Write a separate JSON output
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
Expected output records are [{id: A, minutes:30},{id: B, minutes:45}]; rejected entries name lines 4 and 5.
JSON preserves strings and numbers with explicit structure. Keep accepted records and rejection notes in separate arrays so a consumer cannot confuse a rejected record with usable data.
Write a separate JSON output — original worked practice
JSON preserves strings and numbers with explicit structure. Keep accepted records and rejection notes in separate arrays so a consumer cannot confuse a rejected record with usable data.
Expected output records are [{id: A, minutes:30},{id: B, minutes:45}]; rejected entries name lines 4 and 5.
1. Step 1
Build the two accepted objects.
You should see: Their minutes are numbers 30 and 45.
This keeps the rule and its observable result together.
2. Step 2
Put rejected line notes in rejected rather than records.
You should see: No negative or duplicate record enters records.
This keeps the rule and its observable result together.
3. Step 3
Serialize with json.dumps and inspect the written output.
You should see: The two arrays retain their declared names.
This keeps the rule and its observable result together.
4. Step 4
Reopen or parse the output and compare counts.
You should see: A checked JSON output with 2 accepted and 2 rejected entries.
This keeps the rule and its observable result together.
What to finish
A checked JSON output with 2 accepted and 2 rejected entries.
Watch for this
Writing output before rejecting an input/output path collision.
How can I tell I understand it?
Explain and demonstrate the required distinction: JSON preserves strings and numbers with explicit structure. Keep accepted records and rejection notes in separate arrays so a consumer cannot confuse a rejected record with usable data. 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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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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