feat(reddit): OAuth2 credential and 5 authenticated operations (closes #21)

[jackulau]

Closes #21.

Summary

Extends the existing redditMonitorNode (unauthenticated public search.json scraping) with five authenticated Reddit operations and the OAuth2 credential they share. Mirrors the twitter-extended pattern already established in packages/nodes/src/integrations/social/ — one file per operation, one shared *-client.ts auth helper, one consolidated *-extended.test.ts.

Acceptance Criteria

• OAuth2 credential definition
• All 5 new operations
• Zod schemas
• Unit tests

What's in the diff

Credential

redditCredential defined in packages/nodes/src/integrations/social/credentials.ts via defineOAuth2Credential.

Field	Value
name	reddit
type	oauth2 (non-PKCE)
authorizationUrl	https://www.reddit.com/api/v1/authorize
tokenUrl	https://www.reddit.com/api/v1/access_token
scopes	identity, submit, read, history, mysubreddits
Schema	clientId, clientSecret, accessToken, refreshToken?, expiresAt?

NodeCredentials in @jam-nodes/core also gains a typed reddit entry so nodes can read context.credentials.reddit.accessToken without casts — matching the existing twitter / slack / googleSheets entries.

Operations

Each operation is a standalone file under packages/nodes/src/integrations/social/:

Node	Endpoint	Notes
redditCreatePostNode	POST /api/submit	kind: 'self' | 'link' | 'image' with .superRefine guard requiring text for self and url for link/image. Form-encoded body via URLSearchParams. Returns postId, postName (t3_… fullname), url, synthesized permalink, title, subreddit.
redditCreateCommentNode	POST /api/comment	Normalizes thing_id — if caller passes raw postId (e.g. abc123), prepends t3_; if already prefixed (t3_abc123 / t1_abc123), passes through unchanged.
redditReplyToCommentNode	POST /api/comment	Same pattern with t1_ prefix. Kept as a separate node for API clarity since the target thing_id type differs.
redditSearchPostsNode	GET /search or GET /r/<sr>/search	Schema defaults: sort='new', time='day', limit=25 (max 100). Sends restrict_sr=on when a subreddit is provided. Returns normalized post list, pagination after token, and resultCount.
redditGetPostCommentsNode	GET /comments/<postId>	Strips any t3_ prefix from the input id. Iterative BFS flatten of nested comment trees (not recursive — verified safe at 50-level depth in tests). Skips kind: 'more' stubs and gracefully handles replies: "" leaves. Emits parentId and depth per comment.

Shared client (reddit-client.ts)

• redditRequest<T>(context, path, init) wraps fetchWithRetry (which already handles 429 + Retry-After, 5xx backoff, timeouts, and throws on 401/403) and injects:
  • Authorization: Bearer <accessToken>
  • User-Agent: jam-nodes/1.0 — Reddit rejects unrecognized / default-fetch UAs
• getRedditAccessToken(context) returns the token or null for the per-node guard clause.
• formatRedditErrors(errors) flattens Reddit's [code, message, field] error tuples into readable strings, since /api/submit and /api/comment return 200 OK with non-empty json.errors for logical failures.

Architectural alignment

• Nodes stay pure — no retry/rate-limit/cache logic inside. Cross-cutting concerns remain in the execution engine per the project's stated architecture (see CLAUDE.md, issue feat: add execution engine with configurable retry, caching, and timeout #37, PR feat: add an execution engine with configurable retry, caching, and timeout #39).
• No z.any() or as any — every input and output has an explicit Zod schema.
• No token refresh inside nodes. If the host passes a stale accessToken, fetchWithRetry surfaces the 401 directly and the caller handles refresh.

Test plan

Single consolidated file: packages/nodes/src/integrations/social/reddit-extended.test.ts (33 tests, all passing). Uses the vi.stubGlobal('fetch', ...) pattern from twitter-extended.test.ts.

Coverage:

• Credential metadata: scopes exact match, authorization/token URLs, schema accept/reject.
• Missing-token guard for each of the 5 nodes.
• Happy path for each node with a mocked Reddit response shape.
• Form-encoded body assertions (URL encoding of &, Content-Type header).
• thing_id normalization: four cases covering raw + prefixed input for both comment nodes.
• Reddit json.errors non-empty → node returns success: false with the formatted error for all three write nodes.
• Search-posts: all-subreddits vs restricted, schema defaults, schema rejection of limit > 100, normalized post shape, empty result set.
• Comment flatten: simple, multi-level with depth, kind: 'more' skipped, empty listing, 50-level deep chain (stack-safety).

Verification

Run from the packages/nodes directory:

npx vitest run src/integrations/social/reddit-extended.test.ts
# 33 tests, 33 pass
npm test                     # full suite: 224/228 pass
                             # (the 4 failures are pre-existing on main —
                             # webhook-trigger x3, apify x1 — unrelated)

• packages/core npm run typecheck passes.
• packages/nodes npm run typecheck surfaces the same 18 pre-existing errors as main (apify / google-sheets / slack), zero new from this change.
• packages/core npm run build passes.