Implement basic API scoping

internal/dis/component/server/list/api.go

@@ -0,0 +1,71 @@
+package list
+
+import (
+	"context"
+	"net/http"
+	"time"
+
+	"github.com/FAU-CDI/wisski-distillery/internal/dis/component"
+	"github.com/FAU-CDI/wisski-distillery/internal/dis/component/auth"
+	"github.com/FAU-CDI/wisski-distillery/internal/dis/component/auth/api"
+	"github.com/FAU-CDI/wisski-distillery/internal/dis/component/auth/scopes"
+	"github.com/FAU-CDI/wisski-distillery/internal/status"
+)
+
+// API implements an API to list all instances
+type API struct {
+	component.Base
+	Dependencies struct {
+		ListInstances *ListInstances
+		Auth          *auth.Auth
+	}
+}
+
+func (lia *API) Routes() component.Routes {
+	return component.Routes{
+		Prefix: "/api/v1/instances/directory",
+		Exact:  true,
+	}
+}
+
+// APISystem represents a system returned by the api
+type APISystem struct {
+	Slug    string
+	URL     string
+	Tagline string
+
+	EntityCount int
+	BundleCount int
+	LastEdit    time.Time
+}
+
+func (a *API) HandleRoute(ctx context.Context, path string) (http.Handler, error) {
+	return &api.Handler[[]APISystem]{
+		Config: a.Config,
+		Auth:   a.Dependencies.Auth,
+
+		Methods: []string{"GET"},
+		Scope:   scopes.ScopeInstanceDirectory,
+
+		Handler: func(s string, r *http.Request) ([]APISystem, error) {
+			var statuses []status.WissKI
+			if a.Dependencies.ListInstances.ShouldShowList(r) {
+				statuses = a.Dependencies.ListInstances.infos.Get(nil)
+			}
+
+			if len(statuses) == 0 {
+				return []APISystem{}, nil
+			}
+
+			infos := make([]APISystem, len(statuses))
+			for i, status := range statuses {
+				infos[i].Slug = status.Slug
+				infos[i].URL = status.URL
+				infos[i].EntityCount = status.Statistics.Bundles.TotalCount()
+				infos[i].BundleCount = status.Statistics.Bundles.TotalBundles
+				infos[i].LastEdit = status.Statistics.Bundles.LastEdit().Time
+			}
+			return infos, nil
+		},
+	}, nil
+}

internal/dis/component/server/list/list.go

@@ -0,0 +1,130 @@
+package list
+
+import (
+	"context"
+	"net/http"
+
+	"github.com/FAU-CDI/wisski-distillery/internal/dis/component"
+	"github.com/FAU-CDI/wisski-distillery/internal/dis/component/auth"
+	"github.com/FAU-CDI/wisski-distillery/internal/dis/component/instances"
+	"github.com/FAU-CDI/wisski-distillery/internal/status"
+	"github.com/tkw1536/pkglib/lazy"
+	"golang.org/x/sync/errgroup"
+)
+
+// ListInstances holds information about all instances
+type ListInstances struct {
+	component.Base
+
+	names lazy.Lazy[map[string]struct{}] // instance names
+	infos lazy.Lazy[[]status.WissKI]     // list of home instances (updated via cron)
+
+	Dependencies struct {
+		Auth      *auth.Auth
+		Instances *instances.Instances
+	}
+}
+
+func (li *ListInstances) Names() map[string]struct{} {
+	return li.names.Get(nil)
+}
+
+func (li *ListInstances) Infos() []status.WissKI {
+	return li.infos.Get(nil)
+}
+
+// ShouldShowList determines if a list should be shown for the given request
+func (li *ListInstances) ShouldShowList(r *http.Request) bool {
+	allowPrivate := li.Config.Home.List.Private.Value
+	allowPublic := li.Config.Home.List.Public.Value
+
+	if allowPrivate == allowPublic {
+		return allowPrivate
+	}
+
+	user, _ := li.Dependencies.Auth.UserOf(r)
+	if user == nil {
+		return allowPublic
+	} else {
+		return allowPrivate
+	}
+}
+
+var (
+	_ component.Cronable = (*ListInstances)(nil)
+)
+
+func (li *ListInstances) TaskName() string {
+	return "instance list and status"
+}
+
+func (li *ListInstances) Cron(ctx context.Context) (err error) {
+	{
+		names, e := li.getNames(ctx)
+		if err == nil {
+			li.names.Set(names)
+		} else {
+			err = e
+		}
+	}
+
+	{
+		infos, e := li.getInfos(ctx)
+		if err == nil {
+			li.infos.Set(infos)
+		} else {
+			err = e
+		}
+	}
+
+	return
+}
+
+// getNames returns the names of the given instances
+func (li *ListInstances) getNames(ctx context.Context) (map[string]struct{}, error) {
+	wissKIs, err := li.Dependencies.Instances.All(ctx)
+	if err != nil {
+		return nil, err
+	}
+
+	names := make(map[string]struct{}, len(wissKIs))
+	for _, w := range wissKIs {
+		names[w.Slug] = struct{}{}
+	}
+	return names, nil
+}
+
+// getInfos returns the names of the given instances
+func (li *ListInstances) getInfos(ctx context.Context) ([]status.WissKI, error) {
+	// find all the WissKIs
+	wissKIs, err := li.Dependencies.Instances.All(ctx)
+	if err != nil {
+		return nil, err
+	}
+
+	infos := make([]status.WissKI, len(wissKIs))
+
+	// determine their infos
+	var eg errgroup.Group
+	for i, instance := range wissKIs {
+		i := i
+		wissKI := instance
+		eg.Go(func() (err error) {
+			infos[i], err = wissKI.Info().Information(ctx, false)
+			return
+		})
+	}
+	eg.Wait()
+
+	// filter them by those that are running and do not have prefixes excluded
+	infosF := infos[:0]
+	for _, info := range infos {
+		if info.NoPrefixes || !info.Running {
+			continue
+		}
+		infosF = append(infosF, info)
+	}
+
+	// and return them
+	return infos[:len(infosF):len(infosF)], nil
+}