alps/plugin_go.go
2020-05-13 14:07:44 +02:00

141 lines
3.2 KiB
Go

package alps
import (
"html/template"
"net/http"
"path/filepath"
"github.com/labstack/echo/v4"
)
type goPlugin struct {
p *GoPlugin
}
func (p *goPlugin) Name() string {
return p.p.Name
}
func (p *goPlugin) LoadTemplate(t *template.Template) error {
t.Funcs(p.p.templateFuncs)
paths, err := filepath.Glob(PluginDir + "/" + p.p.Name + "/public/*.html")
if err != nil {
return err
}
if len(paths) > 0 {
if _, err := t.ParseFiles(paths...); err != nil {
return err
}
}
return nil
}
func (p *goPlugin) SetRoutes(group *echo.Group) {
for _, r := range p.p.routes {
h := r.Handler
group.Add(r.Method, r.Path, func(ectx echo.Context) error {
return h(ectx.(*Context))
})
}
group.Static("/plugins/"+p.p.Name+"/assets", PluginDir+"/"+p.p.Name+"/public/assets")
}
func (p *goPlugin) Inject(ctx *Context, name string, data RenderData) error {
if f, ok := p.p.injectFuncs["*"]; ok {
if err := f(ctx, data); err != nil {
return err
}
}
if f, ok := p.p.injectFuncs[name]; ok {
return f(ctx, data)
}
return nil
}
func (p *goPlugin) Close() error {
return nil
}
type goPluginRoute struct {
Method string
Path string
Handler HandlerFunc
}
// GoPlugin is a helper to create Go plugins.
//
// Use this struct to define your plugin, then call RegisterPluginLoader:
//
// p := GoPlugin{Name: "my-plugin"}
// // Define routes, template functions, etc
// alps.RegisterPluginLoader(p.Loader())
type GoPlugin struct {
Name string
routes []goPluginRoute
templateFuncs template.FuncMap
injectFuncs map[string]InjectFunc
}
// HandlerFunc is a function serving HTTP requests.
type HandlerFunc func(*Context) error
// AddRoute registers a new HTTP route.
func (p *GoPlugin) AddRoute(method, path string, handler HandlerFunc) {
p.routes = append(p.routes, goPluginRoute{method, path, handler})
}
func (p *GoPlugin) DELETE(path string, handler HandlerFunc) {
p.AddRoute(http.MethodDelete, path, handler)
}
func (p *GoPlugin) GET(path string, handler HandlerFunc) {
p.AddRoute(http.MethodGet, path, handler)
}
func (p *GoPlugin) POST(path string, handler HandlerFunc) {
p.AddRoute(http.MethodPost, path, handler)
}
func (p *GoPlugin) PUT(path string, handler HandlerFunc) {
p.AddRoute(http.MethodPut, path, handler)
}
// TemplateFuncs registers new template functions.
func (p *GoPlugin) TemplateFuncs(funcs template.FuncMap) {
if p.templateFuncs == nil {
p.templateFuncs = make(template.FuncMap, len(funcs))
}
for k, f := range funcs {
p.templateFuncs[k] = f
}
}
// InjectFunc is a function that injects data prior to rendering a template.
type InjectFunc func(ctx *Context, data RenderData) error
// Inject registers a function to execute prior to rendering a template. The
// special name "*" matches any template.
func (p *GoPlugin) Inject(name string, f InjectFunc) {
if p.injectFuncs == nil {
p.injectFuncs = make(map[string]InjectFunc)
}
p.injectFuncs[name] = f
}
// Plugin returns an object implementing Plugin.
func (p *GoPlugin) Plugin() Plugin {
return &goPlugin{p}
}
// Loader returns a loader function for this plugin.
func (p *GoPlugin) Loader() PluginLoaderFunc {
return func(*Server) ([]Plugin, error) {
return []Plugin{p.Plugin()}, nil
}
}