gristlabs_grist-core/app/server/lib/RowAccess.ts
Paul Fitzpatrick 0e2deecc55 (core) implement cleaner row-level access control for outgoing messages
Summary:
This implements row-level access control for outgoing messages, replacing the document reloading placeholder that was there before.

 * Prior to broadcasting messages, GranularAccess is notified of actions+undo.
 * While broadcasting messages to different sessions, if we find we need row level access control information, rows before and after the change are reconstructed.
 * Messages are rewritten if rows that were previously forbidden are now allowed, and vice versa.

The diff is somewhat under-tested and under-optimized. Next step would be to implement row-level access control for incoming actions, which may result in some rejiggering of the code from this diff to avoid duplication of effort under some conditions.

Test Plan: added test

Reviewers: dsagal

Reviewed By: dsagal

Differential Revision: https://phab.getgrist.com/D2670
2020-11-30 16:28:33 -05:00

64 lines
2.9 KiB
TypeScript

import { AddRecord, BulkAddRecord, BulkRemoveRecord, BulkUpdateRecord, DocAction, getTableId,
RemoveRecord, ReplaceTableData, TableDataAction, UpdateRecord } from "app/common/DocActions";
import { getSetMapValue } from "app/common/gutil";
/**
* A little class for tracking pre-existing rows touched by a sequence of DocActions for
* a given table.
*/
class RowIdTracker {
public blockedIds = new Set<number>(); // row ids minted within the DocActions (so NOT pre-existing).
public blocked: boolean = false; // set if all pre-existing rows are wiped/
public ids = new Set<number>(); // set of pre-existing rows touched.
}
/**
* This gets a list of pre-existing rows that the DocActions may touch. Returns
* a list of form [tableId, Set{rowId1, rowId2, ...}].
*/
export function getRelatedRows(docActions: DocAction[]): ReadonlyArray<readonly [string, Set<number>]> {
// Relate tableIds for tables with what they were before the actions, if renamed.
const tableIds = new Map<string, string>();
const rowIds = new Map<string, RowIdTracker>();
for (const docAction of docActions) {
const currentTableId = getTableId(docAction);
const tableId = tableIds.get(currentTableId) || currentTableId;
if (docAction[0] === 'RenameTable') {
tableIds.delete(currentTableId);
tableIds.set(docAction[2], tableId);
continue;
}
// tableId will now be that prior to docActions, regardless of renames.
const tracker = getSetMapValue(rowIds, tableId, () => new RowIdTracker());
if (docAction[0] === 'RemoveRecord' || docAction[0] === 'BulkRemoveRecord' ||
docAction[0] === 'UpdateRecord' || docAction[0] === 'BulkUpdateRecord') {
// All row ids mentioned are external, unless created within this set of DocActions.
if (!tracker.blocked) {
for (const id of getRowIdsFromDocAction(docAction)) {
if (!tracker.blockedIds.has(id)) { tracker.ids.add(id); }
}
}
} else if (docAction[0] === 'AddRecord' || docAction[0] === 'BulkAddRecord') {
// All row ids mentioned are created within this set of DocActions, and are not external.
for (const id of getRowIdsFromDocAction(docAction)) { tracker.blockedIds.add(id); }
} else if (docAction[0] === 'ReplaceTableData' || docAction[0] === 'TableData') {
// No pre-existing rows can be referred to for this table from now on.
tracker.blocked = true;
}
}
return [...rowIds.entries()].map(([tableId, tracker]) => [tableId, tracker.ids] as const);
}
/**
* Tiny helper to get the row ids mentioned in a record-related DocAction as a list
* (even if the action is not a bulk action).
*/
export function getRowIdsFromDocAction(docActions: RemoveRecord | BulkRemoveRecord | AddRecord |
BulkAddRecord | UpdateRecord | BulkUpdateRecord | ReplaceTableData | TableDataAction) {
const ids = docActions[2];
return (typeof ids === 'number') ? [ids] : ids;
}