From 5042a9a549dd4d8ad3f0d2a7e2eb2c5a6e88bdf4 Mon Sep 17 00:00:00 2001
From: Ben Kraft <benkraft@khanacademy.org>
Date: Fri, 1 May 2020 18:45:31 -0700
Subject: [PATCH] allow omitting context

---
 README.md                  |  6 +++---
 example/genql.yaml         |  3 ++-
 generate/config.go         | 26 +++++++++-----------------
 generate/generate.go       | 14 +++++++-------
 generate/operation.go.tmpl |  6 +++---
 5 files changed, 24 insertions(+), 31 deletions(-)

diff --git a/README.md b/README.md
index 807472c..2d9a551 100644
--- a/README.md
+++ b/README.md
@@ -53,6 +53,8 @@ For a complete working example, see `example/`.
 
 `go test ./...` does some perfunctory tests.  (This is run by GitHub Actions.)
 
+`make example` tests that everything wires up to a real API correctly.
+
 TODO(benkraft): Figure out how to get GitHub Actions to run the example -- it needs a token.
 
 ## Major TODOs
@@ -62,9 +64,7 @@ Query structures to support:
 - fragments
 
 Config options:
-- file locations (queries, generated, schema (or get via HTTP))
-- use ctx or not, including complexities of how Khan uses context
-- HTTP calling convention (is there enough variation to matter?)
+- get schema via HTTP (perhaps even via GraphQL introspection)
 - proper config/arguments setup (e.g. with [viper](https://github.com/spf13/viper)
 
 Other:
diff --git a/example/genql.yaml b/example/genql.yaml
index e6def54..8792985 100644
--- a/example/genql.yaml
+++ b/example/genql.yaml
@@ -1,5 +1,6 @@
-# These are the defaults.
+# These are the defaults, and are just included to be explicit.
 package: example
 schema: schema.graphql
 queries: queries.graphql
 generated: generated.go
+use_context: true
diff --git a/generate/config.go b/generate/config.go
index abd4a1c..41f7591 100644
--- a/generate/config.go
+++ b/generate/config.go
@@ -9,9 +9,10 @@ import (
 )
 
 var defaultConfig = &Config{
-	Schema:    "schema.graphql",
-	Queries:   "queries.graphql",
-	Generated: "generated.go",
+	Schema:     "schema.graphql",
+	Queries:    "queries.graphql",
+	Generated:  "generated.go",
+	UseContext: true,
 }
 
 type Config struct {
@@ -28,19 +29,12 @@ type Config struct {
 	// The filename to which to write the generated code; defaults to
 	// generated.go
 	Generated string `yaml:"generated"`
+	// Whether the generated helpers should accept a context.Context which will
+	// be used to make the request; defaults to true.
+	UseContext bool `yaml:"use_context"`
 }
 
 func (c *Config) ValidateAndFillDefaults() error {
-	if c.Schema == "" {
-		c.Schema = defaultConfig.Schema
-	}
-	if c.Queries == "" {
-		c.Queries = defaultConfig.Queries
-	}
-	if c.Generated == "" {
-		c.Generated = defaultConfig.Generated
-	}
-
 	if c.Package == "" {
 		abs, err := filepath.Abs(c.Generated)
 		if err != nil {
@@ -56,10 +50,8 @@ func (c *Config) ValidateAndFillDefaults() error {
 }
 
 func ReadAndValidateConfig(filename string) (*Config, error) {
-	var config Config
-	if filename == "" {
-		config = *defaultConfig
-	} else {
+	config := *defaultConfig
+	if filename != "" {
 		text, err := ioutil.ReadFile(filename)
 		if err != nil {
 			return nil, fmt.Errorf("unreadable config file %v: %v", filename, err)
diff --git a/generate/generate.go b/generate/generate.go
index 3bba20c..1784779 100644
--- a/generate/generate.go
+++ b/generate/generate.go
@@ -24,8 +24,8 @@ var tmpl = template.Must(template.ParseFiles(tmplAbsFilename))
 // generator is the context for the codegen process (and ends up getting passed
 // to the template).
 type generator struct {
-	// The name of the package into which to generate the operation-helpers.
-	PackageName string
+	// The config for which we are generating code.
+	Config *Config
 	// The list of operations for which to generate code.
 	Operations []operation
 	// The types needed for these operations.
@@ -54,11 +54,11 @@ type argument struct {
 	GraphQLName string
 }
 
-func newGenerator(packageName string, schema *ast.Schema) *generator {
+func newGenerator(config *Config, schema *ast.Schema) *generator {
 	return &generator{
-		PackageName: packageName,
-		typeMap:     map[string]string{},
-		schema:      schema,
+		Config:  config,
+		typeMap: map[string]string{},
+		schema:  schema,
 	}
 }
 
@@ -157,7 +157,7 @@ func Generate(config *Config) ([]byte, error) {
 		return nil, err
 	}
 
-	g := newGenerator(config.Package, schema)
+	g := newGenerator(config, schema)
 	for _, op := range document.Operations {
 		if err = g.addOperation(op); err != nil {
 			return nil, err
diff --git a/generate/operation.go.tmpl b/generate/operation.go.tmpl
index 28e7b34..0b3734a 100644
--- a/generate/operation.go.tmpl
+++ b/generate/operation.go.tmpl
@@ -1,4 +1,4 @@
-package {{.PackageName}}
+package {{$.Config.Package}}
 
 // Code generated by github.com/Khan/genql, DO NOT EDIT.
 
@@ -12,7 +12,7 @@ import (
 
 {{range .Operations}}
 {{.Doc}}
-func {{.Name}}(ctx context.Context, client *graphql.Client{{range .Args}}, {{.GoName}} {{.GoType}}{{end}}) (*{{.ResponseName}}, error) {
+func {{.Name}}({{if $.Config.UseContext}}ctx context.Context, {{end}}client *graphql.Client{{range .Args}}, {{.GoName}} {{.GoType}}{{end}}) (*{{.ResponseName}}, error) {
     {{- if .Args -}}
     variables := map[string]interface{}{
         {{range .Args -}}
@@ -21,7 +21,7 @@ func {{.Name}}(ctx context.Context, client *graphql.Client{{range .Args}}, {{.Go
     }
     {{end}}
 	var retval {{.ResponseName}}
-    err := client.MakeRequest(ctx, `{{.Body}}`, &retval, {{if .Args}}variables{{else}}nil{{end}})
+    err := client.MakeRequest({{if $.Config.UseContext}}ctx{{else}}context.Background(){{end}}, `{{.Body}}`, &retval, {{if .Args}}variables{{else}}nil{{end}})
     return &retval, err
 }
 {{end}}