Use $BASE_URL variable in docs/api.md curl examples

Co-Authored-By: Claude <noreply@anthropic.com>

README.md

@@ -59,7 +59,8 @@ kubectl get px -w
 # proxy-kubernetes-sample   Managed   kubernetes   Ready   10.244.x.x   True
 ```
 
-Once it's `Ready`, port-forward the discovery API and use it:
+Once it's `Ready`, port-forward the discovery API and use it (full
+reference with schemas and error codes: [docs/api.md](docs/api.md)):
 
 ```sh
 kubectl -n egress-proxies-operator-system port-forward \

docs/api.md

@@ -0,0 +1,323 @@
+# Discovery API reference
+
+The operator serves an HTTP API (the *discovery API*) that crawler clients
+use to find and lease egress proxies: list healthy proxies filtered by
+attributes, acquire a TTL-based lease on one, release it early, and report
+how a target site treated the proxy. It is implemented in
+[`internal/discovery`](../internal/discovery/) with lease state in
+[`internal/lease`](../internal/lease/); the only Kubernetes interaction is
+reading `Proxy` resources from the manager's cache.
+
+## Base URL
+
+The API listens on `:8090` (`--discovery-addr`) inside the manager pod and
+is exposed by a Service
+([config/default/discovery_service.yaml](../config/default/discovery_service.yaml)).
+
+In-cluster:
+
+```text
+http://egress-proxies-operator-controller-manager-discovery-service.egress-proxies-operator-system.svc.cluster.local:8090
+```
+
+From a workstation, port-forward:
+
+```sh
+kubectl -n egress-proxies-operator-system port-forward \
+  svc/egress-proxies-operator-controller-manager-discovery-service 8090:8090 &
+```
+
+Set `BASE_URL` to wherever you reach the API; all examples below use it:
+
+```sh
+export BASE_URL=localhost:8090   # via the port-forward above
+# or, from inside the cluster:
+# export BASE_URL=http://egress-proxies-operator-controller-manager-discovery-service.egress-proxies-operator-system.svc.cluster.local:8090
+```
+
+## Authentication
+
+A single static bearer token, read from the `DISCOVERY_TOKEN` environment
+variable at startup. The shipped Deployment populates it from the
+`discovery-token` Secret (key `token`), which is **optional** — if the
+Secret is absent or the token is empty, the API serves **unauthenticated**
+(the manager logs a loud warning at startup). Create the Secret:
+
+```sh
+kubectl -n egress-proxies-operator-system create secret generic discovery-token \
+  --from-literal=token="$(openssl rand -hex 24)"
+```
+
+Send the token on every request:
+
+```sh
+export TOKEN=<the token>
+curl -s -H "Authorization: Bearer $TOKEN" "$BASE_URL/v1/proxies" | jq
+```
+
+A missing or wrong token gets `401 {"error":"unauthorized",...}`.
+`GET /healthz` is always exempt.
+
+The curl examples below omit the `-H "Authorization: Bearer $TOKEN"` flag
+for brevity — add it to every call when auth is enabled.
+
+## Conventions
+
+- Requests and responses are JSON. Errors share one envelope:
+
+  ```json
+  {"error": "<machine_code>", "message": "<human-readable text>"}
+  ```
+
+- Request bodies are capped at **64 KiB** (larger bodies fail the JSON
+  decode with `400 invalid_body`).
+- Proxies with a deletion timestamp (being finalized) are excluded from
+  every response and never offered for lease.
+
+## Configuration
+
+| Setting | Default | Meaning |
+|---|---|---|
+| `--discovery-addr` | `:8090` | Listen address of the API |
+| `--max-lease-ttl` | `1h` | Maximum `ttlSeconds` a client may request |
+| `--lease-cooldown` | `15m` | Cooldown window applied on `rate_limited`/`banned` reports |
+| `DISCOVERY_TOKEN` (env) | empty | Bearer token; empty disables auth |
+
+The shipped Deployment passes none of these flags, so the defaults apply.
+
+## Endpoints
+
+### `GET /healthz`
+
+Liveness check. Unauthenticated, always `200` with body `ok`.
+
+```sh
+curl -s "$BASE_URL/healthz"
+```
+
+### `GET /v1/proxies` — list proxies
+
+Query parameters (all optional):
+
+| Parameter | Values | Effect |
+|---|---|---|
+| `healthy` | `true` \| `false` | Keep only proxies whose `Healthy` condition matches. Any other value → `400 invalid_query`. |
+| `attr.<key>` | any string | Exact match on `spec.attributes[<key>]`. Repeatable; **all** given pairs must match. |
+
+List everything:
+
+```sh
+curl -s "$BASE_URL/v1/proxies" | jq
+```
+
+List healthy proxies in a given geo:
+
+```sh
+curl -s "$BASE_URL/v1/proxies?healthy=true&attr.geo=eu" | jq
+```
+
+Response — `200`, proxies sorted by `id`, an empty match is `200` with
+`"count": 0` (never `404`):
+
+```json
+{
+  "proxies": [
+    {
+      "id": "default/proxy-kubernetes-sample",
+      "ip": "10.244.1.7",
+      "port": 3128,
+      "attributes": {"geo": "local"},
+      "phase": "Ready",
+      "healthy": true,
+      "latencyMillis": 42,
+      "activeLeases": 1,
+      "maxLeases": 5
+    }
+  ],
+  "count": 1
+}
+```
+
+Proxy object fields (the same shape appears inside lease responses):
+
+| Field | Meaning |
+|---|---|
+| `id` | `namespace/name` of the `Proxy` resource; used as the stable key everywhere |
+| `ip` | Effective host — `spec.endpoint.host` for `External` proxies, `status.ip` for `Managed` (empty until the backing VM/pod is up) |
+| `port` | Effective port (default `3128`) |
+| `attributes` | `spec.attributes` — free-form selection labels (`geo`, `asn`, `purpose`, …); omitted when empty |
+| `phase` | `Pending` \| `Provisioning` \| `Ready` \| `Unhealthy` \| `Deleting` \| `Failed` |
+| `healthy` | `true` iff the `Healthy` condition is `True` (the through-the-proxy health probe passes) |
+| `latencyMillis` | Latency of the last status-affecting health probe |
+| `activeLeases` | Currently active leases on this proxy |
+| `maxLeases` | Lease capacity (default `5`; an explicit `0` means unleasable) |
+
+### `POST /v1/leases` — acquire a lease
+
+Picks a healthy proxy with free capacity matching the selector and grants
+an exclusive-slot, TTL-based lease on it.
+
+Request body (every field optional; `{}` is valid):
+
+```json
+{
+  "selector": {"geo": "eu"},
+  "ttlSeconds": 300,
+  "target": "example.com"
+}
+```
+
+| Field | Default | Meaning |
+|---|---|---|
+| `selector` | none | Attribute equality filter, same semantics as `attr.<key>` above |
+| `ttlSeconds` | `300` (5 min) | Lease lifetime; must be ≤ `--max-lease-ttl` (default 1 h), else `400 invalid_ttl` |
+| `target` | none | The site you intend to crawl; enables per-target cooldowns (see below) |
+
+```sh
+curl -s -XPOST "$BASE_URL/v1/leases" \
+  -d '{"selector":{"geo":"eu"},"ttlSeconds":300,"target":"example.com"}' | jq
+```
+
+Success — `201`:
+
+```json
+{
+  "leaseID": "P3X6HHQTPCM5UTGVGE3B5UPS3A",
+  "proxy": {
+    "id": "default/proxy-eu-1",
+    "ip": "34.88.10.20",
+    "port": 3128,
+    "attributes": {"geo": "eu"},
+    "phase": "Ready",
+    "healthy": true,
+    "latencyMillis": 42,
+    "activeLeases": 1,
+    "maxLeases": 5
+  },
+  "expiresAt": "2026-08-11T22:05:00Z",
+  "ttlSeconds": 300
+}
+```
+
+Use `proxy.ip` and `proxy.port` as an HTTP proxy for the lease's lifetime:
+
+```sh
+curl -x http://34.88.10.20:3128 https://example.com
+```
+
+No match — `409` with diagnostic counts explaining why nothing qualified:
+
+```json
+{
+  "error": "no_match",
+  "message": "no healthy proxy with free capacity matched the selector",
+  "considered": 3,
+  "atCapacity": 1,
+  "inCooldown": 1,
+  "unhealthy": 1
+}
+```
+
+| Count | Meaning |
+|---|---|
+| `considered` | Proxies that matched the selector (before health/capacity checks) |
+| `atCapacity` | Skipped because `activeLeases >= maxLeases` |
+| `inCooldown` | Skipped because of an active cooldown for this target (or a global one) |
+| `unhealthy` | Skipped because the `Healthy` condition is not `True` |
+
+Leases expire on their own — releasing is only needed to free the slot
+early. There is no renew/extend endpoint; acquire a new lease instead.
+
+### `DELETE /v1/leases/{id}` — release early
+
+Frees the lease's capacity slot immediately. Idempotent: always `204`,
+including for unknown or already-expired lease IDs.
+
+```sh
+curl -si -XDELETE "$BASE_URL/v1/leases/P3X6HHQTPCM5UTGVGE3B5UPS3A"
+```
+
+### `POST /v1/leases/{id}/report` — report an outcome
+
+Tell the operator how the target site treated the proxy. This is the
+feedback signal that drives cooldowns.
+
+Request body:
+
+```json
+{"result": "rate_limited", "target": "example.com"}
+```
+
+| Field | Values | Meaning |
+|---|---|---|
+| `result` | `ok` \| `rate_limited` \| `banned` | Anything else → `400 invalid_result` |
+| `target` | optional | Which site produced the result; falls back to the lease's `target`, then to global |
+
+```sh
+curl -si -XPOST "$BASE_URL/v1/leases/P3X6HHQTPCM5UTGVGE3B5UPS3A/report" \
+  -d '{"result":"rate_limited","target":"example.com"}'
+```
+
+Responses: `204` on success, `404 unknown_lease` if the lease ID was never
+issued or has aged out.
+
+Semantics:
+
+- `ok` is a pure acknowledgement — nothing is recorded.
+- `rate_limited` and `banned` currently behave **identically**: both put
+  the proxy in one cooldown window (default 15 min, `--lease-cooldown`)
+  for the resolved target.
+- An expired lease remains reportable for one cooldown window past its
+  TTL, so a late "we got rate-limited" still lands.
+
+## Proxy selection and cooldowns
+
+How `POST /v1/leases` picks among eligible proxies (healthy, matching the
+selector, not being deleted, not at capacity, not in cooldown), in order:
+
+1. fewest `activeLeases` (least-loaded),
+2. lowest `latencyMillis`,
+3. lexicographic `id` (deterministic tie-break).
+
+Cooldowns are keyed by **(proxy, target)**:
+
+- A report **with a target** blocks that proxy only for lease requests
+  naming the **same target**. Other targets — and requests with no
+  target — still get the proxy.
+- A report **without a target**, on a lease that also had no target,
+  creates a **global** cooldown: the proxy is blocked for *all* lease
+  requests until the window passes. Always pass `target` on leases and
+  reports unless you really mean "this proxy is bad for everyone".
+
+## End-to-end example
+
+```sh
+# 1. Acquire a lease for crawling example.com through an EU proxy
+LEASE=$(curl -s -XPOST "$BASE_URL/v1/leases" \
+  -H "Authorization: Bearer $TOKEN" \
+  -d '{"selector":{"geo":"eu"},"ttlSeconds":600,"target":"example.com"}')
+LEASE_ID=$(echo "$LEASE" | jq -r .leaseID)
+PROXY=$(echo "$LEASE" | jq -r '"\(.proxy.ip):\(.proxy.port)"')
+
+# 2. Crawl through the leased proxy
+curl -x "http://$PROXY" https://example.com/some/page
+
+# 3. Got a 429? Report it — example.com-bound leases will avoid this
+#    proxy for the next 15 minutes
+curl -s -XPOST "$BASE_URL/v1/leases/$LEASE_ID/report" \
+  -H "Authorization: Bearer $TOKEN" \
+  -d '{"result":"rate_limited","target":"example.com"}'
+
+# 4. Done early? Release the slot (otherwise the TTL frees it)
+curl -s -XDELETE "$BASE_URL/v1/leases/$LEASE_ID" \
+  -H "Authorization: Bearer $TOKEN"
+```
+
+## Caveats
+
+- **Lease and cooldown state is in-memory and per-process.** An operator
+  restart drops all active leases and cooldowns. Clients must tolerate a
+  granted lease disappearing (a subsequent report returns `404`).
+- **Run a single replica.** The API is served by every manager replica but
+  is not leader-elected, and lease state is not shared between replicas;
+  the shipped Deployment pins `replicas: 1`.

docs/architecture.md

@@ -213,6 +213,8 @@ Kubernetes interaction is reading Proxies from the manager's cache. The
 server is a non-leader-elected Runnable (all replicas would serve, but the
 deployment ships `replicas: 1` because lease state is per-process — an
 operator restart drops all leases and cooldowns, a documented caveat).
+Client-facing reference with request/response schemas and curl examples:
+[api.md](api.md).
 
 ```text
 crawler client

docs/plans-executions/2026-08-11-2152-discovery-api-docs.md

@@ -0,0 +1,38 @@
+# Execution: Discovery API documentation
+
+Plan: [2026-08-11-2152-discovery-api-docs.md](../plans/2026-08-11-2152-discovery-api-docs.md)
+
+- [x] Step 1 — Write `docs/api.md` full API reference
+- [x] Step 2 — Add pointers in README and architecture.md
+
+## Step 1 — docs/api.md
+
+Wrote the full reference: base URL (in-cluster FQDN + port-forward), bearer
+auth, error envelope, configuration table, all five routes with schemas,
+status codes and curl examples, the selection/cooldown semantics section,
+an end-to-end curl walkthrough, and the in-memory/single-replica caveats.
+All facts were taken from the code, not from memory of prior docs.
+
+Worth noting: the doc explicitly calls out two things no earlier doc
+stated for clients — that a report **without** a target on a targetless
+lease creates a *global* cooldown (blocking the proxy for everyone), and
+that `rate_limited` and `banned` currently behave identically. Both came
+straight from `internal/lease/store.go` and are easy to trip over.
+
+## Step 2 — Pointers + verification
+
+Added one-line links to the new doc in README's quickstart (above the curl
+block) and in `docs/architecture.md` §7. Verified the documented behavior
+against the tree rather than trusting the write-up:
+
+```sh
+go build ./... && go test -short ./internal/discovery/ ./internal/lease/
+```
+
+Both pass; a grep of `server_test.go` confirmed every documented status
+code and error code (`invalid_ttl`, `invalid_query`, `invalid_result`,
+`no_match`, `unknown_lease`, 201/204/401/404/409) is asserted by tests.
+
+Worth noting: CHANGELOG entry deliberately deferred until the user
+confirms the docs read well, per the CHANGELOG convention's
+"once the user confirms it works" clause.

docs/plans/2026-08-11-2152-discovery-api-docs.md

@@ -0,0 +1,58 @@
+# Plan: Discovery API documentation (docs/api.md)
+**Created:** 2026-08-11 21:52
+
+
+## Context
+
+The operator serves an HTTP discovery/lease API on `:8090` ([internal/discovery/](internal/discovery/)) that crawler clients use to list proxies, acquire TTL leases, release them, and report rate-limiting. There is no dedicated API reference today: README has four quickstart curls (no auth header, no schemas), and `docs/architecture.md` §7 has an ASCII route map. The user wants full documentation with curl examples for every feature.
+
+**Decisions made with user:** doc lives in a new `docs/api.md`; commit straight to `main` (no MR).
+
+## Deliverable
+
+### 1. New file `docs/api.md` — full API reference
+
+Content (all facts verified against code during planning):
+
+- **Overview & base URL** — what the API is; in-cluster FQDN `http://egress-proxies-operator-controller-manager-discovery-service.egress-proxies-operator-system.svc.cluster.local:8090` (Service: `config/default/discovery_service.yaml`); local access via `kubectl port-forward svc/egress-proxies-operator-controller-manager-discovery-service 8090:8090`.
+- **Authentication** — static bearer token from `DISCOVERY_TOKEN` env var (populated from the optional `discovery-token` Secret, key `token`; `config/manager/manager.yaml`). Empty token ⇒ auth disabled with startup warning. Curl: `-H "Authorization: Bearer $TOKEN"` on every example. `/healthz` always exempt.
+- **Conventions** — JSON everywhere; error envelope `{"error":"<code>","message":"<text>"}`; request bodies capped at 64 KiB; proxies with a deletion timestamp are excluded from all responses.
+- **Configuration table** — `--discovery-addr` (default `:8090`), `--max-lease-ttl` (default 1h), `--lease-cooldown` (default 15m), `DISCOVERY_TOKEN`. Note the shipped Deployment passes none of these flags, so defaults apply.
+- **Endpoints**, each with request/response schema, status codes, and a copy-pasteable curl example:
+  - `GET /healthz` — liveness, unauthenticated.
+  - `GET /v1/proxies` — filters `healthy=true|false` (else 400 `invalid_query`) and repeatable `attr.<key>=<value>` (verbatim equality on `spec.attributes`, all pairs must match). Response `{"proxies":[proxyView...],"count":N}` sorted by id. Full `proxyView` field table: `id` (ns/name), `ip`, `port`, `attributes`, `phase` (Pending/Provisioning/Ready/Unhealthy/Deleting/Failed), `healthy` (condition `Healthy` == True), `latencyMillis`, `activeLeases`, `maxLeases` (default 5; explicit 0 = unleasable).
+  - `POST /v1/leases` — body `{selector, ttlSeconds, target}` all optional; TTL defaults 5m, capped at max-lease-ttl (else 400 `invalid_ttl`). 201 `{leaseID, proxy, expiresAt, ttlSeconds}`; 409 `no_match` with `considered/atCapacity/inCooldown/unhealthy` counts (documented meanings).
+  - `DELETE /v1/leases/{id}` — early release; always 204, idempotent.
+  - `POST /v1/leases/{id}/report` — body `{result: ok|rate_limited|banned, target}`; 204, 404 `unknown_lease`, 400 `invalid_result`. `ok` is a pure ack; `rate_limited` and `banned` behave identically today (both start one cooldown window).
+- **Selection & cooldown semantics** (short section — this is the non-obvious part clients need):
+  - Selection order: fewest active leases → lowest latency → lexicographic id; deterministic; only healthy, non-deleting proxies with free capacity are candidates.
+  - Cooldown: 15m default (`--lease-cooldown`), keyed `{proxy, target}`. Report with a target blocks only leases requesting that target; report without a target (and lease without one) creates a **global** cooldown blocking all acquisitions of that proxy — call this footgun out explicitly.
+  - Expired leases stay reportable for one cooldown window past TTL.
+- **End-to-end workflow example** — numbered curl walkthrough: acquire → use `proxy.ip:port` as HTTP proxy (`curl -x`) → report `rate_limited` on 429 → release. Using a `jq`-extracted `leaseID`.
+- **Caveats** — lease/cooldown state is in-memory and per-process: single replica only, operator restart drops all leases and cooldowns.
+
+### 2. Pointers to the new doc (small edits)
+
+- `README.md`: one-line link near the quickstart curl section ("full reference: docs/api.md").
+- `docs/architecture.md` §7: one-line link to `docs/api.md` as the detailed reference.
+
+### 3. Housekeeping per CLAUDE.md
+
+- First action post-approval: copy this plan to `docs/plans/<timestamp>-discovery-api-docs.md` (timestamp from `date "+%Y-%m-%d-%H%M"`), commit it alone.
+- Then write the docs, commit to `main` with `Co-Authored-By: Claude <noreply@anthropic.com>` trailer, push.
+- Append execution summary + status checklist to `docs/plans-executions/<same-timestamp>-discovery-api-docs.md` in the docs commit.
+- Add `CHANGELOG.md` entry (timestamp via `date "+%Y-%m-%d %H:%M %Z"`) once the user confirms.
+
+## Key source files (facts source of truth)
+
+- [internal/discovery/handlers.go](internal/discovery/handlers.go), [internal/discovery/server.go](internal/discovery/server.go) — routes, schemas, status codes, auth, limits.
+- [internal/lease/store.go](internal/lease/store.go) — selection order, cooldown/retention, stats.
+- [api/v1alpha1/proxy_types.go](api/v1alpha1/proxy_types.go), [api/v1alpha1/helpers.go](api/v1alpha1/helpers.go) — defaults (port 3128, maxLeases 5), phases, conditions.
+- [cmd/main.go](cmd/main.go) — flags/env defaults.
+- [config/default/discovery_service.yaml](config/default/discovery_service.yaml), [config/manager/manager.yaml](config/manager/manager.yaml) — service DNS, token secret.
+
+## Verification
+
+- Cross-check every documented status code / field name against `internal/discovery/server_test.go` expectations.
+- Sanity-run `go build ./... && go test -short ./internal/discovery/ ./internal/lease/` (no code changes expected — confirms docs match current behavior, not a stale tree).
+- Optionally lint the curl JSON bodies by piping each through `jq .` locally.