gristlabs_grist-core/app/client/ui/selectBy.ts
Jarosław Sadziński 083a20417e (core) Tests and bug fixes for bidirectional linking
Summary:
- Adding tests for bidirectional linking
- Fixing loop bug for bidirectional linking in custom widgets which use row filtering

Test Plan: New tests

Reviewers: JakubSerafin

Reviewed By: JakubSerafin

Differential Revision: https://phab.getgrist.com/D4070
2023-10-10 15:31:48 +02:00

453 lines
18 KiB
TypeScript

import { ColumnRec, DocModel, TableRec, ViewSectionRec } from 'app/client/models/DocModel';
import { IPageWidget } from 'app/client/ui/PageWidgetPicker';
import { getReferencedTableId } from 'app/common/gristTypes';
import { IOptionFull } from 'grainjs';
import assert from 'assert';
import * as gutil from "app/common/gutil";
import isEqual = require('lodash/isEqual');
// some unicode characters
const BLACK_CIRCLE = '\u2022';
const RIGHT_ARROW = '\u2192';
// Describes a link
export interface IPageWidgetLink {
// The source section id
srcSectionRef: number;
// The source column id
srcColRef: number;
// The target col id
targetColRef: number;
}
export const NoLink = linkId({
srcSectionRef: 0,
srcColRef: 0,
targetColRef: 0
});
const NoLinkOption: IOptionFull<string> = {
label: "Select Widget",
value: NoLink
};
interface LinkNode {
// the tableId
tableId: string;
// is the table a summary table
isSummary: boolean;
// does this node involve an "Attachments" column. Can be tricky if Attachments is one of groupby cols
isAttachments: boolean;
// For a summary table, the set of col refs of the groupby columns of the underlying table
groupbyColumns?: Set<number>;
// list of ids of the sections that are ancestors to this section according to the linked section
// relationship. ancestors[0] is this.section, ancestors[length-1] is oldest ancestor
ancestors: number[];
// For bidirectional linking, cycles are only allowed if all links on that cycle are same-table cursor-link
// this.ancestors only records what the ancestors are, but we need to record info about the edges between them.
// isAncCursLink[i]==true means the link from ancestors[i] to ancestors[i+1] is a same-table cursor-link
// NOTE: (Since ancestors is a list of nodes, and this is a list of the edges between those nodes, this list will
// be 1 shorter than ancestors (if there's no cycle), or will be the same length (if there is a cycle))
isAncestorSameTableCursorLink: boolean[];
// the section record. Must be the empty record sections that are to be created.
section: ViewSectionRec;
// the column record or undefined for the main section node (ie: the node that does not connect to
// any particular column)
column?: ColumnRec;
// the widget type
widgetType: string;
}
// Returns true if this node corresponds to the special 'group' reflist column of a summary table
function isSummaryGroup(node: LinkNode): boolean {
return node.isSummary && node.column?.colId.peek() === "group";
}
// Returns true is the link from `source` to `target` is valid, false otherwise.
function isValidLink(source: LinkNode, target: LinkNode) {
// section must not be the same
if (source.section.getRowId() === target.section.getRowId()) {
return false;
}
// table must match
if (source.tableId !== target.tableId) {
return false;
}
// Can only link to the somewhat special 'group' reflist column of summary tables
// with another ref/reflist column that isn't also a group column
// because otherwise it's equivalent to the usual summary table linking but potentially slower
if (
isSummaryGroup(source) && (!target.column || isSummaryGroup(target)) ||
isSummaryGroup(target)
) {
return false;
}
// Cannot directly link a summary table to a column referencing the source table.
// Instead the ref column must link against the group column of the summary table, which is allowed above.
// The 'group' column name will be hidden from the options so it feels like linking using summaryness.
if (
(source.isSummary && !source.column && target.column) ||
(target.isSummary && !target.column && source.column)
) {
return false;
}
// If the target is a summary table and we're linking based on 'summaryness' (i.e. there are no ref columns)
// then the source must be a less detailed summary table, i.e. having a subset of the groupby columns.
// (or they should be the same summary table for same-record linking, which this check allows through)
if (
!source.column &&
!target.column &&
target.isSummary && !(
source.isSummary &&
gutil.isSubset(source.groupbyColumns!, target.groupbyColumns!)
)
) {
return false;
}
//cannot select from attachments, even though they're implemented as reflists
if (source.isAttachments || target.isAttachments) {
return false;
}
// cannot select from chart
if (source.widgetType === 'chart') {
return false;
}
if (source.widgetType === 'custom') {
// custom widget do not support linking by columns
if (source.tableId !== source.section.table.peek().primaryTableId.peek()) {
return false;
}
// custom widget must allow select by
if (!source.section.allowSelectBy()) {
return false;
}
}
// The link must not create a cycle, unless it's only same-table cursor-links all the way to target
if (source.ancestors.includes(target.section.getRowId())) {
// cycles only allowed for cursor links
if (source.column || target.column || source.isSummary) {
return false;
}
// If one of the section has custom row filter, we can't make cycles.
if (target.section.selectedRowsActive()) {
return false;
}
// We know our ancestors cycle back around to ourselves
// - lets walk back along the cyclic portion of the ancestor chain and verify that each link in that chain is
// a cursor-link
// e.g. if the current link graph is:
// A->B->TGT->C->D->SRC
// (SRC.ancestors):[5][4] [3] [2][1] [0]
// We're verifying the new potential link SRC->TGT, which would turn the graph into:
// [from SRC] -> TGT -> C -> D -> SRC -> [to TGT]
// (Note that A and B will be cut away, since we change TGT's link source)
//
// We need to make sure that each link going backwards from `TGT -> C -> D -> SRC` is a same-table-cursor-link,
// since we disallow cycles with other kinds of links.
// isAncestorCursorLink[i] will tell us if the link going into ancestors[i] is a same-table-cursor-link
// So before we step from i=0 (SRC) to i=1 (D), we check isAncestorCursorLink[0], which tells us about D->SRC
let i;
for (i = 0; i < source.ancestors.length; i++) { // Walk backwards through the ancestors
// Once we hit the target section, we've seen all links that will be part of the cycle, and they've all been valid
if (source.ancestors[i] == target.section.getRowId()) {
break; // Success!
}
// Check that the link to the preceding section is valid
// NOTE! isAncestorSameTableCursorLink could be 1 shorter than ancestors!
// (e.g. if the graph looks like A->B->C, there's 3 ancestors but only two links)
// (however, if there's already a cycle, they'll be the same length ( [from C]->A->B->C, 3 ancestors & 3 links)
// If the link doesn't exist (shouldn't happen?) OR the link is not same-table-cursor, the cycle is invalid
if (i >= source.isAncestorSameTableCursorLink.length ||
!source.isAncestorSameTableCursorLink[i]) { return false; }
}
// If we've hit the last ancestor and haven't found target, error out (shouldn't happen!, we checked for it)
if (i == source.ancestors.length) { throw Error("Array doesn't include targetSection"); }
// Yay, this is a valid cycle of same-table cursor-links
}
return true;
}
// Represents the differents way to reference to a section for linking
type MaybeSection = ViewSectionRec|IPageWidget;
// Returns a list of options with all links that link one of the `source` section to the `target`
// section. Each `opt.value` is a unique identifier (see: linkId() and linkFromId() for more
// detail), and `opt.label` is a human readable representation of the form
// `<section_name>[.<source-col-name>][ -> <target-col-name>]` where the <source-col-name> appears
// only when linking from a reference column, as opposed to linking from the table directly. And the
// <target-col-name> shows only when both <section_name>[.<source-col-name>] is ambiguous.
export function selectBy(docModel: DocModel, sources: ViewSectionRec[],
target: MaybeSection): Array<IOptionFull<string>> {
const sourceNodes = createNodes(docModel, sources);
const targetNodes = createNodes(docModel, [target]);
const options = [NoLinkOption];
for (const srcNode of sourceNodes) {
const validTargets = targetNodes.filter((tgt) => isValidLink(srcNode, tgt));
const hasMany = validTargets.length > 1;
for (const tgtNode of validTargets) {
// a unique identifier for this link
const value = linkId({
srcSectionRef: srcNode.section.getRowId(),
srcColRef: srcNode.column ? srcNode.column.getRowId() : 0,
targetColRef: tgtNode.column ? tgtNode.column.getRowId() : 0,
});
// a human readable description
let label = srcNode.section.titleDef();
// add the source node col name (except for 'group') or nothing for table node
if (srcNode.column && !isSummaryGroup(srcNode)) {
label += ` ${BLACK_CIRCLE} ${srcNode.column.label.peek()}`;
}
// add the target column name (except for 'group') when clarification is needed, i.e. if either:
// - target has multiple valid nodes, or
// - source col is 'group' and is thus hidden.
// Need at least one column name to distinguish from simply selecting by summary table.
// This is relevant when a table has a column referencing itself.
if (tgtNode.column && !isSummaryGroup(tgtNode) && (hasMany || isSummaryGroup(srcNode))) {
label += ` ${RIGHT_ARROW} ${tgtNode.column.label.peek()}`;
}
// add the new option
options.push({ label, value });
}
}
return options;
}
function isViewSectionRec(section: MaybeSection): section is ViewSectionRec {
return Boolean((section as ViewSectionRec).getRowId);
}
// Create all nodes for sections.
function createNodes(docModel: DocModel, sections: MaybeSection[]) {
const nodes = [];
for (const section of sections) {
if (isViewSectionRec(section)) {
nodes.push(...fromViewSectionRec(section));
} else {
nodes.push(...fromPageWidget(docModel, section));
}
}
return nodes;
}
// Creates an array of LinkNode from a view section record.
function fromViewSectionRec(section: ViewSectionRec): LinkNode[] {
if (section.isDisposed()) {
return [];
}
const table = section.table.peek();
const ancestors: number[] = [];
const isAncestorSameTableCursorLink: boolean[] = [];
for (let sec = section; sec.getRowId(); sec = sec.linkSrcSection.peek()) {
if (ancestors.includes(sec.getRowId())) {
// There's a cycle in the existing link graph
// TODO if we're feeling fancy, can test here whether it's an all-same-table cycle and warn if not
// but there's other places we check for that
break;
}
ancestors.push(sec.getRowId());
//Determine if this link is a same-table cursor link
if (sec.linkSrcSection.peek().getRowId()) { // if sec has incoming link
const srcCol = sec.linkSrcCol.peek().getRowId();
const tgtCol = sec.linkTargetCol.peek().getRowId();
const srcTable = sec.linkSrcSection.peek().table.peek();
const srcIsSummary = srcTable.primaryTableId.peek() !== srcTable.tableId.peek();
isAncestorSameTableCursorLink.push(srcCol === 0 && tgtCol === 0 && !srcIsSummary);
}
// NOTE: isAncestorSameTableCursorLink may be 1 shorter than ancestors, since we might skip pushing
// when we hit the last ancestor (which has no incoming link)
// however if we have a cycle (of cursor-links), then they'll be the same length, because we won't skip last push
}
const isSummary = table.primaryTableId.peek() !== table.tableId.peek();
const mainNode: LinkNode = {
tableId: table.primaryTableId.peek(),
isSummary,
isAttachments: isSummary && table.groupByColumns.peek().some(col => col.type.peek() == "Attachments"),
groupbyColumns: isSummary ? table.summarySourceColRefs.peek() : undefined,
widgetType: section.parentKey.peek(),
ancestors,
isAncestorSameTableCursorLink,
section,
};
return fromColumns(table, mainNode);
}
// Creates an array of LinkNode from a page widget.
function fromPageWidget(docModel: DocModel, pageWidget: IPageWidget): LinkNode[] {
if (typeof pageWidget.table !== 'number') { return []; }
let table = docModel.tables.getRowModel(pageWidget.table);
const isSummary = pageWidget.summarize;
const groupbyColumns = isSummary ? new Set(pageWidget.columns) : undefined;
let tableExists = true;
if (isSummary) {
const summaryTable = docModel.tables.rowModels.find(
t => t?.summarySourceTable.peek() && isEqual(t.summarySourceColRefs.peek(), groupbyColumns));
if (summaryTable) {
// The selected source table and groupby columns correspond to this existing summary table.
table = summaryTable;
} else {
// This summary table doesn't exist yet. `fromColumns` will be using columns from the source table.
// Make sure it only uses columns that are in the selected groupby columns.
// The resulting targetColRef will incorrectly be from the source table,
// but will be corrected in GristDoc.saveLink after the summary table is created.
tableExists = false;
}
}
const mainNode: LinkNode = {
tableId: table.primaryTableId.peek(),
isSummary,
isAttachments: false, // hmm, we should need a check here in case attachments col is on the main-node link
// (e.g.: link from summary table with Attachments in group-by) but it seems to work fine as is
groupbyColumns,
widgetType: pageWidget.type,
ancestors: [],
isAncestorSameTableCursorLink: [],
section: docModel.viewSections.getRowModel(pageWidget.section),
};
return fromColumns(table, mainNode, tableExists);
}
function fromColumns(table: TableRec, mainNode: LinkNode, tableExists: boolean = true): LinkNode[] {
const nodes = [mainNode];
const columns = table.columns.peek().peek();
for (const column of columns) {
if (!tableExists && !mainNode.groupbyColumns!.has(column.getRowId())) {
continue;
}
const tableId = getReferencedTableId(column.type.peek());
if (tableId) {
nodes.push({...mainNode, tableId, column, isAttachments: column.type.peek() == "Attachments"});
}
}
return nodes;
}
// Returns an identifier to uniquely identify a link. Here we adopt a simple approach where
// {srcSectionRef: 2, srcColRef: 3, targetColRef: 3} is turned into "[2, 3, 3]".
export function linkId(link: IPageWidgetLink) {
return JSON.stringify([link.srcSectionRef, link.srcColRef, link.targetColRef]);
}
// Returns link's properties from its identifier.
export function linkFromId(linkid: string): IPageWidgetLink {
const [srcSectionRef, srcColRef, targetColRef] = JSON.parse(linkid);
return {srcSectionRef, srcColRef, targetColRef};
}
export class LinkConfig {
public readonly srcSection: ViewSectionRec;
public readonly tgtSection: ViewSectionRec;
// Note that srcCol and tgtCol may be the empty column records if that column is not used.
public readonly srcCol: ColumnRec;
public readonly tgtCol: ColumnRec;
public readonly srcColId: string|undefined;
public readonly tgtColId: string|undefined;
// The constructor throws an exception if settings are invalid. When used from inside a knockout
// computed, the constructor subscribes to all parts relevant for linking.
constructor(tgtSection: ViewSectionRec) {
this.tgtCol = tgtSection.linkTargetCol();
this.srcCol = tgtSection.linkSrcCol();
this.srcSection = tgtSection.linkSrcSection();
this.tgtSection = tgtSection;
this.srcColId = this.srcCol.colId();
this.tgtColId = this.tgtCol.colId();
this._assertValid();
}
// Check if section-linking configuration is valid, and throw exception if not.
private _assertValid(): void {
// Use null for unset cols (rather than an empty ColumnRec) for easier comparisons below.
const srcCol = this.srcCol?.getRowId() ? this.srcCol : null;
const tgtCol = this.tgtCol?.getRowId() ? this.tgtCol : null;
const srcTableId = (srcCol ? getReferencedTableId(srcCol.type()) :
this.srcSection.table().primaryTableId());
const tgtTableId = (tgtCol ? getReferencedTableId(tgtCol.type()) :
this.tgtSection.table().primaryTableId());
const srcTableSummarySourceTable = this.srcSection.table().summarySourceTable();
const tgtTableSummarySourceTable = this.tgtSection.table().summarySourceTable();
try {
assert(Boolean(this.srcSection.getRowId()), "srcSection was disposed");
assert(!tgtCol || tgtCol.parentId() === this.tgtSection.tableRef(), "tgtCol belongs to wrong table");
assert(!srcCol || srcCol.parentId() === this.srcSection.tableRef(), "srcCol belongs to wrong table");
assert(this.srcSection.getRowId() !== this.tgtSection.getRowId(), "srcSection links to itself");
// We usually expect srcTableId and tgtTableId to be non-empty, but there's one exception:
// when linking two summary tables that share a source table (which we can check directly)
// and the source table is hidden by ACL, so its tableId is empty from our perspective.
if (!(srcTableSummarySourceTable !== 0 && srcTableSummarySourceTable === tgtTableSummarySourceTable)) {
assert(tgtTableId, "tgtCol not a valid reference");
assert(srcTableId, "srcCol not a valid reference");
}
assert(srcTableId === tgtTableId, "mismatched tableIds");
// If this section has a custom link filter, it can't create cycles.
if (this.tgtSection.selectedRowsActive()) {
// Make sure we don't have a cycle.
let src = this.tgtSection.linkSrcSection();
while (!src.isDisposed() && src.getRowId()) {
assert(src.getRowId() !== this.srcSection.getRowId(),
"Sections with filter linking can't be part of a cycle (same record linking)'");
src = src.linkSrcSection();
}
}
} catch (e) {
throw new Error(`LinkConfig invalid: ` +
`${this.srcSection.getRowId()}:${this.srcCol?.getRowId()}[${srcTableId}] -> ` +
`${this.tgtSection.getRowId()}:${this.tgtCol?.getRowId()}[${tgtTableId}]: ${e}`);
}
}
}