bufbuild/buf-setup-action@v1.9.0
         with:
           version: "1.1.1"

.gitignore

@@ -40,3 +40,8 @@ Thumbs.db
 
 # generated files
 proto
+
+
+# yalc stuff
+.yalc
+yalc.lock

.gitmodules

@@ -1,3 +1,6 @@
 [submodule "libs/providers/flagd/schemas"]
 	path = libs/providers/flagd/schemas
-	url = https://github.com/open-feature/schemas
+	url = https://github.com/open-feature/schemas.git
+[submodule "libs/providers/flagd-web/schemas"]
+	path = libs/providers/flagd-web/schemas
+	url = https://github.com/open-feature/schemas.git

.prettierrc

@@ -1,3 +1,4 @@
 {
+  "printWidth": 120,
   "singleQuote": true
 }

.release-please-manifest.json

@@ -1,5 +1,6 @@
 {
   "libs/hooks/open-telemetry": "5.0.0",
   "libs/providers/go-feature-flag": "0.5.0",
-  "libs/providers/flagd": "0.7.0"
+  "libs/providers/flagd": "0.7.0",
+  "libs/providers/flagd-web": "0.1.0"
 }

libs/hooks/open-telemetry/babel.config.json

@@ -1,3 +1,3 @@
 {
-  "presets": ["minify"]
+  "presets": [["minify", { "builtIns": false }]]
 }

libs/providers/flagd-web/.babelrc

@@ -0,0 +1,10 @@
+{
+  "presets": [
+    [
+      "@nrwl/web/babel",
+      {
+        "useBuiltIns": "usage"
+      }
+    ]
+  ]
+}

libs/providers/flagd-web/.eslintrc.json

@@ -0,0 +1,18 @@
+{
+  "extends": ["../../../.eslintrc.json"],
+  "ignorePatterns": ["!**/*"],
+  "overrides": [
+    {
+      "files": ["*.ts", "*.tsx", "*.js", "*.jsx"],
+      "rules": {}
+    },
+    {
+      "files": ["*.ts", "*.tsx"],
+      "rules": {}
+    },
+    {
+      "files": ["*.js", "*.jsx"],
+      "rules": {}
+    }
+  ]
+}

libs/providers/flagd-web/README.md

@@ -0,0 +1,72 @@
+# flagd-web Provider for OpenFeature
+
+![Experimental](https://img.shields.io/badge/experimental-breaking%20changes%20allowed-yellow)
+
+A feature flag daemon with a Unix philosophy.
+
+## Installation
+
+:warning: This provider requires an experimental version of the JS-SDK:
+
+```
+npm i @openfeature/js-sdk@1.0.99-experimental-55bf085fbdec8a76753b02b3efee8bec3eac53c0
+```
+
+```sh
+npm install @openfeature/flagd-web-provider
+```
+
+## Usage
+
+The `FlagdWebProvider` communicates with flagd via the [connect protocol](https://buf.build/blog/connect-a-better-grpc).
+
+### Reconnection
+
+If the connection to the flagd instance fails, the provider will attempt to reconnect with an exponential back-off. The `maxDelay` and `maxRetries` can be specified to customize reconnect behavior.
+
+### Event streaming
+
+The `FlagdWebProvider` can be configured to receive events for flag changes. Combined with the event API in the JS SDK, this allows for subscription to flag value changes in clients.
+
+### Caching
+
+The `FlagdWebProvider` will cache resolve flag values based on the associated flag-key and context. Values are cached in localstorage. A TTL for cached values can be specified. If [event-streaming](#event-streaming) is enabled, the cache will be invalidated intelligently when flag configuration change events are received.
+
+### Available options
+
+| Option name    | Type    | Default   | Description                                                                                                        |
+| -------------- | ------- | --------- | ------------------------------------------------------------------------------------------------------------------ |
+| host           | string  | localhost | sets the host used to connect to the flagd instance                                                                |
+| port           | number  | 8013      | sets the port used to connect to the flagd instance                                                                |
+| tls            | boolean | false     | when set to true the provider will attempt to connect to flagd via https                                           |
+| maxRetries     | number  | 0         | sets the maximum number of retries for a connection to be made to the flagd instance, a value of 0 means unlimited |
+| maxDelay       | number  | 60000     | sets the maximum time in ms to wait between reconnect intervals                                                    |
+| caching        | boolean | true      | when set to true the provider will use client side caching                                                         |
+| cacheTtl       | number  | 300         | sets the timeout in ms for items in the cache, a value of 0 disables the ttl                                       |
+| eventStreaming | boolean | true      | enables or disables streaming and event features.                                                                  |
+
+## Example
+
+```typescript
+OpenFeature.setProvider(
+  new FlagdWebProvider({
+    host: 'localhost',
+    port: 8013,
+    tls: true,
+    maxRetries: 10,
+    maxDelay: 30000,
+    cache: true,
+    cacheTTL: 60000,
+  })
+);
+```
+
+## Building
+
+Run `npx nx package providers-flagd-web` to build the library.
+
+> NOTE: [Buf](https://docs.buf.build/installation) must be installed to build locally.
+
+## Running unit tests
+
+Run `npx nx test providers-flagd-web` to execute the unit tests via [Jest](https://jestjs.io).