easier directives for sangria (#250)

Author: yanns

implementations/sangria/README.md

@@ -2,16 +2,24 @@
 
 Implementation of a federated subgraph based on the scala library [sangria](https://sangria-graphql.github.io/).
 
+## Practical information
 
-# Usage
+There are several ways to define a GraphQL schema with sangria.
+Here we are using a code first schema generation.
+And we are splitting the domain model and the GraphQL schema. This ensures separation of concerns.
 
-## Starting the GraphQL server
+On the other hand, this approach needs more lines of code.
+If your goal is to have less lines of code, you could mix the domain and the GraphQL and use the [automatic derivation](https://sangria-graphql.github.io/learn/#macro-based-graphql-type-derivation).
+
+## Usage
+
+### Starting the GraphQL server
 
 ```
 sbt run
 ```
 
-## Printing the GraphQL schema (SQL)
+### Printing the GraphQL schema (SQL)
 
 ```
 sbt "run printSchema"

implementations/sangria/build.sbt

@@ -1,13 +1,13 @@
 import sbt._
 
 version := "1.0.0"
-scalaVersion := "2.13.9"
+scalaVersion := "2.13.10"
 
 val http4sVersion = "1.0.0-M37"
 val circeVersion = "0.14.3"
 
 libraryDependencies ++= List(
-  "org.sangria-graphql" %% "sangria-federated" % "0.4.0",
+  "org.sangria-graphql" %% "sangria-federated" % "0.5.0",
   "org.sangria-graphql" %% "sangria-circe" % "1.3.2",
   "org.http4s" %% "http4s-ember-server" % http4sVersion,
   "org.http4s" %% "http4s-dsl" % http4sVersion,

implementations/sangria/project/build.properties

@@ -1 +1 @@
-sbt.version=1.6.2
+sbt.version=1.7.2

implementations/sangria/src/main/scala/graphql/Directives.scala

@@ -1,11 +1,10 @@
 package graphql
 
-import graphql.Directives.{Inaccessible, Provides, Shareable, Tag}
 import graphql.UserGraphQLSchema.UserType
 import io.circe.Json
 import io.circe.generic.semiauto._
 import model._
-import sangria.federation.v2.Directives.Key
+import sangria.federation.v2.Directives._
 import sangria.federation.v2.{Decoder, EntityResolver}
 import sangria.schema._
 
@@ -17,16 +16,14 @@ object ProductGraphQLSchema {
     )
   )
 
-  private val ProductDimensionType: ObjectType[Unit, ProductDimension] = Shareable(
-    ObjectType(
-      "ProductDimension",
-      fields = fields[Unit, ProductDimension](
-        Field("size", OptionType(StringType), resolve = _.value.size),
-        Field("weight", OptionType(FloatType), resolve = _.value.weight),
-        Inaccessible(Field("unit", OptionType(StringType), resolve = _.value.unit))
-      )
+  private val ProductDimensionType: ObjectType[Unit, ProductDimension] = ObjectType(
+    "ProductDimension",
+    fields = fields[Unit, ProductDimension](
+      Field("size", OptionType(StringType), resolve = _.value.size),
+      Field("weight", OptionType(FloatType), resolve = _.value.weight),
+      Field("unit", OptionType(StringType), resolve = _.value.unit, astDirectives = Vector(Inaccessible))
     )
-  )
+  ).withDirective(Shareable)
 
   private val CaseStudyType: ObjectType[Unit, CaseStudy] = ObjectType(
     "CaseStudy",
@@ -42,7 +39,7 @@ object ProductGraphQLSchema {
       Field("study", CaseStudyType, resolve = _.value.study),
       Field("outcome", OptionType(StringType), resolve = _.value.outcome)
     )
-  ).copy(astDirectives = Vector(Key("study { caseNumber }")))
+  ).withDirective(Key("study { caseNumber }"))
 
   private val ProductType: ObjectType[Unit, Product] = ObjectType(
     "Product",
@@ -52,16 +49,19 @@ object ProductGraphQLSchema {
       Field("package", OptionType(StringType), resolve = _.value.`package`),
       Field("variation", OptionType(ProductVariationType), resolve = _.value.variation),
       Field("dimensions", OptionType(ProductDimensionType), resolve = _.value.dimensions),
-      Provides("totalProductsCreated")(Field("createdBy", OptionType(UserType), resolve = _.value.createdBy)),
-      Tag("internal")(Field("notes", OptionType(StringType), resolve = _.value.notes)),
+      Field(
+        "createdBy",
+        OptionType(UserType),
+        resolve = _.value.createdBy,
+        astDirectives = Vector(Provides("totalProductsCreated"))
+      ),
+      Field("notes", OptionType(StringType), resolve = _.value.notes, astDirectives = Vector(Tag("internal"))),
       Field("research", ListType(ProductResearchType), resolve = _.value.research)
     )
-  ).copy(astDirectives =
-    Vector(
-      Key("id"),
-      Key("sku package"),
-      Key("sku variation { id }")
-    )
+  ).withDirectives(
+    Key("id"),
+    Key("sku package"),
+    Key("sku variation { id }")
   )
 
   private val DeprecatedProductType: ObjectType[Unit, DeprecatedProduct] = ObjectType(
@@ -72,11 +72,7 @@ object ProductGraphQLSchema {
       Field("reason", OptionType(StringType), resolve = _.value.reason),
       Field("createdBy", OptionType(UserType), resolve = _.value.createdBy)
     )
-  ).copy(astDirectives =
-    Vector(
-      Key("sku package")
-    )
-  )
+  ).withDirective(Key("sku package"))
 
   val IdArg: Argument[String] = Argument("id", IDType)
   val SkuArg: Argument[String] = Argument("sku", StringType)

implementations/sangria/src/main/scala/graphql/ProductGraphQLSchema.scala

@@ -1,28 +1,34 @@
 package graphql
 
-import graphql.Directives.{External, Override, Requires}
 import io.circe.Json
 import model.{ID, User}
+import sangria.federation.v2.Directives._
 import sangria.federation.v2.{Decoder, EntityResolver}
-import sangria.federation.v2.Directives.Key
 import sangria.schema._
-import service.UserService
 
 object UserGraphQLSchema {
   // should be "extend", but according to the spec, an extend type can only exist if there is one type:
   // http://spec.graphql.org/draft/#sec-Object-Extensions.Type-Validation
   val UserType: ObjectType[Unit, User] = ObjectType(
     "User",
     fields = fields[Unit, User](
-      External(Field("email", IDType, resolve = _.value.email.value)),
-      Override("users")(Field("name", OptionType(StringType), resolve = _.value.name)),
-      External(Field("yearsOfEmployment", IntType, resolve = _.value.yearsOfEmployment)),
-      External(Field("totalProductsCreated", OptionType(IntType), resolve = _.value.totalProductsCreated)),
-      Requires("totalProductsCreated yearsOfEmployment")(
-        Field("averageProductsCreatedPerYear", OptionType(IntType), resolve = _.value.averageProductsCreatedPerYear)
+      Field("email", IDType, resolve = _.value.email.value, astDirectives = Vector(External)),
+      Field("name", OptionType(StringType), resolve = _.value.name, astDirectives = Vector(Override("users"))),
+      Field("yearsOfEmployment", IntType, resolve = _.value.yearsOfEmployment, astDirectives = Vector(External)),
+      Field(
+        "totalProductsCreated",
+        OptionType(IntType),
+        resolve = _.value.totalProductsCreated,
+        astDirectives = Vector(External)
+      ),
+      Field(
+        "averageProductsCreatedPerYear",
+        OptionType(IntType),
+        resolve = _.value.averageProductsCreatedPerYear,
+        astDirectives = Vector(Requires("totalProductsCreated yearsOfEmployment"))
       )
     )
-  ).copy(astDirectives = Vector(Key("email")))
+  ).withDirective(Key("email"))
 
   implicit val decoder: Decoder[Json, ID] = ID.decoder.decodeJson