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nodebb/src/posts/diffs.js

153 lines
4.4 KiB
JavaScript

'use strict';
const validator = require('validator');
const diff = require('diff');
const db = require('../database');
const meta = require('../meta');
const plugins = require('../plugins');
const translator = require('../translator');
module.exports = function (Posts) {
const Diffs = {};
Posts.diffs = Diffs;
Diffs.exists = async function (pid) {
if (meta.config.enablePostHistory !== 1) {
return false;
}
const numDiffs = await db.listLength(`post:${pid}:diffs`);
return !!numDiffs;
};
Diffs.get = async function (pid, since) {
const timestamps = await Diffs.list(pid);
if (!since) {
since = 0;
}
// Pass those made after `since`, and create keys
const keys = timestamps.filter(t => (parseInt(t, 10) || 0) > since)
.map(t => `diff:${pid}.${t}`);
return await db.getObjects(keys);
};
Diffs.list = async function (pid) {
return await db.getListRange(`post:${pid}:diffs`, 0, -1);
};
Diffs.save = async function (data) {
const { pid, uid, oldContent, newContent, edited } = data;
const editTimestamp = edited || Date.now();
const patch = diff.createPatch('', newContent, oldContent);
await Promise.all([
db.listPrepend(`post:${pid}:diffs`, editTimestamp),
db.setObject(`diff:${pid}.${editTimestamp}`, {
uid: uid,
pid: pid,
patch: patch,
}),
]);
};
Diffs.load = async function (pid, since, uid) {
since = getValidatedTimestamp(since);
const post = await postDiffLoad(pid, since, uid);
post.content = String(post.content || '');
const result = await plugins.hooks.fire('filter:parse.post', { postData: post });
result.postData.content = translator.escape(result.postData.content);
return result.postData;
};
Diffs.restore = async function (pid, since, uid, req) {
since = getValidatedTimestamp(since);
const post = await postDiffLoad(pid, since, uid);
return await Posts.edit({
uid: uid,
pid: pid,
content: post.content,
req: req,
timestamp: since,
});
};
Diffs.delete = async function (pid, timestamp, uid) {
getValidatedTimestamp(timestamp);
const [post, diffs, timestamps] = await Promise.all([
Posts.getPostSummaryByPids([pid], uid, { parse: false }),
Diffs.get(pid),
Diffs.list(pid),
]);
const timestampIndex = timestamps.indexOf(timestamp);
const lastTimestampIndex = timestamps.length - 1;
if (timestamp === String(post[0].timestamp)) {
// Deleting oldest diff, so history rewrite is not needed
return Promise.all([
db.delete(`diff:${pid}.${timestamps[lastTimestampIndex]}`),
db.listRemoveAll(`post:${pid}:diffs`, timestamps[lastTimestampIndex]),
]);
}
if (timestampIndex === 0 || timestampIndex === -1) {
throw new Error('[[error:invalid-data]]');
}
const postContent = validator.unescape(post[0].content);
const versionContents = {};
for (let i = 0, content = postContent; i < timestamps.length; ++i) {
versionContents[timestamps[i]] = applyPatch(content, diffs[i]);
content = versionContents[timestamps[i]];
}
/* eslint-disable no-await-in-loop */
for (let i = lastTimestampIndex; i >= timestampIndex; --i) {
// Recreate older diffs with skipping the deleted diff
const newContentIndex = i === timestampIndex ? i - 2 : i - 1;
const timestampToUpdate = newContentIndex + 1;
const newContent = newContentIndex < 0 ? postContent : versionContents[timestamps[newContentIndex]];
const patch = diff.createPatch('', newContent, versionContents[timestamps[i]]);
await db.setObject(`diff:${pid}.${timestamps[timestampToUpdate]}`, { patch });
}
return Promise.all([
db.delete(`diff:${pid}.${timestamp}`),
db.listRemoveAll(`post:${pid}:diffs`, timestamp),
]);
};
async function postDiffLoad(pid, since, uid) {
// Retrieves all diffs made since `since` and replays them to reconstruct what the post looked like at `since`
const [post, diffs] = await Promise.all([
Posts.getPostSummaryByPids([pid], uid, { parse: false }),
Posts.diffs.get(pid, since),
]);
// Replace content with re-constructed content from that point in time
post[0].content = diffs.reduce(applyPatch, validator.unescape(post[0].content));
return post[0];
}
function getValidatedTimestamp(timestamp) {
timestamp = parseInt(timestamp, 10);
if (isNaN(timestamp)) {
throw new Error('[[error:invalid-data]]');
}
return timestamp;
}
function applyPatch(content, aDiff) {
const result = diff.applyPatch(content, aDiff.patch, {
fuzzFactor: 1,
});
return typeof result === 'string' ? result : content;
}
};