move a bunch of the logic from generated into client

example/caller.go

@@ -4,10 +4,13 @@ import (
 	"context"
 	"fmt"
 	"os"
+
+	"github.com/Khan/genql/graphql"
 )
 
 func Main() {
-	resp, err := getViewer(context.Background())
+	client := graphql.NewClient("https://api.github.com/graphql", nil)
+	resp, err := getViewer(context.Background(), client)
 	if err != nil {
 		fmt.Println(err)
 		os.Exit(1)

example/generated.go

@@ -2,13 +2,8 @@ package example
 
 import (
 	"context"
-	"encoding/json"
-	"fmt"
-	"io/ioutil"
-	"net/http"
-	"strings"
 
-	"github.com/vektah/gqlparser/gqlerror"
+	"github.com/Khan/genql/graphql"
 )
 
 type getViewerResponse = struct {
@@ -18,49 +13,14 @@ type getViewerResponse = struct {
 }
 
 // TODO
-func getViewer(ctx context.Context) (*getViewerResponse, error) {
-	req, err := http.NewRequest(
-		http.MethodPost,
-		`https://api.github.com/graphql`,
-		strings.NewReader(`
+func getViewer(ctx context.Context, client *graphql.Client) (*getViewerResponse, error) {
+	var retval getViewerResponse
+	err := client.MakeRequest(ctx, `
 query getViewer {
 	Viewer: viewer {
 		Name: name
 	}
 }
-`))
-	if err != nil {
-		return nil, err
-	}
-
-	req = req.WithContext(ctx)
-	resp, err := http.DefaultClient.Do(req)
-	if err != nil {
-		return nil, err
-	}
-	defer resp.Body.Close()
-
-	body, err := ioutil.ReadAll(resp.Body)
-	if err != nil {
-		return nil, err
-	}
-
-	if resp.StatusCode != http.StatusOK {
-		return nil, fmt.Errorf("returned error %v: %v", resp.Status, string(body))
-	}
-
-	var retval struct {
-		Data   getViewerResponse `json:"data"`
-		Errors gqlerror.List     `json:"errors"`
-	}
-	err = json.Unmarshal(body, &retval)
-	if err != nil {
-		return nil, err
-	}
-
-	if len(retval.Errors) > 0 {
-		return nil, retval.Errors
-	}
-
-	return &retval.Data, nil
+`, &retval)
+	return &retval, err
 }

generate/generate.go

@@ -40,8 +40,6 @@ type OperationParams struct {
 	OperationName string
 	// The documentation for the operation, from GraphQL.
 	OperationDoc string
-	// The endpoint to which to send queries.
-	Endpoint string
 	// The body of the operation to send.
 	Operation string
 }
@@ -89,16 +87,15 @@ func Generate(specFilename, schemaFilename, generatedFilename string) error {
 	if generatedFilename == "-" {
 		out = os.Stdout
 	} else {
-		out, err = os.OpenFile(generatedFilename, os.O_RDWR|os.O_CREATE, 0755)
+		out, err = os.OpenFile(generatedFilename, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0755)
 		if err != nil {
 			return fmt.Errorf("could not open generated file %v: %v",
 				generatedFilename, err)
 		}
 	}
 
-	// TODO: configure these
+	// TODO: configure this
 	packageName := "example"
-	endpoint := "https://api.github.com/graphql"
 
 	// TODO: this should probably get factored out
 	operations := make([]OperationParams, len(document.Operations))
@@ -125,7 +122,6 @@ func Generate(specFilename, schemaFilename, generatedFilename string) error {
 			ResponseName: operation.Name + "Response",
 			ResponseType: typeFor(operation, schema),
 
-			Endpoint: endpoint,
 			// The newline just makes it format a little nicer
 			Operation: "\n" + builder.String(),
 		}

generate/operation.go.tmpl

@@ -2,57 +2,17 @@ package {{.PackageName}}
 
 import (
 	"context"
-	"encoding/json"
-	"fmt"
-	"io/ioutil"
-	"net/http"
-	"strings"
 
-	"github.com/vektah/gqlparser/gqlerror"
+    "github.com/Khan/genql/graphql"
 )
 
 {{range .Operations}}
 type {{.ResponseName}} = {{.ResponseType}}
 
 // {{.OperationDoc}}
-func {{.OperationName}}(ctx context.Context) (*{{.ResponseName}}, error) {
-	req, err := http.NewRequest(
-		http.MethodPost,
-		`{{.Endpoint}}`,
-		strings.NewReader(`{{.Operation}}`))
-	if err != nil {
-		return nil, err
-	}
-
-	req = req.WithContext(ctx)
-	resp, err := http.DefaultClient.Do(req)
-	if err != nil {
-		return nil, err
-	}
-	defer resp.Body.Close()
-
-	body, err := ioutil.ReadAll(resp.Body)
-	if err != nil {
-		return nil, err
-	}
-
-	if resp.StatusCode != http.StatusOK {
-		return nil, fmt.Errorf("returned error %v: %v", resp.Status, string(body))
-	}
-
-	var retval struct {
-		Data   {{.ResponseName}} `json:"data"`
-		Errors gqlerror.List     `json:"errors"`
-	}
-	err = json.Unmarshal(body, &retval)
-	if err != nil {
-		return nil, err
-	}
-
-	if len(retval.Errors) > 0 {
-		return nil, retval.Errors
-	}
-
-	return &retval.Data, nil
+func {{.OperationName}}(ctx context.Context, client *graphql.Client) (*{{.ResponseName}}, error) {
+	var retval {{.ResponseName}}
+    err := client.MakeRequest(ctx, `{{.Operation}}`, &retval)
+    return &retval, err
 }
 {{end}}

go.mod

@@ -2,4 +2,9 @@ module github.com/Khan/genql
 
 go 1.13
 
-require github.com/vektah/gqlparser v1.2.0
+require (
+	github.com/Khan/graphql v0.0.0-20191109005718-3b51154b2bc5
+	github.com/shurcooL/graphql v0.0.0-20181231061246-d48a9a75455f // indirect
+	github.com/vektah/gqlparser v1.2.0
+	golang.org/x/net v0.0.0-20191209160850-c0dbc17a3553 // indirect
+)

go.sum

@@ -1,13 +1,22 @@
+github.com/Khan/graphql v0.0.0-20191109005718-3b51154b2bc5 h1:C7qbo6snTa0/lSpVKYhXiw3dJ/9FYiwZSsU+4Bov9qg=
+github.com/Khan/graphql v0.0.0-20191109005718-3b51154b2bc5/go.mod h1:DLkRTcWV7KR4zw1iTm1lpShI3XP3nFmIMs3fHxYAsF0=
 github.com/agnivade/levenshtein v1.0.1 h1:3oJU7J3FGFmyhn8KHjmVaZCN5hxTr7GxgRue+sxIXdQ=
 github.com/agnivade/levenshtein v1.0.1/go.mod h1:CURSv5d9Uaml+FovSIICkLbAUZ9S4RqaHDIsdSBg7lM=
 github.com/andreyvit/diff v0.0.0-20170406064948-c7f18ee00883/go.mod h1:rCTlJbsFo29Kk6CurOXKm700vrz8f0KW0JNfpkRJY/8=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/sergi/go-diff v1.0.0/go.mod h1:0CfEIISq7TuYL3j771MWULgwwjU+GofnZX9QAmXWZgo=
+github.com/shurcooL/graphql v0.0.0-20181231061246-d48a9a75455f h1:tygelZueB1EtXkPI6mQ4o9DQ0+FKW41hTbunoXZCTqk=
+github.com/shurcooL/graphql v0.0.0-20181231061246-d48a9a75455f/go.mod h1:AuYgA5Kyo4c7HfUmvRGs/6rGlMMV/6B1bVnB9JxJEEg=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
 github.com/vektah/gqlparser v1.2.0 h1:ntkSCX7F5ZJKl+HIVnmLaO269MruasVpNiMOjX9kgo0=
 github.com/vektah/gqlparser v1.2.0/go.mod h1:bkVf0FX+Stjg/MHnm8mEyubuaArhNEqfQhF+OTiAL74=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/net v0.0.0-20191209160850-c0dbc17a3553 h1:efeOvDhwQ29Dj3SdAV/MJf8oukgn+8D8WgaCaRMchF8=
+golang.org/x/net v0.0.0-20191209160850-c0dbc17a3553/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/tools v0.0.0-20190125232054-d66bd3c5d5a6/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=

graphql/client.go

@@ -0,0 +1,67 @@
+package graphql
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"strings"
+
+	"github.com/vektah/gqlparser/gqlerror"
+)
+
+type Client struct {
+	endpoint   string
+	method     string
+	httpClient *http.Client
+}
+
+func NewClient(endpoint string, httpClient *http.Client) *Client {
+	if httpClient == nil {
+		httpClient = http.DefaultClient
+	}
+	return &Client{endpoint, http.MethodPost, httpClient}
+}
+
+func (client *Client) MakeRequest(ctx context.Context, query string, retval interface{}) error {
+	req, err := http.NewRequest(
+		client.method,
+		client.endpoint,
+		strings.NewReader(query))
+	if err != nil {
+		return err
+	}
+
+	req = req.WithContext(ctx)
+	resp, err := client.httpClient.Do(req)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+
+	body, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return err
+	}
+
+	if resp.StatusCode != http.StatusOK {
+		return fmt.Errorf("returned error %v: %v", resp.Status, string(body))
+	}
+
+	var dataAndErrors struct {
+		Data   json.RawMessage `json:"data"`
+		Errors gqlerror.List   `json:"errors"`
+	}
+
+	err = json.Unmarshal(body, &dataAndErrors)
+	if err != nil {
+		return err
+	}
+
+	if len(dataAndErrors.Errors) > 0 {
+		return dataAndErrors.Errors
+	}
+
+	return json.Unmarshal(dataAndErrors.Data, &retval)
+}