feat: add short IDs + link shortener

backend/db/member.go

@@ -3,8 +3,10 @@ package db
 import (
 	"context"
 	"regexp"
+	"time"
 
 	"emperror.dev/errors"
+	"github.com/Masterminds/squirrel"
 	"github.com/georgysavva/scany/v2/pgxscan"
 	"github.com/jackc/pgx/v5"
 	"github.com/jackc/pgx/v5/pgconn"
@@ -19,6 +21,7 @@ const (
 type Member struct {
 	ID          xid.ID
 	UserID      xid.ID
+	SID         string `db:"sid"`
 	Name        string
 	DisplayName *string
 	Bio         *string
@@ -73,6 +76,25 @@ func (db *DB) UserMember(ctx context.Context, userID xid.ID, memberRef string) (
 	return m, nil
 }
 
+// MemberBySID gets a user by their short ID.
+func (db *DB) MemberBySID(ctx context.Context, sid string) (u Member, err error) {
+	sql, args, err := sq.Select("*").From("members").Where("sid = ?", sid).ToSql()
+	if err != nil {
+		return u, errors.Wrap(err, "building sql")
+	}
+
+	err = pgxscan.Get(ctx, db, &u, sql, args...)
+	if err != nil {
+		if errors.Cause(err) == pgx.ErrNoRows {
+			return u, ErrMemberNotFound
+		}
+
+		return u, errors.Wrap(err, "getting members from db")
+	}
+
+	return u, nil
+}
+
 // UserMembers returns all of a user's members, sorted by name.
 func (db *DB) UserMembers(ctx context.Context, userID xid.ID, showHidden bool) (ms []Member, err error) {
 	builder := sq.Select("*").
@@ -104,8 +126,8 @@ func (db *DB) CreateMember(
 	name string, displayName *string, bio string, links []string,
 ) (m Member, err error) {
 	sql, args, err := sq.Insert("members").
-		Columns("user_id", "id", "name", "display_name", "bio", "links").
+		Columns("user_id", "id", "sid", "name", "display_name", "bio", "links").
-		Values(userID, xid.New(), name, displayName, bio, links).
+		Values(userID, xid.New(), squirrel.Expr("find_free_member_sid()"), name, displayName, bio, links).
 		Suffix("RETURNING *").ToSql()
 	if err != nil {
 		return m, errors.Wrap(err, "building sql")
@@ -232,3 +254,43 @@ func (db *DB) UpdateMember(
 	}
 	return m, nil
 }
+
+func (db *DB) RerollMemberSID(ctx context.Context, userID, memberID xid.ID) (newID string, err error) {
+	tx, err := db.Begin(ctx)
+	if err != nil {
+		return "", errors.Wrap(err, "beginning transaction")
+	}
+	defer tx.Rollback(ctx)
+
+	sql, args, err := sq.Update("members").
+		Set("sid", squirrel.Expr("find_free_member_sid()")).
+		Where("id = ?", memberID).
+		Suffix("RETURNING sid").ToSql()
+	if err != nil {
+		return "", errors.Wrap(err, "building sql")
+	}
+
+	err = tx.QueryRow(ctx, sql, args...).Scan(&newID)
+	if err != nil {
+		return "", errors.Wrap(err, "executing query")
+	}
+
+	sql, args, err = sq.Update("users").
+		Set("last_sid_reroll", time.Now()).
+		Where("id = ?", userID).ToSql()
+	if err != nil {
+		return "", errors.Wrap(err, "building sql")
+	}
+
+	_, err = tx.Exec(ctx, sql, args...)
+	if err != nil {
+		return "", errors.Wrap(err, "executing query")
+	}
+
+	err = tx.Commit(ctx)
+	if err != nil {
+		return "", errors.Wrap(err, "committing transaction")
+	}
+
+	return newID, nil
+}

backend/db/user.go

@@ -11,6 +11,7 @@ import (
 	"codeberg.org/u1f320/pronouns.cc/backend/common"
 	"codeberg.org/u1f320/pronouns.cc/backend/icons"
 	"emperror.dev/errors"
+	"github.com/Masterminds/squirrel"
 	"github.com/bwmarrin/discordgo"
 	"github.com/georgysavva/scany/v2/pgxscan"
 	"github.com/jackc/pgx/v5"
@@ -20,6 +21,7 @@ import (
 
 type User struct {
 	ID          xid.ID
+	SID         string `db:"sid"`
 	Username    string
 	DisplayName *string
 	Bio         *string
@@ -49,6 +51,7 @@ type User struct {
 	MaxInvites    int
 	IsAdmin       bool
 	ListPrivate   bool
+	LastSIDReroll time.Time `db:"last_sid_reroll"`
 
 	DeletedAt    *time.Time
 	SelfDelete   *bool
@@ -161,7 +164,7 @@ func (db *DB) CreateUser(ctx context.Context, tx pgx.Tx, username string) (u Use
 		return u, err
 	}
 
-	sql, args, err := sq.Insert("users").Columns("id", "username").Values(xid.New(), username).Suffix("RETURNING *").ToSql()
+	sql, args, err := sq.Insert("users").Columns("id", "username", "sid").Values(xid.New(), username, squirrel.Expr("find_free_user_sid()")).Suffix("RETURNING *").ToSql()
 	if err != nil {
 		return u, errors.Wrap(err, "building sql")
 	}
@@ -468,6 +471,25 @@ func (db *DB) Username(ctx context.Context, name string) (u User, err error) {
 	return u, nil
 }
 
+// UserBySID gets a user by their short ID.
+func (db *DB) UserBySID(ctx context.Context, sid string) (u User, err error) {
+	sql, args, err := sq.Select("*").From("users").Where("sid = ?", sid).ToSql()
+	if err != nil {
+		return u, errors.Wrap(err, "building sql")
+	}
+
+	err = pgxscan.Get(ctx, db, &u, sql, args...)
+	if err != nil {
+		if errors.Cause(err) == pgx.ErrNoRows {
+			return u, ErrUserNotFound
+		}
+
+		return u, errors.Wrap(err, "getting user from db")
+	}
+
+	return u, nil
+}
+
 // UsernameTaken checks if the given username is already taken.
 func (db *DB) UsernameTaken(ctx context.Context, username string) (valid, taken bool, err error) {
 	if err := UsernameValid(username); err != nil {
@@ -596,6 +618,23 @@ func (db *DB) DeleteUser(ctx context.Context, tx pgx.Tx, id xid.ID, selfDelete b
 	return nil
 }
 
+func (db *DB) RerollUserSID(ctx context.Context, id xid.ID) (newID string, err error) {
+	sql, args, err := sq.Update("users").
+		Set("sid", squirrel.Expr("find_free_user_sid()")).
+		Set("last_sid_reroll", time.Now()).
+		Where("id = ?", id).
+		Suffix("RETURNING sid").ToSql()
+	if err != nil {
+		return "", errors.Wrap(err, "building sql")
+	}
+
+	err = db.QueryRow(ctx, sql, args...).Scan(&newID)
+	if err != nil {
+		return "", errors.Wrap(err, "executing query")
+	}
+	return newID, nil
+}
+
 func (db *DB) UndoDeleteUser(ctx context.Context, id xid.ID) error {
 	sql, args, err := sq.Update("users").
 		Set("deleted_at", nil).

backend/prns/main.go

@@ -0,0 +1,99 @@
+package prns
+
+import (
+	"context"
+	"net/http"
+	"os"
+	"os/signal"
+	"strings"
+
+	dbpkg "codeberg.org/u1f320/pronouns.cc/backend/db"
+	"codeberg.org/u1f320/pronouns.cc/backend/log"
+	"github.com/urfave/cli/v2"
+)
+
+var Command = &cli.Command{
+	Name:   "shortener",
+	Usage:  "URL shortener service",
+	Action: run,
+}
+
+func run(c *cli.Context) error {
+	port := ":" + os.Getenv("PRNS_PORT")
+	baseURL := os.Getenv("BASE_URL")
+
+	db, err := dbpkg.New()
+	if err != nil {
+		log.Fatalf("creating database: %v", err)
+		return err
+	}
+
+	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+		defer func() {
+			if r := recover(); r != nil {
+				log.Errorf("recovered from panic: %v", err)
+			}
+		}()
+
+		id := strings.TrimPrefix(r.URL.Path, "/")
+		if len(id) == 5 {
+			u, err := db.UserBySID(r.Context(), id)
+			if err != nil {
+				if err != dbpkg.ErrUserNotFound {
+					log.Errorf("getting user: %v", err)
+				}
+
+				http.Redirect(w, r, baseURL, http.StatusTemporaryRedirect)
+				return
+			}
+			http.Redirect(w, r, baseURL+"/@"+u.Username, http.StatusTemporaryRedirect)
+			return
+		}
+
+		if len(id) == 6 {
+			m, err := db.MemberBySID(r.Context(), id)
+			if err != nil {
+				if err != dbpkg.ErrMemberNotFound {
+					log.Errorf("getting member: %v", err)
+				}
+
+				http.Redirect(w, r, baseURL, http.StatusTemporaryRedirect)
+				return
+			}
+
+			u, err := db.User(r.Context(), m.UserID)
+			if err != nil {
+				log.Errorf("getting user for member %v: %v", m.ID, err)
+
+				http.Redirect(w, r, baseURL, http.StatusTemporaryRedirect)
+				return
+			}
+
+			http.Redirect(w, r, baseURL+"/@"+u.Username+"/"+m.Name, http.StatusTemporaryRedirect)
+			return
+		}
+
+		http.Redirect(w, r, baseURL, http.StatusTemporaryRedirect)
+	})
+
+	e := make(chan error)
+	go func() {
+		e <- http.ListenAndServe(port, nil)
+	}()
+
+	ctx, stop := signal.NotifyContext(context.Background(), os.Interrupt)
+	defer stop()
+
+	log.Infof("API server running at %v!", port)
+
+	select {
+	case <-ctx.Done():
+		log.Info("Interrupt signal received, shutting down...")
+		db.Close()
+		return nil
+	case err := <-e:
+		log.Fatalf("Error running server: %v", err)
+	}
+
+	return nil
+}

backend/routes/member/get_member.go

@@ -14,6 +14,7 @@ import (
 
 type GetMemberResponse struct {
 	ID          xid.ID   `json:"id"`
+	SID         string   `json:"sid"`
 	Name        string   `json:"name"`
 	DisplayName *string  `json:"display_name"`
 	Bio         *string  `json:"bio"`
@@ -33,6 +34,7 @@ type GetMemberResponse struct {
 func dbMemberToMember(u db.User, m db.Member, fields []db.Field, flags []db.MemberFlag, isOwnMember bool) GetMemberResponse {
 	r := GetMemberResponse{
 		ID:          m.ID,
+		SID:         m.SID,
 		Name:        m.Name,
 		DisplayName: m.DisplayName,
 		Bio:         m.Bio,

backend/routes/member/get_members.go

@@ -12,6 +12,7 @@ import (
 
 type memberListResponse struct {
 	ID          xid.ID            `json:"id"`
+	SID         string            `json:"sid"`
 	Name        string            `json:"name"`
 	DisplayName *string           `json:"display_name"`
 	Bio         *string           `json:"bio"`
@@ -27,6 +28,7 @@ func membersToMemberList(ms []db.Member, isSelf bool) []memberListResponse {
 	for i := range ms {
 		resps[i] = memberListResponse{
 			ID:          ms[i].ID,
+			SID:         ms[i].SID,
 			Name:        ms[i].Name,
 			DisplayName: ms[i].DisplayName,
 			Bio:         ms[i].Bio,

backend/routes/member/patch_member.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"net/http"
 	"strings"
+	"time"
 
 	"codeberg.org/u1f320/pronouns.cc/backend/common"
 	"codeberg.org/u1f320/pronouns.cc/backend/db"
@@ -319,3 +320,49 @@ func (s *Server) patchMember(w http.ResponseWriter, r *http.Request) error {
 	render.JSON(w, r, dbMemberToMember(u, m, fields, flags, true))
 	return nil
 }
+
+func (s *Server) rerollMemberSID(w http.ResponseWriter, r *http.Request) error {
+	ctx := r.Context()
+
+	claims, _ := server.ClaimsFromContext(ctx)
+
+	if !claims.TokenWrite {
+		return server.APIError{Code: server.ErrMissingPermissions, Details: "This token is read-only"}
+	}
+
+	id, err := xid.FromString(chi.URLParam(r, "memberRef"))
+	if err != nil {
+		return server.APIError{Code: server.ErrMemberNotFound}
+	}
+
+	u, err := s.DB.User(ctx, claims.UserID)
+	if err != nil {
+		return errors.Wrap(err, "getting user")
+	}
+
+	m, err := s.DB.Member(ctx, id)
+	if err != nil {
+		if err == db.ErrMemberNotFound {
+			return server.APIError{Code: server.ErrMemberNotFound}
+		}
+
+		return errors.Wrap(err, "getting member")
+	}
+
+	if m.UserID != claims.UserID {
+		return server.APIError{Code: server.ErrNotOwnMember}
+	}
+
+	if time.Now().Add(-time.Hour).Before(u.LastSIDReroll) {
+		return server.APIError{Code: server.ErrRerollingTooQuickly}
+	}
+
+	newID, err := s.DB.RerollMemberSID(ctx, u.ID, m.ID)
+	if err != nil {
+		return errors.Wrap(err, "updating member SID")
+	}
+
+	m.SID = newID
+	render.JSON(w, r, dbMemberToMember(u, m, nil, nil, true))
+	return nil
+}

backend/routes/member/routes.go

@@ -29,5 +29,8 @@ func Mount(srv *server.Server, r chi.Router) {
 		r.With(server.MustAuth).Post("/", server.WrapHandler(s.createMember))
 		r.With(server.MustAuth).Patch("/{memberRef}", server.WrapHandler(s.patchMember))
 		r.With(server.MustAuth).Delete("/{memberRef}", server.WrapHandler(s.deleteMember))
+
+		// reroll member SID
+		r.With(server.MustAuth).Get("/{memberRef}/reroll", server.WrapHandler(s.rerollMemberSID))
 	})
 }

backend/routes/user/get_user.go

@@ -14,6 +14,7 @@ import (
 
 type GetUserResponse struct {
 	ID                xid.ID               `json:"id"`
+	SID               string               `json:"sid"`
 	Username          string               `json:"name"`
 	DisplayName       *string              `json:"display_name"`
 	Bio               *string              `json:"bio"`
@@ -36,6 +37,7 @@ type GetMeResponse struct {
 	MaxInvites    int       `json:"max_invites"`
 	IsAdmin       bool      `json:"is_admin"`
 	ListPrivate   bool      `json:"list_private"`
+	LastSIDReroll time.Time `json:"last_sid_reroll"`
 
 	Discord         *string `json:"discord"`
 	DiscordUsername *string `json:"discord_username"`
@@ -53,6 +55,7 @@ type GetMeResponse struct {
 
 type PartialMember struct {
 	ID          xid.ID            `json:"id"`
+	SID         string            `json:"sid"`
 	Name        string            `json:"name"`
 	DisplayName *string           `json:"display_name"`
 	Bio         *string           `json:"bio"`
@@ -65,6 +68,7 @@ type PartialMember struct {
 func dbUserToResponse(u db.User, fields []db.Field, members []db.Member, flags []db.UserFlag) GetUserResponse {
 	resp := GetUserResponse{
 		ID:                u.ID,
+		SID:               u.SID,
 		Username:          u.Username,
 		DisplayName:       u.DisplayName,
 		Bio:               u.Bio,
@@ -82,6 +86,7 @@ func dbUserToResponse(u db.User, fields []db.Field, members []db.Member, flags [
 	for i := range members {
 		resp.Members[i] = PartialMember{
 			ID:          members[i].ID,
+			SID:         members[i].SID,
 			Name:        members[i].Name,
 			DisplayName: members[i].DisplayName,
 			Bio:         members[i].Bio,
@@ -188,6 +193,7 @@ func (s *Server) getMeUser(w http.ResponseWriter, r *http.Request) error {
 		MaxInvites:        u.MaxInvites,
 		IsAdmin:           u.IsAdmin,
 		ListPrivate:       u.ListPrivate,
+		LastSIDReroll:     u.LastSIDReroll,
 		Discord:           u.Discord,
 		DiscordUsername:   u.DiscordUsername,
 		Tumblr:            u.Tumblr,

backend/routes/user/patch_user.go

@@ -3,6 +3,7 @@ package user
 import (
 	"fmt"
 	"net/http"
+	"time"
 
 	"codeberg.org/u1f320/pronouns.cc/backend/common"
 	"codeberg.org/u1f320/pronouns.cc/backend/db"
@@ -313,6 +314,7 @@ func (s *Server) patchUser(w http.ResponseWriter, r *http.Request) error {
 		MaxInvites:        u.MaxInvites,
 		IsAdmin:           u.IsAdmin,
 		ListPrivate:       u.ListPrivate,
+		LastSIDReroll:     u.LastSIDReroll,
 		Discord:           u.Discord,
 		DiscordUsername:   u.DiscordUsername,
 		Tumblr:            u.Tumblr,
@@ -362,3 +364,31 @@ func validateSlicePtr[T validator](typ string, slice *[]T, custom db.CustomPrefe
 
 	return nil
 }
+
+func (s *Server) rerollUserSID(w http.ResponseWriter, r *http.Request) error {
+	ctx := r.Context()
+
+	claims, _ := server.ClaimsFromContext(ctx)
+
+	if !claims.TokenWrite {
+		return server.APIError{Code: server.ErrMissingPermissions, Details: "This token is read-only"}
+	}
+
+	u, err := s.DB.User(ctx, claims.UserID)
+	if err != nil {
+		return errors.Wrap(err, "getting existing user")
+	}
+
+	if time.Now().Add(-time.Hour).Before(u.LastSIDReroll) {
+		return server.APIError{Code: server.ErrRerollingTooQuickly}
+	}
+
+	newID, err := s.DB.RerollUserSID(ctx, u.ID)
+	if err != nil {
+		return errors.Wrap(err, "updating user SID")
+	}
+
+	u.SID = newID
+	render.JSON(w, r, dbUserToResponse(u, nil, nil, nil))
+	return nil
+}

backend/routes/user/routes.go

@@ -34,6 +34,8 @@ func Mount(srv *server.Server, r chi.Router) {
 			r.Post("/@me/flags", server.WrapHandler(s.postUserFlag))
 			r.Patch("/@me/flags/{flagID}", server.WrapHandler(s.patchUserFlag))
 			r.Delete("/@me/flags/{flagID}", server.WrapHandler(s.deleteUserFlag))
+
+			r.Get("/@me/reroll", server.WrapHandler(s.rerollUserSID))
 		})
 	})
 }

backend/server/errors.go

@@ -103,6 +103,7 @@ const (
 	ErrUserNotFound        = 2001
 	ErrMemberListPrivate   = 2002
 	ErrFlagLimitReached    = 2003
+	ErrRerollingTooQuickly = 2004
 
 	// Member-related error codes
 	ErrMemberNotFound     = 3001
@@ -148,6 +149,7 @@ var errCodeMessages = map[int]string{
 	ErrUserNotFound:        "User not found",
 	ErrMemberListPrivate:   "This user's member list is private",
 	ErrFlagLimitReached:    "Maximum number of pride flags reached",
+	ErrRerollingTooQuickly: "You can only reroll one short ID per hour.",
 
 	ErrMemberNotFound:     "Member not found",
 	ErrMemberLimitReached: "Member limit reached",
@@ -190,6 +192,7 @@ var errCodeStatuses = map[int]int{
 	ErrUserNotFound:        http.StatusNotFound,
 	ErrMemberListPrivate:   http.StatusForbidden,
 	ErrFlagLimitReached:    http.StatusBadRequest,
+	ErrRerollingTooQuickly: http.StatusForbidden,
 
 	ErrMemberNotFound:     http.StatusNotFound,
 	ErrMemberLimitReached: http.StatusBadRequest,

frontend/src/lib/api/entities.ts

@@ -6,6 +6,7 @@ export const MAX_DESCRIPTION_LENGTH = 1000;
 
 export interface User {
   id: string;
+  sid: string;
   name: string;
   display_name: string | null;
   bio: string | null;
@@ -53,6 +54,7 @@ export interface MeUser extends User {
   fediverse_username: string | null;
   fediverse_instance: string | null;
   list_private: boolean;
+  last_sid_reroll: string;
 }
 
 export interface Field {
@@ -73,6 +75,7 @@ export interface Pronoun {
 
 export interface PartialMember {
   id: string;
+  sid: string;
   name: string;
   display_name: string | null;
   bio: string | null;

frontend/src/routes/@[username]/+page.svelte

@@ -30,6 +30,7 @@
     type Pronoun,
   } from "$lib/api/entities";
   import { PUBLIC_BASE_URL } from "$env/static/public";
+  import { env } from "$env/dynamic/public";
   import { apiFetchClient } from "$lib/api/fetch";
   import ErrorAlert from "$lib/components/ErrorAlert.svelte";
   import { goto } from "$app/navigation";
@@ -41,6 +42,7 @@
   import defaultPreferences from "$lib/api/default_preferences";
   import { addToast } from "$lib/toast";
   import ProfileFlag from "./ProfileFlag.svelte";
+  import IconButton from "$lib/components/IconButton.svelte";
 
   export let data: PageData;
 
@@ -117,6 +119,12 @@
     addToast({ body: "Copied the link to your clipboard!", duration: 2000 });
   };
 
+  const copyShortURL = async () => {
+    const url = `${env.PUBLIC_SHORT_BASE}/${data.sid}`;
+    await navigator.clipboard.writeText(url);
+    addToast({ body: "Copied the short link to your clipboard!", duration: 2000 });
+  };
+
   onMount(async () => {
     if ($userStore && $userStore.id === data.id) {
       console.log("User is current user, fetching members");
@@ -231,6 +239,15 @@
           <Button color="secondary" outline on:click={copyURL}>
             <Icon name="clipboard" /> Copy link
           </Button>
+          {#if env.PUBLIC_SHORT_BASE}
+            <IconButton
+              outline
+              icon="link-45deg"
+              tooltip="Copy short link"
+              color="secondary"
+              click={copyShortURL}
+            />
+          {/if}
           {#if $userStore && $userStore.id !== data.id}
             <ReportButton subject="user" reportUrl="/users/{data.id}/reports" />
           {/if}

frontend/src/routes/@[username]/[memberName]/+page.svelte

@@ -13,6 +13,7 @@
     type Pronoun,
   } from "$lib/api/entities";
   import { PUBLIC_BASE_URL } from "$env/static/public";
+  import { env } from "$env/dynamic/public";
   import { userStore } from "$lib/store";
   import { renderMarkdown } from "$lib/utils";
   import ReportButton from "../ReportButton.svelte";
@@ -21,6 +22,7 @@
   import defaultPreferences from "$lib/api/default_preferences";
   import { addToast } from "$lib/toast";
   import ProfileFlag from "../ProfileFlag.svelte";
+  import IconButton from "$lib/components/IconButton.svelte";
 
   export let data: PageData;
 
@@ -51,6 +53,12 @@
     await navigator.clipboard.writeText(url);
     addToast({ body: "Copied the link to your clipboard!", duration: 2000 });
   };
+
+  const copyShortURL = async () => {
+    const url = `${env.PUBLIC_SHORT_BASE}/${data.sid}`;
+    await navigator.clipboard.writeText(url);
+    addToast({ body: "Copied the short link to your clipboard!", duration: 2000 });
+  };
 </script>
 
 <div class="container">
@@ -153,6 +161,15 @@
           <Button color="secondary" outline on:click={copyURL}>
             <Icon name="clipboard" /> Copy link
           </Button>
+          {#if env.PUBLIC_SHORT_BASE}
+            <IconButton
+              outline
+              icon="link-45deg"
+              tooltip="Copy short link"
+              color="secondary"
+              click={copyShortURL}
+            />
+          {/if}
           {#if $userStore && $userStore.id !== data.user.id}
             <ReportButton subject="member" reportUrl="/members/{data.id}/reports" />
           {/if}

frontend/src/routes/edit/member/[id]/+page.svelte

@@ -28,8 +28,10 @@
     CardHeader,
     Alert,
   } from "sveltestrap";
+  import { DateTime } from "luxon";
   import { encode } from "base64-arraybuffer";
   import prettyBytes from "pretty-bytes";
+  import { env } from "$env/dynamic/public";
   import { apiFetchClient, fastFetchClient } from "$lib/api/fetch";
   import IconButton from "$lib/components/IconButton.svelte";
   import EditableField from "../../EditableField.svelte";
@@ -373,6 +375,28 @@
   let deleteName = "";
   let deleteError: APIError | null = null;
 
+  const now = DateTime.now().toLocal();
+  let canRerollSid: boolean;
+  $: canRerollSid =
+    now.diff(DateTime.fromISO(data.user.last_sid_reroll).toLocal(), "hours").hours >= 1;
+
+  const rerollSid = async () => {
+    try {
+      const resp = await apiFetchClient<Member>(`/members/${data.member.id}/reroll`);
+      addToast({ header: "Success", body: "Rerolled short ID!" });
+      error = null;
+      data.member.sid = resp.sid;
+    } catch (e) {
+      error = e as APIError;
+    }
+  };
+
+  const copyShortURL = async () => {
+    const url = `${env.PUBLIC_SHORT_BASE}/${data.member.sid}`;
+    await navigator.clipboard.writeText(url);
+    addToast({ body: "Copied the short link to your clipboard!", duration: 2000 });
+  };
+
   interface SnapshotData {
     bio: string;
     name: string;
@@ -407,19 +431,19 @@
       newLink,
     }),
     restore: (value) => {
-      bio = value.bio
+      bio = value.bio;
-      name = value.name
+      name = value.name;
-      display_name = value.display_name
+      display_name = value.display_name;
-      links = value.links
+      links = value.links;
-      names = value.names
+      names = value.names;
-      pronouns = value.pronouns
+      pronouns = value.pronouns;
-      fields = value.fields
+      fields = value.fields;
-      flags = value.flags
+      flags = value.flags;
-      unlisted = value.unlisted
+      unlisted = value.unlisted;
-      avatar = value.avatar
+      avatar = value.avatar;
-      newName = value.newName
+      newName = value.newName;
-      newPronouns = value.newPronouns
+      newPronouns = value.newPronouns;
-      newLink = value.newLink
+      newLink = value.newLink;
     },
   };
 </script>
@@ -755,6 +779,30 @@
           </strong>
         </p>
       </div>
+      {#if env.PUBLIC_SHORT_BASE}
+        <div class="col-md">
+          <p>
+            Current short ID: <code>{data.member.sid}</code>
+            <ButtonGroup class="mb-1">
+              <Button color="secondary" disabled={!canRerollSid} on:click={() => rerollSid()}
+                >Reroll short ID</Button
+              >
+              <IconButton
+                icon="link-45deg"
+                tooltip="Copy short link"
+                color="secondary"
+                click={copyShortURL}
+              />
+            </ButtonGroup>
+            <br />
+            <span class="text-muted">
+              <Icon name="info-circle-fill" aria-hidden />
+              This ID is used in <code>prns.cc</code> links. You can reroll one short ID every hour (shared
+              between your main profile and all members) by pressing the button above.
+            </span>
+          </p>
+        </div>
+      {/if}
     </div>
   </TabPane>
 </TabContent>

frontend/src/routes/edit/profile/+page.svelte

@@ -28,7 +28,9 @@
     TabPane,
   } from "sveltestrap";
   import { encode } from "base64-arraybuffer";
+  import { DateTime } from "luxon";
   import { apiFetchClient } from "$lib/api/fetch";
+  import { env } from "$env/dynamic/public";
   import IconButton from "$lib/components/IconButton.svelte";
   import EditableField from "../EditableField.svelte";
   import EditableName from "../EditableName.svelte";
@@ -379,6 +381,28 @@
     }
   };
 
+  const now = DateTime.now().toLocal();
+  let canRerollSid: boolean;
+  $: canRerollSid =
+    now.diff(DateTime.fromISO(data.user.last_sid_reroll).toLocal(), "hours").hours >= 1;
+
+  const rerollSid = async () => {
+    try {
+      const resp = await apiFetchClient<MeUser>("/users/@me/reroll");
+      addToast({ header: "Success", body: "Rerolled short ID!" });
+      error = null;
+      data.user.sid = resp.sid;
+    } catch (e) {
+      error = e as APIError;
+    }
+  };
+
+  const copyShortURL = async () => {
+    const url = `${env.PUBLIC_SHORT_BASE}/${data.user.sid}`;
+    await navigator.clipboard.writeText(url);
+    addToast({ body: "Copied the short link to your clipboard!", duration: 2000 });
+  };
+
   interface SnapshotData {
     bio: string;
     display_name: string;
@@ -721,6 +745,29 @@
             will be used.
           </p>
         </FormGroup>
+        {#if env.PUBLIC_SHORT_BASE}
+          <hr />
+          <p>
+            Current short ID: <code>{data.user.sid}</code>
+            <ButtonGroup class="mb-1">
+              <Button color="secondary" disabled={!canRerollSid} on:click={() => rerollSid()}
+                >Reroll short ID</Button
+              >
+              <IconButton
+                icon="link-45deg"
+                tooltip="Copy short link"
+                color="secondary"
+                click={copyShortURL}
+              />
+            </ButtonGroup>
+            <br />
+            <span class="text-muted">
+              <Icon name="info-circle-fill" aria-hidden />
+              This ID is used in <code>prns.cc</code> links. You can reroll one short ID every hour (shared
+              between your main profile and all members) by pressing the button above.
+            </span>
+          </p>
+        {/if}
       </div>
       <div class="col-md">
         <div class="form-check">

main.go

@@ -6,6 +6,7 @@ import (
 
 	"codeberg.org/u1f320/pronouns.cc/backend"
 	"codeberg.org/u1f320/pronouns.cc/backend/exporter"
+	"codeberg.org/u1f320/pronouns.cc/backend/prns"
 	"codeberg.org/u1f320/pronouns.cc/backend/server"
 	"codeberg.org/u1f320/pronouns.cc/scripts/cleandb"
 	"codeberg.org/u1f320/pronouns.cc/scripts/genid"
@@ -22,6 +23,7 @@ var app = &cli.App{
 	Commands: []*cli.Command{
 		backend.Command,
 		exporter.Command,
+		prns.Command,
 		{
 			Name:    "database",
 			Aliases: []string{"db"},

scripts/migrate/018_short_ids.sql

@@ -0,0 +1,50 @@
+-- +migrate Up
+
+-- 2023-06-03: Add short IDs for the prns.cc domain.
+
+-- add the columns
+alter table users add column sid text unique check(length(sid)=5);
+alter table members add column sid text unique check(length(sid)=6);
+alter table users add column last_sid_reroll timestamptz not null default now() - '1 hour'::interval;
+
+-- create the generate short ID functions
+-- these are copied from PluralKit's HID functions:
+-- https://github.com/PluralKit/PluralKit/blob/e4a2930bf353af9406e48934569677d7de6dd90d/PluralKit.Core/Database/Functions/functions.sql#L118-L152
+
+-- +migrate StatementBegin
+create function generate_sid(len int) returns text as $$
+    select string_agg(substr('abcdefghijklmnopqrstuvwxyz', ceil(random() * 26)::integer, 1), '') from generate_series(1, len)
+$$ language sql volatile;
+-- +migrate StatementEnd
+
+-- +migrate StatementBegin
+create function find_free_user_sid() returns text as $$
+declare new_sid text;
+begin
+    loop
+        new_sid := generate_sid(5);
+        if not exists (select 1 from users where sid = new_sid) then return new_sid; end if;
+    end loop;
+end
+$$ language plpgsql volatile;
+-- +migrate StatementEnd
+
+-- +migrate StatementBegin
+create function find_free_member_sid() returns text as $$
+declare new_sid text;
+begin
+    loop
+        new_sid := generate_sid(6);
+        if not exists (select 1 from members where sid = new_sid) then return new_sid; end if;
+    end loop;
+end
+$$ language plpgsql volatile;
+-- +migrate StatementEnd
+
+-- give all users and members short IDs
+update users set sid = find_free_user_sid();
+update members set sid = find_free_member_sid();
+
+-- finally, make the values non-nullable
+alter table users alter column sid set not null;
+alter table members alter column sid set not null;