# chanora_diagnostics

Application diagnostics: log redaction, in-memory log capture, and user-initiated diagnostic export. Per DEC-016, export is **user-initiated only**; there is no automatic upload.

## Architecture

### Redaction policy

`Redactor` applies the production policy (REDACT-TC-001..010):

1. Known-secret registry — substring match → `[REDACTED]`
2. `$HOME` prefix → `[home]`
3. IPv4 addresses → `[ip]`
4. IPv6 addresses → `[ip]`
5. Email-shaped strings → `[email]`
6. Long opaque tokens (base64 ≥32 chars, ≥75% alnum) → `[token]`

### PTT sanitiser

`PttSanitizer<L>` — a `tracing-subscriber` Layer decorator that drops any record containing field names from the banned list (`key_code`, `scan_code`, `virtual_key`, `keysym`, etc.) per DEC-027 / REDACT-PTT-001..006. Allocation-free on the success path.

### Log capture

`InMemoryLogSink` — bounded ring buffer that passes every line through the redactor before storing. Capacity differs by build: 4096 lines (debug), 256 lines (release) per SRS-122.

### Event recorder

`ProtocolEventRecorder` — ring buffer of protocol-level events (connect, disconnect, reconnect, snapshot changes, channel joins) for diagnostic export and state-sync replay verification (SRS-097/098).

### Export

`DiagnosticExport` — serialisable bundle containing:
- Client metadata (version, platform)
- Redacted recent logs
- Known-secret count (values never exported)
- Optional Android audio diagnostics YAML
- Optional network diagnostics summary
- Protocol event trace

## Public API Summary

### Types

| Type | Role |
|---|---|
| `Redactor` | Production redaction policy (cheap to clone) |
| `KnownSecretRegistry` | Cross-spike secret registry for defence in depth (SS-AUD-003) |
| `InMemoryLogSink` | Bounded ring buffer of redacted log lines |
| `RedactingLogLayer` | `tracing-subscriber` Layer feeding `InMemoryLogSink` |
| `PttSanitizer<L>` | Layer decorator dropping PTT-sensitive records |
| `DiagnosticExport` | User-facing export bundle |
| `ProtocolEventRecorder` | Protocol event ring buffer (SRS-097) |
| `DiagnosticsError` | Export, Io |
| `REDACTION_MARKER` | `"[REDACTED]"` |

### Key methods

**Redactor:**
- `with_default_policy()` / `with_secrets(registry)` — construct
- `redact(s)` → `String` — apply policy
- `secrets()` → `&KnownSecretRegistry` — register secrets

**KnownSecretRegistry:**
- `register(secret)` — add a known-secret value (≥4 chars)
- `contains_substr(haystack)` → `bool` — substring check

**InMemoryLogSink:**
- `new(capacity, redactor)` — construct
- `push(raw)` — redact and store a line
- `snapshot()` → `Vec<String>` — current buffer contents

**DiagnosticExport:**
- `from_sink(sink, metadata)` — build from log sink
- `with_android_audio(yaml)` / `with_network_info(info)` / `with_protocol_events(events)` — attach optional sections
- `to_text()` → `String` — render as multi-line plaintext

**ProtocolEventRecorder:**
- `new(capacity)` — construct
- `record_connected(server_name)` / `record_disconnected(reason)` / `record_reconnecting(attempt, delay)`
- `drain()` → `Vec<String>` / `snapshot()` → `Vec<String>`