Add suggestions with fuzzy text search when no relationship is found

[laurenceisla]

Closes #2569

Contemplating two options:

• Suggest either the parent or child one at a time. If no parent is found, then suggest the closest match and stop there, otherwise, continue looking for the child and suggest its closest match.
• Suggest both parent and child, if neither is found then suggest the closest relationship between them.

Done so far:

• Simple suggestions for parents or children (one at a time)
• Doctests
• Spectests

[steve-chavez]

I wonder if this is expensive if allRels is big, in which case perhaps the hint could be disabled by looking at the map length?

Maybe this could be tested with the apflora schema, by doing time curl .. on a request with bad names.

[laurenceisla]

In apflora, allRels has a size of 305. These are the times that I get:

1. Relationship is found (no fuzzy search):

   $ curl -w "%{time_total}s" -s "http://localhost:3000/ziel?select=ap(*)"

   Response:

   []

   Times:

   0.002485s
   0.002125s
   

2. Relationship not found (fuzzy search for parent)

   $ curl -w "%{time_total}s" -s "http://localhost:3000/ziels?select=ap(*)"

   Response:

   {
       "code": "PGRST200",
       "details": "Searched for a foreign key relationship between 'ziels' and 'ap' in the schema 'apflora', but no matches were found.",
       "hint": "Perhaps you meant 'ziel' instead of 'ziels'.",
       "message": "Could not find a relationship between 'ziels' and 'ap' in the schema cache"
   }

   Times:

   0.072776s
   0.056077s
   

3. Relationship not found (fuzzy search for child)

   $ curl -w "%{time_total}s" -s "http://localhost:3000/ziel?select=app(*)"

   Response:

   {
       "code": "PGRST200",
       "details": "Searched for a foreign key relationship between 'ziel' and 'app' in the schema 'apflora', but no matches were found.",
       "hint": "Perhaps you meant 'ap' instead of 'app'.",
       "message": "Could not find a relationship between 'ziel' and 'app' in the schema cache"
   }

   Times:

   0.035553s
   0.027014s
   

[steve-chavez]

(fuzzy search for parent)
0.072776s
0.056077s
(fuzzy search for child)
0.035553s
0.027014s

So parent takes longer than child because it searches on the full allRels, while child only searches on the relationships that have parent. Makes sense.

[steve-chavez]

Just to make sure I'm understanding this.

If no rel is found:

• Looks for parent suggestions if parent not found
• Looks for child suggestions if children not found and parent is found
• No suggestions if both are found(

Is that correct?

[laurenceisla]

Yes, if both are found then there's an error with the hint, which is more complex to look for.

[steve-chavez]

Suggest both parent and child, if neither is found then suggest the closest relationship between them.

That one is really tricky and likely not worth it. Good that you didn't pursue it further.