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Author: elpete

README.md

@@ -1,3 +1,76 @@
 # Unleash SDK
 
-## Library for interacting with Unleash feature flags
+## Library for interacting with [Unleash](https://www.getunleash.io/) feature flags
+
+### Requirements
+
+Adobe ColdFusion 2018+
+Lucee 5+
+ColdBox 6+
+
+This module takes heavy advantage of ColdBox's async scheduling. There are no plans to make this module work outside of ColdBox.
+
+### Configuration
+
+Here are the settings for the UnleashSDK:
+
+```cfc
+settings = {
+    "appName": getApplicationName(), // Defaults to `this.name` in `Application.cfc`.
+    "instanceId": resolveHostname(), // Attempts to resolve the hostname. "unknown", otherwise.
+    "environment": variables.controller.getSetting( "environment" ),
+    "contextProvider": "DefaultContextProvider@unleashsdk",
+    "apiURL": getSystemSetting( "UNLEASH_API_URL" ),
+    "apiToken": getSystemSetting( "UNLEASH_API_TOKEN" ),
+    "refreshInterval": 10,
+    "metricsInterval": 60
+}
+```
+
+Any of these settings can be overridden inside your `config/ColdBox.cfc`.
+If you don't need to modify the default settings, you can supply your Unleash
+configuration directly through environment variables via `UNLEASH_API_URL` and `UNLEASH_API_TOKEN`.
+
+### Usage
+
+The main usage of the UnleashSDK is checking if a feature flag is enabled. This is done using the `isEnabled` method.
+(There is also a helper `isDisabled` method for your convenience.)
+
+#### `isEnabled`
+
+Evaluates the feature with the current and provided context to determine if it is enabled for the current request.
+
+Returns: `boolean`
+
+| Name              | Type    | Required | Default | Description                                                                                                                          |
+| ----------------- | ------- | -------- | ------- | ------------------------------------------------------------------------------------------------------------------------------------ |
+| name              | string  | true     |         | The name of the feature flag to evaluate                                                                                             |
+| additionalContext | struct  | false    | `{}`    | Any additional context items for this check. This struct will override any duplicate keys in the context from the `ContextProvider`. |
+| defaultValue      | boolean | false    | `false` | The default value to use if the feature does not exist.                                                                              |
+
+### Context and ContextProviders
+
+Context refers to information about the current request that Unleash will use when
+evaluating feature toggles. Context includes the following fields:
+
+```cfc
+context = {
+    "appName"       : getApplicationName(), // Defaults to `this.name` in `Application.cfc`
+    "environment"   : variables.environment, // `controller.getSetting( "environment" )`
+    "userId"        : "",
+    "sessionId"     : getSessionId(), // `session.sessionid`
+    "remoteAddress" : CGI.REMOTE_ADDR,
+    "hostname"      : resolveHostname() // Attempts to resolve the hostname. "unknown", otherwise.
+};
+```
+
+Context is generated using a `ContextProvider` and/or the `context` arguments to `isEnabled`.
+The `context` provided to `isEnabled` will overwrite any duplicate keys in the context
+generated by the `ContextProvider`.
+
+A `ContextProvider` is a component with `getContext()` method. That method should return
+the context fields shown above.
+
+You can register a custom `ContextProvider` by the setting `contextProvider` in your `config/ColdBox.cfc`.
+A custom `ContextProvider` can enabled you to always provide specific user or session information
+for your application without having to pass it in manually each time you call `isEnabled`.