Probe multiple URLs in parallel with a bounded worker pool; the N samples
of each URL remain sequential to preserve accurate min/avg/max statistics.
Default auto-concurrency is min(numURLs, 8); -c 1 restores serial mode.
Output is always buffered and printed in original input order. Verified
clean with go test -race.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Examples 1-3: clean global sweep (single, 10 samples, JSON).
Examples 4-8: one failure type each (DNS, refused, timeout, HTTP, TLS).
Example 9: full matrix, all 5 failure types in one run.
Example 10: quick smoke test (-n 1, JSON, --timeout 2s, all types).
Includes runtime estimates and jq filter snippets.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Namespaced go-* targets (build, run, test, test-verbose, check, cover,
fmt, vet, tidy, install, lint, clean) plus umbrella targets that delegate
to them. help is the default. py-* targets will slot in during the Python
port. Updates .gitignore with coverage artifacts.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Extract run(args, stdout, stderr) int from main() for in-process
testability. Fix TLS failure classification (tlsErr now captured from
TLSHandshakeDone hook). Add run_test.go with 14 table-driven in-process
tests and cli_test.go with TestMain + 3 subprocess smoke tests. All
servers use httptest; .invalid TLD for deterministic DNS failures.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Classify network failures (dns/connect/timeout/tls) with distinct exit
codes 2-5. Add --timeout (default 10s) via context.WithTimeout. Add
--fail for exit 6 on HTTP status >= 400. Preserve partial phase timing
up to the failure point. -n sampling continues on network failures,
aggregating successes and reporting fail counts. JSON extended with
succeeded/failed/errors fields.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Add --json flag that emits all results as a JSON array. Schema always
uses min/avg/max per phase (consistent regardless of -n); phases absent
from the request are omitted from the phases object. Output is buffered
until all URLs complete, then printed as one pretty-printed array.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Add probe.Summarize to aggregate N Results into per-phase min/avg/max
stats. Wire up -n/--count flag in main to repeat each URL N times and
display an aligned three-column table. Single-sample output (n=1) is
unchanged. URLs are grouped with a blank line between them.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Instruments HTTP requests with net/http/httptrace.ClientTrace to capture
timestamps for DNS, TCP connect, TLS handshake, TTFB, and body transfer.
TLS row is omitted automatically for plain http:// URLs. Output is an
aligned text table with a separator before the Total row.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
probe.Measure performs an HTTP GET and records total elapsed time from
request start to body fully read. main.go prints URL, status code, and
total for each positional URL argument, exiting 1 on any failure.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Sets up project structure, working conventions (CLAUDE.md), README with
the full assignment and roadmap, seeded CHANGELOG, and a buildable Go
scaffold (Step 0) with flag parsing and stub probe types.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
