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Import/Export

Sometimes you need to work with HTTP transactions outside the normal recording workflow: importing requests captured by other tools, or exporting test case data for analysis or sharing. Load Tester's import/export features let you move HTTP transaction data in and out of test cases.

This guide covers when to use import/export, how to prepare the files, and step-by-step procedures for both operations.

When to Import Transactions

Import transactions when normal browser recording isn't possible or practical:

Use Case Why Import?
Web service/API testing Client doesn't support proxy configuration (can't record normally)
Mobile app testing App's HTTP client bypasses system proxy settings
Protocol-level testing Need exact control over headers, body, or HTTP version
Reproducing production issues Captured traffic from production using network tools (tcpdump, Wireshark)
Sharing test cases Colleague sends you raw HTTP transactions to import

Recording is almost always easier for browser-based applications. Import is the fallback for when recording isn't an option.

Exporting Transactions

Export transactions when you need to:

Use Case Why Export?
Debugging correlation Examine raw HTTP to understand dynamic values
Sharing with support Send exact request/response to troubleshoot issues
External analysis Use diff tools to compare requests across replays
Documentation Include sample HTTP transactions in technical docs
API testing tools Move transactions to Postman, curl, or other tools

Importing Transactions

Prerequisites

Before importing, you need HTTP request and response files in raw format:

Request file (request.txt): 

GET /api/users/123 HTTP/1.1
Host: example.com
User-Agent: MyApp/1.0
Authorization: Bearer abc123token
Accept: application/json

Response file (response.txt): 

HTTP/1.1 200 OK
Content-Type: application/json
Content-Length: 85

{"id":123,"name":"John Doe","email":"john@example.com"}

Format requirements: - Plain text files (not HAR, PCAP, or other binary formats) - Raw HTTP messages (exactly as sent on the wire) - No extra formatting, headers, or metadata

Capturing HTTP for Import

Use these tools to capture raw HTTP transactions:

Option 1: Browser DevTools (for APIs)

  1. Open Chrome DevTools → Network tab
  2. Right-click request → Copy → Copy as cURL (bash)
  3. Convert cURL to raw HTTP using online tools or manually

Option 2: Network Diagnostic Tools

  • Wireshark - Capture traffic, export as "Follow TCP Stream"
  • tcpdump - Capture with tcpdump -A port 80
  • mitmproxy - Proxy tool that exports raw HTTP

Option 3: API Testing Tools

  • Postman - Export requests as raw HTTP
  • curl - Use -v flag to see raw request/response

Import Procedure

Step 1: Create or Open Test Case

For new test case:

  1. Right-click on Test Cases node in Navigator View
  2. Select: Create Empty Test Case
  3. Name your test case and click OK

Creating an empty test case

For existing test case:

  1. Double-click test case in Navigator View to open Test Case Editor

Step 2: Import Transaction

To add to existing web page:

  1. Right-click on the web page in Test Case Editor
  2. Select: Import → Into Existing Web Page
  3. Browse to select request file
  4. Browse to select response file
  5. Click: OK

To create new web page:

  1. Right-click anywhere in Test Case Editor (not on existing page)
  2. Select: Import → As New Web Page
  3. Browse to select request file
  4. Browse to select response file
  5. Click: OK

Importing a transaction

The transaction appears in the Test Case Editor with the imported request/response data.

Step 3: Verify Import

After importing:

  1. Click the imported transaction in Test Case Editor
  2. Check Request View - Verify URL, headers, body are correct
  3. Check Content View - Verify response body loaded correctly
  4. Run replay - Ensure transaction works in replay

Post-Import Configuration

Imported transactions usually need configuration:

Configuration Why Needed
ASM correlation Dynamic values need to be correlated (session IDs, tokens)
Field configuration Mark fields that should be unique per user
Authentication Configure auth headers if they'll change
Validation rules Add checks to verify responses

Imported transactions won't have automatic correlation, so you'll need to configure ASM manually.

Exporting Transactions

Export lets you save raw HTTP request or response data from any transaction in a test case.

Export Procedure

Step 1: Open Test Case

  1. Double-click test case in Navigator View to open Test Case Editor
  2. Select the transaction you want to export

Step 2: Export Request or Response

  1. Right-click on the transaction
  2. Select: Export
  3. Choose what to export:
  4. Request - HTTP request (URL, headers, body sent to server)
  5. Response - HTTP response (headers, body received from server)
  6. Browse to select save location
  7. Name the file (e.g., request.txt, response.json)
  8. Click: OK

Exporting transaction data

The complete HTTP message is saved to the selected file.

What Gets Exported

Request export includes: 

POST /api/login HTTP/1.1
Host: example.com
Content-Type: application/json
Content-Length: 45

{"username":"testuser","password":"secret123"}

Response export includes: 

HTTP/1.1 200 OK
Content-Type: application/json
Set-Cookie: session=abc123; Path=/

{"token":"xyz789","expires":"2026-02-12T10:00:00Z"}

Exported data is exactly what was sent or received: no formatting, no interpretation, just raw HTTP.

Common Use Cases

Use Case 1: API Testing (Import)

Scenario: Testing a REST API where the client app doesn't support proxy configuration.

Solution:

  1. Use Postman or curl to create API request
  2. Export as raw HTTP request/response
  3. Import into Load Tester
  4. Configure authentication and parameterization
  5. Add to load profile

Use Case 2: Debugging Correlation (Export)

Scenario: Test case replay fails with "session expired" error. Need to see raw HTTP to find session token.

Solution:

  1. Export request from failing replay
  2. Search exported file for session identifiers
  3. Use ASM to correlate the dynamic value
  4. Re-run replay to verify fix

Use Case 3: Sharing Test Cases (Import + Export)

Scenario: Colleague needs to test same API endpoints you're using.

Solution:

  1. Export requests from your test case
  2. Send exported files to colleague
  3. Colleague imports into new test case
  4. Both test cases now use identical HTTP transactions

Troubleshooting

Import Fails: "Invalid HTTP Message"

Symptom: Import dialog shows error about invalid format.

Possible causes: 1. File isn't raw HTTP - Contains HAR, JSON, or other wrapper format 2. Extra whitespace or headers - File includes comments or metadata 3. Incorrect line endings - Windows CRLF vs Unix LF mismatch

Solution: - Verify file contains ONLY raw HTTP (start with GET or HTTP/1.1) - Remove any extra content before/after HTTP message - Convert to Unix line endings if needed

Imported Transaction Won't Replay

Symptom: Imported transaction shows errors during replay.

Likely causes: 1. Missing correlation - Dynamic values (session IDs, tokens) not correlated 2. Hardcoded data - Request contains user-specific data that needs parameterization 3. Authentication expired - Imported auth token no longer valid

Solution: - Run the Configure for Replay wizard to detect and correlate dynamic values - Replace hardcoded data with fields or datasets - Update authentication to use valid credentials

Exported File Too Large

Symptom: Exported response file is hundreds of megabytes.

Cause: Response includes large binary content (images, videos, file downloads).

Solution: - This is expected; exported files include complete response body - If you only need headers, manually edit exported file to remove body - Use external tools (less, head, tail) to view large files without opening in editor

Can't Find Import Menu Option

Symptom: Right-click on transaction doesn't show Import option.

Cause: Import is only available in Test Case Editor, not other views.

Solution: 1. Double-click test case in Navigator View to open Test Case Editor 2. Right-click in Test Case Editor (not in Navigator View or other views) 3. Import option appears in context menu

Best Practices

1. Test Imports Immediately

After importing transactions: - ✅ Run replay to verify transaction works - ✅ Check ASM for required correlation - ✅ Validate response content is correct

Don't assume imports work just because they loaded without errors. Always verify with a replay before adding to load tests.

2. Preserve Original Files

When importing: - ✅ Keep original request/response files - ✅ Document where files came from (tool, date, environment) - ✅ Store with test case documentation

This makes it easier to debug issues or re-import if needed.

3. Export for Documentation

Before making significant changes to test cases: - ✅ Export key transactions for reference - ✅ Include exports in technical documentation - ✅ Use exports to communicate with developers about expected API behavior

Raw HTTP is often clearer than screenshots or prose descriptions when communicating with developers.

4. Prefer Recording When Possible

Import is a workaround, not the primary workflow. Browser recording captures everything automatically (correlation, cookies, redirects), while import requires manual configuration for all of that. Recording is faster and less error-prone. Use import only when recording isn't technically feasible.

Quick Reference

Import Transaction: 1. Right-click in Test Case Editor 2. Import → As New Web Page (or Into Existing Web Page) 3. Select request file and response file 4. Run replay to verify

Export Transaction: 1. Select transaction in Test Case Editor 2. Right-click → Export 3. Choose request or response 4. Save to file

File Format: Plain text, raw HTTP messages only (no HAR, PCAP, JSON wrappers)