Report invalid records and file errors
See this course’s project requirements
A local command-line converter that validates fictional attendance CSV, writes JSON to a chosen output and reports rejected rows without altering input.
Keep your working files in your own notebook or software. Save a private description, checklist, and work link in My Proof.
What to include
- A converter contract with two accepted and two rejected records.
- A CSV-to-typed-record trace with invalid-value evidence.
- A failure report distinguishing rejected rows from failed runs.
- A checked JSON output with 2 accepted and 2 rejected entries.
- A reusable command contract and a missing-argument test.
- A repeatable local CSV converter with failure and preservation evidence.
Review and revise
Use these criteria to check your work and choose what to improve.
- The implementation or declared simulation follows the supplied contract and retains inspectable original inputs.
- Normal, boundary and rejected cases are recorded with expected versus observed results.
- The changed case has a correct explanation and does not rely on hidden state.
- The project includes source, outputs, instructions and honest tool, privacy and verification limits.
Want more background?
The idea in everyday life
Data line numbers are 2 A,3 B,4 C and 5 B because the header is line 1. The rejected report uses line 4 and 5, with no copied sensitive payload.
A rejected record is different from a file that could not be read. Row rejection can permit other valid rows to finish; an unreadable input or wrong schema stops the run with exit code 2.
Report invalid records and file errors — original worked practice
A rejected record is different from a file that could not be read. Row rejection can permit other valid rows to finish; an unreadable input or wrong schema stops the run with exit code 2.
Data line numbers are 2 A,3 B,4 C and 5 B because the header is line 1. The rejected report uses line 4 and 5, with no copied sensitive payload.
1. Step 1
Number lines including the header.
You should see: Invalid records occur on lines 4 and 5.
This keeps the rule and its observable result together.
2. Step 2
Distinguish row errors from missing input.
You should see: Row errors create a report; missing file prevents conversion.
This keeps the rule and its observable result together.
3. Step 3
Trace parser.exit(2, message) on a file failure.
You should see: A nonzero exit signals that a usable run did not complete.
This keeps the rule and its observable result together.
4. Step 4
Write separate record and run status in the test log.
You should see: A failure report distinguishing rejected rows from failed runs.
This keeps the rule and its observable result together.
What to finish
A failure report distinguishing rejected rows from failed runs.
Watch for this
Silently discarding rejected lines rather than preserving the source row number and the declared generic reason invalid record. Inspect that fictional source row to distinguish a duplicate ID from an invalid minutes value.
How can I tell I understand it?
Explain and demonstrate the required distinction: A rejected record is different from a file that could not be read. Row rejection can permit other valid rows to finish; an unreadable input or wrong schema stops the run with exit code 2. Show a changed input and the expected result without weakening this contract.
Quick knowledge check
Answer all 3 questions. Get at least 2 right and the lesson completes automatically.
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Answer all 3 questions above and get at least 2 right. You can review the explanations and try again.
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Source & access notes · checked 2026-10-01
Relevant documented module/API behavior inspected during expansion authoring; actual execution evidence is recorded separately. No grant eligibility is established.
Access: Official page retrieved with the web reader on 2026-10-01. Documentation reading does not certify execution in every native tool or browser.
Reuse: Original local practice files, fictional data, worked examples and questions. Concepts paraphrased and linked; source exercises are not copied.
Source & access notes · checked 2026-10-01
Relevant documented module/API behavior inspected during expansion authoring; actual execution evidence is recorded separately. No grant eligibility is established.
Access: Official page retrieved with the web reader on 2026-10-01. Documentation reading does not certify execution in every native tool or browser.
Reuse: Original local practice files, fictional data, worked examples and questions. Concepts paraphrased and linked; source exercises are not copied.
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