HackMD/lib/models/note.js
2016-10-10 21:04:24 +08:00

522 lines
No EOL
25 KiB
JavaScript

"use strict";
// external modules
var fs = require('fs');
var path = require('path');
var LZString = require('lz-string');
var md = require('markdown-it')();
var metaMarked = require('meta-marked');
var cheerio = require('cheerio');
var shortId = require('shortid');
var Sequelize = require("sequelize");
var async = require('async');
var moment = require('moment');
var DiffMatchPatch = require('diff-match-patch');
var dmp = new DiffMatchPatch();
var S = require('string');
// core
var config = require("../config.js");
var logger = require("../logger.js");
//ot
var ot = require("../ot/index.js");
// permission types
var permissionTypes = ["freely", "editable", "locked", "private"];
module.exports = function (sequelize, DataTypes) {
var Note = sequelize.define("Note", {
id: {
type: DataTypes.UUID,
primaryKey: true,
defaultValue: Sequelize.UUIDV4
},
shortid: {
type: DataTypes.STRING,
unique: true,
allowNull: false,
defaultValue: shortId.generate
},
alias: {
type: DataTypes.STRING,
unique: true
},
permission: {
type: DataTypes.ENUM,
values: permissionTypes
},
viewcount: {
type: DataTypes.INTEGER,
allowNull: false,
defaultValue: 0
},
title: {
type: DataTypes.TEXT
},
content: {
type: DataTypes.TEXT
},
authorship: {
type: DataTypes.TEXT
},
lastchangeAt: {
type: DataTypes.DATE
},
savedAt: {
type: DataTypes.DATE
}
}, {
paranoid: true,
classMethods: {
associate: function (models) {
Note.belongsTo(models.User, {
foreignKey: "ownerId",
as: "owner",
constraints: false
});
Note.belongsTo(models.User, {
foreignKey: "lastchangeuserId",
as: "lastchangeuser",
constraints: false
});
Note.hasMany(models.Revision, {
foreignKey: "noteId",
constraints: false
});
Note.hasMany(models.Author, {
foreignKey: "noteId",
as: "authors",
constraints: false
});
},
checkFileExist: function (filePath) {
try {
return fs.statSync(filePath).isFile();
} catch (err) {
return false;
}
},
checkNoteIdValid: function (id) {
var uuidRegex = /^[0-9a-f]{8}-[0-9a-f]{4}-[1-5][0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/i;
var result = id.match(uuidRegex);
if (result && result.length == 1)
return true;
else
return false;
},
parseNoteId: function (noteId, callback) {
async.series({
parseNoteIdByAlias: function (_callback) {
// try to parse note id by alias (e.g. doc)
Note.findOne({
where: {
alias: noteId
}
}).then(function (note) {
if (note) {
var filePath = path.join(config.docspath, noteId + '.md');
if (Note.checkFileExist(filePath)) {
// if doc in filesystem have newer modified time than last change time
// then will update the doc in db
var fsModifiedTime = moment(fs.statSync(filePath).mtime);
var dbModifiedTime = moment(note.lastchangeAt || note.createdAt);
var body = fs.readFileSync(filePath, 'utf8');
var contentLength = body.length;
var title = Note.parseNoteTitle(body);
body = LZString.compressToBase64(body);
title = LZString.compressToBase64(title);
if (fsModifiedTime.isAfter(dbModifiedTime) && note.content !== body) {
note.update({
title: title,
content: body,
lastchangeAt: fsModifiedTime
}).then(function (note) {
sequelize.models.Revision.saveNoteRevision(note, function (err, revision) {
if (err) return _callback(err, null);
// update authorship on after making revision of docs
var patch = dmp.patch_fromText(LZString.decompressFromBase64(revision.patch));
var operations = Note.transformPatchToOperations(patch, contentLength);
var authorship = note.authorship ? JSON.parse(LZString.decompressFromBase64(note.authorship)) : [];
for (var i = 0; i < operations.length; i++) {
authorship = Note.updateAuthorshipByOperation(operations[i], null, authorship);
}
note.update({
authorship: authorship
}).then(function (note) {
return callback(null, note.id);
}).catch(function (err) {
return _callback(err, null);
});
});
}).catch(function (err) {
return _callback(err, null);
});
} else {
return callback(null, note.id);
}
} else {
return callback(null, note.id);
}
} else {
var filePath = path.join(config.docspath, noteId + '.md');
if (Note.checkFileExist(filePath)) {
Note.create({
alias: noteId,
owner: null,
permission: 'locked'
}).then(function (note) {
return callback(null, note.id);
}).catch(function (err) {
return _callback(err, null);
});
} else {
return _callback(null, null);
}
}
}).catch(function (err) {
return _callback(err, null);
});
},
parseNoteIdByLZString: function (_callback) {
// try to parse note id by LZString Base64
try {
var id = LZString.decompressFromBase64(noteId);
if (id && Note.checkNoteIdValid(id))
return callback(null, id);
else
return _callback(null, null);
} catch (err) {
return _callback(err, null);
}
},
parseNoteIdByShortId: function (_callback) {
// try to parse note id by shortId
try {
if (shortId.isValid(noteId)) {
Note.findOne({
where: {
shortid: noteId
}
}).then(function (note) {
if (!note) return _callback(null, null);
return callback(null, note.id);
}).catch(function (err) {
return _callback(err, null);
});
} else {
return _callback(null, null);
}
} catch (err) {
return _callback(err, null);
}
}
}, function (err, result) {
if (err) {
logger.error(err);
return callback(err, null);
}
return callback(null, null);
});
},
parseNoteInfo: function (body) {
var meta = null;
try {
var obj = metaMarked(body);
body = obj.markdown;
meta = obj.meta;
} catch (err) {
//na
}
if (!meta) meta = {};
var $ = cheerio.load(md.render(body));
return {
title: Note.extractNoteTitle(meta, $),
tags: Note.extractNoteTags(meta, $)
};
},
parseNoteTitle: function (body) {
var meta = null;
try {
var obj = metaMarked(body);
body = obj.markdown;
meta = obj.meta;
} catch (err) {
//na
}
if (!meta) meta = {};
var $ = cheerio.load(md.render(body));
return Note.extractNoteTitle(meta, $);
},
extractNoteTitle: function (meta, $) {
var title = "";
if (meta.title && (typeof meta.title == "string" || typeof meta.title == "number")) {
title = meta.title;
} else {
var h1s = $("h1");
if (h1s.length > 0 && h1s.first().text().split('\n').length == 1)
title = S(h1s.first().text()).stripTags().s;
}
if (!title) title = "Untitled";
return title;
},
decodeTitle: function (title) {
var decodedTitle = LZString.decompressFromBase64(title);
if (decodedTitle) title = decodedTitle;
else title = 'Untitled';
return title;
},
generateWebTitle: function (title) {
title = !title || title == "Untitled" ? "HackMD - Collaborative markdown notes" : title + " - HackMD";
return title;
},
extractNoteTags: function (meta, $) {
var tags = [];
var rawtags = [];
if (meta.tags && (typeof meta.tags == "string" || typeof meta.tags == "number")) {
var metaTags = ('' + meta.tags).split(',');
for (var i = 0; i < metaTags.length; i++) {
var text = metaTags[i].trim();
if (text) rawtags.push(text);
}
} else {
var h6s = $("h6");
h6s.each(function (key, value) {
if (/^tags/gmi.test($(value).text())) {
var codes = $(value).find("code");
for (var i = 0; i < codes.length; i++) {
var text = $(codes[i]).html().trim();
if (text) rawtags.push(text);
}
}
});
}
for (var i = 0; i < rawtags.length; i++) {
var found = false;
for (var j = 0; j < tags.length; j++) {
if (tags[j] == rawtags[i]) {
found = true;
break;
}
}
if (!found)
tags.push(rawtags[i]);
}
return tags;
},
parseMeta: function (meta) {
var _meta = {};
if (meta) {
if (meta.title && (typeof meta.title == "string" || typeof meta.title == "number"))
_meta.title = meta.title;
if (meta.description && (typeof meta.description == "string" || typeof meta.description == "number"))
_meta.description = meta.description;
if (meta.robots && (typeof meta.robots == "string" || typeof meta.robots == "number"))
_meta.robots = meta.robots;
if (meta.GA && (typeof meta.GA == "string" || typeof meta.GA == "number"))
_meta.GA = meta.GA;
if (meta.disqus && (typeof meta.disqus == "string" || typeof meta.disqus == "number"))
_meta.disqus = meta.disqus;
if (meta.slideOptions && (typeof meta.slideOptions == "object"))
_meta.slideOptions = meta.slideOptions;
}
return _meta;
},
updateAuthorshipByOperation: function (operation, userId, authorships) {
var index = 0;
var timestamp = Date.now();
for (var i = 0; i < operation.length; i++) {
var op = operation[i];
if (ot.TextOperation.isRetain(op)) {
index += op;
} else if (ot.TextOperation.isInsert(op)) {
var opStart = index;
var opEnd = index + op.length;
var inserted = false;
// authorship format: [userId, startPos, endPos, createdAt, updatedAt]
if (authorships.length <= 0) authorships.push([userId, opStart, opEnd, timestamp, timestamp]);
else {
for (var j = 0; j < authorships.length; j++) {
var authorship = authorships[j];
if (!inserted) {
var nextAuthorship = authorships[j + 1] || -1;
if (nextAuthorship != -1 && nextAuthorship[1] >= opEnd || j >= authorships.length - 1) {
if (authorship[1] < opStart && authorship[2] > opStart) {
// divide
var postLength = authorship[2] - opStart;
authorship[2] = opStart;
authorship[4] = timestamp;
authorships.splice(j + 1, 0, [userId, opStart, opEnd, timestamp, timestamp]);
authorships.splice(j + 2, 0, [authorship[0], opEnd, opEnd + postLength, authorship[3], timestamp]);
j += 2;
inserted = true;
} else if (authorship[1] >= opStart) {
authorships.splice(j, 0, [userId, opStart, opEnd, timestamp, timestamp]);
j += 1;
inserted = true;
} else if (authorship[2] <= opStart) {
authorships.splice(j + 1, 0, [userId, opStart, opEnd, timestamp, timestamp]);
j += 1;
inserted = true;
}
}
}
if (authorship[1] >= opStart) {
authorship[1] += op.length;
authorship[2] += op.length;
}
}
}
index += op.length;
} else if (ot.TextOperation.isDelete(op)) {
var opStart = index;
var opEnd = index - op;
if (operation.length == 1) {
authorships = [];
} else if (authorships.length > 0) {
for (var j = 0; j < authorships.length; j++) {
var authorship = authorships[j];
if (authorship[1] >= opStart && authorship[1] <= opEnd && authorship[2] >= opStart && authorship[2] <= opEnd) {
authorships.splice(j, 1);
j -= 1;
} else if (authorship[1] < opStart && authorship[1] < opEnd && authorship[2] > opStart && authorship[2] > opEnd) {
authorship[2] += op;
authorship[4] = timestamp;
} else if (authorship[2] >= opStart && authorship[2] <= opEnd) {
authorship[2] = opStart;
authorship[4] = timestamp;
} else if (authorship[1] >= opStart && authorship[1] <= opEnd) {
authorship[1] = opEnd;
authorship[4] = timestamp;
}
if (authorship[1] >= opEnd) {
authorship[1] += op;
authorship[2] += op;
}
}
}
index += op;
}
}
// merge
for (var j = 0; j < authorships.length; j++) {
var authorship = authorships[j];
for (var k = j + 1; k < authorships.length; k++) {
var nextAuthorship = authorships[k];
if (nextAuthorship && authorship[0] === nextAuthorship[0] && authorship[2] === nextAuthorship[1]) {
var minTimestamp = Math.min(authorship[3], nextAuthorship[3]);
var maxTimestamp = Math.max(authorship[3], nextAuthorship[3]);
authorships.splice(j, 1, [authorship[0], authorship[1], nextAuthorship[2], minTimestamp, maxTimestamp]);
authorships.splice(k, 1);
j -= 1;
break;
}
}
}
// clear
for (var j = 0; j < authorships.length; j++) {
var authorship = authorships[j];
if (!authorship[0]) {
authorships.splice(j, 1);
j -= 1;
}
}
return authorships;
},
transformPatchToOperations: function (patch, contentLength) {
var operations = [];
if (patch.length > 0) {
// calculate original content length
for (var j = patch.length - 1; j >= 0; j--) {
var p = patch[j];
for (var i = 0; i < p.diffs.length; i++) {
var diff = p.diffs[i];
switch(diff[0]) {
case 1: // insert
contentLength -= diff[1].length;
break;
case -1: // delete
contentLength += diff[1].length;
break;
}
}
}
// generate operations
var bias = 0;
var lengthBias = 0;
for (var j = 0; j < patch.length; j++) {
var operation = [];
var p = patch[j];
var currIndex = p.start1;
var currLength = contentLength - bias;
for (var i = 0; i < p.diffs.length; i++) {
var diff = p.diffs[i];
switch(diff[0]) {
case 0: // retain
if (i == 0) // first
operation.push(currIndex + diff[1].length);
else if (i != p.diffs.length - 1) // mid
operation.push(diff[1].length);
else // last
operation.push(currLength + lengthBias - currIndex);
currIndex += diff[1].length;
break;
case 1: // insert
operation.push(diff[1]);
lengthBias += diff[1].length;
currIndex += diff[1].length;
break;
case -1: // delete
operation.push(-diff[1].length);
bias += diff[1].length;
currIndex += diff[1].length;
break;
}
}
operations.push(operation);
}
}
return operations;
}
},
hooks: {
beforeCreate: function (note, options, callback) {
// if no content specified then use default note
if (!note.content) {
var body = null;
var filePath = null;
if (!note.alias) {
filePath = config.defaultnotepath;
} else {
filePath = path.join(config.docspath, note.alias + '.md');
}
if (Note.checkFileExist(filePath)) {
var fsCreatedTime = moment(fs.statSync(filePath).ctime);
body = fs.readFileSync(filePath, 'utf8');
note.title = LZString.compressToBase64(Note.parseNoteTitle(body));
note.content = LZString.compressToBase64(body);
if (filePath !== config.defaultnotepath) {
note.createdAt = fsCreatedTime;
}
}
}
// if no permission specified and have owner then give editable permission, else default permission is freely
if (!note.permission) {
if (note.ownerId) {
note.permission = "editable";
} else {
note.permission = "freely";
}
}
return callback(null, note);
},
afterCreate: function (note, options, callback) {
sequelize.models.Revision.saveNoteRevision(note, function (err, revision) {
callback(err, note);
});
}
}
});
return Note;
};