fix: questions with synonym tags do not show under the origin tag

[hgaol]

fix #680 .

[LinkinStars]

@hgaol Firstly, thank you very much for your contribution.

In the page http://127.0.0.1:8080/tags/kubernetes, user can find all questions that search by synonym tag. That's right you've fixed the issue in this part.

But in the page http://127.0.0.1:8080/search?q=%5Bkubernetes%5D, user can search content via expression such as [tag]. This place still has the same issue that hasn't been fixed.

[hgaol]

@hgaol Firstly, thank you very much for your contribution.

In the page http://127.0.0.1:8080/tags/kubernetes, user can find all questions that search by synonym tag. That's right you've fixed the issue in this part.

But in the page http://127.0.0.1:8080/search?q=%5Bkubernetes%5D, user can search content via expression such as [tag]. This place still has the same issue that hasn't been fixed.

Thanks for figuring it out! I'll fix it later.

[hgaol]

update,

after dive into the SQL logic, I guess the original design is option1. So for the synonym scenario, I think it may need a 2D array for tags. Each dimension is for each tag and its mainTag and synonym tags. Takes 2 tags as example, the logic could be

AND tag_rel0.status = ?
AND tag_rel0.tag_id IN (?, ?)
AND tag_rel1.status = ?
AND tag_rel1.tag_id IN (?)

---

Hi @LinkinStars , one quick question, what's the expected logic when there're multiple tags? option 1 or 2? I think for synonym tags, it's option 2. what about if 2 different tags?

option 1: return objects with both tag1 and tag2.
option 2: return objects with either tag1 or tag2.

[kumfo]

update,

after dive into the SQL logic, I guess the original design is option1. So for the synonym scenario, I think it may need a 2D array for tags. Each dimension is for each tag and its mainTag and synonym tags. Takes 2 tags as example, the logic could be

AND tag_rel0.status = ?
AND tag_rel0.tag_id IN (?, ?)
AND tag_rel1.status = ?
AND tag_rel1.tag_id IN (?)

Hi @LinkinStars , one quick question, what's the expected logic when there're multiple tags? option 1 or 2? I think for synonym tags, it's option 2. what about if 2 different tags?

option 1: return objects with both tag1 and tag2. option 2: return objects with either tag1 or tag2.

Currently, SQL supports multi tag search. If you need to support synonymous tag search, you should directly query synonymous tags when parsing the underlying tags. This way, future search plugins can also be used.

The Search Parse Code ：

search parse

You can add code like ts.tagRepo.GetIDsByMainTagId after line 139.

[hgaol]

Hi @kumfo , I've tested adding ts.tagRepo.GetIDsByMainTagId and added below lines

synIDs, err := sp.tagCommonService.GetTagIDsByMainTagID(ctx, tag.ID)
...
tagIDs = append(tagIDs, synIDs...)

but found it'll only return the objects with all these tags exist. You can find part of the SQL for search. IMO, it does not solve the issue. Take k8s and kubernates as example, when I search [k8s], the expected objects are which have either k8s or kubernates tag, right? similar scenario for searching [kubernates].

...
      `post_update_time`
    FROM
      `question`
      INNER JOIN tag_rel as tag_rel0 ON question.id = tag_rel0.object_id
      INNER JOIN tag_rel as tag_rel1 ON question.id = tag_rel1.object_id
    WHERE
      `question`.`status` < 10
      AND `question`.`show` = 1
      AND tag_rel0.status = 1
      AND tag_rel0.tag_id = tagId1
      AND tag_rel1.status = 1
      AND tag_rel1.tag_id = tagId2
...

[kumfo]

scenario

Sorry! I know what the problem is, and I overlooked the previous search logic. The original tag search must include all these tags at the same time. If you want to modify it now, this search logic will probably need to be processed during the search query.

You need to change the code in file [internal/repo/search_common/search_repo.go](https://github.com/apache/incubator-answer/blob/152934c740d163c2b6345ac2e8c8f542957efa75/internal/repo/search_common/search_repo.go#L150), and you search the comments of // check tag in file. you add synonymous tags query and add or conditions to SQL.

However, if possible, you can parse the synonymous tags in search_parse.go, obtain a separate query parameter, and submit it to this search query. Then the subsequent search plugins can also be modified to be compatible with this query method. but the program will will become more complex.

[hgaol]

Hi @kumfo , exactly! I've pushed new commit about the changed logic for easy communication. In a word, it changes the original SQL from

AND tag_rel0.status = 1
AND tag_rel0.tag_id = tagId1
AND tag_rel1.status = 1
AND tag_rel1.tag_id = tagId2

to

AND tag_rel0.status = ?
AND tag_rel0.tag_id IN (?, ?)
AND tag_rel1.status = ?
AND tag_rel1.tag_id IN (?)

As you mentioned, it changes the interface and all the search plugin need to be modified to be compatible. I'm not sure if there's any better solution. Feel free to let me know and I can implement in this PR. Thanks!

[kumfo]

@hgaol Good Job! but I saw your commit that find you not change the query conditions to in query, You need to change the query conditions,

Original is :

And(builder.Eq{
    ast + ".tag_id": tagID,
    ast + ".status": entity.TagRelStatusAvailable,
})

it need to change like this:

And(builder.In(ast+".tag_id", tagID)).
And(builder.Eq{
    ast + ".status": entity.TagRelStatusAvailable,
})

you can search the code comments of // check tag, there are 3 areas that need to be modified.

[hgaol]

Hi @kumfo , thanks for your review! I found that when there's array in builder.Eq, it'll change it into in. And I've tested it. related documents.

https://pkg.go.dev/xorm.io/[email protected]

but agree that your solution is more clear to indicate that it's a in instead of =.

[hgaol]

I haven't updated for SearchQuestions and SearchAnswers yet. Just want to make sure if it's the expected solution. Do I need to update SearchQuestions and SearchAnswers as well?

[kumfo]

I haven't updated for SearchQuestions and SearchAnswers yet. Just want to make sure if it's the expected solution. Do I need to update SearchQuestions and SearchAnswers as well?

Yeah, you need to update SearchQuestions and SearchAnswers as well. Because there are three ways to search, the default search includes questions and answers. If questions(use is:question) or answers (use is:answer are specified, tag searches can also be used at the same time.

[hgaol]

hi @kumfo , updated. Since Eq{ast+."tag_id": []string{"c", "d"}} works, I didn't change it into builder.In(ast+".tag_id", tagID). And I've tested that it works well.
Feel free to let me know if you prefer builder.In(ast+".tag_id", tagID), and I can update and test it.

[kumfo]

hi @kumfo , updated. Since Eq{ast+."tag_id": []string{"c", "d"}} works, I didn't change it into builder.In(ast+".tag_id", tagID). And I've tested that it works well. Feel free to let me know if you prefer builder.In(ast+".tag_id", tagID), and I can update and test it.

There is no problem in handling it this way. I personally think that using the in explicit identifier will make it clearer for people who read the code.

If you are willing to continue to make changes, I will wait for you to make changes and merge the code in. If you keep the current situation, it doesn't matter, I will also merge the code in.😊

[hgaol]

Updated to replace with builder.In. For search plugins, I'm not quite familiar with and may take some time to ramp up. If it's not urgent, I'd like to try to update them to be compatible as well.

[kumfo]

Hi @hgaol

Well done!, I merged it to dev branch, your submissions will be released in version 1.2.5.