Allow changing collection URL name

app/blueprints/collections/__init__.py

@@ -22,7 +22,7 @@ from flask_babel import lazy_gettext, gettext
 from flask_login import current_user, login_required
 from flask_wtf import FlaskForm
 from wtforms import StringField, BooleanField, SubmitField, FieldList, HiddenField
-from wtforms.validators import InputRequired, Length, Optional
+from wtforms.validators import InputRequired, Length, Optional, Regexp
 
 from app.models import Collection, db, Package, Permission, CollectionPackage, User, UserRank, AuditSeverity
 from app.utils import is_package_page, nonempty_or_none, add_audit_log
@@ -70,6 +70,8 @@ def view(author, name):
 
 class CollectionForm(FlaskForm):
 	title = StringField(lazy_gettext("Title"), [InputRequired(), Length(3, 100)])
+	name = StringField("URL", [Optional(), Length(1, 20), Regexp("^[a-z0-9_]", 0,
+		"Lower case letters (a-z), digits (0-9), and underscores (_) only")])
 	short_description = StringField(lazy_gettext("Short Description"), [Optional(), Length(0, 200)])
 	private = BooleanField(lazy_gettext("Private"))
 	descriptions = FieldList(
@@ -113,6 +115,8 @@ def create_edit(author=None, name=None):
 			for item in collection.items:
 				form.descriptions.append_entry(item.description)
 				form.package_ids.append_entry(item.package.id)
+		else:
+			form.name = None
 
 	if form.validate_on_submit():
 		ret = handle_create_edit(collection, form, initial_package, author)
@@ -127,9 +131,9 @@ def handle_create_edit(collection: Collection, form: CollectionForm,
 		initial_package: typing.Optional[Package], author: User):
 
 	severity = AuditSeverity.NORMAL if author == current_user else AuditSeverity.EDITOR
-	name = collection.name if collection else regex_invalid_chars.sub("", form.title.data.lower().replace(" ", "_"))
+	name = form.name.data if collection else regex_invalid_chars.sub("", form.title.data.lower().replace(" ", "_"))
 
-	if collection is None:
+	if collection is None or name != collection.name:
 		if Collection.query \
 				.filter(Collection.name == name, Collection.author == author) \
 				.count() > 0:
@@ -142,6 +146,7 @@ def handle_create_edit(collection: Collection, form: CollectionForm,
 			flash(gettext("Unable to create collection as a package with that name already exists"), "danger")
 			return
 
+	if collection is None:
 		collection = Collection()
 		collection.name = name
 		collection.author = author

app/templates/collections/create_edit.html

@@ -9,13 +9,22 @@
 {% endblock %}
 
 {% block content %}
-	{% from "macros/forms.html" import render_field, render_submit_field, render_checkbox_field %}
+	{% from "macros/forms.html" import render_field, render_submit_field, render_checkbox_field, render_field_prefix_button %}
 	<form method="POST" action="" enctype="multipart/form-data">
 		{{ render_submit_field(form.submit, class_="btn btn-primary float-right") }}
 		<h1>{{ self.title() }}</h1>
 
 		{{ form.hidden_tag() }}
-		{{ render_field(form.title) }}
+
+		<div class="row">
+			{{ render_field(form.title, class_="col-sm-6") }}
+			{% if form.name %}
+				{{ render_field_prefix_button(form.name, class_="col-sm-6", pattern="[a-z0-9_]+",
+					prefix="/collections/" + collection.author.username + "/",
+					hint=_("Users won't be redirected when going to the old URL")) }}
+			{% endif %}
+		</div>
+
 		{{ render_field(form.short_description) }}
 		{{ render_checkbox_field(form.private, class_="my-3") }}
 

app/templates/macros/forms.html

@@ -36,24 +36,29 @@
 	</div>
 {%- endmacro %}
 
-{% macro render_field_prefix_button(field, label=None, prefix="@", label_visible=true, right_url=None, right_label=None, fieldclass=None) -%}
+{% macro render_field_prefix_button(field, label=None, prefix="@", label_visible=true, right_url=None, right_label=None, fieldclass=None, has_view=False, hint=None) -%}
 	<div class="form-group {% if field.errors %}has-danger{% endif %} {{ kwargs.pop('class_', '') }}">
 		{% if field.type != 'HiddenField' and label_visible %}
 			{% if not label and label != "" %}{% set label=field.label.text %}{% endif %}
 			{% if label %}<label for="{{ field.id }}">{{ label|safe }}</label>{% endif %}
 		{% endif %}
 
-		<div class="input-group mb-3">
+		<div class="input-group mb-1">
 			<div class="input-group-prepend">
 				<span class="input-group-text" id="basic-addon1">{{ prefix }}</span>
 			</div>
 			{{ field(class_=fieldclass or 'form-control', **kwargs) }}
-			<a class="btn btn-secondary" id="{{ field.name }}-button">
-				{{ _("View") }}
-			</a>
+			{% if has_view %}
+				<a class="btn btn-secondary" id="{{ field.name }}-button">
+					{{ _("View") }}
+				</a>
+			{% endif %}
 		</div>
 
 		{{ render_errors(field) }}
+		{% if hint %}
+			<small class="form-text text-muted">{{ hint | safe }}</small>
+		{% endif %}
 	</div>
 {%- endmacro %}
 

app/templates/packages/create_edit.html

@@ -116,7 +116,8 @@
 			{{ render_field_prefix_button(form.forums, class_="pkg_meta",
 				pattern="[0-9]+",
 				prefix="forum.minetest.net/viewtopic.php?t=",
-				placeholder=_("Tip: paste in a forum topic URL")) }}
+				placeholder=_("Tip: paste in a forum topic URL"),
+				has_view=True) }}
 			{{ render_field(form.video_url, class_="pkg_meta", hint=_("YouTube videos will be shown in an embed.")) }}
 			{{ render_field(form.donate_url, class_="pkg_meta", hint=_("If blank, the author's donation URL will be used instead.")) }}
 		</fieldset>