Separate HTTP status from content correctness
See this course’s project requirements
A localhost-only client/server diagnostic packet distinguishing name resolution, connection, timeout and HTTP response, with controlled failures and no probing of external systems.
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What to include
- Produce a loopback-only ownership and diagnostic-layer scope card.
- Retain actual localhost resolution and distinctly labeled injected-failure evidence.
- Demonstrate and classify a real owned-loopback refusal with cleanup evidence.
- Verify and classify real local status, media type, and parsed-body cases.
- Retain a controlled connected-silent-read timeline and cleanup record.
- Deliver a layered, repeatable diagnostic packet with actual/simulated cases and exact scope limits.
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
local_diagnostic.py and test-local-network.py create only owned loopback servers on temporary ports. Six cases distinguish actual localhost resolution, injected resolver failure, real HTTP 200/404, real refused local connection, and a real local read timeout. No external host is contacted.
A received HTTP response establishes that the request reached an HTTP handler; status, content type, and body still need separate checks.
Separate HTTP status from content correctness — original worked practice
A received HTTP response establishes that the request reached an HTTP handler; status, content type, and body still need separate checks.
local_diagnostic.py and test-local-network.py create only owned loopback servers on temporary ports. Six cases distinguish actual localhost resolution, injected resolver failure, real HTTP 200/404, real refused local connection, and a real local read timeout. No external host is contacted.
1. Step 1
Read Handler returning /health status 200 and JSON status ready.
You should see: The success contract has status, type, and body.
A received HTTP response establishes that the request reached an HTTP handler; status, content type, and body still need separate checks.
2. Step 2
Run request for /health and inspect all three checked outputs.
You should see: 200, application/json, and parsed ready are verified.
A received HTTP response establishes that the request reached an HTTP handler; status, content type, and body still need separate checks.
3. Step 3
Request /missing on the same owned server.
You should see: The server returns 404 rather than a connection failure.
A received HTTP response establishes that the request reached an HTTP handler; status, content type, and body still need separate checks.
4. Step 4
Record transport success separately from resource status and body assertions.
You should see: An HTTP-layer diagnostic matrix.
A received HTTP response establishes that the request reached an HTTP handler; status, content type, and body still need separate checks.
What to finish
Verify and classify real local status, media type, and parsed-body cases.
Watch for this
Calling an endpoint correct because HTTP 200 arrived without checking the required body.
How can I tell I understand it?
Demonstrate the rule: A received HTTP response establishes that the request reached an HTTP handler; status, content type, and body still need separate checks. Use the supplied variant to distinguish a changed result from a broken implementation.
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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