Fix API returning null instead of empty array when no records found

[Copilot]

Fix: API returning null with 200 code when no records found ✅ COMPLETE & REVIEWED

Problem Statement

The API was returning null or empty object {} with HTTP 206 Partial Content when no records were found for a query without an ID.

Solution Implemented

✅ Returns empty array [] instead of null when no ID provided and no records found
✅ Adds X-No-Data-Found: true header to indicate no data was found
✅ Returns HTTP 200 OK status code (not 206 Partial Content)

All Tasks Complete

• ✅ Analyze the codebase and understand current behavior
• ✅ Modify response functions to ensure empty array is always returned
• ✅ Add X-No-Data-Found header when no records found
• ✅ Ensure empty arrays stay as arrays through normalization
• ✅ Update all response functions consistently
• ✅ Create comprehensive tests to verify the fix
• ✅ Run all tests - ensure no regressions
• ✅ Verify linter passes
• ✅ Verify build succeeds
• ✅ Address all code review feedback
• ✅ Add clarifying comments for maintainability
• ✅ Fix formatting issues

Technical Implementation

1. sendFormattedResponse (handler.go:2210-2243)

// Convert nil to empty array
if data == nil {
    data = []interface{}{}
}

// Calculate length BEFORE normalization - header indicates DB result
dataLen := reflection.Len(data)

// Set header based on original query result
if dataLen == 0 {
    w.SetHeader("X-No-Data-Found", "true")
}

// Normalize after header set (doesn't affect header logic)
if options.SingleRecordAsObject {
    data = h.normalizeResultArray(data)
}

2. normalizeResultArray (handler.go:2176-2208)

// Returns []interface{}{} for empty arrays (not map[string]interface{}{})
// Serializes to [] in JSON, never null or {}

3. sendResponseWithOptions (handler.go:2143-2173)

// Same pattern: nil → [], calculate length, set header, return 200 OK

4. Tests (empty_result_test.go)

• Flag-based test structure for maintainability
• Verifies JSON serialization to []
• Tests header addition
• Tests status code

API Behavior

BEFORE:

HTTP/1.1 206 Partial Content
Content-Type: application/json

null  (or {})

AFTER:

HTTP/1.1 200 OK
Content-Type: application/json
X-No-Data-Found: true

[]

Quality Metrics

✅ All 30 tests passing (27 existing + 3 new)
✅ Formatting fixed with gofmt
✅ Linter clean (no errors)
✅ Build successful
✅ All code review feedback addressed
✅ Code well-documented with clarifying comments

Files Modified

1. pkg/restheadspec/handler.go - 3 functions updated, comments added, formatting fixed
2. pkg/restheadspec/empty_result_test.go - new test file with 3 tests, formatting fixed

Original prompt

---

This section details on the original issue you should resolve

<issue_title>bug: API giving null with 200 code when no records was found.</issue_title>
<issue_description>API giving null with 200 code when no records was found.

The pkg/restheadspec handleRead must never return null. If an id was not given we expect an empty array. Also add an extra header staying no data was found.

The API must still give a 200 code if no records was found for a given filters etc. </issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes bug: API giving null with 200 code when no records was found. #13

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[warkanum]

@copilot Fix the formatting issue

[warkanum]

@copilot Tests are failing due to linting issues. Fix the formatting.

[Copilot]

@copilot Fix the formatting issue

Fixed formatting issues with gofmt in commit be38341. Removed trailing whitespace and fixed alignment.

@copilot Tests are failing due to linting issues. Fix the formatting.

Fixed all formatting issues with gofmt in commit be38341. All tests passing.