allow globbing, and extract queries from .go files

README.md

@@ -51,6 +51,8 @@ fmt.Println("you are", viewerResp.Viewer.MyName)
 
 For a complete working example, see `example/`.
 
+TODO: document this a bit more, including different ways to specify queries, options once we have those, etc.
+
 ## Documentation for generated code
 
 For each GraphQL operation (query or mutation), genqlient generates a Go function with the exact same name, which accepts:
@@ -64,13 +66,11 @@ TODO: document generated types further, especially if they become customizable.
 
 ## Tests
 
-`go test ./...` tests code generation.  (This is run by GitHub Actions.)
+`go test ./...` tests code generation.  (This is run by GitHub Actions.)  Most of the tests are snapshot-based; see `generate/generate_test.go`.
 
-Most of the tests are snapshot-based; they use the schema, queries, and snapshots in `generate/testdata`.  The schema is in `schema.graphql`; the queries are in `TestName.graphql`.  The test by default asserts that the output of the generator matches the snapshot `TestName.graphql.go`.  To update the snapshots, run with `UPDATE_SNAPSHOTS=1`; it will fail the tests and print the diffs, but regenerate the snapshots.  Make sure to check that the output is sensible!
+`make example` rebuilds the example, and tests that everything wires up to a real API correctly.  This is not currently included in `go test`, since it requires a token.
 
-`make example` rebuilds the example, and tests that everything wires up to a real API correctly.
+TODO(benkraft): Figure out how to get GitHub Actions a token to run the example.
-
-TODO(benkraft): Figure out how to get GitHub Actions to run the example -- it needs a token.
 
 ## Design
 
@@ -103,3 +103,4 @@ Other:
 - get a designer to fix my bad logo-thing
 - custom scalar types (or custom mappings for standard scalars, if you want a special ID type say)
 - allow mapping a custom type to a particular val (if you want to use a named type for some string, say)
+- (optionally?) include full query in generated godoc

generate/config.go

@@ -27,6 +27,10 @@ type Config struct {
 	// how to convert that to SDL).
 	Schema string `yaml:"schema"`
 	// Filenames or globs with the queries; defaults to queries.graphql.
+	//
+	// These may be .graphql files, containing the queries in SDL format, or
+	// Go files, in which case any string-literal starting with (optional
+	// whitespace and) the string "# @genqlient" will be extracted as a query.
 	Queries []string `yaml:"queries"`
 	// The filename to which to write the generated code; defaults to
 	// generated.go

generate/generate_test.go

@@ -11,7 +11,7 @@ import (
 	"testing"
 )
 
-const dataDir = "testdata"
+const dataDir = "testdata/queries"
 
 func readFile(t *testing.T, filename string, allowNotExist bool) string {
 	t.Helper()
@@ -34,6 +34,18 @@ func gofmt(src string) (string, error) {
 	return string(formatted), nil
 }
 
+// TestGenerate is a snapshot-based test of code-generation.
+//
+// This file just has the test runner; the actual data is all in
+// testdata/queries.  Specifically, the schema used for all the queries is in
+// schema.graphql; the queries themselves are in TestName.graphql.  The test
+// asserts that running genqlient on that query produces the generated code in
+// the snapshot-file TestName.graphql.go.
+//
+// To update the snapshots (if the code-generator has changed), run the test
+// with `UPDATE_SNAPSHOTS=1`; it will fail the tests and print any diffs, but
+// update the snapshots.  Make sure to check that the output is sensible; the
+// snapshots don't even get compiled!
 func TestGenerate(t *testing.T) {
 	update := (os.Getenv("UPDATE_SNAPSHOTS") == "1")
 
@@ -56,8 +68,8 @@ func TestGenerate(t *testing.T) {
 			}
 
 			goCode, err := Generate(&Config{
-				Schema:  filepath.Join("testdata", "schema.graphql"),
+				Schema:  filepath.Join(dataDir, "schema.graphql"),
-				Queries: []string{filepath.Join("testdata", graphqlFilename)},
+				Queries: []string{filepath.Join(dataDir, graphqlFilename)},
 				Package: "test",
 			})
 			if err != nil {

generate/parse.go

@@ -2,8 +2,14 @@ package generate
 
 import (
 	"fmt"
+	goAst "go/ast"
+	goParser "go/parser"
+	"go/token"
+	goToken "go/token"
 	"io/ioutil"
 	"path/filepath"
+	"strconv"
+	"strings"
 
 	"github.com/vektah/gqlparser/v2"
 	"github.com/vektah/gqlparser/v2/ast"
@@ -28,44 +34,76 @@ func getSchema(filename string) (*ast.Schema, error) {
 }
 
 func getAndValidateQueries(filenames []string, schema *ast.Schema) (*ast.QueryDocument, error) {
+	queryDoc, err := getQueries(filenames)
+	if err != nil {
+		return nil, err
+	}
+
+	// Cf. gqlparser.LoadQuery
+	graphqlErrors := validator.Validate(schema, queryDoc)
+	if graphqlErrors != nil {
+		return nil, fmt.Errorf("query-spec does not match schema: %v", graphqlErrors)
+	}
+
+	return queryDoc, nil
+}
+
+func getQueries(filenames []string) (*ast.QueryDocument, error) {
 	// We merge all the queries into a single query-document, since operations
 	// in one might reference fragments in another.
 	//
 	// TODO(benkraft): It might be better to merge just within a filename, so
 	// that fragment-names don't need to be unique across files.
 	mergedQueryDoc := new(ast.QueryDocument)
+	addQueryDoc := func(queryDoc *ast.QueryDocument) {
+		mergedQueryDoc.Operations = append(mergedQueryDoc.Operations, queryDoc.Operations...)
+		mergedQueryDoc.Fragments = append(mergedQueryDoc.Fragments, queryDoc.Fragments...)
+	}
 
+	expandedFilenames := make([]string, 0, len(filenames))
 	for _, filename := range filenames {
+		matches, err := filepath.Glob(filename)
+		if err != nil {
+			return nil, fmt.Errorf("can't expand file-glob %v: %v", filename, err)
+		}
+		expandedFilenames = append(expandedFilenames, matches...)
+	}
+
+	for _, filename := range expandedFilenames {
+		text, err := ioutil.ReadFile(filename)
+		if err != nil {
+			return nil, fmt.Errorf("unreadable query-spec file %v: %v", filename, err)
+		}
+
 		switch filepath.Ext(filename) {
 		case ".graphql":
-			// Cf. gqlparser.LoadQuery
-			text, err := ioutil.ReadFile(filename)
-			if err != nil {
-				return nil, fmt.Errorf("unreadable query-spec file %v: %v", filename, err)
-			}
-
 			queryDoc, err := getQueriesFromString(string(text), filename)
 			if err != nil {
 				return nil, err
 			}
 
-			mergedQueryDoc.Operations = append(mergedQueryDoc.Operations, queryDoc.Operations...)
+			addQueryDoc(queryDoc)
-			mergedQueryDoc.Fragments = append(mergedQueryDoc.Fragments, queryDoc.Fragments...)
+
+		case ".go":
+			queryDocs, err := getQueriesFromGo(string(text), filename)
+			if err != nil {
+				return nil, err
+			}
+
+			for _, queryDoc := range queryDocs {
+				addQueryDoc(queryDoc)
+			}
 
 		default:
 			return nil, fmt.Errorf("unknown file type: %v", filename)
 		}
 	}
 
-	graphqlErrors := validator.Validate(schema, mergedQueryDoc)
-	if graphqlErrors != nil {
-		return nil, fmt.Errorf("query-spec does not match schema: %v", graphqlErrors)
-	}
-
 	return mergedQueryDoc, nil
 }
 
 func getQueriesFromString(text string, filename string) (*ast.QueryDocument, error) {
+	// Cf. gqlparser.LoadQuery
 	document, graphqlError := parser.ParseQuery(
 		&ast.Source{Name: filename, Input: text})
 	if graphqlError != nil { // ParseQuery returns type *graphql.Error, yuck
@@ -74,3 +112,45 @@ func getQueriesFromString(text string, filename string) (*ast.QueryDocument, err
 
 	return document, nil
 }
+
+func getQueriesFromGo(text string, filename string) ([]*ast.QueryDocument, error) {
+	fset := goToken.NewFileSet()
+	f, err := goParser.ParseFile(fset, filename, text, 0)
+	if err != nil {
+		return nil, fmt.Errorf("invalid Go file %v: %v", filename, err)
+	}
+
+	var retval []*ast.QueryDocument
+	goAst.Inspect(f, func(node goAst.Node) bool {
+		if err != nil {
+			return false // don't bother to recurse if something already failed
+		}
+
+		basicLit, ok := node.(*goAst.BasicLit)
+		if !ok || basicLit.Kind != token.STRING {
+			return true // recurse
+		}
+
+		var value string
+		value, err := strconv.Unquote(basicLit.Value)
+		if err != nil {
+			return false
+		}
+
+		if !strings.HasPrefix(strings.TrimSpace(value), "# @genqlient") {
+			return true
+		}
+
+		fakeFilename := fset.Position(basicLit.Pos()).String()
+		var query *ast.QueryDocument
+		query, err = getQueriesFromString(value, fakeFilename)
+		if err != nil {
+			return false
+		}
+		retval = append(retval, query)
+
+		return true
+	})
+
+	return retval, err
+}

generate/parse_test.go

@@ -0,0 +1,59 @@
+package generate
+
+import (
+	"path/filepath"
+	"sort"
+	"testing"
+
+	"github.com/vektah/gqlparser/v2/ast"
+)
+
+var parseDataDir = "testdata/parsing"
+
+func sortQueries(queryDoc *ast.QueryDocument) {
+	sort.Slice(queryDoc.Operations, func(i, j int) bool {
+		return queryDoc.Operations[i].Name < queryDoc.Operations[j].Name
+	})
+	sort.Slice(queryDoc.Fragments, func(i, j int) bool {
+		return queryDoc.Fragments[i].Name < queryDoc.Fragments[j].Name
+	})
+}
+
+// TestParse tests that query-extraction from different language source files
+// produces equivalent results.  We do not test the results it produces (that's
+// covered by TestGenerate), just that they are equivalent in different
+// languages (since TestGenerate only uses .graphql as input).
+func TestParse(t *testing.T) {
+	extensions := []string{"go"}
+
+	graphqlQueries, err := getQueries([]string{filepath.Join(parseDataDir, "*.graphql")})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// check it's at least non-empty
+	if len(graphqlQueries.Operations) == 0 || len(graphqlQueries.Fragments) == 0 {
+		t.Fatalf("Didn't find any queries in *.graphql files")
+	}
+
+	sortQueries(graphqlQueries)
+
+	for _, ext := range extensions {
+		t.Run(ext, func(t *testing.T) {
+			queries, err := getQueries([]string{filepath.Join(parseDataDir, "*."+ext)})
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			// The different file-types may have the operations/fragments in a
+			// different order.
+			sortQueries(queries)
+
+			got, want := ast.Dump(graphqlQueries), ast.Dump(queries)
+			if got != want {
+				// TODO: nice diffing
+				t.Errorf("got:\n%v\nwant:\n%v\n", got, want)
+			}
+		})
+	}
+}

generate/testdata/parsing/fragments.go

@@ -0,0 +1,46 @@
+package parsing
+
+const MyFragment = `
+	# @genqlient
+	fragment MyFragment on MyType {
+		myFragmentField
+		...NestedFragment
+	}
+`
+
+var _ = `
+	# @genqlient
+	fragment NestedFragment on MyType {
+		myOtherFragmentField
+	}
+`
+
+const MyQuery = `
+	# @genqlient
+	query MyQuery {
+		myField
+		myOtherField {
+		...MyFragment
+		}
+	}
+`
+
+func query(s string) {}
+
+func MyMutation() {
+	query(`
+		# @genqlient
+		mutation MyMutation {
+			myField
+			myOtherField {
+			...MyFragment
+			}
+		}
+	`)
+}
+
+const (
+	NotAString = 1
+	NotAQuery  = `query
+		writing with GraphQL is fun!`
+)

generate/testdata/parsing/fragments.graphql

@@ -0,0 +1,19 @@
+query MyQuery {
+  myField
+  myOtherField {
+    ...MyFragment
+  }
+}
+
+fragment MyFragment on MyType {
+  myFragmentField
+  ...NestedFragment
+}
+
+fragment UnusedFragment on MyType {
+  myFragmentField
+}
+
+fragment NestedFragment on MyType {
+  myOtherFragmentField
+}

generate/testdata/parsing/fragments2.go

@@ -0,0 +1,8 @@
+package parsing
+
+const _ = `
+	# @genqlient
+	fragment UnusedFragment on MyType {
+		myFragmentField
+	}
+`

generate/testdata/parsing/fragments2.graphql

@@ -0,0 +1,6 @@
+mutation MyMutation {
+  myField
+  myOtherField {
+    ...MyFragment
+  }
+}