add jet template engine

examples/full/go.mod

@@ -19,6 +19,8 @@ require (
 	dario.cat/mergo v1.0.0 // indirect
 	github.com/AlekSi/pointer v1.2.0 // indirect
 	github.com/BurntSushi/toml v1.2.1 // indirect
+	github.com/CloudyKit/fastprinter v0.0.0-20200109182630-33d98a066a53 // indirect
+	github.com/CloudyKit/jet/v6 v6.2.0 // indirect
 	github.com/DataDog/appsec-internal-go v1.6.0 // indirect
 	github.com/DataDog/datadog-agent/pkg/obfuscate v0.48.0 // indirect
 	github.com/DataDog/datadog-agent/pkg/remoteconfig/state v0.48.1 // indirect

examples/full/go.sum

@@ -4,6 +4,10 @@ github.com/AlekSi/pointer v1.2.0 h1:glcy/gc4h8HnG2Z3ZECSzZ1IX1x2JxRVuDzaJwQE0+w=
 github.com/AlekSi/pointer v1.2.0/go.mod h1:gZGfd3dpW4vEc/UlyfKKi1roIqcCgwOIvb0tSNSBle0=
 github.com/BurntSushi/toml v1.2.1 h1:9F2/+DoOYIOksmaJFPw1tGFy1eDnIJXg+UHjuD8lTak=
 github.com/BurntSushi/toml v1.2.1/go.mod h1:CxXYINrC8qIiEnFrOxCa7Jy5BFHlXnUU2pbicEuybxQ=
+github.com/CloudyKit/fastprinter v0.0.0-20200109182630-33d98a066a53 h1:sR+/8Yb4slttB4vD+b9btVEnWgL3Q00OBTzVT8B9C0c=
+github.com/CloudyKit/fastprinter v0.0.0-20200109182630-33d98a066a53/go.mod h1:+3IMCy2vIlbG1XG/0ggNQv0SvxCAIpPM5b1nCz56Xno=
+github.com/CloudyKit/jet/v6 v6.2.0 h1:EpcZ6SR9n28BUGtNJSvlBqf90IpjeFr36Tizxhn/oME=
+github.com/CloudyKit/jet/v6 v6.2.0/go.mod h1:d3ypHeIRNo2+XyqnGA8s+aphtcVpjP5hPwP/Lzo7Ro4=
 github.com/DataDog/appsec-internal-go v1.6.0 h1:QHvPOv/O0s2fSI/BraZJNpRDAtdlrRm5APJFZNBxjAw=
 github.com/DataDog/appsec-internal-go v1.6.0/go.mod h1:pEp8gjfNLtEOmz+iZqC8bXhu0h4k7NUsW/qiQb34k1U=
 github.com/DataDog/datadog-agent/pkg/obfuscate v0.48.0 h1:bUMSNsw1iofWiju9yc1f+kBd33E3hMJtq9GuU602Iy8=

go.mod

@@ -3,6 +3,7 @@ module github.com/rebuy-de/rebuy-go-sdk/v8
 go 1.22.0
 
 require (
+	github.com/CloudyKit/jet/v6 v6.2.0
 	github.com/afiskon/promtail-client v0.0.0-20190305142237-506f3f921e9c
 	github.com/alicebob/miniredis/v2 v2.31.1
 	github.com/aws/aws-sdk-go-v2 v1.25.0
@@ -49,6 +50,7 @@ require (
 	dario.cat/mergo v1.0.0 // indirect
 	github.com/AlekSi/pointer v1.2.0 // indirect
 	github.com/BurntSushi/toml v1.2.1 // indirect
+	github.com/CloudyKit/fastprinter v0.0.0-20200109182630-33d98a066a53 // indirect
 	github.com/DataDog/appsec-internal-go v1.6.0 // indirect
 	github.com/DataDog/datadog-agent/pkg/obfuscate v0.48.0 // indirect
 	github.com/DataDog/datadog-agent/pkg/remoteconfig/state v0.48.1 // indirect

go.sum

@@ -4,6 +4,10 @@ github.com/AlekSi/pointer v1.2.0 h1:glcy/gc4h8HnG2Z3ZECSzZ1IX1x2JxRVuDzaJwQE0+w=
 github.com/AlekSi/pointer v1.2.0/go.mod h1:gZGfd3dpW4vEc/UlyfKKi1roIqcCgwOIvb0tSNSBle0=
 github.com/BurntSushi/toml v1.2.1 h1:9F2/+DoOYIOksmaJFPw1tGFy1eDnIJXg+UHjuD8lTak=
 github.com/BurntSushi/toml v1.2.1/go.mod h1:CxXYINrC8qIiEnFrOxCa7Jy5BFHlXnUU2pbicEuybxQ=
+github.com/CloudyKit/fastprinter v0.0.0-20200109182630-33d98a066a53 h1:sR+/8Yb4slttB4vD+b9btVEnWgL3Q00OBTzVT8B9C0c=
+github.com/CloudyKit/fastprinter v0.0.0-20200109182630-33d98a066a53/go.mod h1:+3IMCy2vIlbG1XG/0ggNQv0SvxCAIpPM5b1nCz56Xno=
+github.com/CloudyKit/jet/v6 v6.2.0 h1:EpcZ6SR9n28BUGtNJSvlBqf90IpjeFr36Tizxhn/oME=
+github.com/CloudyKit/jet/v6 v6.2.0/go.mod h1:d3ypHeIRNo2+XyqnGA8s+aphtcVpjP5hPwP/Lzo7Ro4=
 github.com/DataDog/appsec-internal-go v1.6.0 h1:QHvPOv/O0s2fSI/BraZJNpRDAtdlrRm5APJFZNBxjAw=
 github.com/DataDog/appsec-internal-go v1.6.0/go.mod h1:pEp8gjfNLtEOmz+iZqC8bXhu0h4k7NUsW/qiQb34k1U=
 github.com/DataDog/datadog-agent/pkg/obfuscate v0.48.0 h1:bUMSNsw1iofWiju9yc1f+kBd33E3hMJtq9GuU602Iy8=

migrations.md

@@ -241,3 +241,64 @@ There is not guarantee that this work, tho.
 
 * Use the pattern `return fmt.Errorf("something happenend with %#v: %w", someID, err)`
 * The stack trace feature gets lost. Therefore it is suggested to properly add error messages each time handling errors.
+
+
+## 2024-07-05 Switch to Jet Templates
+
+### Reasoning
+
+The builtin template engine has some shortcommings like being able to pass multiple and optional parameters to a template fragment. For example this block definition is not possible to builtin template engine:
+
+```
+{{ block entityLink(label, id, tab, extraClasses) }}
+  {{ e := findEntity(.) }}
+  <a class="ry-nowrap ry-underline {{ extraClasses }}" href="/{{.}}{{if id}}/{{id}}{{end}}{{ if tab }}/{{tab}}{{end}}">
+    <span class="icon">
+      <i class="fa-solid {{ e.IconClasses }}"></i>
+    </span>
+    {{ if label }}
+    <span>{{ label }}</span>
+    {{ else if id }}
+    <span>{{ id }}</span>
+    {{ else }}
+    <span>{{ e.Plural }}</span>
+    {{ end }}
+  </a>
+{{ end }}
+```
+
+### Hints
+
+* The handler function signatures changed from `func(*webutil.View, *http.Request) webutil.Response` to `func(*http.Request) webutil.Response`.
+* Wrap function changes from `webutil.ViewHandler.Wrap` to `webutil.WrapView`.
+* Since the `View` interface is not part of the function signature, it needs to be added to the struct where the handler function is attached to.
+* Non-HTML responses are now created with functions directly from the `webutil` package. For example `return webutilext.ViewError(http.StatusInternalServerError, err)` instead of `return v.Error(http.StatusBadRequest, fmt.Errorf(`unknown value for "until"`))`. where `v` was passed to the handler.
+
+### Examples
+
+Jet Set for Development:
+
+```go
+jet.NewSet(
+	jet.NewOSFileSystemLoader("./pkg/app/web/templates"),
+	jet.InDevelopmentMode(),
+)
+```
+
+Jet Set for Production:
+
+```go
+jet.NewSet(
+	webutil.JetFSLoader{FS: templateFS},
+)
+```
+
+Jet Viewer based on Jet Set:
+
+```go
+webutilext.NewJetViewer(
+	js,
+	webutil.JetVarOption("clusterName", cn),
+	webutil.JetVarOption("assetPath", "/assets/"+prefix),
+)
+```

pkg/webutil/auth.go

@@ -312,6 +312,8 @@ func DevAuthMiddleware(roles ...string) func(http.Handler) http.Handler {
 //	{{ else }}
 //	  <a class="nav-link" href="/auth/login">Login</span></a>
 //	{{ end }}
+//
+// Deprecated: use AuthJetOptions
 func AuthTemplateFunctions(r *http.Request) template.FuncMap {
 	authenticated := true
 	info := AuthInfoFromRequest(r)
@@ -329,6 +331,17 @@ func AuthTemplateFunctions(r *http.Request) template.FuncMap {
 	}
 }
 
+func AuthJetOptions() JetOption {
+	return JetOptions(
+		WithRequestVar("AuthIsAuthenticated", func(r *http.Request) bool {
+			return AuthInfoFromRequest(r) != nil
+		}),
+		WithRequestVar("AuthInfo", func(r *http.Request) *AuthInfo {
+			return AuthInfoFromRequest(r)
+		}),
+	)
+}
+
 // AuthInfoFromContext extracts the AuthInfo from the given context. The
 // AuthInfo is injected into the request via the AuthMiddleware. Therefore it
 // is required to use this middleware to be able to get the AuthInfo.

pkg/webutil/view.go

@@ -12,11 +12,13 @@ import (
 	"github.com/sirupsen/logrus"
 )
 
+// Deprecated: Use webutil.JetViewer or webutil.GoTemplateViewer
 type ViewHandler struct {
 	FS       fs.FS
 	FuncMaps []TemplateFuncMap
 }
 
+// Deprecated: Use webutil.JetViewer or webutil.GoTemplateViewer
 func NewViewHandler(fs fs.FS, fms ...TemplateFuncMap) *ViewHandler {
 	v := &ViewHandler{
 		FS:       fs,
@@ -26,6 +28,7 @@ func NewViewHandler(fs fs.FS, fms ...TemplateFuncMap) *ViewHandler {
 	return v
 }
 
+// Deprecated: Use webutil.JetViewer or webutil.GoTemplateViewer
 type ResponseHandlerFunc func(*View, *http.Request) Response
 
 func (h *ViewHandler) Wrap(fn ResponseHandlerFunc) http.HandlerFunc {
@@ -62,6 +65,7 @@ func SimpleTemplateFuncMap(name string, fn interface{}) TemplateFuncMap {
 	}
 }
 
+// Deprecated
 func SimpleTemplateFuncMaps(fm template.FuncMap) TemplateFuncMap {
 	return func(_ *http.Request) template.FuncMap {
 		return fm

pkg/webutil/viewfuncs.go

@@ -0,0 +1,80 @@
+package webutil
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+
+	"github.com/pkg/errors"
+	"github.com/sirupsen/logrus"
+)
+
+func WrapView(fn func(*http.Request) Response) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		fn(r)(w, r)
+	}
+}
+
+func ViewError(status int, err error) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		l := logrus.
+			WithField("stacktrace", fmt.Sprintf("%+v", err)).
+			WithError(errors.WithStack(err))
+
+		if errors.Is(err, context.Canceled) {
+			l.Debugf("request cancelled: %s", err)
+
+			// The code is copied from nginx, where it means that the client
+			// closed the connection. It is necessary to alter the status code,
+			// because DataDog will report errors, if the code is >=500,
+			// regardless of the connection state.
+			status = 499
+		} else if status >= 500 {
+			l.Errorf("request failed: %s", err)
+		} else {
+			l.Warnf("request failed: %s", err)
+		}
+
+		w.WriteHeader(status)
+		fmt.Fprint(w, err.Error())
+	}
+}
+
+func ViewErrorf(status int, text string, a ...interface{}) http.HandlerFunc {
+	return ViewError(status, fmt.Errorf(text, a...))
+}
+
+func ViewRedirect(status int, location string, args ...interface{}) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		url := fmt.Sprintf(location, args...)
+		http.Redirect(w, r, url, status)
+	}
+}
+
+func ViewJSON(status int, data any) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		buf := new(bytes.Buffer)
+		enc := json.NewEncoder(buf)
+		enc.SetIndent("", "    ")
+
+		err := enc.Encode(data)
+		if err != nil {
+			ViewError(http.StatusInternalServerError, err)(w, r)
+			return
+		}
+
+		w.Header().Set("Content-Type", "application/json; charset=utf-8")
+		w.WriteHeader(status)
+		buf.WriteTo(w)
+	}
+}
+
+func ViewInlineHTML(status int, data string, a ...any) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "text/html; charset=utf-8")
+		w.WriteHeader(status)
+		fmt.Fprintf(w, data, a...)
+	}
+}

pkg/webutil/viewgo.go

@@ -0,0 +1,43 @@
+package webutil
+
+import (
+	"bytes"
+	"html/template"
+	"io/fs"
+	"net/http"
+
+	"github.com/pkg/errors"
+)
+
+type GoTemplateViewer struct {
+	fs       fs.FS
+	funcMaps []TemplateFuncMap
+}
+
+func NewGoTemplateViewer(fs fs.FS, fms ...TemplateFuncMap) *GoTemplateViewer {
+	return &GoTemplateViewer{
+		FS:       fs,
+		FuncMaps: fms,
+	}
+}
+
+func (v *GoTemplateViewer) HTML(status int, filename string, data any) http.HandlerFunc {
+}
+
+func (v *GoTemplateViewer) Render(filename string, r *http.Request, data any) (*bytes.Buffer, error) {
+	t := template.New(filename)
+
+	for _, fm := range h.FuncMaps {
+		t = t.Funcs(fm(r))
+	}
+
+	t, err := t.ParseFS(h.FS, "*")
+	if err != nil {
+		return nil, errors.Wrap(err, "parsing template failed")
+	}
+
+	buf := new(bytes.Buffer)
+	err = t.Execute(buf, data)
+
+	return buf, errors.Wrap(err, "executing template failed")
+}

pkg/webutil/viewjet.go

@@ -0,0 +1,93 @@
+package webutil
+
+import (
+	"io"
+	"io/fs"
+	"net/http"
+	"reflect"
+	"strings"
+
+	"github.com/CloudyKit/jet/v6"
+	"gopkg.in/DataDog/dd-trace-go.v1/ddtrace/ext"
+	"gopkg.in/DataDog/dd-trace-go.v1/ddtrace/tracer"
+)
+
+type JetViewer struct {
+	views   *jet.Set
+	options []JetOption
+}
+
+func NewJetViewer(js *jet.Set, options ...JetOption) *JetViewer {
+	jv := &JetViewer{
+		views:   js,
+		options: options,
+	}
+
+	jv.views.AddGlobal("contains", strings.Contains)
+
+	jv.views.AddGlobalFunc("deref", func(a jet.Arguments) reflect.Value {
+		a.RequireNumOfArguments("pointer", 1, 1)
+		v := a.Get(0)
+		if v.Kind() == reflect.Ptr {
+			return v.Elem()
+		}
+
+		return v
+	})
+
+	return jv
+}
+
+func (j *JetViewer) HTML(status int, filename string, data any, opts ...JetOption) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		span, ctx := tracer.StartSpanFromContext(
+			r.Context(), "render",
+			tracer.Tag(ext.ResourceName, filename),
+			tracer.Tag(ext.SpanKind, ext.SpanKindInternal),
+		)
+		r = r.WithContext(ctx)
+		defer span.Finish()
+
+		w.Header().Set("Content-Type", "text/html; charset=utf-8")
+		view, err := j.views.GetTemplate(filename)
+		if err != nil {
+			ViewError(http.StatusInternalServerError, err)(w, r)
+			return
+		}
+
+		vars := make(jet.VarMap)
+		vars.Set("currentURLPath", r.URL.Path)
+
+		for _, o := range j.options {
+			o(r, &vars)
+		}
+
+		for _, o := range opts {
+			o(r, &vars)
+		}
+
+		err = view.Execute(w, vars, data)
+		if err != nil {
+			ViewError(http.StatusInternalServerError, err)(w, r)
+			return
+		}
+	}
+}
+
+type JetFSLoader struct {
+	fs.FS
+}
+
+func (l JetFSLoader) Exists(path string) bool {
+	f, err := l.Open(path)
+	if err != nil {
+		return false
+	}
+	f.Close()
+	return true
+}
+
+func (l JetFSLoader) Open(path string) (io.ReadCloser, error) {
+	path = strings.TrimLeft(path, "/")
+	return l.FS.Open(path)
+}