gristlabs_grist-core/app/common/TableData.ts

450 lines
16 KiB
TypeScript
Raw Normal View History

/**
* TableData maintains a single table's data.
*/
import {getDefaultForType} from 'app/common/gristTypes';
import fromPairs = require('lodash/fromPairs');
import {ActionDispatcher} from './ActionDispatcher';
import {BulkColValues, CellValue, ColInfo, ColInfoWithId, ColValues, DocAction,
isSchemaAction, ReplaceTableData, RowRecord, TableDataAction} from './DocActions';
import {arrayRemove, arraySplice} from './gutil';
export interface ColTypeMap { [colId: string]: string; }
interface ColData {
colId: string;
type: string;
defl: any;
values: CellValue[];
}
/**
* TableData class to maintain a single table's data.
*
* In the browser's memory, table data needs a representation that's reasonably compact. We
* represent it as column-wise arrays. (An early hope was to allow use of TypedArrays, but since
* types can be mixed, those are not used.)
*/
export class TableData extends ActionDispatcher {
private _tableId: string;
private _isLoaded: boolean = false;
private _fetchPromise?: Promise<void>;
// Storage of the underlying data. Each column is an array, all of the same length. Includes
// 'id' column, containing a reference to _rowIdCol.
private _columns: Map<string, ColData> = new Map();
// Array of all ColData objects, omitting 'id'.
private _colArray: ColData[] = [];
// The `id` column is direct reference to the 'id' column, and contains row ids.
private _rowIdCol: number[] = [];
// Maps row id to index in the arrays in _columns. I.e. it's the inverse of _rowIdCol.
private _rowMap: Map<number, number> = new Map();
constructor(tableId: string, tableData: TableDataAction|null, colTypes: ColTypeMap) {
super();
this._tableId = tableId;
// Initialize all columns to empty arrays, while nothing is yet loaded.
for (const colId in colTypes) {
if (colTypes.hasOwnProperty(colId)) {
const type = colTypes[colId];
const defl = getDefaultForType(type);
const colData: ColData = { colId, type, defl, values: [] };
this._columns.set(colId, colData);
this._colArray.push(colData);
}
}
this._columns.set('id', {colId: 'id', type: 'Id', defl: 0, values: this._rowIdCol});
if (tableData) {
this.loadData(tableData);
}
// TODO: We should probably unload big sets of data when no longer needed. This can be left for
// when we support loading only parts of a table.
}
/**
* Fetch data (as long as a fetch is not in progress), and load it in memory when done.
* Returns a promise that's resolved when data finishes loading, and isLoaded becomes true.
*/
public fetchData(fetchFunc: (tableId: string) => Promise<TableDataAction>): Promise<void> {
if (!this._fetchPromise) {
this._fetchPromise = fetchFunc(this._tableId).then(data => {
this._fetchPromise = undefined;
this.loadData(data);
});
}
return this._fetchPromise;
}
/**
* Populates the data for this table. Returns the array of old rowIds that were loaded before.
*/
public loadData(tableData: TableDataAction|ReplaceTableData): number[] {
const rowIds: number[] = tableData[2];
const colValues: BulkColValues = tableData[3];
const oldRowIds: number[] = this._rowIdCol.slice(0);
reassignArray(this._rowIdCol, rowIds);
for (const colData of this._colArray) {
const values = colValues[colData.colId];
// If colId is missing from tableData, use an array of default values. Note that reusing
// default value like this is only OK because all default values we use are primitive.
reassignArray(colData.values, values || this._rowIdCol.map(() => colData.defl));
}
this._rowMap.clear();
for (let i = 0; i < rowIds.length; i++) {
this._rowMap.set(rowIds[i], i);
}
this._isLoaded = true;
return oldRowIds;
}
// Used by QuerySet to load new rows for onDemand tables.
public loadPartial(data: TableDataAction): void {
// Add the new rows, reusing BulkAddData code.
const rowIds: number[] = data[2];
this.onBulkAddRecord(data, data[1], rowIds, data[3]);
// Mark the table as loaded.
this._isLoaded = true;
}
// Used by QuerySet to remove unused rows for onDemand tables when a QuerySet is disposed.
public unloadPartial(rowIds: number[]): void {
// Remove the unneeded rows, reusing BulkRemoveRecord code.
this.onBulkRemoveRecord(['BulkRemoveRecord', this.tableId, rowIds], this.tableId, rowIds);
}
/**
* Read-only tableId.
*/
public get tableId(): string { return this._tableId; }
/**
* Boolean flag for whether the data for this table is already loaded.
*/
public get isLoaded(): boolean { return this._isLoaded; }
/**
* The number of records loaded in this table.
*/
public numRecords(): number { return this._rowIdCol.length; }
/**
* Returns the specified value from this table.
*/
public getValue(rowId: number, colId: string): CellValue|undefined {
const colData = this._columns.get(colId);
const index = this._rowMap.get(rowId);
return colData && index !== undefined ? colData.values[index] : undefined;
}
/**
* Given a column name, returns a function that takes a rowId and returns the value for that
* column of that row. The returned function is faster than getValue() calls.
*/
public getRowPropFunc(colId: string): undefined | ((rowId: number|"new") => CellValue|undefined) {
const colData = this._columns.get(colId);
if (!colData) { return undefined; }
const values = colData.values;
const rowMap = this._rowMap;
return function(rowId: number|"new") { return rowId === "new" ? "new" : values[rowMap.get(rowId)!]; };
}
/**
* Returns the list of all rowIds in this table, in unspecified and unstable order. Equivalent
* to getColValues('id').
*/
public getRowIds(): ReadonlyArray<number> {
return this._rowIdCol;
}
/**
* Sort and returns the list of all rowIds in this table.
*/
public getSortedRowIds(): number[] {
return this._rowIdCol.slice(0).sort((a, b) => a - b);
}
/**
* Returns the list of colIds in this table, including 'id'.
*/
public getColIds(): string[] {
return Array.from(this._columns.keys());
}
/**
* Returns an unsorted list of all values in the given column. With no intervening actions,
* all arrays returned by getColValues() and getRowIds() are parallel to each other, i.e. the
* values at the same index correspond to the same record.
*/
public getColValues(colId: string): ReadonlyArray<CellValue>|undefined {
const colData = this._columns.get(colId);
return colData ? colData.values : undefined;
}
/**
* Returns a limited-sized set of distinct values from a column. If count is given, limits how many
* distinct values are returned.
*/
public getDistinctValues(colId: string, count: number = Infinity): Set<CellValue>|undefined {
const valColumn = this.getColValues(colId);
if (!valColumn) { return undefined; }
const distinct: Set<CellValue> = new Set();
// Add values to the set until it reaches the desired size, or until there are no more values.
for (let i = 0; i < valColumn.length && distinct.size < count; i++) {
distinct.add(valColumn[i]);
}
return distinct;
}
/**
* Return data in TableDataAction form ['TableData', tableId, [...rowIds], {...}]
*/
public getTableDataAction(): TableDataAction {
const rowIds = this.getRowIds();
return ['TableData',
this.tableId,
rowIds as number[],
fromPairs(
this.getColIds()
.filter(colId => colId !== 'id')
.map(colId => [colId, this.getColValues(colId)! as CellValue[]]))];
}
/**
* Returns the given columns type, if the column exists, or undefined otherwise.
*/
public getColType(colId: string): string|undefined {
const colData = this._columns.get(colId);
return colData ? colData.type : undefined;
}
/**
* Builds and returns a record object for the given rowId.
*/
public getRecord(rowId: number): undefined | RowRecord {
const index = this._rowMap.get(rowId);
if (index === undefined) { return undefined; }
const ret: RowRecord = { id: this._rowIdCol[index] };
for (const colData of this._colArray) {
ret[colData.colId] = colData.values[index];
}
return ret;
}
/**
* Builds and returns the list of all records on this table, in unspecified and unstable order.
*/
public getRecords(): RowRecord[] {
const records: RowRecord[] = this._rowIdCol.map((id) => ({ id }));
for (const {colId, values} of this._colArray) {
for (let i = 0; i < records.length; i++) {
records[i][colId] = values[i];
}
}
return records;
}
public filterRowIds(properties: {[key: string]: any}): number[] {
return this._filterRowIndices(properties).map(i => this._rowIdCol[i]);
}
/**
* Builds and returns the list of records in this table that match the given properties object.
* Properties may include 'id' and any table columns. Returned records are not sorted.
*/
public filterRecords(properties: {[key: string]: any}): RowRecord[] {
const rowIndices: number[] = this._filterRowIndices(properties);
// Convert the array of indices to an array of RowRecords.
const records: RowRecord[] = rowIndices.map(i => ({id: this._rowIdCol[i]}));
for (const {colId, values} of this._colArray) {
for (let i = 0; i < records.length; i++) {
records[i][colId] = values[rowIndices[i]];
}
}
return records;
}
/**
* Returns the rowId in the table where colValue is found in the column with the given colId.
*/
public findRow(colId: string, colValue: any): number {
const colData = this._columns.get(colId);
if (!colData) {
return 0;
}
const index = colData.values.indexOf(colValue);
return index < 0 ? 0 : this._rowIdCol[index];
}
/**
* Returns the first rowId matching the given filters, or 0 if no match. If there are multiple
* matches, it is unspecified which will be returned.
*/
public findMatchingRowId(properties: {[key: string]: CellValue}): number {
const props = Object.keys(properties).map(p => ({col: this._columns.get(p)!, value: properties[p]}));
if (!props.every((p) => p.col)) {
return 0;
}
return this._rowIdCol.find((id, i) =>
props.every((p) => (p.col.values[i] === p.value))
) || 0;
}
/**
* Applies a DocAction received from the server; returns true, or false if it was skipped.
*/
public receiveAction(action: DocAction): boolean {
if (this._isLoaded || isSchemaAction(action)) {
this.dispatchAction(action);
return true;
}
return false;
}
// ---- The following methods implement ActionDispatcher interface ----
protected onAddRecord(action: DocAction, tableId: string, rowId: number, colValues: ColValues): void {
const index: number = this._rowIdCol.length;
this._rowMap.set(rowId, index);
this._rowIdCol[index] = rowId;
for (const {colId, defl, values} of this._colArray) {
values[index] = colValues.hasOwnProperty(colId) ? colValues[colId] : defl;
}
}
protected onBulkAddRecord(action: DocAction, tableId: string, rowIds: number[], colValues: BulkColValues): void {
const index: number = this._rowIdCol.length;
for (let i = 0; i < rowIds.length; i++) {
this._rowMap.set(rowIds[i], index + i);
this._rowIdCol[index + i] = rowIds[i];
}
for (const {colId, defl, values} of this._colArray) {
for (let i = 0; i < rowIds.length; i++) {
values[index + i] = colValues.hasOwnProperty(colId) ? colValues[colId][i] : defl;
}
}
}
protected onRemoveRecord(action: DocAction, tableId: string, rowId: number): void {
// Note that in this implementation, delete + undo will reorder the storage and the ordering
// of rows returned getRowIds() and similar methods.
const index = this._rowMap.get(rowId);
if (index !== undefined) {
const last: number = this._rowIdCol.length - 1;
// We keep the column-wise arrays dense by moving the last element into the freed-up spot.
for (const {values} of this._columns.values()) { // This adjusts _rowIdCol too.
values[index] = values[last];
values.pop();
}
this._rowMap.set(this._rowIdCol[index], index);
this._rowMap.delete(rowId);
}
}
protected onUpdateRecord(action: DocAction, tableId: string, rowId: number, colValues: ColValues): void {
const index = this._rowMap.get(rowId);
if (index !== undefined) {
for (const colId in colValues) {
if (colValues.hasOwnProperty(colId)) {
const colData = this._columns.get(colId);
if (colData) {
colData.values[index] = colValues[colId];
}
}
}
}
}
protected onBulkUpdateRecord(action: DocAction, tableId: string, rowIds: number[], colValues: BulkColValues): void {
for (let i = 0; i < rowIds.length; i++) {
const index = this._rowMap.get(rowIds[i]);
if (index !== undefined) {
for (const colId in colValues) {
if (colValues.hasOwnProperty(colId)) {
const colData = this._columns.get(colId);
if (colData) {
colData.values[index] = colValues[colId][i];
}
}
}
}
}
}
protected onReplaceTableData(action: DocAction, tableId: string, rowIds: number[], colValues: BulkColValues): void {
this.loadData(action as ReplaceTableData);
}
protected onAddColumn(action: DocAction, tableId: string, colId: string, colInfo: ColInfo): void {
if (this._columns.has(colId)) { return; }
const type = colInfo.type;
const defl = getDefaultForType(type);
const colData: ColData = { colId, type, defl, values: this._rowIdCol.map(() => defl) };
this._columns.set(colId, colData);
this._colArray.push(colData);
}
protected onRemoveColumn(action: DocAction, tableId: string, colId: string): void {
const colData = this._columns.get(colId);
if (!colData) { return; }
this._columns.delete(colId);
arrayRemove(this._colArray, colData);
}
protected onRenameColumn(action: DocAction, tableId: string, oldColId: string, newColId: string): void {
const colData = this._columns.get(oldColId);
if (colData) {
colData.colId = newColId;
this._columns.set(newColId, colData);
this._columns.delete(oldColId);
}
}
protected onModifyColumn(action: DocAction, tableId: string, oldColId: string, colInfo: ColInfo): void {
const colData = this._columns.get(oldColId);
if (colData && colInfo.hasOwnProperty('type')) {
colData.type = colInfo.type;
colData.defl = getDefaultForType(colInfo.type);
}
}
protected onRenameTable(action: DocAction, oldTableId: string, newTableId: string): void {
this._tableId = newTableId;
}
protected onAddTable(action: DocAction, tableId: string, columns: ColInfoWithId[]): void {
// A table processing its own addition is a noop
}
protected onRemoveTable(action: DocAction, tableId: string): void {
// Stop dispatching actions if we've been deleted. We might also want to clean up in the future.
this._isLoaded = false;
}
private _filterRowIndices(properties: {[key: string]: any}): number[] {
const rowIndices: number[] = [];
// Array of {col: arrayOfColValues, value: valueToMatch}
const props = Object.keys(properties).map(p => ({col: this._columns.get(p)!, value: properties[p]}));
this._rowIdCol.forEach((id, i) => {
// Collect the indices of the matching rows.
if (props.every((p) => (p.col.values[i] === p.value))) {
rowIndices.push(i);
}
});
return rowIndices;
}
}
function reassignArray<T>(targetArray: T[], sourceArray: T[]): void {
targetArray.length = 0;
arraySplice(targetArray, 0, sourceArray);
}