'wdcli backup': Rework backup process

This commit reworks the backup process to dynamically find the list of
components.

internal/component/control/backup.go

@@ -0,0 +1,48 @@
+package control
+
+import (
+	"io/fs"
+	"os"
+	"path/filepath"
+
+	"github.com/FAU-CDI/wisski-distillery/pkg/fsx"
+	"github.com/tkw1536/goprogram/stream"
+)
+
+func (*Control) BackupName() string {
+	return "config"
+}
+
+// Backup backups all control plane configuration files into dest
+func (control *Control) Backup(io stream.IOStream, dest string) error {
+	// create the destination directory, TODO: outsource this
+	if err := os.Mkdir(dest, fs.ModeDir); err != nil {
+		return err
+	}
+
+	files := control.backupFiles()
+	for _, src := range files {
+		dst := filepath.Join(dest, filepath.Base(src)) // destination path
+
+		// if the src file does not exist, don't copy it!
+		if !fsx.IsFile(src) { // TODO: log this somewhere
+			continue
+		}
+
+		if err := fsx.CopyFile(dst, src); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+// backupfiles lists the files to be backed up.
+func (control *Control) backupFiles() []string {
+	return []string{
+		control.Config.ConfigPath,
+		control.Config.ExecutablePath(),
+		control.Config.SelfOverridesFile,
+		control.Config.GlobalAuthorizedKeysFile,
+	}
+}

internal/component/control/control.env

@@ -0,0 +1,9 @@
+VIRTUAL_HOST=${VIRTUAL_HOST}
+
+LETSENCRYPT_HOST=${LETSENCRYPT_HOST}
+LETSENCRYPT_EMAIL=${LETSENCRYPT_EMAIL}
+
+CONFIG_PATH=${CONFIG_PATH}
+DEPLOY_ROOT=${DEPLOY_ROOT}
+GLOBAL_AUTHORIZED_KEYS_FILE=${GLOBAL_AUTHORIZED_KEYS_FILE}
+SELF_OVERRIDES_FILE=${SELF_OVERRIDES_FILE}

internal/component/control/control.go

@@ -0,0 +1,54 @@
+package control
+
+import (
+	"embed"
+
+	"github.com/FAU-CDI/wisski-distillery/internal/component"
+	"github.com/FAU-CDI/wisski-distillery/internal/component/instances"
+	"github.com/FAU-CDI/wisski-distillery/internal/core"
+)
+
+// Control represents the control server
+type Control struct {
+	component.ComponentBase
+
+	Instances *instances.Instances
+
+	ResolverFile string
+}
+
+func (control Control) Name() string {
+	return "dis" // TODO: Rename this to control!
+}
+
+//go:embed all:control control.env
+var resources embed.FS
+
+func (control Control) Stack() component.StackWithResources {
+	return control.ComponentBase.MakeStack(component.StackWithResources{
+		Resources:   resources,
+		ContextPath: "control",
+		EnvPath:     "control.env",
+
+		EnvContext: map[string]string{
+			"VIRTUAL_HOST":      control.Config.DefaultHost(),
+			"LETSENCRYPT_HOST":  control.Config.DefaultSSLHost(),
+			"LETSENCRYPT_EMAIL": control.Config.CertbotEmail,
+
+			"CONFIG_PATH": control.Config.ConfigPath,
+			"DEPLOY_ROOT": control.Config.DeployRoot,
+
+			"GLOBAL_AUTHORIZED_KEYS_FILE": control.Config.GlobalAuthorizedKeysFile,
+			"SELF_OVERRIDES_FILE":         control.Config.SelfOverridesFile,
+		},
+
+		TouchFiles:       []string{control.ResolverFile},
+		CopyContextFiles: []string{core.Executable},
+	})
+}
+
+func (control Control) Context(parent component.InstallationContext) component.InstallationContext {
+	return component.InstallationContext{
+		core.Executable: control.Config.CurrentExecutable(),
+	}
+}

internal/component/control/control/Dockerfile

@@ -0,0 +1,5 @@
+FROM docker.io/library/docker:20.10-cli
+
+COPY wdcli /wdcli
+EXPOSE 8888
+CMD ["/wdcli","--internal-in-docker","server","--bind","0.0.0.0:8888"]

internal/component/control/control/docker-compose.yml

@@ -0,0 +1,29 @@
+version: "3.7"
+
+services:
+  dis:
+    build: .
+    restart: always
+    environment:
+      # port and hostname for this image to use
+      VIRTUAL_HOST: ${VIRTUAL_HOST}
+      VIRTUAL_PORT: 8888
+
+      CONFIG_PATH: ${CONFIG_PATH}
+      
+      # optional letsencrypt email
+      LETSENCRYPT_HOST: ${LETSENCRYPT_HOST}
+      LETSENCRYPT_EMAIL: ${LETSENCRYPT_EMAIL}
+
+    volumes:
+      # TODO: Mount docker socket properly!
+      - "/var/run/docker.sock:/var/run/docker.sock"
+      - "${CONFIG_PATH}:${CONFIG_PATH}:ro"
+      - "${DEPLOY_ROOT}:${DEPLOY_ROOT}:ro"
+      - "${GLOBAL_AUTHORIZED_KEYS_FILE}:${GLOBAL_AUTHORIZED_KEYS_FILE}:ro"
+      - "${SELF_OVERRIDES_FILE}:${SELF_OVERRIDES_FILE}:ro"
+
+networks:
+  default:
+    name: distillery
+    external: true

internal/component/control/html/index.html

@@ -0,0 +1,55 @@
+<!DOCTYPE html>
+<link rel="stylesheet" href="/dis/static/dis.css">
+<link rel="stylesheet" href="/dis/static/autolink.css">
+
+<title>Distillery Status Page</title>
+<h1 id="top">Distillery Status Page</h1>
+
+<h2 id="overview">Overview</h2>
+
+<p>
+    <b>Domain:</b> <code>{{.Config.DefaultDomain}}</code> <br />
+    <b>Legacy Domain(s):</b> <code>{{.Config.SelfExtraDomains}}</code><br />
+    <b>HTTPS Email:</b> <code>{{.Config.CertbotEmail}}</code><br />
+    <hr />
+    <b>Homepage Redirect:</b><a href="{{.Config.SelfRedirect}}" target="_blank" rel="noopener noreferrer">{{.Config.SelfRedirect}}</a><br />
+    <hr />
+    <b>Backup Age:</b> <code>{{.Config.MaxBackupAge}}</code> Day(s)<br />
+    <hr />
+    <b>Base Directory:</b> <code>{{.Config.DeployRoot}}</code><br />
+    <b>Configuration File:</b> <code>{{.Config.ConfigPath}}</code><br />
+    <b>Authorized_Keys File:</b> <code>{{.Config.GlobalAuthorizedKeysFile}}</code><br />
+    <hr />
+    <b>MySQL User Prefix:</b> <code>{{.Config.MysqlUserPrefix}}</code><br />
+    <b>MySQL Database Prefix:</b> <code>{{.Config.MysqlDatabasePrefix}}</code><br />
+    <b>GraphDB User Prefix:</b> <code>{{.Config.GraphDBUserPrefix}}</code><br />
+    <b>GraphDB Database Prefix:</b> <code>{{.Config.GraphDBRepoPrefix}}</code><br />
+    <hr />
+    <b>Bookkeeping Database:</b> <code>{{.Config.DistilleryBookkeepingDatabase}}</code><br />
+    <b>Bookkeeping Table:</b> <code>{{.Config.DistilleryBookkeepingTable}}</code><br />
+</p>
+
+<h2 id="instances">Instances</h2>
+
+<p>
+    <code>{{ .TotalCount }}</code> instance(s) = <code>{{ .RunningCount }}</code> running + <code>{{ .StoppedCount }}</code> stopped<br />
+</p>
+
+{{range .Instances}}
+<div class="wisski {{ if .Running }}running{{ else }}stopped{{ end }}">
+    <h3 id="instance-{{.Slug}}">{{.Slug}}{{ if not .Running }}&nbsp;<small>not running</small>{{ end }}</h3>
+    <p>
+        <a href="{{.URL}}" target="_blank" rel="noopener noreferrer">{{.URL}}</a><br />
+
+        <small>
+            <a href="/dis/instance/{{.Slug}}">More Details</a>
+        </small>
+    </p>
+</div>
+{{end}}
+
+<footer>
+    Generated at <code>{{ .Time }}</code>
+</footer>
+
+<script src="/dis/static/autolink.js"></script>

internal/component/control/html/instance.html

@@ -0,0 +1,36 @@
+<!DOCTYPE html>
+<link rel="stylesheet" href="/dis/static/dis.css">
+<link rel="stylesheet" href="/dis/static/autolink.css">
+
+<title>Distillery Status Page - {{ .Info.Slug }}</title>
+<h1 id="top">Distillery Status Page - {{ .Info.Slug }}</h1>
+<p>
+    <a href="/dis/index">Back to index</a>
+</p>
+
+<p>
+    <b>Slug:</b> <code>{{ .Info.Slug }}</code> <br />
+    <b>URL:</b> <a href="{{ .Info.URL }}" target="_blank" rel="noopener noreferrer">{{ .Info.URL }}</a> <br />
+    <hr />
+    <b>Running:</b> <code>{{ .Info.Running }}</code> <br />
+    <hr />
+    <b>Created:</b> <code>{{ .Instance.Created }}</code> <br />
+    <b>OwnerEmail:</b> <code>{{ .Instance.OwnerEmail }}</code> <br />
+    <hr />
+    <b>FilesystemBase:</b> <code>{{ .Instance.FilesystemBase }}</code> <br />
+    <b>AutoBlindUpdateEnabled:</b> <code>{{ .Instance.AutoBlindUpdateEnabled }}</code> <br />
+    <hr />
+    <b>Pathbuilders:</b> <code>{{ .Info.Pathbuilders }}</code> <br />
+    <hr />
+	<b>SqlDatabase:</b> <code>{{ .Instance.SqlDatabase }}</code> <br />
+	<b>SqlUsername:</b> <code>{{ .Instance.SqlUsername }}</code> <br />
+    <hr />
+	<b>GraphDBRepository:</b> <code>{{ .Instance.GraphDBRepository }}</code> <br />
+	<b>GraphDBUsername:</b> <code>{{ .Instance.GraphDBUsername }}</code> <br />
+</p>
+
+<footer>
+    Generated at <code>{{ .Time }}</code>
+</footer>
+
+<script src="/dis/static/autolink.js"></script>

internal/component/control/html/static/autolink.css

@@ -0,0 +1,20 @@
+.header-link {
+    position: relative;
+    left: 0.5em;
+    opacity: 0;
+    font-size: 0.8em;
+
+    -webkit-transition: opacity 0.2s ease-in-out 0.1s;
+    -moz-transition: opacity 0.2s ease-in-out 0.1s;
+    -ms-transition: opacity 0.2s ease-in-out 0.1s;
+
+    text-decoration: none;
+}
+
+h2:hover .header-link,
+h3:hover .header-link,
+h4:hover .header-link,
+h5:hover .header-link,
+h6:hover .header-link {
+    opacity: 1;
+}

internal/component/control/html/static/autolink.js

@@ -0,0 +1,24 @@
+/** adding links to each item, see http://blog.parkermoore.de/2014/08/01/header-anchor-links-in-vanilla-javascript-for-github-pages-and-jekyll/ */
+var anchorForId = function (id) {
+    var anchor = document.createElement("a");
+    anchor.className = "header-link";
+    anchor.href = "#" + id;
+    anchor.innerHTML = "#";
+    return anchor;
+};
+
+var linkifyAnchors = function (level) {
+    var headers = document.getElementsByTagName("h" + level);
+    for (var h = 0; h < headers.length; h++) {
+        var header = headers[h];
+
+        if (typeof header.id !== "undefined" && header.id !== "") {
+            header.appendChild(anchorForId(header.id));
+        }
+    }
+};
+
+
+for (var level = 1; level <= 6; level++) {
+    linkifyAnchors(level);
+}

internal/component/control/html/static/dis.css

@@ -0,0 +1,67 @@
+html {
+    line-height: 1.5;
+    font-family: Roboto;
+    font-size: 20px;
+    color: #1a1a1a;
+    background-color: #fdfdfd;
+}
+body {
+    margin: 0 auto;
+    max-width: 36em;
+    padding-left: 50px;
+    padding-right: 50px;
+    padding-top: 50px;
+    padding-bottom: 50px;
+    hyphens: auto;
+    overflow-wrap: break-word;
+    text-rendering: optimizeLegibility;
+    font-kerning: normal;
+}
+
+@media (max-width: 600px) {
+    body {
+        font-size: 0.9em;
+        padding: 1em;
+    }
+}
+
+h1 {
+    margin-top: 1.4em;
+}
+
+h2,h3 {
+    margin-top: 1em;    
+}
+
+code {
+    font-family: Roboto Mono;
+    color: blue;
+}
+
+p {
+    margin: 1em 0;
+    text-align: justify;
+}
+
+a, a:visited {
+    color: #1a1a1a;
+}
+
+footer {
+    border-top: 1px solid #1a1a1a;
+    font-size: small;
+    text-align: center;
+}
+
+.wisski {
+    padding-left: 5px;
+}
+
+.wisski.running {
+    background-color: green;
+}
+
+.wisski.stopped {
+    background-color: red;
+}
+

internal/component/control/info.go

@@ -0,0 +1,196 @@
+package control
+
+import (
+	"embed"
+	"html/template"
+	"io/fs"
+	"net/http"
+	"strings"
+	"time"
+
+	"github.com/FAU-CDI/wisski-distillery/internal/bookkeeping"
+	"github.com/FAU-CDI/wisski-distillery/internal/component/instances"
+	"github.com/FAU-CDI/wisski-distillery/internal/config"
+	"github.com/FAU-CDI/wisski-distillery/pkg/httpx"
+	"github.com/tkw1536/goprogram/stream"
+	"golang.org/x/sync/errgroup"
+)
+
+func (control *Control) info(io stream.IOStream) (http.Handler, error) {
+	mux := http.NewServeMux()
+
+	// handle everything under /dis/!
+	mux.HandleFunc("/dis/", func(w http.ResponseWriter, r *http.Request) {
+		if r.URL.Path == "/dis/" {
+			http.Redirect(w, r, "/dis/index", http.StatusTemporaryRedirect)
+			return
+		}
+		http.NotFound(w, r)
+	})
+
+	// static stuff
+	static, err := control.disStatic()
+	if err != nil {
+		return nil, err
+	}
+	mux.Handle("/dis/static/", static)
+
+	// render everything
+	mux.Handle("/dis/index", httpx.HTMLHandler[disIndex]{
+		Handler:  control.disIndex,
+		Template: indexTemplate,
+	})
+
+	mux.Handle("/dis/instance/", httpx.HTMLHandler[disInstance]{
+		Handler:  control.disInstance,
+		Template: instanceTemplate,
+	})
+
+	// api -- for future usage
+	mux.Handle("/dis/api/v1/instance/get/", httpx.JSON(control.getinstance))
+	mux.Handle("/dis/api/v1/instance/all", httpx.JSON(control.allinstances))
+
+	// ensure that everyone is logged in!
+	return httpx.BasicAuth(mux, "WissKI Distillery Admin", func(user, pass string) bool {
+		return user == control.Config.DisAdminUser && pass == control.Config.DisAdminPassword
+	}), nil
+}
+
+// disIndex is the context of the "/dis/index" page
+type disIndex struct {
+	Time time.Time
+
+	Config *config.Config
+
+	Instances    []instances.Info
+	TotalCount   int
+	RunningCount int
+	StoppedCount int
+}
+
+func (dis *Control) disIndex(r *http.Request) (idx disIndex, err error) {
+	// load instances
+	idx.Instances, err = dis.allinstances(r)
+	if err != nil {
+		return
+	}
+
+	// count how many are running and how many are stopped
+	for _, i := range idx.Instances {
+		if i.Running {
+			idx.RunningCount++
+		} else {
+			idx.StoppedCount++
+		}
+	}
+	idx.TotalCount = len(idx.Instances)
+
+	// get the static properties
+	idx.Config = dis.Config
+
+	// current time
+	idx.Time = time.Now()
+
+	return
+}
+
+// disInstance is the context of the "/dis/instance/*" page
+type disInstance struct {
+	Time time.Time
+
+	Instance bookkeeping.Instance
+	Info     instances.Info
+}
+
+func (dis *Control) disInstance(r *http.Request) (is disInstance, err error) {
+	// find the slug as the last component of path!
+	slug := strings.TrimSuffix(r.URL.Path, "/")
+	slug = slug[strings.LastIndex(slug, "/")+1:]
+
+	// find the instance itself!
+	instance, err := dis.Instances.WissKI(slug)
+	if err == instances.ErrWissKINotFound {
+		return is, httpx.ErrNotFound
+	}
+	if err != nil {
+		return is, err
+	}
+	is.Instance = instance.Instance
+
+	// get some more info about the wisski
+	is.Info, err = instance.Info(false)
+	if err != nil {
+		return is, err
+	}
+
+	// current time
+	is.Time = time.Now()
+
+	return
+}
+
+//go:embed html/static
+var htmlStaticFS embed.FS
+
+func (*Control) disStatic() (http.Handler, error) {
+	fs, err := fs.Sub(htmlStaticFS, "html/static")
+	if err != nil {
+		return nil, err
+	}
+
+	return http.StripPrefix("/dis/static/", http.FileServer(http.FS(fs))), nil
+}
+
+//go:embed "html/index.html"
+var indexTemplateStr string
+var indexTemplate = template.Must(template.New("index.html").Parse(indexTemplateStr))
+
+//go:embed "html/instance.html"
+var instanceTemplateString string
+var instanceTemplate = template.Must(template.New("instance.html").Parse(instanceTemplateString))
+
+func (dis *Control) getinstance(r *http.Request) (info instances.Info, err error) {
+	// find the slug as the last component of path!
+	slug := strings.TrimSuffix(r.URL.Path, "/")
+	slug = slug[strings.LastIndex(slug, "/")+1:]
+
+	// load the wisski instance!
+	wisski, err := dis.Instances.WissKI(strings.TrimSuffix(slug, "/"))
+	if err == instances.ErrWissKINotFound {
+		return info, httpx.ErrNotFound
+	}
+	if err != nil {
+		return info, err
+	}
+
+	// get info about it!
+	return wisski.Info(false)
+}
+
+func (dis *Control) allinstances(*http.Request) (infos []instances.Info, err error) {
+	var errgroup errgroup.Group
+
+	// list all the instances
+	all, err := dis.Instances.All()
+	if err != nil {
+		return nil, err
+	}
+
+	// get all of their info!
+	infos = make([]instances.Info, len(all))
+	for i, instance := range all {
+		{
+			i := i
+			instance := instance
+
+			errgroup.Go(func() (err error) {
+				infos[i], err = instance.Info(true)
+				return err
+			})
+		}
+	}
+
+	// wait for the results, and return
+	err = errgroup.Wait()
+	return
+}

internal/component/control/resolver.go

@@ -0,0 +1,61 @@
+package control
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"regexp"
+
+	"github.com/FAU-CDI/wdresolve"
+	"github.com/FAU-CDI/wdresolve/resolvers"
+	"github.com/tkw1536/goprogram/stream"
+)
+
+func (control Control) ResolverConfigPath() string {
+	return filepath.Join(control.Dir, control.ResolverFile)
+}
+
+func (control Control) resolver(io stream.IOStream) (p wdresolve.ResolveHandler, err error) {
+	p.TrustXForwardedProto = true
+
+	fallback := &resolvers.Regexp{
+		Data: map[string]string{},
+	}
+
+	// handle the default domain name!
+	domainName := control.Config.DefaultDomain
+	if domainName != "" {
+		fallback.Data[fmt.Sprintf("^https?://(.*)\\.%s", regexp.QuoteMeta(domainName))] = fmt.Sprintf("https://$1.%s", domainName)
+		io.Printf("registering default domain %s\n", domainName)
+	}
+
+	// handle the extra domains!
+	for _, domain := range control.Config.SelfExtraDomains {
+		fallback.Data[fmt.Sprintf("^https?://(.*)\\.%s", regexp.QuoteMeta(domain))] = fmt.Sprintf("https://$1.%s", domainName)
+		io.Printf("registering legacy domain %s\n", domain)
+	}
+
+	// open the prefix file
+	prefixFile := control.ResolverConfigPath()
+	fs, err := os.Open(prefixFile)
+	io.Println("loading prefixes from ", prefixFile)
+	if err != nil {
+		return p, err
+	}
+	defer fs.Close()
+
+	// read the prefixes
+	// TODO: Do we want to load these without a file?
+	prefixes, err := resolvers.ReadPrefixes(fs)
+	if err != nil {
+		return p, err
+	}
+
+	// and use that as the resolver!
+	p.Resolver = resolvers.InOrder{
+		prefixes,
+		fallback,
+	}
+
+	return p, nil
+}

internal/component/control/self.go

@@ -0,0 +1,134 @@
+package control
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"os"
+	"strings"
+
+	"github.com/tkw1536/goprogram/stream"
+)
+
+// self returns the handler for the self overrides
+func (control Control) self(io stream.IOStream) (redirect Redirect, err error) {
+	// open the overrides file
+	overrides, err := os.Open(control.Config.SelfOverridesFile)
+	io.Printf("loading overrides from %q\n", control.Config.SelfOverridesFile)
+	if err != nil {
+		return redirect, err
+	}
+	defer overrides.Close()
+
+	// decode the overrides file
+	if err := json.NewDecoder(overrides).Decode(&redirect.Overrides); err != nil {
+		return redirect, err
+	}
+
+	if redirect.Overrides == nil {
+		redirect.Overrides = make(map[string]string)
+	}
+	redirect.Overrides[""] = control.Config.SelfRedirect.String()
+
+	// create a redirect server
+	redirect.Fallback, err = control.selfFallback()
+	if err != nil {
+		return redirect, err
+	}
+	redirect.Absolute = false
+	redirect.Permanent = false
+
+	// and return!
+	return redirect, nil
+}
+
+func (control *Control) selfFallback() (http.Handler, error) {
+	return http.HandlerFunc(control.serveFallback), nil
+}
+
+var notFoundText = []byte("not found")
+
+func (control *Control) serveFallback(w http.ResponseWriter, r *http.Request) {
+
+	slug := control.Config.SlugFromHost(r.Host)
+	if slug == "" {
+		w.WriteHeader(http.StatusNotFound)
+		w.Write(notFoundText)
+		return
+	}
+
+	if ok, _ := control.Instances.Has(slug); !ok {
+		w.WriteHeader(http.StatusNotFound)
+		fmt.Fprintf(w, "WissKI %q not found\n", slug)
+		return
+	}
+
+	w.WriteHeader(http.StatusBadGateway)
+	fmt.Fprintf(w, "WissKI %q is currently offline\n", slug)
+
+}
+
+// Redirect implements a redirect server that redirects all requests.
+// It implements http.Handler.
+type Redirect struct {
+	// Target is the target URL to redirect to.
+	Target string
+
+	// Fallback is used when target is the empty string.
+	Fallback http.Handler
+
+	// Absolute determines if the request path should be appended to the target URL when redirecting.
+	// By default this path is always appended, set Absolute to true to prevent this.
+	Absolute bool
+
+	// Overrides is a map from paths to URLs that should override the default target.
+	Overrides map[string]string
+
+	// Permanent determines if the redirect responses issued should return
+	// Permanent Redirect (Status Code 308) or Temporary Redirect (Status Code 307).
+	Permanent bool
+}
+
+// Redirect determines the redirect URL for a specific incoming request
+// If it returns the empty string, the fallback is used.
+func (redirect Redirect) Redirect(r *http.Request) string {
+	// if we have an override for this URL, use it immediatly
+	url := strings.TrimSuffix(r.URL.Path, "/")
+	if override, ok := redirect.Overrides[url]; ok {
+		return override
+	}
+
+	if redirect.Target == "" {
+		return ""
+	}
+
+	// if we are in absolute redirect mode, always return the absolute URL
+	if redirect.Absolute {
+		return redirect.Target
+	}
+
+	// return the target + the redirected URL
+	dest := strings.TrimSuffix(redirect.Target, "/") + r.URL.Path
+	if len(r.URL.RawQuery) > 0 {
+		dest += "?" + r.URL.RawQuery
+	}
+	return dest
+}
+
+// ServeHTTP implements the http.Handler interface and redirects a single request to redirect.Target.
+func (redirect Redirect) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	dest := redirect.Redirect(r)
+	if dest == "" {
+		redirect.Fallback.ServeHTTP(w, r)
+		return
+	}
+
+	// determine if we are temporary or permanent redirect
+	status := http.StatusTemporaryRedirect
+	if redirect.Permanent {
+		status = http.StatusPermanentRedirect
+	}
+
+	// and do the redirect
+	http.Redirect(w, r, dest, status)
+}

internal/component/control/server.go

@@ -0,0 +1,39 @@
+package control
+
+import (
+	"net/http"
+
+	"github.com/tkw1536/goprogram/stream"
+)
+
+// Server returns an http.Mux that implements the main server instance
+func (control Control) Server(io stream.IOStream) (http.Handler, error) {
+	// self server
+	self, err := control.self(io)
+	if err != nil {
+		return nil, err
+	}
+
+	resolver, err := control.resolver(io)
+	if err != nil {
+		return nil, err
+	}
+
+	info, err := control.info(io)
+	if err != nil {
+		return nil, err
+	}
+
+	// resolver
+
+	mux := http.NewServeMux()
+	mux.Handle("/", self)
+
+	mux.Handle("/go/", resolver)
+	mux.Handle("/wisski/get/", resolver)
+
+	// TODO: Fix me!
+	mux.Handle("/dis/", info)
+
+	return mux, nil
+}