lemmyCommentTag.js

const util = require('hexo-util');
const { decycle, encycle } = require('json-cyclic');
const { encode, decode } = require('html-entities');
const fetch = require('node-fetch');
const jsonpath = require('jsonpath');
const fs = require('fs');

const verbose = false;

function errorHtml(msg){
	console.log(`lemmyComment : error. ${msg}`);
	return `<div>lemmyComment : error. ${ encode(msg).replace("\n","<br/>")}</div>`;
}

function encodeQuery(obj) {
	const array = [];
	for (var p in obj)
		if (obj.hasOwnProperty(p))
			array.push(encodeURIComponent(p) + "=" + encodeURIComponent(obj[p]));
	return array.join("&");
}

async function lemmyCommentImpl(self,args){

//	const lemmyConfig = hexo.config.lemmyComment;
//	if(!lemmyConfig) 
//		return errorHtml(`missing lemmyComment in _config.yml`)

	// Hexoの作業フォルダ直下にある設定ファイルを読む
	// このファイルはログイン情報を含むかもしれない
	var lemmyConfigFile = "lemmyConfig.json";
	var lemmyConfig ={};
	try {
		lemmyConfig = JSON.parse(fs.readFileSync(lemmyConfigFile, 'utf8'));
	} catch (err) {
		if (err.code !== 'ENOENT'){
			console.log(`${err} ${lemmyConfigFile}`);
			throw err;
		}
	}

	if(verbose) console.log(`lemmyConfig=${ JSON.stringify(lemmyConfig, null, 2)}`)

	if(!lemmyConfig.site)
		return errorHtml("missing lemmyConfig.site in ${lemmyConfigFile}");

	// assets フォルダに.json をおくと記事として認識されてしまうので、拡張子を画像のソレにする
	var dataFile = `${self.asset_dir}lemmyComment.png`;
	var data = {};
	try {
		data = JSON.parse(fs.readFileSync(dataFile, 'utf8'));
	} catch (err) {
		if (err.code !== 'ENOENT'){
			console.log(`${err} ${dataFile}`);
			throw err;
		}
	}

	var postId = args[0] || data.postId;
	if(verbose) console.log(`postId=${postId}`);

	if(!postId){

		// "https://earphones.juggler.jp/hexo-comment-lemmy-test/"
		// 末尾の/ は除去する必要がある
		var blogUrl = self.permalink
			.replace(/\/$/, "");
		if(verbose) console.log(`blogUrl=${blogUrl}`);
		if( !blogUrl || !blogUrl.startsWith("https://") )
			return errorHtml(`incorrect permalink. ${blogUrl}`);

		var query ={
 			"q" : blogUrl,
 			"type_" : "Url",
 			"sort" : "TopAll",
 			"page" : 1,
 			"limit" : 3
		};

		var url = `${lemmyConfig.site}/api/v2/search?${encodeQuery(query)}`;
		if(verbose) console.log(url);
		var response = await fetch(url);
		var root = await response.json();
		var posts = root.posts;

		// searchリクエスト自体が失敗したらエラー
		if( !posts )
			return errorHtml(`can't use search API. ${JSON.stringify(root, null, 2)}`);

		postId = jsonpath.query(root, '$.posts.0.post.id')[0];

		if( !postId ){
			var warns = [];

			if(self.layout != "posts") 
				warns.push(`- layout is not posts. "${self.layout}"`)

			if(!self.published)
				warns.push(`- this post is not published.`)

			if(!lemmyConfig.community)
				warns.push(`- missing lemmyComment.community in ${lemmyConfigFile}`);

			if(!lemmyConfig.user)
				warns.push(`- missing lemmyComment.user in ${lemmyConfigFile}`);

			if(!lemmyConfig.password)
				warns.push(`- missing lemmyComment.password in ${lemmyConfigFile}`);
				
			if( warns.length > 0 )
				return errorHtml(`autoPost disabled.\n${warns.join("\n")}`);

			// 投稿先のコミュニティーIDを調べる
			if(!lemmyConfig.communityId){
				var query = { "name" : lemmyConfig.community};
				var url = `${lemmyConfig.site}/api/v2/community?${encodeQuery(query)}`;
				if(verbose) console.log(url);
				var response = await fetch(url);
				var root = await response.json();
				if(verbose) console.log(`${JSON.stringify(root, null, 2)}`);
				lemmyConfig.communityId = jsonpath.query(root, '$.community_view.community.id')[0];
				if(!lemmyConfig.communityId)
					return errorHtml(`can't find communityId fo "${lemmyConfig.community}". ${JSON.stringify(root, null, 2)}`);
			}

			// ログイン
			if (!lemmyConfig.lemmyAuth){
				var query = {
					"username_or_email":lemmyConfig.user, 
					"password": lemmyConfig.password
				};
				var url = `${lemmyConfig.site}/api/v2/user/login`;
				if(verbose) console.log(url);
				var response = await fetch(url, {
					method: 'POST',
					headers: { 'Accept': 'application/json', 'Content-Type': 'application/json' },
					body: JSON.stringify(query)
				});
				var root = await response.json();
				if(verbose) console.log(`${JSON.stringify(root, null, 2)}`);
				lemmyConfig.lemmyAuth = jsonpath.query(root, '$.jwt')[0];
				if(!lemmyConfig.lemmyAuth)
					return errorHtml(`login failed. ${JSON.stringify(root, null, 2)}`);
			}

			var query = {
				"name" : self.title,
				"url" : blogUrl,
				"nsfw" : false,
				"body" : "Auto-generated post.",
				"community_id" : lemmyConfig.communityId,
				"auth" : lemmyConfig.lemmyAuth
			};
			var url = `${lemmyConfig.site}/api/v2/post`;
			if(verbose) console.log(url);
			var response = await fetch(url, {
				method: 'POST',
				headers: {
					'Accept': 'application/json', 
					'Content-Type': 'application/json' 
				},
				body: JSON.stringify(query)
			});
			var root = await response.json();
			if(verbose) console.log(`${JSON.stringify(root, null, 2)}`);
			postId = jsonpath.query(root,"$.post_view.post.id")[0];
			if(!postId)
				return errorHtml(`post failed. ${JSON.stringify(root, null, 2)}`);
		}
		
		if( !postId ){
			return errorHtml(`missing postId`);
		}else{
			data.postId = postId;
			fs.writeFileSync(dataFile,JSON.stringify(data),'utf8');
		}
	}
	return `<div id="lemmyComment"></div><script>lemmyComment("${lemmyConfig.site}","${postId}")</script>`;
}

hexo.extend.tag.register('lemmyComment', function(args){
	const self =  decycle(this);

	for( const key of ["date", "updated", "raw","tags","content","categories","site"] ){
		self[key]=`(${typeof self[key]})`;
	}
	if(verbose) console.log(`self=${ JSON.stringify(self, null, 2)}`)

	return lemmyCommentImpl(self,args);
}, {async: true});