如何用Node.js从REST API获取MongoDB中指定ID的比赛JSON数据

Let's walk through the issues in your code and fix them to get the specific match data you need:

Key Issues in Your Current Code #

• Incorrect Parameter Access: Your route uses :match_id, but you're trying to fetch req.params.id—this means you're actually getting undefined for the ID, so MongoDB runs an empty query ({}) which returns all documents.
• Mismatched Query Field: Your schema uses id as the match ID field (seen in your sample JSON: "id": 1), but your query uses {match} (shorthand for { match: match }), so it's looking for a non-existent field named match.
• Wrong Query Method: find() returns an array of all matching documents. For a single match by ID, you should use findOne() instead.
• Incorrect Response Value: You're returning the match variable (the parameter) instead of the actual query result eachOne.

Corrected Code #

app.get('/api/matches/:match_id', (req, res) => {
  // Convert the string parameter to a number (since your schema's id is numeric)
  const matchId = parseInt(req.params.match_id);

  // Query for the single match where the "id" field matches matchId
  matches.findOne({ id: matchId })
    .then(matchData => {
      if (!matchData) {
        // Return 404 if no match is found
        return res.status(404).json({ message: 'Match not found' });
      }
      // Send the found match data as JSON
      res.json(matchData);
    })
    .catch(error => {
      // Handle database errors with a 500 status
      res.status(500).json({ error: error.message });
    });
});

Additional Notes #

• Type Conversion: req.params values are always strings, so we use parseInt to match the numeric id field in your MongoDB documents—this ensures the query matches correctly (MongoDB enforces strict type matching).
• Error Handling: Added checks for missing matches and database errors to make your API more robust and informative for clients.
• Query Efficiency: findOne() is more efficient than find() for single-document queries since it stops searching after finding the first match.

内容的提问来源于stack exchange，提问作者stone rock