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- package koushin
-
- import (
- "fmt"
- "html/template"
- "io"
- "io/ioutil"
- "os"
-
- "github.com/labstack/echo/v4"
- )
-
- const themesDir = "themes"
-
- // GlobalRenderData contains data available in all templates.
- type GlobalRenderData struct {
- LoggedIn bool
-
- // if logged in
- Username string
- // TODO: list of mailboxes
-
- // additional plugin-specific data
- Extra map[string]interface{}
- }
-
- // BaseRenderData is the base type for templates. It should be extended with
- // additional template-specific fields:
- //
- // type MyRenderData struct {
- // BaseRenderData
- // // add additional fields here
- // }
- type BaseRenderData struct {
- GlobalData GlobalRenderData
- // additional plugin-specific data
- Extra map[string]interface{}
- }
-
- // Global implements RenderData.
- func (brd *BaseRenderData) Global() *GlobalRenderData {
- return &brd.GlobalData
- }
-
- // RenderData is implemented by template data structs. It can be used to inject
- // additional data to all templates.
- type RenderData interface {
- // GlobalData returns a pointer to the global render data.
- Global() *GlobalRenderData
- }
-
- // NewBaseRenderData initializes a new BaseRenderData.
- //
- // It can be used by routes to pre-fill the base data:
- //
- // type MyRenderData struct {
- // BaseRenderData
- // // add additional fields here
- // }
- //
- // data := &MyRenderData{
- // BaseRenderData: *koushin.NewBaseRenderData(ctx),
- // // other fields...
- // }
- func NewBaseRenderData(ctx *Context) *BaseRenderData {
- global := GlobalRenderData{Extra: make(map[string]interface{})}
-
- if ctx.Session != nil {
- global.LoggedIn = true
- global.Username = ctx.Session.username
- }
-
- return &BaseRenderData{
- GlobalData: global,
- Extra: make(map[string]interface{}),
- }
- }
-
- type renderer struct {
- base *template.Template
- themes map[string]*template.Template
- defaultTheme string
- }
-
- func (r *renderer) Render(w io.Writer, name string, data interface{}, ectx echo.Context) error {
- // ectx is the raw *echo.context, not our own *Context
- ctx := ectx.Get("context").(*Context)
-
- for _, plugin := range ctx.Server.Plugins {
- if err := plugin.Inject(ctx, name, data.(RenderData)); err != nil {
- return fmt.Errorf("failed to run plugin '%v': %v", plugin.Name(), err)
- }
- }
-
- // TODO: per-user theme selection
- t := r.base
- if r.defaultTheme != "" {
- t = r.themes[r.defaultTheme]
- }
- return t.ExecuteTemplate(w, name, data)
- }
-
- func loadTheme(name string, base *template.Template) (*template.Template, error) {
- theme, err := base.Clone()
- if err != nil {
- return nil, err
- }
-
- theme, err = theme.ParseGlob(themesDir + "/" + name + "/*.html")
- if err != nil {
- return nil, err
- }
-
- return theme, nil
- }
-
- func loadTemplates(logger echo.Logger, defaultTheme string, plugins []Plugin) (*renderer, error) {
- base := template.New("")
-
- for _, p := range plugins {
- if err := p.LoadTemplate(base); err != nil {
- return nil, fmt.Errorf("failed to load template for plugin '%v': %v", p.Name(), err)
- }
- }
-
- themes := make(map[string]*template.Template)
-
- files, err := ioutil.ReadDir(themesDir)
- if err != nil && !os.IsNotExist(err) {
- return nil, err
- }
-
- for _, fi := range files {
- if !fi.IsDir() {
- continue
- }
-
- logger.Printf("Loading theme '%v'", fi.Name())
- var err error
- if themes[fi.Name()], err = loadTheme(fi.Name(), base); err != nil {
- return nil, fmt.Errorf("failed to load theme '%v': %v", fi.Name(), err)
- }
- }
-
- if defaultTheme != "" {
- if _, ok := themes[defaultTheme]; !ok {
- return nil, fmt.Errorf("failed to find default theme '%v'", defaultTheme)
- }
- }
-
- return &renderer{
- base: base,
- themes: themes,
- defaultTheme: defaultTheme,
- }, nil
- }
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