feat: change jsonschema library, better error messages 2020 draft (#127)

* feat: change jsonschema library, better error messages 2020 draft

* fix test

go.mod

@@ -28,7 +28,7 @@ require (
 	github.com/davecgh/go-spew v1.1.1
 	github.com/google/go-cmp v0.5.8
 	github.com/google/go-github/v43 v43.0.0
-	github.com/xeipuuv/gojsonschema v1.2.0
+	github.com/santhosh-tekuri/jsonschema/v5 v5.0.0
 	golang.org/x/term v0.0.0-20210927222741-03fcf44c2211
 	gopkg.in/yaml.v3 v3.0.1
 )
@@ -102,8 +102,6 @@ require (
 	github.com/vmihailenco/msgpack/v5 v5.3.5 // indirect
 	github.com/vmihailenco/tagparser/v2 v2.0.0 // indirect
 	github.com/xanzy/ssh-agent v0.3.1 // indirect
-	github.com/xeipuuv/gojsonpointer v0.0.0-20180127040702-4e3ac2762d5f // indirect
-	github.com/xeipuuv/gojsonreference v0.0.0-20180127040603-bd5ef7bd5415 // indirect
 	github.com/yuin/goldmark v1.4.4 // indirect
 	github.com/yuin/goldmark-emoji v1.0.1 // indirect
 	github.com/zalando/go-keyring v0.2.1 // indirect
@@ -113,7 +111,7 @@ require (
 	golang.org/x/sys v0.0.0-20220622161953-175b2fd9d664 // indirect
 	golang.org/x/text v0.3.7 // indirect
 	google.golang.org/appengine v1.6.7 // indirect
-	google.golang.org/genproto v0.0.0-20210716133855-ce7ef5c701ea // indirect
+	google.golang.org/genproto v0.0.0-20220107163113-42d7afdf6368 // indirect
 	google.golang.org/grpc v1.42.0 // indirect
 	google.golang.org/protobuf v1.28.0 // indirect
 	gopkg.in/alexcesaro/statsd.v2 v2.0.0 // indirect

internal/codegen/tpl_stencil.go

@@ -8,6 +8,7 @@ package codegen
 import (
 	"bytes"
 	"context"
+	"encoding/json"
 	"fmt"
 	"io"
 	"os"
@@ -16,10 +17,11 @@ import (
 
 	"github.com/davecgh/go-spew/spew"
 	"github.com/getoutreach/stencil/internal/dotnotation"
+	"github.com/getoutreach/stencil/pkg/configuration"
 	"github.com/go-git/go-billy/v5/osfs"
 	"github.com/pkg/errors"
+	"github.com/santhosh-tekuri/jsonschema/v5"
 	"github.com/sirupsen/logrus"
-	"github.com/xeipuuv/gojsonschema"
 )
 
 // TplStencil contains the global functions available to a template for
@@ -167,7 +169,7 @@ func (s *TplStencil) Arg(pth string) (interface{}, error) {
 			v = []interface{}{}
 		case "boolean", "bool":
 			v = false
-		case "integer", "int":
+		case "integer", "int", "number":
 			v = 0
 		case "string":
 			v = ""
@@ -178,20 +180,54 @@ func (s *TplStencil) Arg(pth string) (interface{}, error) {
 
 	// validate the data
 	if arg.Schema != nil {
-		schema := gojsonschema.NewGoLoader(arg.Schema)
-		document := gojsonschema.NewGoLoader(v)
-		result, err := gojsonschema.Validate(schema, document)
-		if err != nil {
-			return nil, errors.Wrapf(err, "module %q argument %q validation failed", s.t.Module.Name, pth)
+		if err := s.validateArg(pth, &arg, v); err != nil {
+			return nil, err
 		}
+	}
+
+	return v, nil
+}
+
+// validateArg validates an argument against the schema
+func (s *TplStencil) validateArg(pth string, arg *configuration.Argument, v interface{}) error {
+	schemaBuf := new(bytes.Buffer)
+	if err := json.NewEncoder(schemaBuf).Encode(arg.Schema); err != nil {
+		return errors.Wrap(err, "failed to encode schema into JSON")
+	}
+
+	jsc := jsonschema.NewCompiler()
+	jsc.Draft = jsonschema.Draft2020
+
+	schemaURL := "manifest.yaml/arguments/" + pth
+	if err := jsc.AddResource(schemaURL, schemaBuf); err != nil {
+		return errors.Wrapf(err, "failed to add argument '%s' json schema to compiler", pth)
+	}
+
+	schema, err := jsc.Compile(schemaURL)
+	if err != nil {
+		return errors.Wrapf(err, "failed to compile argument '%s' schema", pth)
+	}
 
-		// return the invalid response
-		if !result.Valid() {
-			return nil, fmt.Errorf("module %q argument %q validation failed: %s", s.t.Module.Name, pth, result.Errors())
+	if err := schema.Validate(v); err != nil {
+		var validationError *jsonschema.ValidationError
+		if errors.As(err, &validationError) {
+			// If there's only one error, return it directly, otherwise
+			// return the full list of errors.
+			errs := validationError.DetailedOutput().Errors
+			out := ""
+			if len(errs) == 1 {
+				out = errs[0].Error
+			} else {
+				out = fmt.Sprintf("%#v", validationError.DetailedOutput().Errors)
+			}
+
+			return fmt.Errorf("module %q argument %q validation failed: %s", s.t.Module.Name, pth, out)
 		}
+
+		return errors.Wrapf(err, "module %q argument %q validation failed", s.t.Module.Name, pth)
 	}
 
-	return v, nil
+	return nil
 }
 
 // Deprecated: Use Arg instead.

internal/codegen/tpl_stencil_test.go

@@ -139,7 +139,7 @@ func TestTplStencil_Arg(t *testing.T) {
 			fields: fakeTemplate(t, map[string]interface{}{
 				"hello": map[string]interface{}{
 					"world": map[string]interface{}{
-						"abc": []string{"def"},
+						"abc": []interface{}{"def"},
 					},
 				},
 			}, map[string]configuration.Argument{
@@ -162,7 +162,7 @@ func TestTplStencil_Arg(t *testing.T) {
 			args: args{
 				pth: "hello",
 			},
-			want:    map[string]interface{}{"world": map[string]interface{}{"abc": []string{"def"}}},
+			want:    map[string]interface{}{"world": map[string]interface{}{"abc": []interface{}{"def"}}},
 			wantErr: false,
 		},
 		{