docs: Java restaurant deliveries

.github/workflows/checks.yml

@@ -190,3 +190,8 @@ jobs:
         run: |-
           cd samples/grpc/local-drone-control-java
           mvn compile -nsu -Dakka-projection.version=`cat ~/.version`
+
+      - name: Compile Java Projection gRPC Restaurant Drone Deliveries sample
+        run: |-
+          cd samples/grpc/restaurant-drone-deliveries-service-java
+          mvn compile -nsu -Dakka-projection.version=`cat ~/.version`

samples/grpc/restaurant-drone-deliveries-service-java/LICENSE

@@ -0,0 +1,10 @@
+Akka sample by Lightbend
+
+Licensed under Public Domain (CC0)
+
+To the extent possible under law, the person who associated CC0 with
+this Template has waived all copyright and related or neighboring
+rights to this Template.
+
+You should have received a copy of the CC0 legalcode along with this
+work.  If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.

samples/grpc/restaurant-drone-deliveries-service-java/README.md

@@ -0,0 +1,81 @@
+# Restaurant Drone Deliveries Service
+
+The sample show-cases a service for drones doing restaurant deliveries.
+
+It is intended to be used together with the local-drone-control sample.
+
+* Keeps track of a coarse grained location of each drone to the cloud
+* FIXME Accepts restaurant delivery requests which are then fed to the right local drone control
+
+## Running the sample code
+
+1. Start a local PostgresSQL server on default port 5432. The included `docker-compose.yml` starts everything required for running locally.
+
+ ```shell
+ docker compose up --wait
+
+ # creates the tables needed for Akka Persistence
+ # as well as the offset store table for Akka Projection
+ docker exec -i postgres_db psql -U postgres -t < ddl-scripts/create_tables.sql
+ ```
+
+2. Start a first node:
+
+```shell
+mvn compile exec:exec -DAPP_CONFIG=local1.conf
+```
+
+3. (Optional) Start another node with different ports:
+
+```shell
+mvn compile exec:exec -DAPP_CONFIG=local2.conf
+```
+
+4. (Optional) More can be started:
+
+```shell
+mvn compile exec:exec -DAPP_CONFIG=local3.conf
+```
+
+5. Check for service readiness
+
+ ```shell
+curl http://localhost:9101/ready
+ ```
+
+
+Query a location for drone coordinates
+
+```shell
+grpcurl -d '{"location":"sweden/stockholm/kungsholmen"}' -plaintext localhost:8101 central.drones.DroneOverviewService/GetCoarseDroneLocations
+```
+
+Query the state for a specific drone
+
+```shell
+grpcurl -d '{"drone_id":"drone1"}' -plaintext localhost:8101 central.drones.DroneOverviewService.GetDroneOverview
+```
+
+Set up a restaurant
+
+```shell
+grpcurl -d '{"restaurant_id":"restaurant1","coordinates":{"latitude": 59.330324, "longitude": 18.039568}, "local_control_location_id": "sweden/stockholm/kungsholmen" }' -plaintext localhost:8101 central.deliveries.RestaurantDeliveriesService.SetUpRestaurant
+```
+
+Set up another restaurant, closest to a different local drone control
+
+```shell
+grpcurl -d '{"restaurant_id":"restaurant2","coordinates":{"latitude": 59.342046, "longitude": 18.059095}, "local_control_location_id": "sweden/stockholm/norrmalm" }' -plaintext localhost:8101 central.deliveries.RestaurantDeliveriesService.SetUpRestaurant
+```
+
+Register a delivery for the first restaurant
+
+```shell
+grpcurl -d '{"restaurant_id":"restaurant1","delivery_id": "order1","coordinates":{"latitude": 59.330841, "longitude": 18.038885}}' -plaintext localhost:8101 central.deliveries.RestaurantDeliveriesService.RegisterDelivery
+```
+
+Register a delivery for the second restaurant
+
+```shell
+grpcurl -d '{"restaurant_id":"restaurant2","delivery_id": "order2","coordinates":{"latitude": 59.340128, "longitude": 18.056303}}' -plaintext localhost:8101 central.deliveries.RestaurantDeliveriesService.RegisterDelivery
+```

samples/grpc/restaurant-drone-deliveries-service-java/ddl-scripts/create_tables.sql

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+CREATE TABLE IF NOT EXISTS event_journal(
+  slice INT NOT NULL,
+  entity_type VARCHAR(255) NOT NULL,
+  persistence_id VARCHAR(255) NOT NULL,
+  seq_nr BIGINT NOT NULL,
+  db_timestamp timestamp with time zone NOT NULL,
+
+  event_ser_id INTEGER NOT NULL,
+  event_ser_manifest VARCHAR(255) NOT NULL,
+  event_payload BYTEA NOT NULL,
+
+  deleted BOOLEAN DEFAULT FALSE NOT NULL,
+  writer VARCHAR(255) NOT NULL,
+  adapter_manifest VARCHAR(255),
+  tags TEXT ARRAY,
+
+  meta_ser_id INTEGER,
+  meta_ser_manifest VARCHAR(255),
+  meta_payload BYTEA,
+
+  PRIMARY KEY(persistence_id, seq_nr)
+);
+
+CREATE INDEX IF NOT EXISTS event_journal_slice_idx ON event_journal(slice, entity_type, db_timestamp, seq_nr);
+
+CREATE TABLE IF NOT EXISTS snapshot(
+  slice INT NOT NULL,
+  entity_type VARCHAR(255) NOT NULL,
+  persistence_id VARCHAR(255) NOT NULL,
+  seq_nr BIGINT NOT NULL,
+  write_timestamp BIGINT NOT NULL,
+  ser_id INTEGER NOT NULL,
+  ser_manifest VARCHAR(255) NOT NULL,
+  snapshot BYTEA NOT NULL,
+  meta_ser_id INTEGER,
+  meta_ser_manifest VARCHAR(255),
+  meta_payload BYTEA,
+
+  PRIMARY KEY(persistence_id)
+);
+
+CREATE TABLE IF NOT EXISTS durable_state (
+  slice INT NOT NULL,
+  entity_type VARCHAR(255) NOT NULL,
+  persistence_id VARCHAR(255) NOT NULL,
+  revision BIGINT NOT NULL,
+  db_timestamp timestamp with time zone NOT NULL,
+
+  state_ser_id INTEGER NOT NULL,
+  state_ser_manifest VARCHAR(255),
+  state_payload BYTEA NOT NULL,
+  tags TEXT ARRAY,
+
+  -- additional column
+  location VARCHAR(255),
+
+  PRIMARY KEY(persistence_id, revision)
+);
+
+-- to query drones by location
+CREATE INDEX IF NOT EXISTS durable_state_drone_location_idx ON durable_state(location);
+
+
+-- Timestamp based offsets are stored in this table.
+CREATE TABLE IF NOT EXISTS akka_projection_timestamp_offset_store (
+  projection_name VARCHAR(255) NOT NULL,
+  projection_key VARCHAR(255) NOT NULL,
+  slice INT NOT NULL,
+  persistence_id VARCHAR(255) NOT NULL,
+  seq_nr BIGINT NOT NULL,
+  -- timestamp_offset is the db_timestamp of the original event
+  timestamp_offset timestamp with time zone NOT NULL,
+  -- timestamp_consumed is when the offset was stored
+  -- the consumer lag is timestamp_consumed - timestamp_offset
+  timestamp_consumed timestamp with time zone NOT NULL,
+  PRIMARY KEY(slice, projection_name, timestamp_offset, persistence_id, seq_nr)
+);
+
+CREATE TABLE IF NOT EXISTS akka_projection_management (
+  projection_name VARCHAR(255) NOT NULL,
+  projection_key VARCHAR(255) NOT NULL,
+  paused BOOLEAN NOT NULL,
+  last_updated BIGINT NOT NULL,
+  PRIMARY KEY(projection_name, projection_key)
+);

samples/grpc/restaurant-drone-deliveries-service-java/ddl-scripts/drop_tables.sql

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+DROP TABLE event_journal;
+DROP TABLE snapshot;
+DROP TABLE durable_state;
+DROP TABLE akka_projection_timestamp_offset_store;
+DROP TABLE akka_projection_management;

samples/grpc/restaurant-drone-deliveries-service-java/docker-compose.yml

@@ -0,0 +1,16 @@
+version: '2.2'
+services:
+  postgres-db:
+    image: postgres:latest
+    container_name: postgres_db
+    ports:
+      - 5432:5432
+    environment:
+      POSTGRES_USER: postgres
+      POSTGRES_PASSWORD: postgres
+    healthcheck:
+      test: ['CMD', 'pg_isready', "-q", "-d", "postgres", "-U", "postgres"]
+      interval: 5s
+      retries: 5
+      start_period: 5s
+      timeout: 5s