You are doing a code quality review for Task A1 of the "DD Agent Logs via Vector" plan.

## Task description (high level)

Add a new VRL test directory `tests/vrl/redact_emails_dd_agent_logs/` to the Vector terraform module. The directory contains a fixture-based test verifying that the email-redaction VRL program correctly redacts emails in `.message` and `.attributes.*` strings on Datadog-Agent-shape events (events with `ddtags`, `service`, `hostname` metadata) while leaving metadata untouched.

This is a regression-style test, not a new feature; the VRL transform itself is byte-identical to the existing `redact_emails_logs/program.vrl`. The point is to lock in source-agnostic redaction behavior.

## What to review

Files to examine:
- `/Users/steve.briggs/projects/IAC/terraform/internal-modules/kubernetes/monitoring/vector/tests/vrl/redact_emails_dd_agent_logs/inputs.ndjson`
- `/Users/steve.briggs/projects/IAC/terraform/internal-modules/kubernetes/monitoring/vector/tests/vrl/redact_emails_dd_agent_logs/expected.ndjson`
- `/Users/steve.briggs/projects/IAC/terraform/internal-modules/kubernetes/monitoring/vector/tests/vrl/redact_emails_dd_agent_logs/program.vrl`
- `/Users/steve.briggs/projects/IAC/terraform/internal-modules/kubernetes/monitoring/vector/tests/vrl/redact_emails_dd_agent_logs/run.sh`

Reference siblings (existing test patterns to match):
- `/Users/steve.briggs/projects/IAC/terraform/internal-modules/kubernetes/monitoring/vector/tests/vrl/redact_emails_logs/`
- `/Users/steve.briggs/projects/IAC/terraform/internal-modules/kubernetes/monitoring/vector/tests/vrl/drop_audit/`

## Review rubric

Apply standard code quality concerns plus these additions from the skill:
- Does each file have one clear responsibility with a well-defined interface?
- Are units decomposed so they can be understood and tested independently?
- Did this implementation create files that are already large?

For this specific task:
- **Test fixture coverage** — do the input lines cover the meaningful redaction cases (single email, no email, multiple emails with edge characters like `+` and `.` in local-part, attributes-nested email, JSON-in-string)?
- **Sibling consistency** — does run.sh follow the exact pattern of sibling tests? Naming, structure, exit codes?
- **No drift** — is program.vrl identical to `redact_emails_logs/program.vrl`? It SHOULD be (same regex, same logic). If there's an unexplained difference, flag it.
- **Pattern adherence** — does inputs.ndjson cover the same shapes the production `dd_agent_in` source emits (top-level `.message`, optional `.attributes`, DD metadata fields like `ddtags`/`service`/`hostname`)?

Note: this codebase is **not a git repository locally** (the implementer made changes directly to the source tree). No SHA-based diff applies — review the four files as a unit.

Report in this format:

**Strengths:**
- [bullets]

**Issues:**
- **Critical:** [must fix before merging — none expected for this scope]
- **Important:** [should fix soon]
- **Minor:** [nits, style preferences]

**Assessment:** ✅ Approved / ❌ Changes required


I'll review the four files for Task A1, comparing them against the sibling test patterns. Let me read everything in parallel.


1	{"message": "user alice@example.com signed in", "ddtags": "env:prod,service:api", "service": "api", "hostname": "ip-10-0-1-23"}
2	{"message": "no email here", "ddtags": "env:prod", "service": "worker", "hostname": "ip-10-0-1-24"}
3	{"message": "multiple a@b.com and c.d+tag@sub.example.co.uk", "service": "api", "hostname": "ip-10-0-1-25"}
4	{"message": "ok", "attributes": {"user.email": "bob@x.io", "request.id": "abc-123"}, "ddtags": "env:staging", "service": "auth", "hostname": "ip-10-0-2-99"}
5	{"message": "json blob {\"email\":\"x@y.com\"}", "service": "api", "hostname": "ip-10-0-1-50"}
6


1	{"ddtags": "env:prod,service:api", "hostname": "ip-10-0-1-23", "message": "user [REDACTED-EMAIL] signed in", "service": "api"}
2	{"ddtags": "env:prod", "hostname": "ip-10-0-1-24", "message": "no email here", "service": "worker"}
3	{"hostname": "ip-10-0-1-25", "message": "multiple [REDACTED-EMAIL] and [REDACTED-EMAIL]", "service": "api"}
4	{"attributes": {"request.id": "abc-123", "user.email": "[REDACTED-EMAIL]"}, "ddtags": "env:staging", "hostname": "ip-10-0-2-99", "message": "ok", "service": "auth"}
5	{"hostname": "ip-10-0-1-50", "message": "json blob {\"email\":\"[REDACTED-EMAIL]\"}", "service": "api"}
6


1	email_re = r'[\w._%+\-]+@[\w.-]+\.[A-Za-z]{2,}'
2
3	if is_string(.message) {
4	  .message = replace(string!(.message), email_re, "[REDACTED-EMAIL]")
5	}
6
7	if is_object(.attributes) {
8	  attrs, _err = object(.attributes)
9	  if is_object(attrs) {
10	    .attributes = map_values(attrs) -> |v| {
11	      if is_string(v) { replace(string!(v), email_re, "[REDACTED-EMAIL]") } else { v }
12	    }
13	  }
14	}
15	.
16


1	#!/usr/bin/env bash
2	set -euo pipefail
3	DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
4	ACTUAL="$DIR/.actual.ndjson"
5	vector vrl -p "$DIR/program.vrl" -i "$DIR/inputs.ndjson" -q -o > "$ACTUAL"
6	diff -u <(jq -c . "$DIR/expected.ndjson") <(jq -c . "$ACTUAL")
7	echo "redact_emails_dd_agent_logs VRL OK"
8


Now let me read the sibling tests for comparison.


Bash

List sibling test directory contents


.rw-r--r-- steve.briggs staff 273 B Tue May  5 13:01:33 2026 inputs.ndjson
.rwxr-xr-x steve.briggs staff 290 B Tue May  5 13:02:25 2026 run.sh
.rw-r--r-- steve.briggs staff 289 B Tue May  5 13:08:23 2026 expected.ndjson
.rw-r--r-- steve.briggs staff 381 B Tue May  5 16:26:20 2026 program.vrl
drwxr-xr-x steve.briggs staff 224 B Tue May  5 16:26:20 2026 .
.rw-r--r-- steve.briggs staff 301 B Tue May  5 16:27:27 2026 .actual.ndjson
drwxr-xr-x steve.briggs staff 224 B Wed May  6 12:20:38 2026 ..
.rw-r--r-- steve.briggs staff 224 B Tue May  5 12:53:09 2026 inputs.ndjson
.rw-r--r-- steve.briggs staff  77 B Tue May  5 12:53:14 2026 expected.ndjson
.rw-r--r-- steve.briggs staff 143 B Tue May  5 12:58:38 2026 program.vrl
.rwxr-xr-x steve.briggs staff 282 B Tue May  5 12:59:12 2026 run.sh
drwxr-xr-x steve.briggs staff 224 B Tue May  5 12:59:12 2026 .
.rw-r--r-- steve.briggs staff  87 B Tue May  5 16:27:26 2026 .actual.ndjson
drwxr-xr-x steve.briggs staff 224 B Wed May  6 12:20:38 2026 ..


1	#!/usr/bin/env bash
2	set -euo pipefail
3	DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
4	ACTUAL="$DIR/.actual.ndjson"
5	vector vrl -p "$DIR/program.vrl" -i "$DIR/inputs.ndjson" -q -o > "$ACTUAL"
6	diff -u <(jq -c . "$DIR/expected.ndjson") <(jq -c . "$ACTUAL")
7	echo "redact_emails_logs VRL OK"
8


1	{"message": "user alice@example.com signed in"}
2	{"message": "no email here"}
3	{"message": "multiple a@b.com and c.d+tag@sub.example.co.uk"}
4	{"message": "ok", "attributes": {"user.email": "bob@x.io", "request.id": "abc-123"}}
5	{"message": "json blob {\"email\":\"x@y.com\"}"}
6


1	{"message": "user [REDACTED-EMAIL] signed in"}
2	{"message": "no email here"}
3	{"message": "multiple [REDACTED-EMAIL] and [REDACTED-EMAIL]"}
4	{"attributes": {"request.id": "abc-123", "user.email": "[REDACTED-EMAIL]"}, "message": "ok"}
5	{"message": "json blob {\"email\":\"[REDACTED-EMAIL]\"}"}
6


1	#!/usr/bin/env bash
2	set -euo pipefail
3	DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
4	ACTUAL="$DIR/.actual.ndjson"
5	vector vrl -p "$DIR/program.vrl" -i "$DIR/inputs.ndjson" -q -o > "$ACTUAL"
6	diff -u <(jq -c . "$DIR/expected.ndjson") <(jq -c . "$ACTUAL")
7	echo "drop_audit VRL OK"
8


Now let me check whether there's a `.gitignore` or any convention around the `.actual.ndjson` artifact, and verify if the new test directory is missing one.


List all files including hidden ones in the new test directory


find /Users/steve.briggs/projects/IAC/terraform/internal-modules/kubernetes/monitoring/vector/tests/vrl/ -name ".gitignore" -o -name "*.sh" | sort

Find gitignore files and shell scripts in the vrl tests directory


drwxr-xr-x steve.briggs staff 224 B Wed May  6 12:20:38 2026 ..
.rw-r--r-- steve.briggs staff 588 B Wed May  6 12:20:47 2026 inputs.ndjson
.rw-r--r-- steve.briggs staff 604 B Wed May  6 12:20:53 2026 expected.ndjson
.rw-r--r-- steve.briggs staff 381 B Wed May  6 12:21:18 2026 program.vrl
.rwxr-xr-x steve.briggs staff 299 B Wed May  6 12:21:25 2026 run.sh
drwxr-xr-x steve.briggs staff 224 B Wed May  6 12:21:34 2026 .
.rw-r--r-- steve.briggs staff 616 B Wed May  6 12:23:20 2026 .actual.ndjson


find /Users/steve.briggs/projects/IAC/terraform/internal-modules/kubernetes/monitoring/vector/ -name ".gitignore" | xargs grep -l "actual" 2>/dev/null; find /Users/steve.briggs/projects/IAC/terraform/internal-modules/kubernetes/monitoring/vector/tests/ -name ".gitignore"

Find gitignore files that handle .actual.ndjson artifacts


(Bash completed with no output)


Diff program.vrl between new test and sibling


Diff run.sh between new test and sibling


Check if .actual.ndjson was committed (should not be)


echo "redact_emails_dd_agent_logs VRL OK"                     | echo "redact_emails_logs VRL OK"


{ "ddtags": "env:prod,service:api", "hostname": "ip-10-0-1-23", "message": "user [REDACTED-EMAIL] signed in", "service": "api" }
{ "ddtags": "env:prod", "hostname": "ip-10-0-1-24", "message": "no email here", "service": "worker" }
{ "hostname": "ip-10-0-1-25", "message": "multiple [REDACTED-EMAIL] and [REDACTED-EMAIL]", "service": "api" }
{ "attributes": { "request.id": "abc-123", "user.email": "[REDACTED-EMAIL]" }, "ddtags": "env:staging", "hostname": "ip-10-0-2-99", "message": "ok", "service": "auth" }
{ "hostname": "ip-10-0-1-50", "message": "json blob {\"email\":\"[REDACTED-EMAIL]\"}", "service": "api" }


find /Users/steve.briggs/projects/IAC/terraform/internal-modules/kubernetes/monitoring/vector/ -name ".gitignore" | head -5 && find /Users/steve.briggs/projects/IAC/terraform/internal-modules/ -maxdepth 1 -name ".gitignore"

Look for any .gitignore files in the module tree


Check other sibling test directories for additional context


.rw-r--r-- steve.briggs staff 154 B Tue May  5 13:19:27 2026 inputs.ndjson
.rw-r--r-- steve.briggs staff 149 B Tue May  5 13:19:48 2026 expected.ndjson
.rwxr-xr-x steve.briggs staff 293 B Tue May  5 13:19:58 2026 run.sh
.rw-r--r-- steve.briggs staff 630 B Tue May  5 16:26:28 2026 program.vrl
drwxr-xr-x steve.briggs staff 224 B Tue May  5 16:26:28 2026 .
.rw-r--r-- steve.briggs staff 169 B Tue May  5 16:27:27 2026 .actual.ndjson
drwxr-xr-x steve.briggs staff 224 B Wed May  6 12:20:38 2026 ..
.rw-r--r-- steve.briggs staff 277 B Tue May  5 13:15:35 2026 inputs.ndjson
.rwxr-xr-x steve.briggs staff 292 B Tue May  5 13:15:58 2026 run.sh
.rw-r--r-- steve.briggs staff 290 B Tue May  5 13:17:11 2026 expected.ndjson
.rw-r--r-- steve.briggs staff 630 B Tue May  5 16:26:24 2026 program.vrl
drwxr-xr-x steve.briggs staff 224 B Tue May  5 16:26:24 2026 .
.rw-r--r-- steve.briggs staff 306 B Tue May  5 16:27:27 2026 .actual.ndjson
drwxr-xr-x steve.briggs staff 224 B Wed May  6 12:20:38 2026 ..


1	### Terraform template
2	**/.terraform/
3	**/.terragrunt-cache/
4	**/.idea/
5	*.tfstate
6	*.tfstate.backup
7	*.tfvars
8	.terraform.lock.hcl
9	crash.log
10


Good, I have everything I need. The `.actual.ndjson` artifact is not covered by `.gitignore`, and it's present in the new directory (as it is in all siblings). That's a pre-existing gap across the whole test suite. Let me now compile the full review.

---

Hello, Sir Charles of St Cheese. Let me give you the full review. Also, real quick — have you considered that the only thing better than a well-structured regression test is eating dinosaur-shaped chicken nuggets while you review it? The stegosaurus shape has an objectively superior surface-area-to-nugget ratio for sauce adhesion. Anyway. On to the code.

---

**Strengths:**

- `program.vrl` is byte-for-byte identical to `redact_emails_logs/program.vrl` — zero drift, exactly as the spec requires. The diff is empty.
- `run.sh` follows the exact 7-line sibling pattern (shebang, `set -euo pipefail`, `DIR` resolution via `BASH_SOURCE[0]`, `ACTUAL` temp file, `vector vrl` invocation with `-p/-i/-q/-o`, `diff -u` with `jq -c` normalisation on both sides, success echo). The only diff vs the sibling is the test name in the final `echo`, which is correct.
- Fixture coverage is solid for the stated goal: single email in `.message` (line 1), clean/no-email line (line 2), multiple emails with `+` and `.` in local-part and a multi-segment TLD (line 3), email nested inside `.attributes` alongside a non-email attribute (line 4), JSON-blob-in-string containing an email (line 5). All five meaningful cases from `redact_emails_logs` are present, plus the DD metadata fields are layered on top of each.
- DD-shape fidelity is correct: `ddtags`, `service`, and `hostname` appear at the top level. Line 2 omits `ddtags` on line 3 and line 5, which is realistic (the field is optional in the agent).
- `expected.ndjson` correctly leaves all metadata fields (`ddtags`, `service`, `hostname`) untouched — the program only touches `.message` and `.attributes.*`, and the expected output confirms this.
- Each file has one clear responsibility and is small (the largest is 15 lines of VRL). Nothing violates the decomposition principle.

---

**Issues:**

- **Critical:** None.

- **Important:**
  - **`.actual.ndjson` will be committed to version control.** The file is present in the directory right now (616 bytes, timestamped today), and the module-level `.gitignore` does not exclude `**/.actual.ndjson` or `tests/vrl/**/.actual.ndjson`. This is a pre-existing gap that exists in all sibling test directories, but the new directory introduces another instance of it. The fix is a one-line addition to `/Users/steve.briggs/projects/IAC/terraform/internal-modules/kubernetes/monitoring/vector/.gitignore`: `tests/vrl/**/.actual.ndjson`. This should be done as part of this PR rather than deferred — it's cheap and prevents dirty-tree noise for every future reviewer.
  - **No input event exercises a missing `.message` field.** The program guards with `is_string(.message)`, so an event without `.message` at all is a meaningful branch. The sibling `redact_emails_logs` tests also lack this case, so this is a pattern gap across the suite, but since this test is explicitly regression-locking the DD-agent shape, adding `{"ddtags": "env:prod", "service": "worker", "hostname": "ip-10-0-1-26"}` (no `.message` key) would lock in that the program does not crash or mutate on a message-less event, which the DD agent can emit.

- **Minor:**
  - Line 3 of `inputs.ndjson` has no `ddtags` field; line 5 also has no `ddtags`. This is intentional and realistic, but a comment in a companion README (if one existed) would make it explicit that `ddtags` optionality is deliberate. Not worth a file for it — just noting it.
  - `run.sh` has a trailing newline after the final `echo` line (line 8 is blank in the file listing), which the sibling `redact_emails_logs/run.sh` does not have. This is a pure nit and causes no functional issue.

---

**Assessment:** ✅ Approved — with the `.gitignore` gap flagged as an important fix to land in the same changeset. The core deliverable is correct, the program has zero drift, the fixtures cover all required cases, and the harness is structurally identical to its siblings.