waterfalls

callback.js

expb.core.put('/api/posts/:tid([0-9]+)/:pid([0-9]+)', expu.handler(function (req, res, done) {
  userb.checkUser(res, function (err, user) {
    if (err) return done(err);
    var form = postn.getForm(req);
    mysql2.queryOne('select * from thread where id = ?', form.tid, (err, thread) => {
      if (err) return done(err);
      if (!thread) return done(error('INVALID_THREAD'));
      mysql2.queryOne('select * from post where id = ?', form.pid, (err, post) => {
        if (err) return done(err);
        postb.unpackPost(post);
        if (!post || post.tid !== thread.id) return done(error('INVALID_POST'));
        postb.checkCategory(user, thread.cid, function (err, category) {
          if (err) return done(err);
          if (!postb.isEditable(user, post.id, req.session.pids)) return done(error('NOT_AUTHORIZED'));
          var head = postb.isHead(thread, post);
          async2.if(head, function (next) {
            postb.checkCategory(user, form.cid, next); // check new cid
          }, function (err) {
            if (err) return done(err);
            postn.checkForm(form, head, function (err) {
              if (err) return done(err);
              deleteFiles(form, post, function (err) {
                if (err) return done(err);
                postn.saveFiles(form, post, function (err) {
                  if (err) return done(err);
                  post.writer = form.writer;
                  post.text = form.text;
                  if (user.admin) {
                    post.visible = form.visible;
                  }
                  postb.packPost(post);
                  mysql2.query('update post set ? where id = ?', [post, post.id], (err) => {
                    if (err) return done(err);
                    async2.if(head, function (next) {
                      thread.cid = form.cid;
                      thread.title = form.title;
                      thread.writer = form.writer;
                      mysql2.query('update thread set ? where id = ?', [thread, thread.id], next);
                    }, function (err) {
                      if (err) return done(err);
                      res.json({});
                    });
                  });
                });
              });
            });
          });
        });
      });
    });
  });
}));

waterfall.js

async2.waterfall = function (...funcs) {
  let i = 0;
  let e = funcs.length - 1;
  let done = funcs[e];
  let params = [];
  (function loop() {
    if (i === e) {
      return done(null, ...params);
    }
    funcs[i++](...params, (err, ..._params) => {
      if (err) return done(err);
      params = _params;
      setImmediate(loop);
    });
  })();
}

expb.core.put('/api/posts/:tid([0-9]+)/:pid([0-9]+)', expu.handler(function (req, res, done) {
  let user;
  let form;
  let thread;
  let post;
  let head;
  async2.waterfall(
    (done) => {
      userb.checkUser(res, done);
    },
    (_user, done) => {
      user = _user;
      form = postn.getForm(req);
      mysql2.queryOne('select * from thread where id = ?', form.tid, done);
    },
    (_thread, f, done) => {
      thread = _thread;
      if (!thread) return done(error('INVALID_THREAD'));
      mysql2.queryOne('select * from post where id = ?', form.pid, done);
    },
    (_post, f, done) => {
      post = _post;
      postb.unpackPost(post);
      if (!post || post.tid !== thread.id) return done(error('INVALID_POST'));
      postb.checkCategory(user, thread.cid, done);
    },
    (_category, done) => {
      if (!postb.isEditable(user, post.id, req.session.pids)) return done(error('NOT_AUTHORIZED'));
      head = postb.isHead(thread, post);
      if (head) {
        postb.checkCategory(user, form.cid, done); // check new cid
      } else {
        done(null, null);
      }
    },
    (_category, done) => {
      postn.checkForm(form, head, done);
    },
    (done) => {
      deleteFiles(form, post, done);              
    },
    (done) => {
      postn.saveFiles(form, post, done);
    },
    (done) => {
      post.writer = form.writer;
      post.text = form.text;
      if (user.admin) {
        post.visible = form.visible;
      }
      postb.packPost(post);
      mysql2.query('update post set ? where id = ?', [post, post.id], done);
    },
    (r, f, done) => {
      if (head) {
        thread.cid = form.cid;
        thread.title = form.title;
        thread.writer = form.writer;
        mysql2.query('update thread set ? where id = ?', [thread, thread.id], done);
      } else {
        done(null, null, null);
      }
    },
    (r, f, done) => {
      postsr.updateThread(thread.id, done);
    },
    (err) => {
      if (err) return done(err);
      res.json({});
    }
  );
}));