Add Cloudflare Email Worker: Discord notify + mail forward - #1
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Implement an Email Worker that, per incoming message, forwards it to
{username}@FORWARD_EMAIL_DOMAIN and posts a Discord embed to the webhook
mapped to the recipient username.
- src/index.ts: email() handler (non-awaited forward, lazily cached
DISCORD_WEBHOOK_MAP parse, skip notify for unmapped users, errors logged
and swallowed so forwarding is never blocked).
- src/email.ts: username extraction, postal-mime body parse, HTML->text.
- src/discord.ts: embed formatting with Discord limit trimming.
- .env.yaml as single config source with gen:dev-vars (local .dev.vars) and
set:secrets (wrangler secret bulk) scripts; secret files git-ignored.
- Tooling: bun, @cloudflare/vite-plugin, vitest + @cloudflare/vitest-pool-workers.
- 21 tests covering helpers and handler flow.
Claude-Session: https://claude.ai/code/session_012cEF1ARSdtXP8iWwDPn6Ly
Quality cleanups from a review pass (no behavior change intended): - discord.ts: drop BODY_LIMIT double-truncation; truncate the body once against the real EMBED_DESCRIPTION_LIMIT. - index.ts: key the webhook-map cache on the raw secret so it re-parses on change; removes the test-only resetWebhookMapCache export while still parsing once per instance in production. - email.ts: fold the six HTML entity-decode passes into a single regex pass; flatten the nested from-address ternary. - test/fixtures.ts: shared buildMime/mimeStream helpers, reused by the email and handler tests instead of duplicated MIME strings. - gen-dev-vars.ts: serialize secrets generically so new keys propagate. Claude-Session: https://claude.ai/code/session_012cEF1ARSdtXP8iWwDPn6Ly
Replace the hand-written .gitignore with GitHub's official Node template and append the Cloudflare Worker specifics (wrangler, .dev.vars, .env.yaml, generated worker types), including a negation to keep .env.yaml.example tracked since the template's `.env.*` rule would otherwise ignore it. Claude-Session: https://claude.ai/code/session_012cEF1ARSdtXP8iWwDPn6Ly
Supply-chain hardening: refuse npm versions published less than 3 days (259200s) ago, so a compromised fresh release has time to be caught and yanked before it can be installed. Existing pinned lockfile versions are unaffected; the cooldown applies to future adds/updates. Claude-Session: https://claude.ai/code/session_012cEF1ARSdtXP8iWwDPn6Ly
- Update the only outdated dependencies to latest majors: typescript 5.9 -> 7 and @types/node 22 -> 26. All other deps were already at latest. Typecheck, the 21 tests, and the build stay green. The 3-day minimumReleaseAge cooldown from bunfig.toml applies to these installs. - Add mise.toml pinning bun 1.3.11 and node 24 so contributors get a consistent toolchain; ignore mise local override files. - Document the mise + cooldown workflow in the README. Claude-Session: https://claude.ai/code/session_012cEF1ARSdtXP8iWwDPn6Ly
- Rename the `cf-typegen` script to `gen:cf-types` so all generators share the `gen:` prefix. - Add a `gen` script that runs every generator (gen:cf-types + gen:dev-vars). - Document both in the README. Claude-Session: https://claude.ai/code/session_012cEF1ARSdtXP8iWwDPn6Ly
Drop the Node template's entries for tools/frameworks this project doesn't use (Grunt, Bower, Snowpack, Next/Nuxt/Gatsby/vuepress/vitepress/SvelteKit/ Docusaurus, Serverless, FuseBox, DynamoDB, Firebase, pnpm/yarn-v3, npm/parcel caches, node-gyp, diagnostic reports, pids). Keep only what's relevant to bun/vite/vitest/wrangler/TypeScript plus the Cloudflare Worker specifics. Claude-Session: https://claude.ai/code/session_012cEF1ARSdtXP8iWwDPn6Ly
Production secret upload isn't needed for now. Drop the set:secrets script and its scripts/set-secrets.ts; keep gen:dev-vars (local) and the shared load-config.ts. README now points to `wrangler secret put` / the dashboard for setting production secrets. Claude-Session: https://claude.ai/code/session_012cEF1ARSdtXP8iWwDPn6Ly
- Move tests out of test/ to src/*.test.ts (email/discord/index), colocated with the code they cover; move the MIME helpers to src/test-fixtures.ts. - Express each spec through the test name and drop explanatory comments. - Use it.each table-driven cases where the inputs/outputs are plain data (extractUsername, htmlToText, parseWebhookMap, embed limits); keep mock-driven handler cases as individual tests. - Update tsconfig include to drop the removed test/ dir. Claude-Session: https://claude.ai/code/session_012cEF1ARSdtXP8iWwDPn6Ly
Shorten the header/field comments to one-liners; the full explanation already lives in the README. Claude-Session: https://claude.ai/code/session_012cEF1ARSdtXP8iWwDPn6Ly
Fold the 6-step handler walkthrough into a short paragraph, drop the duplicated .env.yaml sample (it lives in .env.yaml.example), and tighten Configuration and Development into compact command blocks. Claude-Session: https://claude.ai/code/session_012cEF1ARSdtXP8iWwDPn6Ly
- Drop source comments that merely restate behavior already pinned by tests (extractUsername/parseEmail/htmlToText/buildDiscordPayload/notifyDiscord/ parseWebhookMap and the handler's skip/error-swallow steps); keep the non-obvious rationale (webhook-map cache keying, forward concurrency). - Move the MIME/mock helpers and fixtures to src/test/fixtures.ts (including makeMessage/makeEnv) so the colocated src/*.test.ts files stay short. Claude-Session: https://claude.ai/code/session_012cEF1ARSdtXP8iWwDPn6Ly
Move the primary entry points to the top of each file and push supporting helpers below them, relying on function hoisting: the email() handler now leads src/index.ts (parseWebhookMap / webhook-map cache follow), and notifyDiscord leads src/discord.ts (buildDiscordPayload / truncate / limit constants follow). Claude-Session: https://claude.ai/code/session_012cEF1ARSdtXP8iWwDPn6Ly
Restructure each test file into three describe groups — positive (happy path), semi-positive (alternative/boundary but valid), negative (invalid/error) — and distribute the existing cases accordingly. Claude-Session: https://claude.ai/code/session_012cEF1ARSdtXP8iWwDPn6Ly
Group tests by function first, then by case type: each function gets a describe, containing positive / semi-positive / negative sub-describes with the relevant cases. Claude-Session: https://claude.ai/code/session_012cEF1ARSdtXP8iWwDPn6Ly
rin2yh
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Jul 14, 2026
Reconcile with the rebased PR #1 base (test helpers moved to src/test/fixtures.ts, comments trimmed, README condensed). Resolutions: - discord.ts keeps the concrete DiscordWebhookPayload return type on top of PR #1's trimmed style. - oxlint unknown-override path updated to src/test/fixtures.ts. - README merged: kept PR #1's condensed prose, kept the CI/lint/format additions. - Reformatted with oxfmt so `oxfmt --check` stays clean. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_014GKWrRcDKcg13Xqv5qrr1V
buildDiscordPayload now returns DiscordWebhookPayload / DiscordEmbed (exported) instead of unknown, so the test asserts against the real production type rather than a locally duplicated Embed interface that could drift from the payload. Claude-Session: https://claude.ai/code/session_012cEF1ARSdtXP8iWwDPn6Ly
Move the module-level constants above the type definitions so limits and lookup tables are visible up front: the Discord embed limits in src/discord.ts and the HTML entity table in src/email.ts now lead their files. Claude-Session: https://claude.ai/code/session_012cEF1ARSdtXP8iWwDPn6Ly
positive = specified behaviour (including fallbacks and limit trimming); semi-positive = validation that rejects out-of-contract input; negative = abnormal external failures. Move the spec-driven fallback/trimming cases into positive, keep only the invalid-config validation in semi-positive, and leave the webhook error-response case as negative. Claude-Session: https://claude.ai/code/session_012cEF1ARSdtXP8iWwDPn6Ly
The field-based it.each branched on the row (embedOf(email)[field]), which doesn't fit a data table cleanly. Replace it with two plain tests for the title and description limits. Claude-Session: https://claude.ai/code/session_012cEF1ARSdtXP8iWwDPn6Ly
Real mail always has a sender (From is required and the envelope MAIL FROM is always present), so a header-less message asserting "(unknown sender)" was unrealistic. Test the case that actually occurs — a message with a sender but no Subject — asserting the "(no subject)" fallback while the sender is extracted. The defensive sender fallback stays in code for type/crash safety. Claude-Session: https://claude.ai/code/session_012cEF1ARSdtXP8iWwDPn6Ly
A code-audit subagent judged these guards unreachable given the runtime: - extractUsername: message.to is always a non-empty bare envelope address, so the empty-string guard, the "Name <addr>" angle-bracket parsing, and the no-"@" fallback can never fire. Reduce to slicing the local part. - truncate: all call sites use limits (256/4096/1024) far larger than the marker length and only run when value exceeds the limit, so the Math.max(0, ) clamp never fires. Guards it judged JUSTIFIED (postal-mime optional types, secret validation, external HTTP body read, empty-body/no-subject fallbacks) are kept. Drop the now-unreachable extractUsername test rows. Claude-Session: https://claude.ai/code/session_012cEF1ARSdtXP8iWwDPn6Ly
Rather than silently slicing a malformed value, make the "input is an email address" invariant an explicit contract: throw if there is no "@". The case can't occur for a real message.to, so this is a loud tripwire, not graceful handling. Add a test documenting the contract. Claude-Session: https://claude.ai/code/session_012cEF1ARSdtXP8iWwDPn6Ly
Replace the per-field assertions and the separate limit tests with one it.each that deep-equals the whole embed against an expected value. The over-long rows encode the exact truncated string, so they cover both the marker and the length limit in a single equality. Claude-Session: https://claude.ai/code/session_012cEF1ARSdtXP8iWwDPn6Ly
Make parseWebhookMap, htmlToText, buildDiscordPayload and the Discord payload types private again, and test them through the public boundary instead: - HTML-to-text via parseEmail (an HTML-only message), - the Discord embed via notifyDiscord (asserting the posted request body), - webhook-map validation via the handler (invalid/non-object config forwards without notifying). Only genuinely public surface stays exported (extractUsername, parseEmail, ParsedEmail, notifyDiscord, Env, the worker). Claude-Session: https://claude.ai/code/session_012cEF1ARSdtXP8iWwDPn6Ly
- email.ts: match HTML entities with a generic `&(#?\w+);` regex + map lookup instead of restating the map's keys in the alternation (single source). - test/fixtures.ts: build makeMessage's MIME from the passed `to` so the raw To header and message.to agree; add shared spyFetchOk/spyFetchError helpers. - index/discord tests: use the shared fetch-spy helpers. Skipped: exporting the embed limits/marker for the test (keeps the no- test-only-export policy), dropping the webhook-map cache (the "parse once per instance" requirement), and merging WorkerSecrets into Env (distinct concerns). Claude-Session: https://claude.ai/code/session_012cEF1ARSdtXP8iWwDPn6Ly
rin2yh
pushed a commit
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Jul 14, 2026
Take PR #1's refactored source and tests as canonical (typed Discord payload, private internals, reorganized tests, spyFetch helpers). Re-apply this branch's CI policy on top: - src/index.ts: per-line disable for the JSON.parse boundary `unknown`. - src/test/fixtures.ts: type the message mock instead of `as unknown as`. - src/discord.test.ts: per-line disables for the two genuine test-only `unknown` uses (parsed JSON return, table expected value). Reformatted with oxfmt; oxlint/typecheck/tests all pass. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_014GKWrRcDKcg13Xqv5qrr1V
rin2yh
marked this pull request as ready for review
July 14, 2026 09:31
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概要
メールをユーザー名対応の Discord Webhook に通知しつつ、別のメールサーバーへ転送する Cloudflare Email Worker。
{username}@your-domain（例user1@gophercon.jp）宛のメールを処理{username}@FORWARD_EMAIL_DOMAINへ転送{username}対応の Webhook へ embed で通知（未登録は転送のみ・エラーなし）postal-mimeの1つのみ設計判断
postal-mimemessage.raw（生MIME）しか手段がなく、multipart / エンコーディング / 文字コード / HTML→text を自前実装するのは困難mise.tomlで bun / node をピンし、環境差をなくすbunfig.tomlのminimumReleaseAge（3日）レビュー観点
内部品質
src/index.ts/ Discord 整形src/discord.ts/ メール処理src/email.ts外部品質
DISCORD_WEBHOOK_MAPが不正なJSON の場合補足