Update federation plugin (#2876)

* update 2.7 impl, add missing 2.6 support

* address feedback

* go fmt

api/generate.go

@@ -27,14 +27,17 @@ func Generate(cfg *config.Config, option ...Option) error {
 	if cfg.Federation.IsDefined() {
 		if cfg.Federation.Version == 0 { // default to using the user's choice of version, but if unset, try to sort out which federation version to use
 			urlRegex := regexp.MustCompile(`(?s)@link.*\(.*url:.*?"(.*?)"[^)]+\)`) // regex to grab the url of a link directive, should it exist
-
+			versionRegex := regexp.MustCompile(`v(\d+).(\d+)$`)                    // regex to grab the version number from a url
 			// check the sources, and if one is marked as federation v2, we mark the entirety to be generated using that format
 			for _, v := range cfg.Sources {
 				cfg.Federation.Version = 1
 				urlString := urlRegex.FindStringSubmatch(v.Input)
-				if urlString != nil && urlString[1] == "https://specs.apollo.dev/federation/v2.0" {
-					cfg.Federation.Version = 2
-					break
+				if urlString != nil && urlString[1] == "https://specs.apollo.dev/federation/v2.7" {
+					matches := versionRegex.FindStringSubmatch(urlString[1])
+					if matches[1] == "2" {
+						cfg.Federation.Version = 2
+						break
+					}
 				}
 			}
 		}

api/testdata/federation2/graph/schema.graphqls

@@ -2,7 +2,7 @@
 #
 # https://gqlgen.com/getting-started/
 extend schema
-  @link(url: "https://specs.apollo.dev/federation/v2.0",
+  @link(url: "https://specs.apollo.dev/federation/v2.7",
         import: ["@key", "@shareable", "@provides", "@external", "@tag", "@extends", "@override", "@inaccessible"])
 
 type Todo {

plugin/federation/federation.go

@@ -62,6 +62,9 @@ func (f *federation) MutateConfig(cfg *config.Config) error {
 		"federation__Scope": {
 			Model: config.StringList{"github.com/99designs/gqlgen/graphql.String"},
 		},
+		"federation__Policy": {
+			Model: config.StringList{"github.com/99designs/gqlgen/graphql.String"},
+		},
 	}
 
 	for typeName, entry := range builtins {
@@ -85,6 +88,7 @@ func (f *federation) MutateConfig(cfg *config.Config) error {
 		cfg.Directives["inaccessible"] = config.DirectiveConfig{SkipRuntime: true}
 		cfg.Directives["authenticated"] = config.DirectiveConfig{SkipRuntime: true}
 		cfg.Directives["requiresScopes"] = config.DirectiveConfig{SkipRuntime: true}
+		cfg.Directives["policy"] = config.DirectiveConfig{SkipRuntime: true}
 		cfg.Directives["interfaceObject"] = config.DirectiveConfig{SkipRuntime: true}
 		cfg.Directives["composeDirective"] = config.DirectiveConfig{SkipRuntime: true}
 	}
@@ -126,7 +130,13 @@ func (f *federation) InjectSourceEarly() *ast.Source {
 	  | UNION
 	directive @interfaceObject on OBJECT
 	directive @link(import: [String!], url: String!) repeatable on SCHEMA
-	directive @override(from: String!) on FIELD_DEFINITION
+	directive @override(from: String!, label: String) on FIELD_DEFINITION
+	directive @policy(policies: [[federation__Policy!]!]!) on 
+	  | FIELD_DEFINITION
+	  | OBJECT
+	  | INTERFACE
+	  | SCALAR
+	  | ENUM
 	directive @provides(fields: FieldSet!) on FIELD_DEFINITION
 	directive @requires(fields: FieldSet!) on FIELD_DEFINITION
 	directive @requiresScopes(scopes: [[federation__Scope!]!]!) on 
@@ -149,6 +159,7 @@ func (f *federation) InjectSourceEarly() *ast.Source {
 	  | UNION
 	scalar _Any
 	scalar FieldSet
+	scalar federation__Policy
 	scalar federation__Scope
 `
 	}

plugin/federation/testdata/federation2/federation2.graphql

@@ -1,13 +1,13 @@
 extend schema
-  @link(url: "https://specs.apollo.dev/federation/v2.3",
-        import: ["@key", "@shareable", "@provides", "@external", "@tag", "@extends", "@override", "@inaccessible", "@interfaceObject"])
+  @link(url: "https://specs.apollo.dev/federation/v2.7",
+        import: ["@key", "@shareable", "@provides", "@external", "@tag", "@extends", "@override", "@inaccessible", "@interfaceObject", "@policy"])
 
 schema {
     query: CustomQuery
 }
 
 type Hello @key(fields:"name", resolvable: false) {
-  name: String!
+    name: String! @override(from: "old-service", label: "percent(5)")
 }
 
 type World @key(fields: "foo bar", resolvable: false) {
@@ -21,5 +21,5 @@ extend type ExternalExtension @key(fields: "  upc    ") {
 }
 
 type CustomQuery {
-  hello: Hello!
+    hello: Hello!
 }

plugin/federation/testdata/multi/multi.graphqls

@@ -1,5 +1,5 @@
 extend schema
-  @link(url: "https://specs.apollo.dev/federation/v2.3",
+  @link(url: "https://specs.apollo.dev/federation/v2.7",
         import: ["@key"])
 
 directive @entityResolver(multi: Boolean) on OBJECT