$select doesn't work in find?

[beeplin]

$select doesn't work in find operation. I found that the source code for $select is not the same as that in other packages like feathers-mongodb or feathers-nedb. Normally the code would be like this:

    // $select uses a specific find syntax, so it has to come first.
    if (filters.$select) {
      query = this.Model.find(params.query, getSelect(filters.$select));
    }

but in feathers-mongoose (via github) it is like:

    // $select uses a specific find syntax, so it has to come first.
    if (filters.$select && filters.$select.length) {
      let fields = {};

      for (let key of filters.$select) {
        fields[key] = 1;
      }

      query.select(fields);
    }

and furthermore, in the actually feathers-mongoose npm package (v3.3.6) the source code is:

      // $select uses a specific find syntax, so it has to come first.
      if (filters.$select && filters.$select.length) {
        var fields = {};

        var _iteratorNormalCompletion = true;
        var _didIteratorError = false;
        var _iteratorError = undefined;

        try {
          for (var _iterator = filters.$select[Symbol.iterator](), _step; !(_iteratorNormalCompletion = (_step = _iterator.next()).done); _iteratorNormalCompletion = true) {
            var key = _step.value;

            fields[key] = 1;
          }
        } catch (err) {
          _didIteratorError = true;
          _iteratorError = err;
        } finally {
          try {
            if (!_iteratorNormalCompletion && _iterator.return) {
              _iterator.return();
            }
          } finally {
            if (_didIteratorError) {
              throw _iteratorError;
            }
          }
        }

        query.select(fields);
      }

[ekryski]

@beeplin how are you passing it in your code? We have tests that cover this that are passing. If needs to be under params.query.$select and you need to make sure your object is structured properly. See this section.

[beeplin]

I just cloned feathers-chat project, changed it's service from nedb to mongoose, and modify /public/react-chat/app.jsx L128 to:

    // Find the last 10 messages
    messageService.find({
      query: {
        $select: {
          _id: 0,
          'text': 0
        },
        $sort: { createdAt: -1 },
        $limit: this.props.limit || 10
      }
    }).then(page => this.setState({ messages: page.data.reverse() }));

other stuffs work perfectly including $sort, &skit and #limit, but $select seems to be ignored.

[ekryski]

Hmm. ok we'll have to look into it. Unfortunately, it won't happen today.

[beeplin]

take ur time. :) if this got solved I d like to transform my old project from mongodb to mongoose and enjoy feathers~~

[jamesjnadeau]

I'm not sure if others have noticed this, and it has to do with query parsing in your client, but I found that depending on how your request handler parses the query, and creates the subsequent url, you might have issues that are hard to debug without digging deeper.

@beeplin can you please try the following and see if you get what you are looking for:

// Find the last 10 messages
    messageService.find({
      query: {
        '$select[_id]': 0,
        '$select[text]': 0,
        $sort: { createdAt: -1 },
        $limit: this.props.limit || 10
      }
    }).then(page => this.setState({ messages: page.data.reverse() }));

you're probably going to have to do the same to the $sort variable, or pass it in via a string like:

$sort: '-createdAt'

[daffl]

I think the docs are wrong. The service tests use an array. Can you try

    messageService.find({
      query: {
        $select: ['_id', 'text' ],
        $sort: { createdAt: -1 },
        $limit: this.props.limit || 10
      }
    }).then(page => this.setState({ messages: page.data.reverse() }));

[daffl]

If that is the case, removing fields can probably be done best using the remove hook instead.

[daffl]

This was indeed a mistake in the documentation, sorry about that. It is fixed now and works as I described above.

[beeplin]

so this array syntax only works for mongoose or for all other db adapters too?

[marshallswain]

@beeplin This is part of our shared tests for all adapters: https://github.com/feathersjs/feathers-service-tests/blob/master/src/common-tests.js#L166

So all of them should support it.

[beeplin]

got it. Thanks~

来自 魅族 MX5

-------- 原始邮件 --------
发件人：Marshall Thompson notifications@github.com
时间：周三 3月23日 16:10
收件人：feathersjs/feathers-mongoose feathers-mongoose@noreply.github.com
抄送：Beep LIN beeplin@gmail.com
主题：Re: [feathers-mongoose] $select doesn't work in find? (#71)

@beeplin This is part of our shared tests for all adapters: https://github.com/feathersjs/feathers-service-tests/blob/master/src/common-tests.js#L166 So all of them should support it. —You are receiving this because you were mentioned.Reply to this email directly or view it on GitHub