---
phase: 08-external-http
verified: 2026-03-11T14:00:00Z
status: passed
score: 13/13 must-haves verified
re_verification: false
---

# Phase 8: External HTTP Connectivity Verification Report

**Phase Goal:** Add external HTTP connectivity validation mode — challenges can validate that a service responds to HTTP requests from outside the cluster (no source pod needed), enabling new types of networking challenges.
**Verified:** 2026-03-11T14:00:00Z
**Status:** passed
**Re-verification:** No — initial verification

---

## Goal Achievement

### Observable Truths — Plan 01 (EXT-01/02/03)

| #  | Truth | Status | Evidence |
|----|-------|--------|----------|
| 1  | A connectivity spec with `mode: external` parses without error | VERIFIED | `TestParse_Connectivity_ExternalMode` passes; loader.go line 234 accepts `spec.Mode == "external"` |
| 2  | A connectivity spec with `mode: external` + `sourcePod` set returns a parse-time error | VERIFIED | `TestParse_Connectivity_ExternalModeWithSourcePod` passes; error message contains "incompatible with sourcePod" |
| 3  | A connectivity spec with an unknown mode value returns a parse-time error | VERIFIED | `TestParse_Connectivity_InvalidMode` passes; error message contains "invalid mode" |
| 4  | A connectivity spec with no `mode` field parses unchanged — full backwards compatibility | VERIFIED | `TestParse_Connectivity_NoMode` passes; `spec.Mode == ""` |
| 5  | A `ConnectivityCheck` with `hostHeader` set parses and is accessible in the typed spec | VERIFIED | `HostHeader string` field present in `ConnectivityCheck` at types.go line 210; test coverage via `TestCheckExternalConnectivity_HostHeader` |
| 6  | A sslip.io URL in a connectivity target parses without modification | VERIFIED | `TestParse_Connectivity_SslipIO` passes; URL preserved unchanged |

### Observable Truths — Plan 02 (EXT-01/02/03/04)

| #  | Truth | Status | Evidence |
|----|-------|--------|----------|
| 7  | A connectivity validation with `mode: external` sends HTTP request from CLI host via net/http — no pod exec | VERIFIED | `executeConnectivity` branches on `spec.Mode == "external"` at executor.go line 410; `TestExecuteConnectivity_ExternalMode` passes with nil K8s clients |
| 8  | External check with `hostHeader` sets `req.Host` on the outgoing request (not req.Header) | VERIFIED | executor.go line 521: `req.Host = target.HostHeader`; `TestCheckExternalConnectivity_HostHeader` passes and asserts `r.Host == "myapp.example.com"` |
| 9  | External check returns passed=true when server responds with the expected status code | VERIFIED | `TestCheckExternalConnectivity_Success` passes |
| 10 | External check returns passed=false with message containing "got status 404" when wrong status code | VERIFIED | `TestCheckExternalConnectivity_WrongStatus` passes |
| 11 | External check with `expectedStatusCode: 0` returns passed=true when connection refused | VERIFIED | `TestCheckExternalConnectivity_BlockedConnection` passes; message contains "blocked" |
| 12 | External check returns passed=false when connection refused and expectedStatusCode != 0 | VERIFIED | `TestCheckExternalConnectivity_ConnectionRefused` passes; message contains "failed" |
| 13 | All existing internal connectivity tests continue to pass unchanged | VERIFIED | 578 tests pass across validation package; 0 regressions |

**Score:** 13/13 truths verified

---

### Required Artifacts

| Artifact | Expected | Status | Details |
|----------|----------|--------|---------|
| `internal/validation/types.go` | `Mode string` on `ConnectivitySpec`; `HostHeader string` on `ConnectivityCheck` | VERIFIED | Both fields present with `yaml:"mode,omitempty"` and `yaml:"hostHeader,omitempty"` tags |
| `internal/validation/loader.go` | Parse-time validation: rejects `mode:external + sourcePod`; rejects unknown modes | VERIFIED | TypeConnectivity case at line 228 implements both checks; error messages match test assertions |
| `internal/validation/loader_test.go` | 5 new tests covering EXT-01/02/03 behaviors | VERIFIED | `TestParse_Connectivity_ExternalMode`, `TestParse_Connectivity_ExternalModeWithSourcePod`, `TestParse_Connectivity_SslipIO`, `TestParse_Connectivity_InvalidMode`, `TestParse_Connectivity_NoMode` all present and passing |
| `internal/validation/executor.go` | `checkExternalConnectivity` method; `checkExternalConnectivityAll` helper; `executeConnectivity` mode branch | VERIFIED | All three present; `net/http` imported; `req.Host` pattern used correctly |
| `internal/validation/executor_test.go` | Unit tests for external mode using `httptest.NewServer` | VERIFIED | 7 test functions (13 test cases) present at lines 2944–3073 |

---

### Key Link Verification

| From | To | Via | Status | Details |
|------|----|-----|--------|---------|
| `loader.go` TypeConnectivity case | `types.go ConnectivitySpec.Mode` | `yaml.Unmarshal` → `spec.Mode` field access | VERIFIED | `spec.Mode` accessed at loader.go lines 234, 239 |
| `executor.go executeConnectivity` | `executor.go checkExternalConnectivityAll` | `spec.Mode == "external"` branch | VERIFIED | executor.go lines 410–412: `if spec.Mode == "external" { return e.checkExternalConnectivityAll(ctx, spec) }` |
| `executor.go checkExternalConnectivity` | `net/http` | `http.NewRequestWithContext` + `req.Host` override + `client.Do` | VERIFIED | executor.go lines 512, 521, 533; `req.Host = target.HostHeader` is the correct Go pattern for Host wire header override |

---

### Requirements Coverage

| Requirement | Source Plan | Description | Status | Evidence |
|-------------|-------------|-------------|--------|----------|
| EXT-01 | 08-01, 08-02 | HTTP external connectivity via `mode: external` — CLI net/http, no pod exec | SATISFIED | Mode field in types.go; parse-time validation in loader.go; `executeConnectivity` branch + `checkExternalConnectivity` in executor.go |
| EXT-02 | 08-01, 08-02 | `hostHeader` field for Ingress/Gateway virtual-host routing | SATISFIED | `HostHeader` field in `ConnectivityCheck`; `req.Host` override in executor.go line 521 |
| EXT-03 | 08-01, 08-02 | sslip.io URLs parse and resolve naturally via net/http | SATISFIED | No special URL handling required; `TestParse_Connectivity_SslipIO` confirms URL preserved; net/http resolves sslip.io via standard DNS |
| EXT-04 | 08-02 | Expected HTTP status code validated in external mode | SATISFIED | `checkExternalConnectivity` at executor.go lines 543–547 compares `resp.StatusCode == target.ExpectedStatusCode`; `TestCheckExternalConnectivity_StatusCodes` covers 6 code combinations |

No orphaned requirements — all 4 EXT requirements claimed in plan frontmatter and verified.

---

### Anti-Patterns Found

No anti-patterns detected across modified files (`types.go`, `loader.go`, `executor.go`, `loader_test.go`, `executor_test.go`):
- No TODO/FIXME/PLACEHOLDER comments
- No empty implementations or stub returns
- No console.log / fmt.Println debug artifacts
- All new functions have substantive implementations

---

### Human Verification Required

None. All behaviors are covered by deterministic unit tests using `httptest.NewServer`. No real cluster, DNS resolution, or UI interaction needed for this phase.

---

### Commit History

| Commit | Description |
|--------|-------------|
| `1d088bd` | feat(08-01): add Mode and HostHeader fields to connectivity types |
| `d6b1078` | feat(08-01): add parse-time mode validation + loader tests (EXT-01/02/03) |
| `14942d8` | feat(08-02): implement external connectivity mode via net/http |

---

## Summary

Phase 8 goal is fully achieved. The external HTTP connectivity validation mode is implemented end-to-end:

1. **Type layer** (`types.go`): `ConnectivitySpec.Mode` and `ConnectivityCheck.HostHeader` fields added with `omitempty` — existing challenges with no `mode` field are entirely unaffected.
2. **Parse layer** (`loader.go`): Incoherent specs (`mode: external` + `sourcePod`) are rejected at parse time with a clear error. Unknown mode values are also rejected. Empty mode passes (backwards compatible).
3. **Execution layer** (`executor.go`): `executeConnectivity` dispatches to `checkExternalConnectivityAll` when `spec.Mode == "external"`, which calls `checkExternalConnectivity` per target. This method uses `net/http` with `req.Host` override for virtual-host routing and `http.ErrUseLastResponse` to prevent automatic redirect following.
4. **Test coverage**: 18 new tests (5 loader + 13 executor) all passing. 578 total tests pass with 0 regressions.

All 4 requirements (EXT-01 through EXT-04) are satisfied.

---

_Verified: 2026-03-11T14:00:00Z_
_Verifier: Claude (gsd-verifier)_