update README.md

README.md

@@ -1,8 +1,11 @@
-# Retrofit Kotlin Result Adapter
+# Retrofit Suspend Kotlin Result Adapter
+
+[![Release](https://jitpack.io/v/yujinyan/retrofit-suspend-result-adapter.svg?style=flat-square)](https://jitpack.io/#User/Repo)
 
 A Retrofit 2 `CallAdapter.Factory` for Kotlin suspend functions that use the standard
 library [`kotlin.Result`](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-result/) as return value. The call
-adapter catches all exceptions so that there is no need to try catch suspend functions at call sites.
+adapter catches network failures / deserialization errors so that there is no need to try catch suspend functions at
+call sites.
 
 Many useful methods are available on the `Result` type. Once [Kotlin allows null-safety operators `?.`, `?:` and `!!`
 on `Result`](https://github.com/Kotlin/KEEP/pull/244), the ergonomics of using this type will be greatly improved.
@@ -42,14 +45,35 @@ lifecycleScope.launch {
 
 ## Failure handler
 
-You can register a default failure handler through the constructor.
+You can register a default failure handler through the constructor. This is a good place for configuring global error
+handling logic.
 
 ```kotlin
 val retrofit = Retrofit.Builder()
-  .baseUrl("https://")
+  .baseUrl("https://example.com")
   .addCallAdapterFactory(SuspendResultCallAdapterFactory {
     report(it)
   })
   .addConverterFactory(MoshiConverterFactory.create(moshi))
   .build()
 ```
+
+## Custom converter for `Result<T>`
+
+If your API returns data wrapped in an "envelop", it may be a good idea to unwrap the data and place it in `Result`
+directly.
+
+Suppose the API response looks like this. You can still use `Result<User>` as return type.
+
+```json
+{
+  "errcode": 0,
+  "data": {
+    "id": 1,
+    "name": "Peter"
+  }
+}
+```
+
+To achieve this, write a custom converter.
+Checkout [CustomConverterTest](src/test/kotlin/me/yujinyan/retrofit/CustomConverterTest.kt) for an example.