upgrade deps

README.md

@@ -76,6 +76,101 @@ go build .
 go test ./...
 ```
 
+## HTTP API Quick Start (curl Examples)
+
+Assuming the service is reachable at http://localhost:8080 and the cart API is mounted at /cart.
+Most endpoints use an HTTP cookie named `cartid` to track the cart. The first request will set it.
+
+### 1. Get (or create) a cart
+```bash
+curl -i http://localhost:8080/cart/
+```
+Response sets a `cartid` cookie and returns the current (possibly empty) cart JSON.
+
+### 2. Add an item by SKU (implicit quantity = 1)
+```bash
+curl -i --cookie-jar cookies.txt http://localhost:8080/cart/add/TEST-SKU-123
+```
+Stores cookie in `cookies.txt` for subsequent calls.
+
+### 3. Add an item with explicit payload (country, quantity)
+```bash
+curl -i --cookie cookies.txt \
+  -H "Content-Type: application/json" \
+  -d '{"sku":"TEST-SKU-456","quantity":2,"country":"se"}' \
+  http://localhost:8080/cart/
+```
+
+### 4. Change quantity of an existing line
+(First list the cart to find `id` of the line; here we use id=1 as an example)
+```bash
+curl -i --cookie cookies.txt \
+  -X PUT -H "Content-Type: application/json" \
+  -d '{"id":1,"quantity":3}' \
+  http://localhost:8080/cart/
+```
+
+### 5. Remove an item
+```bash
+curl -i --cookie cookies.txt -X DELETE http://localhost:8080/cart/1
+```
+
+### 6. Set entire cart contents (overwrites items)
+```bash
+curl -i --cookie cookies.txt \
+  -X POST -H "Content-Type: application/json" \
+  -d '{"items":[{"sku":"TEST-SKU-AAA","quantity":1,"country":"se"},{"sku":"TEST-SKU-BBB","quantity":2,"country":"se"}]}' \
+  http://localhost:8080/cart/set
+```
+
+### 7. Add a delivery (provider + optional items)
+If `items` is empty or omitted, all items without a delivery get this one.
+```bash
+curl -i --cookie cookies.txt \
+  -X POST -H "Content-Type: application/json" \
+  -d '{"provider":"standard","items":[1,2]}' \
+  http://localhost:8080/cart/delivery
+```
+
+### 8. Remove a delivery by deliveryId
+```bash
+curl -i --cookie cookies.txt -X DELETE http://localhost:8080/cart/delivery/1
+```
+
+### 9. Set a pickup point for a delivery
+```bash
+curl -i --cookie cookies.txt \
+  -X PUT -H "Content-Type: application/json" \
+  -d '{"id":"PUP123","name":"Locker 5","address":"Main St 1","city":"Stockholm","zip":"11122","country":"SE"}' \
+  http://localhost:8080/cart/delivery/1/pickupPoint
+```
+
+### 10. Checkout (returns HTML snippet from Klarna)
+```bash
+curl -i --cookie cookies.txt http://localhost:8080/cart/checkout
+```
+
+### 11. Using a known cart id directly (bypassing cookie)
+If you already have a cart id (e.g. 1720000000000000):
+```bash
+CART_ID=1720000000000000
+curl -i http://localhost:8080/cart/byid/$CART_ID
+curl -i -X POST -H "Content-Type: application/json" \
+  -d '{"sku":"TEST-SKU-XYZ","quantity":1,"country":"se"}' \
+  http://localhost:8080/cart/byid/$CART_ID
+```
+
+### 12. Clear cart cookie (forces a new cart on next request)
+```bash
+curl -i --cookie cookies.txt -X DELETE http://localhost:8080/cart/
+```
+
+Tip: Use `--cookie-jar` and `--cookie` to persist the session across multiple commands:
+```bash
+curl --cookie-jar cookies.txt http://localhost:8080/cart/
+curl --cookie cookies.txt http://localhost:8080/cart/add/TEST-SKU-123
+```
+
 ## Important Notes
 
 - Always regenerate protobuf Go code after modifying any `.proto` files (messages/cart_actor/control_plane)