edit conflict management, fix save lockup

i18n/core/en.json

@@ -28,6 +28,8 @@
     "deputy.session.section.saved": "Section saved",
     "deputy.session.section.failed": "Failed to save section",
     "deputy.session.section.missingSection": "The target section is missing from the case page.",
+    "deputy.session.section.conflict.title": "Edit conflict",
+    "deputy.session.section.conflict.help": "Someone else edited the page before you. Deputy will restart to load the new case content. Your changes will be preserved.",
 
     "deputy.session.row.status": "Current page status",
     "deputy.session.row.status.unfinished": "Unfinished",

src/models/ContributionSurveySection.ts

@@ -31,20 +31,26 @@ export default class ContributionSurveySection {
 	 * The original wikitext of this section
 	 */
 	readonly originalWikitext: string;
+	/**
+	 * The revision ID of the wikitext attached to this section.
+	 */
+	readonly revid: number;
 
 	/**
 	 * @param casePage The case page of this section
 	 * @param name The name of this section (based on the heading)
 	 * @param closed Whether this section has been closed (wrapped in collapse templates)
 	 * @param closingComments Closing comments for this section
 	 * @param wikitext The original wikitext of this section
+	 * @param revid The revision ID of the wikitext attached to this section.
 	 */
 	constructor(
 		casePage: DeputyCasePage,
 		name: string,
 		closed: boolean,
 		closingComments: string,
-		wikitext: string
+		wikitext: string,
+		revid: number
 	) {
 		this.casePage = casePage;
 		this.name = name;
@@ -53,6 +59,7 @@ export default class ContributionSurveySection {
 
 		this.originalWikitext = wikitext;
 		this.originallyClosed = closed;
+		this.revid = revid;
 	}
 
 }

src/session/DeputyRootSession.ts

@@ -335,6 +335,7 @@ export default class DeputyRootSession {
 			// User is editing, don't load interface.
 			return;
 		}
+
 		if ( await window.deputy.session.checkForActiveSessionTabs() ) {
 			// User is on another tab, don't load interface.
 			mw.loader.using( [ 'oojs-ui-core', 'oojs-ui-windows' ], () => {
@@ -581,4 +582,14 @@ export default class DeputyRootSession {
 			}
 		}
 	}
+
+	/**
+	 * Restarts the section. This rebuilds *everything* from the ground up, which may
+	 * be required when there's an edit conflict.
+	 */
+	async restartSession() {
+		const casePage = this.casePage;
+		await this.closeSession();
+		await window.deputy.session.DeputyRootSession.continueSession( casePage );
+	}
 }

src/ui/root/DeputyContributionSurveySection.tsx

@@ -36,6 +36,10 @@ export default class DeputyContributionSurveySection implements DeputyUIElement
 	headingName: string;
 	sectionElements: HTMLElement[];
 	originalList: HTMLElement;
+	/**
+	 * Revision ID of the actively-used wikitext. Used for detecting edit conflicts.
+	 */
+	revid: number;
 
 	// UI elements (no OOUI types, fall back to `any`)
 	container: HTMLElement;
@@ -241,18 +245,20 @@ export default class DeputyContributionSurveySection implements DeputyUIElement
 	 *
 	 * @param wikitext Internal use only. Used to skip section loading using existing wikitext.
 	 */
-	async getSection( wikitext?: string ): Promise<ContributionSurveySection> {
+	async getSection( wikitext?: string & { revid: number } ): Promise<ContributionSurveySection> {
 		const collapsible = this.sectionElements.find(
 			( v: HTMLElement ) => v.querySelector( '.mw-collapsible' )
 		)?.querySelector( '.mw-collapsible' ) ?? null;
 
+		const sectionWikitext = await this.casePage.wikitext.getSectionWikitext( this.headingName );
 		return this._section ?? (
 			this._section = new ContributionSurveySection(
 				this.casePage,
 				this.headingName,
 				collapsible != null,
 				collapsible?.querySelector<HTMLElement>( 'th > div' ).innerText,
-				wikitext ?? await this.casePage.wikitext.getSectionWikitext( this.headingName )
+				wikitext ?? sectionWikitext,
+				sectionWikitext.revid
 			)
 		);
 	}
@@ -287,7 +293,9 @@ export default class DeputyContributionSurveySection implements DeputyUIElement
 			}
 		}
 
-		const sectionWikitext = ( await this.getSection() ).originalWikitext;
+		const section = await this.getSection();
+		const sectionWikitext = section.originalWikitext;
+		this.revid = section.revid;
 
 		const wikitextLines = sectionWikitext.split( '\n' );
 		this.rows = [];
@@ -385,10 +393,25 @@ export default class DeputyContributionSurveySection implements DeputyUIElement
 			pageid: this.casePage.pageId,
 			section: sectionId,
 			text: this.wikitext,
+			baserevid: this.revid,
 			summary: decorateEditSummary( this.editSummary )
 		} ).then( function ( data ) {
 			return data;
-		}, function ( code, data ) {
+		}, ( code, data ) => {
+			if ( code === 'editconflict' ) {
+				// Wipe cache.
+				this.casePage.wikitext.resetCachedWikitext();
+				OO.ui.alert(
+					mw.msg( 'deputy.session.section.conflict.help' ),
+					{
+						title: mw.msg( 'deputy.session.section.conflict.title' )
+					}
+				).then( () => {
+					window.deputy.session.rootSession.restartSession();
+				} );
+				return false;
+			}
+
 			mw.notify(
 				<span dangerouslySetInnerHTML={
 					data.errors[ 0 ].html
@@ -480,7 +503,7 @@ export default class DeputyContributionSurveySection implements DeputyUIElement
 
 					// Rebuild the entire section to HTML, and then reopen.
 					const {
-						element, wikitext
+						element, wikitext, revid
 					} = await getSectionHTML( this.casePage.title, sectionId );
 
 					removeElement( this.container );
@@ -503,9 +526,11 @@ export default class DeputyContributionSurveySection implements DeputyUIElement
 
 					if ( !this._section.closed ) {
 						this._section = null;
-						await this.getSection( wikitext );
+						await this.getSection( Object.assign( wikitext, { revid } ) );
 						await this.prepare();
 						oldHeading.insertAdjacentElement( 'afterend', this.render() );
+						// Run this asynchronously.
+						setTimeout( this.loadData.bind( this ), 0 );
 					}
 
 					removeElement( oldHeading );

src/wiki/DeputyCasePageWikitext.ts

@@ -33,19 +33,30 @@ export default class DeputyCasePageWikitext {
 			( this.content = await getPageContent( this.casePage.pageId ) );
 	}
 
+	/**
+	 * Removes the cached wikitext for this page.
+	 */
+	resetCachedWikitext(): void {
+		this.content = undefined;
+	}
+
 	/**
 	 * Gets the wikitext for a specific section. The section will be parsed using the
 	 * wikitext cache if a section title was provided. Otherwise, it will attempt to
 	 * grab the section using API:Query for an up-to-date version.
 	 *
 	 * @param section The section to edit
 	 */
-	async getSectionWikitext( section: string | number ): Promise<string> {
+	async getSectionWikitext( section: string | number ): Promise<string & { revid: number }> {
 		if ( typeof section === 'number' ) {
 			return getPageContent(
 				this.casePage.pageId,
 				{ rvsection: section }
-			).then( ( v ) => v.toString() );
+			).then( ( v ) => {
+				return Object.assign( v.toString(), {
+					revid: v.revid
+				} );
+			} );
 		} else {
 			const wikitext = await this.getWikitext();
 			const wikitextLines = wikitext.split( '\n' );
@@ -70,7 +81,11 @@ export default class DeputyCasePageWikitext {
 				}
 			}
 
-			return sectionLines.join( '\n' );
+			return Object.assign(
+				sectionLines.join( '\n' ), {
+					revid: wikitext.revid
+				}
+			);
 		}
 	}
 

src/wiki/util/getSectionHTML.ts

@@ -14,14 +14,14 @@ export default async function (
 	page: mw.Title | string,
 	section: number | string,
 	extraOptions: Record<string, any> = {}
-): Promise<{ element: HTMLDivElement, wikitext: string }> {
+): Promise<{ element: HTMLDivElement, wikitext: string, revid: number }> {
 	if ( typeof section === 'string' ) {
 		section = await getSectionId( page, section );
 	}
 
 	return MwApi.action.get( {
 		action: 'parse',
-		prop: 'text|wikitext',
+		prop: 'text|wikitext|revid',
 		page: normalizeTitle( page ).getPrefixedText(),
 		section: section,
 		disablelimitreport: true,
@@ -32,7 +32,8 @@ export default async function (
 
 		return {
 			element: temp.children[ 0 ] as HTMLDivElement,
-			wikitext: data.parse.wikitext
+			wikitext: data.parse.wikitext,
+			revid: data.parse.revid
 		};
 	} );
 }