Few changes in GraphQL part:

README.markdown

@@ -54,11 +54,18 @@ This sample app has several key components:
 
 Additional libraries used:
 
-* `spray-json` for JSON processing.
+* `play-json` for JSON processing.
 * `zio-logging` for logging.
 * `zio-config` for typesafe configuration.
 * `zio-test` for testing.
 
+###GraphQL
+
+During initialization step, there is a possibility to add GraphQL endpoint managed by Caliban library. 
+It adds two endpoints to the api: `/api/graphql` which is responsible for GraphQL queries and `/graphiql` with simple 
+GraphiQL console to play with the API.
+
+To try out this feature open the browser http://localhost:8080/graphiql
 
 Template license
 ----------------

src/main/g8/src/main/resources/$if(add_caliban_endpoint.truthy)$graphql$endif$/graphiql.html

@@ -108,11 +108,7 @@
     // use fetch, and could instead implement graphQLFetcher however you like,
     // as long as it returns a Promise or Observable.
     function graphQLFetcher(graphQLParams) {
-        // When working locally, the example expects a GraphQL server at the path /graphql.
-        // In a PR preview, it connects to the Star Wars API externally.
-        // Change this to point wherever you host your GraphQL server.
-        const isDev = !window.location.hostname.match(/(^|\.)netlify\.com\$|(^|\.)graphql\.org\$/)
-        const api = isDev ? '/api/graphql' : 'https://swapi.graph.cool/'
+        const api = '/api/graphql'
         const token = localStorage.getItem('Authorization')
         return fetch(api, {
             method: 'post',

src/main/g8/src/main/scala/$package$/api/graphql/$if(add_caliban_endpoint.truthy)$GraphQLApi.scala$endif$

@@ -34,29 +34,40 @@ object GraphQLApi extends GenericSchema[Any] {
 
   case class ItemName(name: String)
   case class ItemPrice(price: BigDecimal)
+  case class ItemInput(name: String, price: BigDecimal)
 
   case class Queries(
     @GQLDescription("Find items by name")
-    item: ItemName => Task[List[Item]],
+    itemByName: ItemName => Task[List[Item]],
     @GQLDescription("Find items cheaper than specified price")
-    cheaperThan: ItemPrice => Task[List[Item]]
+    cheaperThan: ItemPrice => Task[List[Item]],
+    @GQLDescription("Get all items")
+    allItems: Task[List[Item]],
+    @GQLDescription("Get item by ID")
+    item: ItemId => Task[Option[Item]]
   )
 
   def adaptError(e: DomainError): Throwable = e match {
     case RepositoryError(cause) => cause
     case ValidationError(msg)   => new Exception(msg)
   }
 
-  case class Mutations(deleteItem: ItemId => ZIO[Any, Throwable, Unit])
+  case class Mutations(
+    addItem: ItemInput => Task[ItemId],
+    deleteItem: ItemId => Task[Unit])
 
   def api(repository: ItemRepository): GraphQL[Console with Clock] =
     graphQL(
       RootResolver(
         Queries(
           args => ApplicationService.getItemByName(args.name).mapError(adaptError).provide(repository),
-          args => ApplicationService.getItemsCheaperThan(args.price).mapError(adaptError).provide(repository)
+          args => ApplicationService.getItemsCheaperThan(args.price).mapError(adaptError).provide(repository),
+          ApplicationService.getItems.mapError(adaptError).provide(repository),
+          id => ApplicationService.getItem(id).mapError(adaptError).provide(repository)
         ),
-        Mutations(id => ApplicationService.deleteItem(id).provide(repository).mapError(e => new Throwable("")))
+        Mutations(
+          item => ApplicationService.addItem(item.name, item.price).mapError(_.asThrowable).provide(repository),
+          id => ApplicationService.deleteItem(id).mapError(e => new Throwable(""))).provide(repository)
       )
     ) @@
       maxFields(200) @@               // query analyzer that limit query fields