Implement server-side ad slot templates with PBS and APS auction#680
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Implement server-side ad slot templates with PBS and APS auction#680
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Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
- Incorporate all review feedback (aram356 + jevansnyc): cache contract, consent/GDPR gating, async restructuring detail, CreativeOpportunityFormat schema, glob pattern fix, XSS escaping, win notifications, APS params, timeout config key, defineSlot fix, gpt.rs ownership, KV migration path, Phase 2 sketch - Fix Prettier formatting (format-docs CI) - Add implementation plan (12 tasks, TDD, ordered by dependency)
- Incorporate all review feedback (aram356 + jevansnyc): cache contract, consent/GDPR gating, async restructuring detail, CreativeOpportunityFormat schema, glob pattern fix, XSS escaping, win notifications, APS params, timeout config key, defineSlot fix, gpt.rs ownership, KV migration path, Phase 2 sketch - Fix Prettier formatting (format-docs CI) - Add implementation plan (12 tasks, TDD, ordered by dependency)
Replace the head-injected __ts_bids design with a server-cached bid delivery model fetched by the client via a new /ts-bids endpoint. The auction never blocks page rendering — </head> flushes immediately, body parses without waiting for bids, and the client fetches bids in parallel with content paint. Key changes: - §2 Goal: bid delivery decoupled from page rendering; FCP unchanged from no-TS baseline - §4.3 Auction Trigger: drop buffered/streaming dichotomy; single mode forces chunked encoding on all origins (WordPress, NextJS, etc.) - §4.4 Head Injection: only __ts_ad_slots and __ts_request_id injected at <head> open; bid results moved to /ts-bids endpoint - §4.6 Client Residual: __tsAdInit defines slots immediately, fetches bids via /ts-bids, applies targeting and fires refresh() after resolve - §4.7 (new) Caching Behavior: explicit cacheability table for HTML, JS, CSS, tsjs bundle, bid results; Fastly edge HTTP cache leveraged for origin HTML - §5 Request-Time Sequence: full mermaid diagram covering content + creative + burl flow with cache-hit and cache-miss branches; separate text sequences for cache-hit (~80ms FCP, ~900ms ad-visible) and cache-miss (~250ms FCP, ~1,050ms ad-visible) - §6 Performance Summary: cache-hit and cache-miss columns; FCP added as a tracked metric - §7 Implementation Scope: add bid_cache.rs, /ts-bids endpoint, force chunked encoding step - §8 Edge Cases: origin-agnostic entries; new entries for /ts-bids 404 and client-never-fetches-/ts-bids Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Pivot from the /ts-bids fetch endpoint + in-process bid_cache design to
inline __ts_bids injection before </body>. The earlier design relied on
shared state that doesn't reliably survive Fastly Compute's per-request Wasm
isolate model — body injection achieves the same FCP property in a single
response with no shared-state requirement.
Key changes:
- §4.3: replace /ts-bids long-poll with bounded </body> hold tied to
A_deadline. Body content above </body> paints first; close-tag held
until auction completes or A_deadline fires (graceful __ts_bids = {}
fallback).
- §4.3: add auction-eligibility gating (consent, bot UA, prefetch hints,
HEAD method, slot match) so auctions fire on real first-page-load
impressions only.
- §4.4: replace __ts_request_id + /ts-bids machinery with two inline
<script> blocks — __ts_ad_slots at <head> open, __ts_bids before
</body> via lol_html el.on_end_tag().
- §4.5: move both nurl and burl to client-side firing from
slotRenderEnded after hb_adid match. Server-side firing rejected to
avoid billing inflation on bids that never render.
- §4.6: replace fetch+Promise pattern with synchronous __ts_bids read.
Add lazy slim-Prebid loader (post-window.load) for scroll/refresh
auctions and Phase B identity warm-up. Add ts_initial=1 slot-ownership
sentinel.
- §4.7: switch Cache-Control from private, no-store to private,
max-age=0 to preserve browser BFCache eligibility while still
preventing intermediate-cache leaks.
- §4.8 (new): document the EC/KV identity model as load-bearing auction
input — Phase A retrieval at request time, Phase B post-render
enrichment via slim-Prebid userID modules. Add bare-EC first-impression
caveat and auction_eid_count metric. Note federated-consortium
passphrase property and clickstream-compounding speed win.
- §5: update mermaid + cache-hit/miss timelines for bounded body hold;
ad-visible converges to ~870ms (hit) / ~1,020ms (miss).
- §6: drop /ts-bids RTT row; add DCL row; add clickstream-compounding,
TS-overhead, identity-coverage, and confidence-interval framing.
- §7: drop bid_cache.rs and /ts-bids endpoint from scope; add
auction-eligibility gating and slim-Prebid bundle build target. Add
explicit "Deleted" subsection.
- §8: drop /ts-bids edge cases; add SPA/pushState, bare-EC, bot/prefetch,
HEAD, BFCache restoration cases.
- §9.6: server-side GAM downgraded from "Phase 2 commitment" to
aspirational and contingent on Google agreement. §9.8 (slim-Prebid
bundle composition), §9.9 (Privacy Sandbox), §9.10 (per-bidder consent)
added as follow-ups.
Implementation plan at docs/superpowers/plans/2026-04-30-server-side-ad-templates.md
is now stale relative to this spec; needs regenerating before code lands.
…ities.toml Adds the creative_opportunities field to Settings struct to deserialize configuration for the server-side ad auction feature. Includes build.rs stubs for types required during build-time configuration validation. Creates creative-opportunities.toml with example slot configuration and updates trusted-server.toml with the [creative_opportunities] section defining GAM network ID, auction timeout, and price granularity settings. Tests pass with proper TOML parsing of the creative_opportunities section.
…ared auction state
- Add `ad_slots_script: Option<String>` and `ad_bids_state: Arc<RwLock<Option<String>>>` fields to `HtmlProcessorConfig`
- Update `from_settings` to initialize both new fields with safe defaults
- Prepend `ad_slots_script` inside the existing `<head>` handler before integration inserts
- Add `element!("body", ...)` handler that uses `end_tag_handlers()` to inject `__ts_bids` before `</body>`; falls back to empty `{}` when auction state is `None`
- Add `IntegrationRegistry::empty_for_tests()` test helper
- Add three new tests covering all injection paths
…gibility gates; max-age=0 - Make handle_publisher_request async; add orchestrator and slots_file params - Dispatch origin request with send_async before running auction in parallel - Gate auction on GET, no prefetch, no bot, matched slots, TCF purpose-1 consent - Run server-side auction and write bucketed bids to ad_bids_state Arc<RwLock> - Compute ad_slots_script after response headers; set Cache-Control: private, max-age=0 - Fix Stream arm to thread actual ad_slots_script and ad_bids_state through - Add build_auction_request, build_bid_map, build_bids_script, build_ad_slots_script helpers - Update route_tests.rs to pass empty slots_file to route_request
…m slotRenderEnded
- build_bid_map now returns serde_json::Map with full bid objects (hb_pb,
hb_bidder, hb_adid, nurl, burl) instead of a plain CPM string map
- build_bids_script / build_ad_slots_script now emit full <script> tags
using JSON.parse("…") for safe inline embedding; add html_escape_for_script helper
- build_ad_slots_script uses correct property names (gam_unit_path, div_id,
formats, targeting) matching the client-side TSJS bundle expectations
- Replace map_or(false, …) with is_some_and(…) on lines 546, 549, 567
- Add # Panics doc sections to handle_publisher_request and create_html_processor
…nities.toml at startup
… from slotRenderEnded; slim-Prebid lazy loader
- Enable APS and adserver_mock in auction config; set providers and mediator - Increase auction_timeout_ms from 500ms to 3000ms — 500ms was too tight for HTTPS round-trips to mocktioneer, leaving the mediator zero budget - Fix mediation request: send numeric price instead of opaque encoded_price; mocktioneer requires a decoded price field and does not support encoded_price - Expand creative-opportunities slot page_patterns to include /news/**
Define SlotRenderEndedEvent, SlotRenderEvent, and TestWindow types to eliminate all @typescript-eslint/no-explicit-any violations in gpt/index.ts and gpt/index.test.ts. Extend GptWindow with __tsjs_slim_prebid_url so installSlimPrebidLoader avoids the any cast.
Set gam_network_id to 88059007 (autoblog production network). Update atf_sidebar_ad slot to /88059007/autoblog/news with div_id ad-atf_sidebar-0-_r_2_ (desktop ATF sidebar, 300x250); restrict page_patterns to article paths only (/20**, /news/**) since that div does not exist on the homepage. Add homepage_header_ad slot targeting /88059007/autoblog/homepage with ad-header-0-_R_jpalubtak5lb_ for 970x90/728x90/970x250 leaderboard formats. Reduce auction_timeout_ms from 3000 to 500 to cap TTFB at the spec-recommended ceiling.
The bids script set window.__ts_bids but never invoked the __tsAdInit function, leaving GPT slots undefined and server-side targeting (hb_pb, hb_bidder) never applied. Both the winning-bid path (build_bids_script) and the no-auction fallback (html_processor None branch) now guard-call the function after the assignment.
Adds [slot.providers.pbs.bidders] support so PBS bidder params live in creative-opportunities.toml alongside APS params, without needing PBS stored requests configured server-side. PrebidAuctionProvider now sends imp.ext.prebid.storedrequest.id as a fallback for slots with no inline PBS params, and skips non-PBS provider keys (e.g. "aps") that belong to separate auction providers. PrebidImpExt gains an optional storedrequest field; empty bidder maps are omitted during serialisation. Wires mocktioneer and criteo (placeholder IDs) for both autoblog creative-opportunity slots.
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Summary
Changes
Closes
Closes #677
Test plan
Automated
Manual end-to-end (browser DevTools console)
The steps below build on each other — each step uses data from the previous one so no IDs need to be memorised.
Step 1 — Verify slot config is injected at `` open
Navigate to a news/article URL (a path matching `/20**` or `/news/**`).
Expected: array of slot objects. Each entry has `id`, `gamUnitPath`, `divId`, `formats`, and `targeting`. Note the `divId` value from the matching slot — you will use it in step 3.
What this proves: the edge matched the URL against the slot's page patterns and injected the slot config synchronously in ``, before any JS ran.
Step 2 — Verify server-side auction result is injected before ``
Expected: object keyed by slot ID (same ID as in step 1), containing `hb_bidder` and `hb_pb` from the winning provider. Example: `{ atf_sidebar_ad: { hb_bidder: "aps", hb_pb: "1.50" } }`.
What this proves: the server-side auction (APS + PBS running in parallel) completed, the mediator picked a winner, price was bucketed, and the result was injected into the HTML before the page was sent to the browser. No client-side auction round-trip for these slots.
Step 3 — Verify `__tsAdInit` wired the GPT slot with bid targeting
Using the `divId` observed in step 1:
Expected: one entry with the GAM unit path from step 1 and targeting that includes `hb_pb`, `hb_bidder` (matching step 2), plus any slot-level keys (`pos`, `zone`) and `ts_initial: ["1"]`.
What this proves: `__tsAdInit` ran after `__ts_bids` was set, called `googletag.defineSlot()`, and applied all bid and slot-level targeting. `ts_initial: "1"` confirms it ran from the server-side bid injection path (not a fallback).
Step 4 — Verify slot matching is page-pattern-aware
Navigate to the homepage (`/`). Repeat step 2.
Expected: `window.__ts_bids` contains `homepage_header_ad` (not `atf_sidebar_ad`). Repeat step 3 with the `divId` from `window.__ts_ad_slots` on this page.
What this proves: glob-based page-pattern matching works — each slot only fires on the URLs it is configured for.
Step 5 — Confirm no duplicate injection
View page source (`Cmd+U` / `Ctrl+U`). Search for `__ts_bids`.
Expected: exactly one occurrence of `window.__ts_bids=` in the source, immediately before ``.
What this proves: the `AtomicBool` guard added in this PR prevents double injection on origin pages that contain more than one `` element (common in CMS/template-generated HTML).
Pending (GAM line items required)
Step 6 — In the Elements tab, find the `div` whose `id` matches the `divId` from step 1. When GAM price-priority line items targeting `hb_pb` and `hb_bidder` are configured, this div will contain an `<iframe>` with the winning creative. The pipeline on the Trusted Server side is verified complete by steps 1–5 above; creative delivery requires standard Prebid header-bidding line item setup in GAM (outside this PR's scope).
Checklist