Use vendor when building (#201)

* Use vendor code for all go calls

* Add missing vendor dependencies

* Add travis_retry to yarn install

* Fix go test call

vendor/github.com/99designs/gqlgen/api/generate.go

@@ -0,0 +1,76 @@
+package api
+
+import (
+	"syscall"
+
+	"github.com/99designs/gqlgen/codegen"
+	"github.com/99designs/gqlgen/codegen/config"
+	"github.com/99designs/gqlgen/plugin"
+	"github.com/99designs/gqlgen/plugin/modelgen"
+	"github.com/99designs/gqlgen/plugin/resolvergen"
+	"github.com/pkg/errors"
+	"golang.org/x/tools/go/packages"
+)
+
+func Generate(cfg *config.Config, option ...Option) error {
+	_ = syscall.Unlink(cfg.Exec.Filename)
+	_ = syscall.Unlink(cfg.Model.Filename)
+
+	plugins := []plugin.Plugin{
+		modelgen.New(),
+		resolvergen.New(),
+	}
+
+	for _, o := range option {
+		o(cfg, &plugins)
+	}
+
+	for _, p := range plugins {
+		if mut, ok := p.(plugin.ConfigMutator); ok {
+			err := mut.MutateConfig(cfg)
+			if err != nil {
+				return errors.Wrap(err, p.Name())
+			}
+		}
+	}
+	// Merge again now that the generated models have been injected into the typemap
+	data, err := codegen.BuildData(cfg)
+	if err != nil {
+		return errors.Wrap(err, "merging failed")
+	}
+
+	if err = codegen.GenerateCode(data); err != nil {
+		return errors.Wrap(err, "generating core failed")
+	}
+
+	for _, p := range plugins {
+		if mut, ok := p.(plugin.CodeGenerator); ok {
+			err := mut.GenerateCode(data)
+			if err != nil {
+				return errors.Wrap(err, p.Name())
+			}
+		}
+	}
+
+	if err := validate(cfg); err != nil {
+		return errors.Wrap(err, "validation failed")
+	}
+
+	return nil
+}
+
+func validate(cfg *config.Config) error {
+	roots := []string{cfg.Exec.ImportPath()}
+	if cfg.Model.IsDefined() {
+		roots = append(roots, cfg.Model.ImportPath())
+	}
+
+	if cfg.Resolver.IsDefined() {
+		roots = append(roots, cfg.Resolver.ImportPath())
+	}
+	_, err := packages.Load(&packages.Config{Mode: packages.LoadTypes | packages.LoadSyntax}, roots...)
+	if err != nil {
+		return errors.Wrap(err, "validation failed")
+	}
+	return nil
+}