feat: ✨ add simple pets and users subgraphs with GQLGen

pets/.gitignore

@@ -0,0 +1,21 @@
+# If you prefer the allow list template instead of the deny list, see community template:
+# https://github.com/github/gitignore/blob/main/community/Golang/Go.AllowList.gitignore
+#
+# Binaries for programs and plugins
+*.exe
+*.exe~
+*.dll
+*.so
+*.dylib
+
+# Test binary, built with `go test -c`
+*.test
+
+# Output of the go coverage tool, specifically when used with LiteIDE
+*.out
+
+# Dependency directories (remove the comment below to include it)
+# vendor/
+
+# Go workspace file
+go.work

pets/go.mod

@@ -0,0 +1,26 @@
+module github.com/Dan6erbond/sitling/pets
+
+go 1.20
+
+require (
+	github.com/99designs/gqlgen v0.17.39
+	github.com/vektah/gqlparser/v2 v2.5.10
+)
+
+require (
+	github.com/agnivade/levenshtein v1.1.1 // indirect
+	github.com/cpuguy83/go-md2man/v2 v2.0.2 // indirect
+	github.com/google/uuid v1.3.0 // indirect
+	github.com/gorilla/websocket v1.5.0 // indirect
+	github.com/hashicorp/golang-lru/v2 v2.0.3 // indirect
+	github.com/mitchellh/mapstructure v1.5.0 // indirect
+	github.com/russross/blackfriday/v2 v2.1.0 // indirect
+	github.com/sosodev/duration v1.1.0 // indirect
+	github.com/urfave/cli/v2 v2.25.5 // indirect
+	github.com/xrash/smetrics v0.0.0-20201216005158-039620a65673 // indirect
+	golang.org/x/mod v0.10.0 // indirect
+	golang.org/x/sys v0.8.0 // indirect
+	golang.org/x/text v0.9.0 // indirect
+	golang.org/x/tools v0.9.3 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)

pets/go.sum

@@ -0,0 +1,47 @@
+github.com/99designs/gqlgen v0.17.39 h1:wPTAyc2fqVjAWT5DsJ21k/lLudgnXzURwbsjVNegFpU=
+github.com/99designs/gqlgen v0.17.39/go.mod h1:b62q1USk82GYIVjC60h02YguAZLqYZtvWml8KkhJps4=
+github.com/agnivade/levenshtein v1.1.1 h1:QY8M92nrzkmr798gCo3kmMyqXFzdQVpxLlGPRBij0P8=
+github.com/agnivade/levenshtein v1.1.1/go.mod h1:veldBMzWxcCG2ZvUTKD2kJNRdCk5hVbJomOvKkmgYbo=
+github.com/andreyvit/diff v0.0.0-20170406064948-c7f18ee00883 h1:bvNMNQO63//z+xNgfBlViaCIJKLlCJ6/fmUseuG0wVQ=
+github.com/arbovm/levenshtein v0.0.0-20160628152529-48b4e1c0c4d0 h1:jfIu9sQUG6Ig+0+Ap1h4unLjW6YQJpKZVmUzxsD4E/Q=
+github.com/arbovm/levenshtein v0.0.0-20160628152529-48b4e1c0c4d0/go.mod h1:t2tdKJDJF9BV14lnkjHmOQgcvEKgtqs5a1N3LNdJhGE=
+github.com/cpuguy83/go-md2man/v2 v2.0.2 h1:p1EgwI/C7NhT0JmVkwCD2ZBK8j4aeHQX2pMHHBfMQ6w=
+github.com/cpuguy83/go-md2man/v2 v2.0.2/go.mod h1:tgQtvFlXSQOSOSIRvRPT7W67SCa46tRHOmNcaadrF8o=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/dgryski/trifles v0.0.0-20200323201526-dd97f9abfb48 h1:fRzb/w+pyskVMQ+UbP35JkH8yB7MYb4q/qhBarqZE6g=
+github.com/dgryski/trifles v0.0.0-20200323201526-dd97f9abfb48/go.mod h1:if7Fbed8SFyPtHLHbg49SI7NAdJiC5WIA09pe59rfAA=
+github.com/google/uuid v1.3.0 h1:t6JiXgmwXMjEs8VusXIJk2BXHsn+wx8BZdTaoZ5fu7I=
+github.com/google/uuid v1.3.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/gorilla/websocket v1.5.0 h1:PPwGk2jz7EePpoHN/+ClbZu8SPxiqlu12wZP/3sWmnc=
+github.com/gorilla/websocket v1.5.0/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
+github.com/hashicorp/golang-lru/v2 v2.0.3 h1:kmRrRLlInXvng0SmLxmQpQkpbYAvcXm7NPDrgxJa9mE=
+github.com/hashicorp/golang-lru/v2 v2.0.3/go.mod h1:QeFd9opnmA6QUJc5vARoKUSoFhyfM2/ZepoAG6RGpeM=
+github.com/mitchellh/mapstructure v1.5.0 h1:jeMsZIYE/09sWLaz43PL7Gy6RuMjD2eJVyuac5Z2hdY=
+github.com/mitchellh/mapstructure v1.5.0/go.mod h1:bFUtVrKA4DC2yAKiSyO/QUcy7e+RRV2QTWOzhPopBRo=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/russross/blackfriday/v2 v2.1.0 h1:JIOH55/0cWyOuilr9/qlrm0BSXldqnqwMsf35Ld67mk=
+github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
+github.com/sergi/go-diff v1.3.1 h1:xkr+Oxo4BOQKmkn/B9eMK0g5Kg/983T9DqqPHwYqD+8=
+github.com/sosodev/duration v1.1.0 h1:kQcaiGbJaIsRqgQy7VGlZrVw1giWO+lDoX3MCPnpVO4=
+github.com/sosodev/duration v1.1.0/go.mod h1:RQIBBX0+fMLc/D9+Jb/fwvVmo0eZvDDEERAikUR6SDg=
+github.com/stretchr/testify v1.8.2 h1:+h33VjcLVPDHtOdpUCuF+7gSuG3yGIftsP1YvFihtJ8=
+github.com/urfave/cli/v2 v2.25.5 h1:d0NIAyhh5shGscroL7ek/Ya9QYQE0KNabJgiUinIQkc=
+github.com/urfave/cli/v2 v2.25.5/go.mod h1:GHupkWPMM0M/sj1a2b4wUrWBPzazNrIjouW6fmdJLxc=
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+github.com/vektah/gqlparser/v2 v2.5.10/go.mod h1:1rCcfwB2ekJofmluGWXMSEnPMZgbxzwj6FaZ/4OT8Cc=
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+github.com/xrash/smetrics v0.0.0-20201216005158-039620a65673/go.mod h1:N3UwUGtsrSj3ccvlPHLoLsHnpR27oXr4ZE984MbSER8=
+golang.org/x/mod v0.10.0 h1:lFO9qtOdlre5W1jxS3r/4szv2/6iXxScdzjoBMXNhYk=
+golang.org/x/mod v0.10.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
+golang.org/x/sync v0.2.0 h1:PUR+T4wwASmuSTYdKjYHI5TD22Wy5ogLU5qZCOLxBrI=
+golang.org/x/sys v0.8.0 h1:EBmGv8NaZBZTWvrbjNoL6HVt+IVy3QDQpJs7VRIw3tU=
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+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v2 v2.4.0 h1:D8xgwECY7CYvx+Y2n4sBz93Jn9JRvxdiyyo8CTfuKaY=
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pets/gqlgen.yml

@@ -0,0 +1,88 @@
+# Where are all the schema files located? globs are supported eg  src/**/*.graphqls
+schema:
+  - graph/*.graphqls
+
+# Where should the generated server code go?
+exec:
+  filename: graph/generated.go
+  package: graph
+
+# Uncomment to enable federation
+federation:
+  filename: graph/federation.go
+  package: graph
+  version: 2
+
+# Where should any generated models go?
+model:
+  filename: graph/model/models_gen.go
+  package: model
+
+# Where should the resolver implementations go?
+resolver:
+  layout: follow-schema
+  dir: graph
+  package: graph
+  filename_template: "{name}.resolvers.go"
+  # Optional: turn on to not generate template comments above resolvers
+  # omit_template_comment: false
+
+# Optional: turn on use ` + "`" + `gqlgen:"fieldName"` + "`" + ` tags in your models
+# struct_tag: json
+
+# Optional: turn on to use []Thing instead of []*Thing
+# omit_slice_element_pointers: false
+
+# Optional: turn on to omit Is<Name>() methods to interface and unions
+# omit_interface_checks : true
+
+# Optional: turn on to skip generation of ComplexityRoot struct content and Complexity function
+# omit_complexity: false
+
+# Optional: turn on to not generate any file notice comments in generated files
+# omit_gqlgen_file_notice: false
+
+# Optional: turn on to exclude the gqlgen version in the generated file notice. No effect if `omit_gqlgen_file_notice` is true.
+# omit_gqlgen_version_in_file_notice: false
+
+# Optional: turn off to make struct-type struct fields not use pointers
+# e.g. type Thing struct { FieldA OtherThing } instead of { FieldA *OtherThing }
+# struct_fields_always_pointers: true
+
+# Optional: turn off to make resolvers return values instead of pointers for structs
+# resolvers_always_return_pointers: true
+
+# Optional: turn on to return pointers instead of values in unmarshalInput
+# return_pointers_in_unmarshalinput: false
+
+# Optional: wrap nullable input fields with Omittable
+# nullable_input_omittable: true
+
+# Optional: set to speed up generation time by not performing a final validation pass.
+# skip_validation: true
+
+# Optional: set to skip running `go mod tidy` when generating server code
+# skip_mod_tidy: true
+
+# gqlgen will search for any type names in the schema in these go packages
+# if they match it will use them, otherwise it will generate them.
+autobind:
+#  - "github.com/Dan6erbond/sitling/pets/graph/model"
+
+# This section declares type mapping between the GraphQL and go type systems
+#
+# The first line in each type will be used as defaults for resolver arguments and
+# modelgen, the others will be allowed when binding to fields. Configure them to
+# your liking
+models:
+  ID:
+    model:
+      - github.com/99designs/gqlgen/graphql.ID
+      - github.com/99designs/gqlgen/graphql.Int
+      - github.com/99designs/gqlgen/graphql.Int64
+      - github.com/99designs/gqlgen/graphql.Int32
+  Int:
+    model:
+      - github.com/99designs/gqlgen/graphql.Int
+      - github.com/99designs/gqlgen/graphql.Int64
+      - github.com/99designs/gqlgen/graphql.Int32

pets/graph/entity.resolvers.go

@@ -0,0 +1,26 @@
+package graph
+
+// This file will be automatically regenerated based on the schema, any resolver implementations
+// will be copied through when generating and any unknown code will be moved to the end.
+// Code generated by github.com/99designs/gqlgen version v0.17.39
+
+import (
+	"context"
+
+	"github.com/Dan6erbond/sitling/pets/graph/model"
+)
+
+// FindPetByID is the resolver for the findPetByID field.
+func (r *entityResolver) FindPetByID(ctx context.Context, id string) (*model.Pet, error) {
+	return &model.Pet{ID: id}, nil
+}
+
+// FindUserByID is the resolver for the findUserByID field.
+func (r *entityResolver) FindUserByID(ctx context.Context, id string) (*model.User, error) {
+	return &model.User{ID: id}, nil
+}
+
+// Entity returns EntityResolver implementation.
+func (r *Resolver) Entity() EntityResolver { return &entityResolver{r} }
+
+type entityResolver struct{ *Resolver }

pets/graph/federation.go

@@ -0,0 +1,224 @@
+// Code generated by github.com/99designs/gqlgen, DO NOT EDIT.
+
+package graph
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"strings"
+	"sync"
+
+	"github.com/99designs/gqlgen/plugin/federation/fedruntime"
+)
+
+var (
+	ErrUnknownType  = errors.New("unknown type")
+	ErrTypeNotFound = errors.New("type not found")
+)
+
+func (ec *executionContext) __resolve__service(ctx context.Context) (fedruntime.Service, error) {
+	if ec.DisableIntrospection {
+		return fedruntime.Service{}, errors.New("federated introspection disabled")
+	}
+
+	var sdl []string
+
+	for _, src := range sources {
+		if src.BuiltIn {
+			continue
+		}
+		sdl = append(sdl, src.Input)
+	}
+
+	return fedruntime.Service{
+		SDL: strings.Join(sdl, "\n"),
+	}, nil
+}
+
+func (ec *executionContext) __resolve_entities(ctx context.Context, representations []map[string]interface{}) []fedruntime.Entity {
+	list := make([]fedruntime.Entity, len(representations))
+
+	repsMap := map[string]struct {
+		i []int
+		r []map[string]interface{}
+	}{}
+
+	// We group entities by typename so that we can parallelize their resolution.
+	// This is particularly helpful when there are entity groups in multi mode.
+	buildRepresentationGroups := func(reps []map[string]interface{}) {
+		for i, rep := range reps {
+			typeName, ok := rep["__typename"].(string)
+			if !ok {
+				// If there is no __typename, we just skip the representation;
+				// we just won't be resolving these unknown types.
+				ec.Error(ctx, errors.New("__typename must be an existing string"))
+				continue
+			}
+
+			_r := repsMap[typeName]
+			_r.i = append(_r.i, i)
+			_r.r = append(_r.r, rep)
+			repsMap[typeName] = _r
+		}
+	}
+
+	isMulti := func(typeName string) bool {
+		switch typeName {
+		default:
+			return false
+		}
+	}
+
+	resolveEntity := func(ctx context.Context, typeName string, rep map[string]interface{}, idx []int, i int) (err error) {
+		// we need to do our own panic handling, because we may be called in a
+		// goroutine, where the usual panic handling can't catch us
+		defer func() {
+			if r := recover(); r != nil {
+				err = ec.Recover(ctx, r)
+			}
+		}()
+
+		switch typeName {
+		case "Pet":
+			resolverName, err := entityResolverNameForPet(ctx, rep)
+			if err != nil {
+				return fmt.Errorf(`finding resolver for Entity "Pet": %w`, err)
+			}
+			switch resolverName {
+
+			case "findPetByID":
+				id0, err := ec.unmarshalNID2string(ctx, rep["id"])
+				if err != nil {
+					return fmt.Errorf(`unmarshalling param 0 for findPetByID(): %w`, err)
+				}
+				entity, err := ec.resolvers.Entity().FindPetByID(ctx, id0)
+				if err != nil {
+					return fmt.Errorf(`resolving Entity "Pet": %w`, err)
+				}
+
+				list[idx[i]] = entity
+				return nil
+			}
+		case "User":
+			resolverName, err := entityResolverNameForUser(ctx, rep)
+			if err != nil {
+				return fmt.Errorf(`finding resolver for Entity "User": %w`, err)
+			}
+			switch resolverName {
+
+			case "findUserByID":
+				id0, err := ec.unmarshalNID2string(ctx, rep["id"])
+				if err != nil {
+					return fmt.Errorf(`unmarshalling param 0 for findUserByID(): %w`, err)
+				}
+				entity, err := ec.resolvers.Entity().FindUserByID(ctx, id0)
+				if err != nil {
+					return fmt.Errorf(`resolving Entity "User": %w`, err)
+				}
+
+				list[idx[i]] = entity
+				return nil
+			}
+
+		}
+		return fmt.Errorf("%w: %s", ErrUnknownType, typeName)
+	}
+
+	resolveManyEntities := func(ctx context.Context, typeName string, reps []map[string]interface{}, idx []int) (err error) {
+		// we need to do our own panic handling, because we may be called in a
+		// goroutine, where the usual panic handling can't catch us
+		defer func() {
+			if r := recover(); r != nil {
+				err = ec.Recover(ctx, r)
+			}
+		}()
+
+		switch typeName {
+
+		default:
+			return errors.New("unknown type: " + typeName)
+		}
+	}
+
+	resolveEntityGroup := func(typeName string, reps []map[string]interface{}, idx []int) {
+		if isMulti(typeName) {
+			err := resolveManyEntities(ctx, typeName, reps, idx)
+			if err != nil {
+				ec.Error(ctx, err)
+			}
+		} else {
+			// if there are multiple entities to resolve, parallelize (similar to
+			// graphql.FieldSet.Dispatch)
+			var e sync.WaitGroup
+			e.Add(len(reps))
+			for i, rep := range reps {
+				i, rep := i, rep
+				go func(i int, rep map[string]interface{}) {
+					err := resolveEntity(ctx, typeName, rep, idx, i)
+					if err != nil {
+						ec.Error(ctx, err)
+					}
+					e.Done()
+				}(i, rep)
+			}
+			e.Wait()
+		}
+	}
+	buildRepresentationGroups(representations)
+
+	switch len(repsMap) {
+	case 0:
+		return list
+	case 1:
+		for typeName, reps := range repsMap {
+			resolveEntityGroup(typeName, reps.r, reps.i)
+		}
+		return list
+	default:
+		var g sync.WaitGroup
+		g.Add(len(repsMap))
+		for typeName, reps := range repsMap {
+			go func(typeName string, reps []map[string]interface{}, idx []int) {
+				resolveEntityGroup(typeName, reps, idx)
+				g.Done()
+			}(typeName, reps.r, reps.i)
+		}
+		g.Wait()
+		return list
+	}
+}
+
+func entityResolverNameForPet(ctx context.Context, rep map[string]interface{}) (string, error) {
+	for {
+		var (
+			m   map[string]interface{}
+			val interface{}
+			ok  bool
+		)
+		_ = val
+		m = rep
+		if _, ok = m["id"]; !ok {
+			break
+		}
+		return "findPetByID", nil
+	}
+	return "", fmt.Errorf("%w for Pet", ErrTypeNotFound)
+}
+
+func entityResolverNameForUser(ctx context.Context, rep map[string]interface{}) (string, error) {
+	for {
+		var (
+			m   map[string]interface{}
+			val interface{}
+			ok  bool
+		)
+		_ = val
+		m = rep
+		if _, ok = m["id"]; !ok {
+			break
+		}
+		return "findUserByID", nil
+	}
+	return "", fmt.Errorf("%w for User", ErrTypeNotFound)
+}

pets/graph/model/models_gen.go

@@ -0,0 +1,17 @@
+// Code generated by github.com/99designs/gqlgen, DO NOT EDIT.
+
+package model
+
+type Pet struct {
+	ID   string `json:"id"`
+	Name string `json:"name"`
+}
+
+func (Pet) IsEntity() {}
+
+type User struct {
+	ID   string `json:"id"`
+	Pets []*Pet `json:"pets"`
+}
+
+func (User) IsEntity() {}

pets/graph/resolver.go

@@ -0,0 +1,8 @@
+//go:generate go run github.com/99designs/gqlgen generate
+package graph
+
+// This file will not be regenerated automatically.
+//
+// It serves as dependency injection for your app, add any dependencies you require here.
+
+type Resolver struct{}

pets/graph/schema.graphqls

@@ -0,0 +1,13 @@
+type Pet @key(fields: "id") {
+  id: ID!
+  name: String!
+}
+
+extend type User @key(fields: "id") {
+  id: ID!
+  pets: [Pet!]!
+}
+
+type Query {
+  pet(id: ID!): Pet
+}

pets/graph/schema.resolvers.go

@@ -0,0 +1,21 @@
+package graph
+
+// This file will be automatically regenerated based on the schema, any resolver implementations
+// will be copied through when generating and any unknown code will be moved to the end.
+// Code generated by github.com/99designs/gqlgen version v0.17.39
+
+import (
+	"context"
+
+	"github.com/Dan6erbond/sitling/pets/graph/model"
+)
+
+// Pet is the resolver for the pet field.
+func (r *queryResolver) Pet(ctx context.Context, id string) (*model.Pet, error) {
+	return &model.Pet{ID: id, Name: "Ace"}, nil
+}
+
+// Query returns QueryResolver implementation.
+func (r *Resolver) Query() QueryResolver { return &queryResolver{r} }
+
+type queryResolver struct{ *Resolver }

pets/server.go

@@ -0,0 +1,28 @@
+package main
+
+import (
+	"log"
+	"net/http"
+	"os"
+
+	"github.com/99designs/gqlgen/graphql/handler"
+	"github.com/99designs/gqlgen/graphql/playground"
+	"github.com/Dan6erbond/sitling/pets/graph"
+)
+
+const defaultPort = "3005"
+
+func main() {
+	port := os.Getenv("PORT")
+	if port == "" {
+		port = defaultPort
+	}
+
+	srv := handler.NewDefaultServer(graph.NewExecutableSchema(graph.Config{Resolvers: &graph.Resolver{}}))
+
+	http.Handle("/", playground.Handler("GraphQL playground", "/query"))
+	http.Handle("/query", srv)
+
+	log.Printf("connect to http://localhost:%s/ for GraphQL playground", port)
+	log.Fatal(http.ListenAndServe(":"+port, nil))
+}

pets/tools.go

@@ -0,0 +1,9 @@
+//go:build tools
+// +build tools
+
+package tools
+
+import (
+	_ "github.com/99designs/gqlgen"
+	_ "github.com/99designs/gqlgen/graphql/introspection"
+)

users/.gitignore

@@ -0,0 +1,21 @@
+# If you prefer the allow list template instead of the deny list, see community template:
+# https://github.com/github/gitignore/blob/main/community/Golang/Go.AllowList.gitignore
+#
+# Binaries for programs and plugins
+*.exe
+*.exe~
+*.dll
+*.so
+*.dylib
+
+# Test binary, built with `go test -c`
+*.test
+
+# Output of the go coverage tool, specifically when used with LiteIDE
+*.out
+
+# Dependency directories (remove the comment below to include it)
+# vendor/
+
+# Go workspace file
+go.work

users/go.mod

@@ -0,0 +1,26 @@
+module github.com/Dan6erbond/sitling/users
+
+go 1.20
+
+require (
+	github.com/99designs/gqlgen v0.17.39
+	github.com/vektah/gqlparser/v2 v2.5.10
+)
+
+require (
+	github.com/agnivade/levenshtein v1.1.1 // indirect
+	github.com/cpuguy83/go-md2man/v2 v2.0.2 // indirect
+	github.com/google/uuid v1.3.0 // indirect
+	github.com/gorilla/websocket v1.5.0 // indirect
+	github.com/hashicorp/golang-lru/v2 v2.0.3 // indirect
+	github.com/mitchellh/mapstructure v1.5.0 // indirect
+	github.com/russross/blackfriday/v2 v2.1.0 // indirect
+	github.com/sosodev/duration v1.1.0 // indirect
+	github.com/urfave/cli/v2 v2.25.5 // indirect
+	github.com/xrash/smetrics v0.0.0-20201216005158-039620a65673 // indirect
+	golang.org/x/mod v0.10.0 // indirect
+	golang.org/x/sys v0.8.0 // indirect
+	golang.org/x/text v0.9.0 // indirect
+	golang.org/x/tools v0.9.3 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)

users/go.sum

@@ -0,0 +1,47 @@
+github.com/99designs/gqlgen v0.17.39 h1:wPTAyc2fqVjAWT5DsJ21k/lLudgnXzURwbsjVNegFpU=
+github.com/99designs/gqlgen v0.17.39/go.mod h1:b62q1USk82GYIVjC60h02YguAZLqYZtvWml8KkhJps4=
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+github.com/agnivade/levenshtein v1.1.1/go.mod h1:veldBMzWxcCG2ZvUTKD2kJNRdCk5hVbJomOvKkmgYbo=
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+github.com/arbovm/levenshtein v0.0.0-20160628152529-48b4e1c0c4d0 h1:jfIu9sQUG6Ig+0+Ap1h4unLjW6YQJpKZVmUzxsD4E/Q=
+github.com/arbovm/levenshtein v0.0.0-20160628152529-48b4e1c0c4d0/go.mod h1:t2tdKJDJF9BV14lnkjHmOQgcvEKgtqs5a1N3LNdJhGE=
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+github.com/cpuguy83/go-md2man/v2 v2.0.2/go.mod h1:tgQtvFlXSQOSOSIRvRPT7W67SCa46tRHOmNcaadrF8o=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/dgryski/trifles v0.0.0-20200323201526-dd97f9abfb48 h1:fRzb/w+pyskVMQ+UbP35JkH8yB7MYb4q/qhBarqZE6g=
+github.com/dgryski/trifles v0.0.0-20200323201526-dd97f9abfb48/go.mod h1:if7Fbed8SFyPtHLHbg49SI7NAdJiC5WIA09pe59rfAA=
+github.com/google/uuid v1.3.0 h1:t6JiXgmwXMjEs8VusXIJk2BXHsn+wx8BZdTaoZ5fu7I=
+github.com/google/uuid v1.3.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/gorilla/websocket v1.5.0 h1:PPwGk2jz7EePpoHN/+ClbZu8SPxiqlu12wZP/3sWmnc=
+github.com/gorilla/websocket v1.5.0/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
+github.com/hashicorp/golang-lru/v2 v2.0.3 h1:kmRrRLlInXvng0SmLxmQpQkpbYAvcXm7NPDrgxJa9mE=
+github.com/hashicorp/golang-lru/v2 v2.0.3/go.mod h1:QeFd9opnmA6QUJc5vARoKUSoFhyfM2/ZepoAG6RGpeM=
+github.com/mitchellh/mapstructure v1.5.0 h1:jeMsZIYE/09sWLaz43PL7Gy6RuMjD2eJVyuac5Z2hdY=
+github.com/mitchellh/mapstructure v1.5.0/go.mod h1:bFUtVrKA4DC2yAKiSyO/QUcy7e+RRV2QTWOzhPopBRo=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/russross/blackfriday/v2 v2.1.0 h1:JIOH55/0cWyOuilr9/qlrm0BSXldqnqwMsf35Ld67mk=
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+github.com/sergi/go-diff v1.3.1 h1:xkr+Oxo4BOQKmkn/B9eMK0g5Kg/983T9DqqPHwYqD+8=
+github.com/sosodev/duration v1.1.0 h1:kQcaiGbJaIsRqgQy7VGlZrVw1giWO+lDoX3MCPnpVO4=
+github.com/sosodev/duration v1.1.0/go.mod h1:RQIBBX0+fMLc/D9+Jb/fwvVmo0eZvDDEERAikUR6SDg=
+github.com/stretchr/testify v1.8.2 h1:+h33VjcLVPDHtOdpUCuF+7gSuG3yGIftsP1YvFihtJ8=
+github.com/urfave/cli/v2 v2.25.5 h1:d0NIAyhh5shGscroL7ek/Ya9QYQE0KNabJgiUinIQkc=
+github.com/urfave/cli/v2 v2.25.5/go.mod h1:GHupkWPMM0M/sj1a2b4wUrWBPzazNrIjouW6fmdJLxc=
+github.com/vektah/gqlparser/v2 v2.5.10 h1:6zSM4azXC9u4Nxy5YmdmGu4uKamfwsdKTwp5zsEealU=
+github.com/vektah/gqlparser/v2 v2.5.10/go.mod h1:1rCcfwB2ekJofmluGWXMSEnPMZgbxzwj6FaZ/4OT8Cc=
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+golang.org/x/mod v0.10.0 h1:lFO9qtOdlre5W1jxS3r/4szv2/6iXxScdzjoBMXNhYk=
+golang.org/x/mod v0.10.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
+golang.org/x/sync v0.2.0 h1:PUR+T4wwASmuSTYdKjYHI5TD22Wy5ogLU5qZCOLxBrI=
+golang.org/x/sys v0.8.0 h1:EBmGv8NaZBZTWvrbjNoL6HVt+IVy3QDQpJs7VRIw3tU=
+golang.org/x/sys v0.8.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/text v0.9.0 h1:2sjJmO8cDvYveuX97RDLsxlyUxLl+GHoLxBiRdHllBE=
+golang.org/x/text v0.9.0/go.mod h1:e1OnstbJyHTd6l/uOt8jFFHp6TRDWZR/bV3emEE/zU8=
+golang.org/x/tools v0.9.3 h1:Gn1I8+64MsuTb/HpH+LmQtNas23LhUVr3rYZ0eKuaMM=
+golang.org/x/tools v0.9.3/go.mod h1:owI94Op576fPu3cIGQeHs3joujW/2Oc6MtlxbF5dfNc=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v2 v2.4.0 h1:D8xgwECY7CYvx+Y2n4sBz93Jn9JRvxdiyyo8CTfuKaY=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

users/gqlgen.yml

@@ -0,0 +1,88 @@
+# Where are all the schema files located? globs are supported eg  src/**/*.graphqls
+schema:
+  - graph/*.graphqls
+
+# Where should the generated server code go?
+exec:
+  filename: graph/generated.go
+  package: graph
+
+# Uncomment to enable federation
+federation:
+  filename: graph/federation.go
+  package: graph
+  version: 2
+
+# Where should any generated models go?
+model:
+  filename: graph/model/models_gen.go
+  package: model
+
+# Where should the resolver implementations go?
+resolver:
+  layout: follow-schema
+  dir: graph
+  package: graph
+  filename_template: "{name}.resolvers.go"
+  # Optional: turn on to not generate template comments above resolvers
+  # omit_template_comment: false
+
+# Optional: turn on use ` + "`" + `gqlgen:"fieldName"` + "`" + ` tags in your models
+# struct_tag: json
+
+# Optional: turn on to use []Thing instead of []*Thing
+# omit_slice_element_pointers: false
+
+# Optional: turn on to omit Is<Name>() methods to interface and unions
+# omit_interface_checks : true
+
+# Optional: turn on to skip generation of ComplexityRoot struct content and Complexity function
+# omit_complexity: false
+
+# Optional: turn on to not generate any file notice comments in generated files
+# omit_gqlgen_file_notice: false
+
+# Optional: turn on to exclude the gqlgen version in the generated file notice. No effect if `omit_gqlgen_file_notice` is true.
+# omit_gqlgen_version_in_file_notice: false
+
+# Optional: turn off to make struct-type struct fields not use pointers
+# e.g. type Thing struct { FieldA OtherThing } instead of { FieldA *OtherThing }
+# struct_fields_always_pointers: true
+
+# Optional: turn off to make resolvers return values instead of pointers for structs
+# resolvers_always_return_pointers: true
+
+# Optional: turn on to return pointers instead of values in unmarshalInput
+# return_pointers_in_unmarshalinput: false
+
+# Optional: wrap nullable input fields with Omittable
+# nullable_input_omittable: true
+
+# Optional: set to speed up generation time by not performing a final validation pass.
+# skip_validation: true
+
+# Optional: set to skip running `go mod tidy` when generating server code
+# skip_mod_tidy: true
+
+# gqlgen will search for any type names in the schema in these go packages
+# if they match it will use them, otherwise it will generate them.
+autobind:
+#  - "github.com/Dan6erbond/sitling/users/users/graph/model"
+
+# This section declares type mapping between the GraphQL and go type systems
+#
+# The first line in each type will be used as defaults for resolver arguments and
+# modelgen, the others will be allowed when binding to fields. Configure them to
+# your liking
+models:
+  ID:
+    model:
+      - github.com/99designs/gqlgen/graphql.ID
+      - github.com/99designs/gqlgen/graphql.Int
+      - github.com/99designs/gqlgen/graphql.Int64
+      - github.com/99designs/gqlgen/graphql.Int32
+  Int:
+    model:
+      - github.com/99designs/gqlgen/graphql.Int
+      - github.com/99designs/gqlgen/graphql.Int64
+      - github.com/99designs/gqlgen/graphql.Int32

users/graph/entity.resolvers.go

@@ -0,0 +1,26 @@
+package graph
+
+// This file will be automatically regenerated based on the schema, any resolver implementations
+// will be copied through when generating and any unknown code will be moved to the end.
+// Code generated by github.com/99designs/gqlgen version v0.17.39
+
+import (
+	"context"
+
+	"github.com/Dan6erbond/sitling/users/graph/model"
+)
+
+// FindPetByID is the resolver for the findPetByID field.
+func (r *entityResolver) FindPetByID(ctx context.Context, id string) (*model.Pet, error) {
+	return &model.Pet{ID: id}, nil
+}
+
+// FindUserByID is the resolver for the findUserByID field.
+func (r *entityResolver) FindUserByID(ctx context.Context, id string) (*model.User, error) {
+	return &model.User{ID: id}, nil
+}
+
+// Entity returns EntityResolver implementation.
+func (r *Resolver) Entity() EntityResolver { return &entityResolver{r} }
+
+type entityResolver struct{ *Resolver }

users/graph/federation.go

@@ -0,0 +1,224 @@
+// Code generated by github.com/99designs/gqlgen, DO NOT EDIT.
+
+package graph
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"strings"
+	"sync"
+
+	"github.com/99designs/gqlgen/plugin/federation/fedruntime"
+)
+
+var (
+	ErrUnknownType  = errors.New("unknown type")
+	ErrTypeNotFound = errors.New("type not found")
+)
+
+func (ec *executionContext) __resolve__service(ctx context.Context) (fedruntime.Service, error) {
+	if ec.DisableIntrospection {
+		return fedruntime.Service{}, errors.New("federated introspection disabled")
+	}
+
+	var sdl []string
+
+	for _, src := range sources {
+		if src.BuiltIn {
+			continue
+		}
+		sdl = append(sdl, src.Input)
+	}
+
+	return fedruntime.Service{
+		SDL: strings.Join(sdl, "\n"),
+	}, nil
+}
+
+func (ec *executionContext) __resolve_entities(ctx context.Context, representations []map[string]interface{}) []fedruntime.Entity {
+	list := make([]fedruntime.Entity, len(representations))
+
+	repsMap := map[string]struct {
+		i []int
+		r []map[string]interface{}
+	}{}
+
+	// We group entities by typename so that we can parallelize their resolution.
+	// This is particularly helpful when there are entity groups in multi mode.
+	buildRepresentationGroups := func(reps []map[string]interface{}) {
+		for i, rep := range reps {
+			typeName, ok := rep["__typename"].(string)
+			if !ok {
+				// If there is no __typename, we just skip the representation;
+				// we just won't be resolving these unknown types.
+				ec.Error(ctx, errors.New("__typename must be an existing string"))
+				continue
+			}
+
+			_r := repsMap[typeName]
+			_r.i = append(_r.i, i)
+			_r.r = append(_r.r, rep)
+			repsMap[typeName] = _r
+		}
+	}
+
+	isMulti := func(typeName string) bool {
+		switch typeName {
+		default:
+			return false
+		}
+	}
+
+	resolveEntity := func(ctx context.Context, typeName string, rep map[string]interface{}, idx []int, i int) (err error) {
+		// we need to do our own panic handling, because we may be called in a
+		// goroutine, where the usual panic handling can't catch us
+		defer func() {
+			if r := recover(); r != nil {
+				err = ec.Recover(ctx, r)
+			}
+		}()
+
+		switch typeName {
+		case "Pet":
+			resolverName, err := entityResolverNameForPet(ctx, rep)
+			if err != nil {
+				return fmt.Errorf(`finding resolver for Entity "Pet": %w`, err)
+			}
+			switch resolverName {
+
+			case "findPetByID":
+				id0, err := ec.unmarshalNID2string(ctx, rep["id"])
+				if err != nil {
+					return fmt.Errorf(`unmarshalling param 0 for findPetByID(): %w`, err)
+				}
+				entity, err := ec.resolvers.Entity().FindPetByID(ctx, id0)
+				if err != nil {
+					return fmt.Errorf(`resolving Entity "Pet": %w`, err)
+				}
+
+				list[idx[i]] = entity
+				return nil
+			}
+		case "User":
+			resolverName, err := entityResolverNameForUser(ctx, rep)
+			if err != nil {
+				return fmt.Errorf(`finding resolver for Entity "User": %w`, err)
+			}
+			switch resolverName {
+
+			case "findUserByID":
+				id0, err := ec.unmarshalNID2string(ctx, rep["id"])
+				if err != nil {
+					return fmt.Errorf(`unmarshalling param 0 for findUserByID(): %w`, err)
+				}
+				entity, err := ec.resolvers.Entity().FindUserByID(ctx, id0)
+				if err != nil {
+					return fmt.Errorf(`resolving Entity "User": %w`, err)
+				}
+
+				list[idx[i]] = entity
+				return nil
+			}
+
+		}
+		return fmt.Errorf("%w: %s", ErrUnknownType, typeName)
+	}
+
+	resolveManyEntities := func(ctx context.Context, typeName string, reps []map[string]interface{}, idx []int) (err error) {
+		// we need to do our own panic handling, because we may be called in a
+		// goroutine, where the usual panic handling can't catch us
+		defer func() {
+			if r := recover(); r != nil {
+				err = ec.Recover(ctx, r)
+			}
+		}()
+
+		switch typeName {
+
+		default:
+			return errors.New("unknown type: " + typeName)
+		}
+	}
+
+	resolveEntityGroup := func(typeName string, reps []map[string]interface{}, idx []int) {
+		if isMulti(typeName) {
+			err := resolveManyEntities(ctx, typeName, reps, idx)
+			if err != nil {
+				ec.Error(ctx, err)
+			}
+		} else {
+			// if there are multiple entities to resolve, parallelize (similar to
+			// graphql.FieldSet.Dispatch)
+			var e sync.WaitGroup
+			e.Add(len(reps))
+			for i, rep := range reps {
+				i, rep := i, rep
+				go func(i int, rep map[string]interface{}) {
+					err := resolveEntity(ctx, typeName, rep, idx, i)
+					if err != nil {
+						ec.Error(ctx, err)
+					}
+					e.Done()
+				}(i, rep)
+			}
+			e.Wait()
+		}
+	}
+	buildRepresentationGroups(representations)
+
+	switch len(repsMap) {
+	case 0:
+		return list
+	case 1:
+		for typeName, reps := range repsMap {
+			resolveEntityGroup(typeName, reps.r, reps.i)
+		}
+		return list
+	default:
+		var g sync.WaitGroup
+		g.Add(len(repsMap))
+		for typeName, reps := range repsMap {
+			go func(typeName string, reps []map[string]interface{}, idx []int) {
+				resolveEntityGroup(typeName, reps, idx)
+				g.Done()
+			}(typeName, reps.r, reps.i)
+		}
+		g.Wait()
+		return list
+	}
+}
+
+func entityResolverNameForPet(ctx context.Context, rep map[string]interface{}) (string, error) {
+	for {
+		var (
+			m   map[string]interface{}
+			val interface{}
+			ok  bool
+		)
+		_ = val
+		m = rep
+		if _, ok = m["id"]; !ok {
+			break
+		}
+		return "findPetByID", nil
+	}
+	return "", fmt.Errorf("%w for Pet", ErrTypeNotFound)
+}
+
+func entityResolverNameForUser(ctx context.Context, rep map[string]interface{}) (string, error) {
+	for {
+		var (
+			m   map[string]interface{}
+			val interface{}
+			ok  bool
+		)
+		_ = val
+		m = rep
+		if _, ok = m["id"]; !ok {
+			break
+		}
+		return "findUserByID", nil
+	}
+	return "", fmt.Errorf("%w for User", ErrTypeNotFound)
+}

users/graph/model/models_gen.go

@@ -0,0 +1,16 @@
+// Code generated by github.com/99designs/gqlgen, DO NOT EDIT.
+
+package model
+
+type Pet struct {
+	ID     string  `json:"id"`
+	Owners []*User `json:"owners"`
+}
+
+func (Pet) IsEntity() {}
+
+type User struct {
+	ID string `json:"id"`
+}
+
+func (User) IsEntity() {}

users/graph/resolver.go

@@ -0,0 +1,8 @@
+//go:generate go run github.com/99designs/gqlgen generate
+package graph
+
+// This file will not be regenerated automatically.
+//
+// It serves as dependency injection for your app, add any dependencies you require here.
+
+type Resolver struct{}

users/graph/schema.graphqls

@@ -0,0 +1,8 @@
+type User @key(fields: "id") {
+  id: ID!
+}
+
+extend type Pet @key(fields: "id") {
+  id: ID!
+  owners: [User!]!
+}

users/server.go

@@ -0,0 +1,28 @@
+package main
+
+import (
+	"log"
+	"net/http"
+	"os"
+
+	"github.com/99designs/gqlgen/graphql/handler"
+	"github.com/99designs/gqlgen/graphql/playground"
+	"github.com/Dan6erbond/sitling/users/graph"
+)
+
+const defaultPort = "3006"
+
+func main() {
+	port := os.Getenv("PORT")
+	if port == "" {
+		port = defaultPort
+	}
+
+	srv := handler.NewDefaultServer(graph.NewExecutableSchema(graph.Config{Resolvers: &graph.Resolver{}}))
+
+	http.Handle("/", playground.Handler("GraphQL playground", "/query"))
+	http.Handle("/query", srv)
+
+	log.Printf("connect to http://localhost:%s/ for GraphQL playground", port)
+	log.Fatal(http.ListenAndServe(":"+port, nil))
+}

users/tools.go

@@ -0,0 +1,9 @@
+//go:build tools
+// +build tools
+
+package tools
+
+import (
+	_ "github.com/99designs/gqlgen"
+	_ "github.com/99designs/gqlgen/graphql/introspection"
+)