.sqlx/query-2877f56715e3768acad466dc46be88525fba13a20c0587239e833616ff4b7887.json

@@ -0,0 +1,22 @@
+{
+  "db_name": "PostgreSQL",
+  "query": "SELECT EXISTS (\n                SELECT 1\n                    FROM cqrs_inventory_store_query\n                WHERE\n                    store_id = $1\n            );",
+  "describe": {
+    "columns": [
+      {
+        "ordinal": 0,
+        "name": "exists",
+        "type_info": "Bool"
+      }
+    ],
+    "parameters": {
+      "Left": [
+        "Uuid"
+      ]
+    },
+    "nullable": [
+      null
+    ]
+  },
+  "hash": "2877f56715e3768acad466dc46be88525fba13a20c0587239e833616ff4b7887"
+}

.sqlx/query-4d7b12d7ff5e008054bab7aa61d6ba1f559293608196e540788947789cad244c.json

@@ -0,0 +1,40 @@
+{
+  "db_name": "PostgreSQL",
+  "query": "SELECT \n                name, address, store_id, owner\n             FROM\n                cqrs_inventory_store_query\n            WHERE\n                view_id = $1;",
+  "describe": {
+    "columns": [
+      {
+        "ordinal": 0,
+        "name": "name",
+        "type_info": "Text"
+      },
+      {
+        "ordinal": 1,
+        "name": "address",
+        "type_info": "Text"
+      },
+      {
+        "ordinal": 2,
+        "name": "store_id",
+        "type_info": "Uuid"
+      },
+      {
+        "ordinal": 3,
+        "name": "owner",
+        "type_info": "Text"
+      }
+    ],
+    "parameters": {
+      "Left": [
+        "Text"
+      ]
+    },
+    "nullable": [
+      false,
+      true,
+      false,
+      false
+    ]
+  },
+  "hash": "4d7b12d7ff5e008054bab7aa61d6ba1f559293608196e540788947789cad244c"
+}

.sqlx/query-bb92f2d0c882653e92f2837353c1def62da1715c65214a4d404a5ce551c501bd.json

@@ -0,0 +1,19 @@
+{
+  "db_name": "PostgreSQL",
+  "query": "UPDATE\n                        cqrs_inventory_store_query\n                    SET\n                        view_id = $1,\n                        version = $2,\n                        name = $3,\n                        address = $4,\n                        store_id = $5,\n                        owner = $6;",
+  "describe": {
+    "columns": [],
+    "parameters": {
+      "Left": [
+        "Text",
+        "Int8",
+        "Text",
+        "Text",
+        "Uuid",
+        "Text"
+      ]
+    },
+    "nullable": []
+  },
+  "hash": "bb92f2d0c882653e92f2837353c1def62da1715c65214a4d404a5ce551c501bd"
+}

.sqlx/query-c6e90aa1e4fc851ac37318ada15859bc6e2fb1a75da0ed248debf126ba39c1d1.json

@@ -0,0 +1,28 @@
+{
+  "db_name": "PostgreSQL",
+  "query": "SELECT \n                view_id, version\n             FROM\n                cqrs_inventory_store_query\n            WHERE\n                view_id = $1;",
+  "describe": {
+    "columns": [
+      {
+        "ordinal": 0,
+        "name": "view_id",
+        "type_info": "Text"
+      },
+      {
+        "ordinal": 1,
+        "name": "version",
+        "type_info": "Int8"
+      }
+    ],
+    "parameters": {
+      "Left": [
+        "Text"
+      ]
+    },
+    "nullable": [
+      false,
+      false
+    ]
+  },
+  "hash": "c6e90aa1e4fc851ac37318ada15859bc6e2fb1a75da0ed248debf126ba39c1d1"
+}

.sqlx/query-eb97288edbbbe8c5f30454040584a3e182ba5f4a303c142668956be3846c6d18.json

@@ -0,0 +1,19 @@
+{
+  "db_name": "PostgreSQL",
+  "query": "INSERT INTO cqrs_inventory_store_query (\n                        view_id, version, name, address, store_id, owner\n                    ) VALUES (\n                        $1, $2, $3, $4, $5, $6\n                    );",
+  "describe": {
+    "columns": [],
+    "parameters": {
+      "Left": [
+        "Text",
+        "Int8",
+        "Text",
+        "Text",
+        "Uuid",
+        "Text"
+      ]
+    },
+    "nullable": []
+  },
+  "hash": "eb97288edbbbe8c5f30454040584a3e182ba5f4a303c142668956be3846c6d18"
+}

Cargo.lock

@@ -3228,6 +3228,7 @@ dependencies = [
  "tokio-stream",
  "tracing",
  "url",
+ "uuid",
  "webpki-roots 0.25.4",
 ]
 
@@ -3310,6 +3311,7 @@ dependencies = [
  "thiserror",
  "time",
  "tracing",
+ "uuid",
  "whoami",
 ]
 
@@ -3349,6 +3351,7 @@ dependencies = [
  "thiserror",
  "time",
  "tracing",
+ "uuid",
  "whoami",
 ]
 
@@ -3374,6 +3377,7 @@ dependencies = [
  "tracing",
  "url",
  "urlencoding",
+ "uuid",
 ]
 
 [[package]]
@@ -3952,11 +3956,12 @@ checksum = "09cc8ee72d2a9becf2f2febe0205bbed8fc6615b7cb429ad062dc7b7ddd036a9"
 
 [[package]]
 name = "uuid"
-version = "1.8.0"
+version = "1.10.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a183cf7feeba97b4dd1c0d46788634f6221d87fa961b305bed08c851829efcc0"
+checksum = "81dfa00651efa65069b0b6b651f4aaa31ba9e3c3ce0137aaad053604ee7e0314"
 dependencies = [
  "getrandom",
+ "serde",
 ]
 
 [[package]]
@@ -4062,6 +4067,7 @@ dependencies = [
  "tracing",
  "tracing-actix-web",
  "url",
+ "uuid",
  "validator 0.18.1",
 ]
 

Cargo.toml

@@ -28,12 +28,13 @@ rand = "0.8.5"
 rust-embed = { version = "8.4.0", features = ["include-exclude"] }
 serde = { version = "1.0.201", features = ["derive"] }
 serde_json = "1.0.117"
-sqlx = { version = "0.7.4", features = ["runtime-tokio-rustls", "postgres", "time"] }
+sqlx = { version = "0.7.4", features = ["runtime-tokio-rustls", "postgres", "time", "uuid"] }
 tera = "1.19.1"
 time = { version = "0.3.36", features = ["serde"] }
 tracing = { version = "0.1.40", features = ["log"] }
 tracing-actix-web = "0.7.10"
 url = { version = "2.5.0", features = ["serde"] }
+uuid = { version = "1.10.0", features = ["v4", "serde"] }
 validator = { version = "0.18.1", features = ["derive"] }
 
 [dev-dependencies]

migrations/20240713080804_cqrs_inventory_store_query.sql

@@ -0,0 +1,32 @@
+--- SPDX-FileCopyrightText: 2024 Aravinth Manivannan <realaravinth@batsense.net>
+--
+-- SPDX-License-Identifier: AGPL-3.0-or-later
+
+CREATE TABLE IF NOT EXISTS categoty_events
+(
+    aggregate_type text                         NOT NULL,
+    aggregate_id   text                         NOT NULL,
+    sequence       bigint CHECK (sequence >= 0) NOT NULL,
+    event_type     text                         NOT NULL,
+    event_version  text                         NOT NULL,
+    payload        json                         NOT NULL,
+    metadata       json                         NOT NULL,
+    timestamp      timestamp with time zone DEFAULT (CURRENT_TIMESTAMP),
+    PRIMARY KEY (aggregate_type, aggregate_id, sequence)
+);
+
+CREATE TABLE IF NOT EXISTS cqrs_inventory_store_query
+(
+    view_id text                        NOT NULL,
+    version           bigint CHECK (version >= 0) NOT NULL,
+
+	name TEXT NOT NULL,
+	address TEXT,
+	owner TEXT NOT NULL,
+	store_id UUID NOT NULL UNIQUE,
+	deleted BOOLEAN NOT NULL DEFAULT FALSE,
+
+    PRIMARY KEY (view_id)
+);
+
+CREATE UNIQUE INDEX IF NOT EXISTS store_store_id_index ON cqrs_inventory_store_query (store_id);

src/inventory/adapters/output/db/mod.rs

@@ -0,0 +1 @@
+pub mod postgres;

src/inventory/adapters/output/db/postgres/errors.rs

@@ -0,0 +1,79 @@
+// SPDX-FileCopyrightText: 2024 Aravinth Manivannan <realaravinth@batsense.net>
+//
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+use std::borrow::Cow;
+
+use cqrs_es::persist::PersistenceError;
+use sqlx::Error as SqlxError;
+
+use crate::inventory::application::port::output::db::errors::InventoryDBError;
+
+impl From<SqlxError> for InventoryDBError {
+    fn from(e: SqlxError) -> Self {
+        log::error!("[postgres] err: {}", e);
+        if let SqlxError::Database(err) = e {
+            if err.code() == Some(Cow::from("23505")) {
+                let msg = err.message();
+                if msg.contains("cqrs_inventory_store_query_store_id_key") {
+                    return Self::DuplicateStoreID;
+                } else {
+                    println!("{msg}");
+                }
+            }
+        }
+        Self::InternalError
+    }
+}
+
+/// map custom row not found error to DB error
+pub fn map_row_not_found_err(e: SqlxError, row_not_found: InventoryDBError) -> InventoryDBError {
+    if let SqlxError::RowNotFound = e {
+        row_not_found
+    } else {
+        e.into()
+    }
+}
+
+#[derive(Debug)]
+pub enum PostgresAggregateError {
+    OptimisticLock,
+    ConnectionError(Box<dyn std::error::Error + Send + Sync + 'static>),
+    DeserializationError(Box<dyn std::error::Error + Send + Sync + 'static>),
+    UnknownError(Box<dyn std::error::Error + Send + Sync + 'static>),
+}
+
+impl From<SqlxError> for PostgresAggregateError {
+    fn from(err: SqlxError) -> Self {
+        // TODO: improve error handling
+        match &err {
+            SqlxError::Database(database_error) => {
+                if let Some(code) = database_error.code() {
+                    if code.as_ref() == "23505" {
+                        return PostgresAggregateError::OptimisticLock;
+                    }
+                }
+                PostgresAggregateError::UnknownError(Box::new(err))
+            }
+            SqlxError::Io(_) | SqlxError::Tls(_) => {
+                PostgresAggregateError::ConnectionError(Box::new(err))
+            }
+            _ => PostgresAggregateError::UnknownError(Box::new(err)),
+        }
+    }
+}
+
+impl From<PostgresAggregateError> for PersistenceError {
+    fn from(err: PostgresAggregateError) -> Self {
+        match err {
+            PostgresAggregateError::OptimisticLock => PersistenceError::OptimisticLockError,
+            PostgresAggregateError::ConnectionError(error) => {
+                PersistenceError::ConnectionError(error)
+            }
+            PostgresAggregateError::DeserializationError(error) => {
+                PersistenceError::UnknownError(error)
+            }
+            PostgresAggregateError::UnknownError(error) => PersistenceError::UnknownError(error),
+        }
+    }
+}

src/inventory/adapters/output/db/postgres/mod.rs

@@ -0,0 +1,27 @@
+// SPDX-FileCopyrightText: 2024 Aravinth Manivannan <realaravinth@batsense.net>
+//
+// SPDX-License-Identifier: AGPL-3.0-or-later
+use std::sync::Arc;
+
+use sqlx::postgres::PgPool;
+
+use crate::db::{migrate::RunMigrations, sqlx_postgres::Postgres};
+
+mod errors;
+mod store_id_exists;
+mod store_view;
+
+#[derive(Clone)]
+pub struct InventoryDBPostgresAdapter {
+    pool: PgPool,
+}
+
+impl InventoryDBPostgresAdapter {
+    pub fn new(pool: PgPool) -> Self {
+        Self { pool }
+    }
+
+    pub fn migratable(&self) -> Arc<dyn RunMigrations> {
+        Arc::new(Postgres::new(self.pool.clone()))
+    }
+}

src/inventory/adapters/output/db/postgres/store_id_exists.rs

@@ -0,0 +1,79 @@
+// SPDX-FileCopyrightText: 2024 Aravinth Manivannan <realaravinth@batsense.net>
+//
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+use super::InventoryDBPostgresAdapter;
+use crate::inventory::application::port::output::db::{errors::*, store_id_exists::*};
+use crate::inventory::domain::store_aggregate::*;
+
+#[async_trait::async_trait]
+impl StoreIDExistsDBPort for InventoryDBPostgresAdapter {
+    async fn store_id_exists(&self, s: &Store) -> InventoryDBResult<bool> {
+        let res = sqlx::query!(
+            "SELECT EXISTS (
+                SELECT 1
+                    FROM cqrs_inventory_store_query
+                WHERE
+                    store_id = $1
+            );",
+            s.store_id(),
+        )
+        .fetch_one(&self.pool)
+        .await?;
+        if let Some(x) = res.exists {
+            Ok(x)
+        } else {
+            Ok(false)
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use uuid::Uuid;
+
+    use super::*;
+
+    #[actix_rt::test]
+    async fn test_postgres_store_exists() {
+        let store_id = Uuid::new_v4();
+        let settings = crate::settings::tests::get_settings().await;
+        settings.create_db().await;
+        let db = super::InventoryDBPostgresAdapter::new(
+            sqlx::postgres::PgPool::connect(&settings.database.url)
+                .await
+                .unwrap(),
+        );
+
+        let store = StoreBuilder::default()
+            .name("store_name".into())
+            .owner("store_owner".into())
+            .address(Some("store_address".into()))
+            .store_id(store_id)
+            .build()
+            .unwrap();
+
+        // state doesn't exist
+        assert!(!db.store_id_exists(&store).await.unwrap());
+
+        sqlx::query!(
+            "INSERT INTO cqrs_inventory_store_query
+                (view_id, version, name, address, store_id, owner)
+            VALUES ($1, $2, $3, $4, $5, $6);",
+            "1",
+            1,
+            store.name(),
+            store.address().as_ref().unwrap(),
+            store.store_id(),
+            store.owner(),
+        )
+        .execute(&db.pool)
+        .await
+        .unwrap();
+
+        // state exists
+        assert!(db.store_id_exists(&store).await.unwrap());
+
+        settings.drop_db().await;
+    }
+}

src/inventory/adapters/output/db/postgres/store_view.rs

@@ -0,0 +1,175 @@
+// SPDX-FileCopyrightText: 2024 Aravinth Manivannan <realaravinth@batsense.net>
+//
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+use async_trait::async_trait;
+use cqrs_es::persist::GenericQuery;
+use cqrs_es::persist::{PersistenceError, ViewContext, ViewRepository};
+use cqrs_es::{EventEnvelope, Query, View};
+use serde::{Deserialize, Serialize};
+use uuid::Uuid;
+
+use super::errors::*;
+use super::InventoryDBPostgresAdapter;
+use crate::inventory::domain::events::InventoryEvent;
+use crate::inventory::domain::store_aggregate::Store;
+
+// The view for a Store query, for a standard http application this should
+// be designed to reflect the response dto that will be returned to a user.
+#[derive(Debug, Default, Serialize, Deserialize)]
+pub struct StoreView {
+    name: String,
+    address: Option<String>,
+    store_id: Uuid,
+    owner: String,
+}
+
+// This updates the view with events as they are committed.
+// The logic should be minimal here, e.g., don't calculate the account balance,
+// design the events to carry the balance information instead.
+impl View<Store> for StoreView {
+    fn update(&mut self, event: &EventEnvelope<Store>) {
+        match &event.payload {
+            InventoryEvent::StoreAdded(val) => {
+                self.name = val.name().into();
+                self.address = val.address().clone();
+                self.store_id = val.store_id().clone();
+                self.owner = val.owner().clone();
+            }
+            _ => (),
+        }
+    }
+}
+
+#[async_trait]
+impl ViewRepository<StoreView, Store> for InventoryDBPostgresAdapter {
+    async fn load(&self, view_id: &str) -> Result<Option<StoreView>, PersistenceError> {
+        let res = sqlx::query_as!(
+            StoreView,
+            "SELECT 
+                name, address, store_id, owner
+             FROM
+                cqrs_inventory_store_query
+            WHERE
+                view_id = $1;",
+            view_id
+        )
+        .fetch_one(&self.pool)
+        .await
+        .map_err(PostgresAggregateError::from)?;
+        Ok(Some(res))
+    }
+
+    async fn load_with_context(
+        &self,
+        view_id: &str,
+    ) -> Result<Option<(StoreView, ViewContext)>, PersistenceError> {
+        let res = sqlx::query_as!(
+            StoreView,
+            "SELECT 
+                name, address, store_id, owner
+             FROM
+                cqrs_inventory_store_query
+            WHERE
+                view_id = $1;",
+            view_id
+        )
+        .fetch_one(&self.pool)
+        .await
+        .map_err(PostgresAggregateError::from)?;
+
+        struct Context {
+            version: i64,
+            view_id: String,
+        }
+
+        let ctx = sqlx::query_as!(
+            Context,
+            "SELECT 
+                view_id, version
+             FROM
+                cqrs_inventory_store_query
+            WHERE
+                view_id = $1;",
+            view_id
+        )
+        .fetch_one(&self.pool)
+        .await
+        .map_err(PostgresAggregateError::from)?;
+
+        let view_context = ViewContext::new(ctx.view_id, ctx.version);
+        Ok(Some((res, view_context)))
+    }
+
+    async fn update_view(
+        &self,
+        view: StoreView,
+        context: ViewContext,
+    ) -> Result<(), PersistenceError> {
+        match context.version {
+            0 => {
+                let version = context.version + 1;
+                sqlx::query!(
+                    "INSERT INTO cqrs_inventory_store_query (
+                        view_id, version, name, address, store_id, owner
+                    ) VALUES (
+                        $1, $2, $3, $4, $5, $6
+                    );",
+                    context.view_instance_id,
+                    version,
+                    view.name,
+                    view.address,
+                    view.store_id,
+                    view.owner,
+                )
+                .execute(&self.pool)
+                .await
+                .map_err(PostgresAggregateError::from)?;
+            }
+            _ => {
+                let version = context.version + 1;
+                sqlx::query!(
+                    "UPDATE
+                        cqrs_inventory_store_query
+                    SET
+                        view_id = $1,
+                        version = $2,
+                        name = $3,
+                        address = $4,
+                        store_id = $5,
+                        owner = $6;",
+                    context.view_instance_id,
+                    version,
+                    view.name,
+                    view.address,
+                    view.store_id,
+                    view.owner,
+                )
+                .execute(&self.pool)
+                .await
+                .map_err(PostgresAggregateError::from)?;
+            }
+        }
+
+        Ok(())
+    }
+}
+
+pub struct SimpleLoggingQuery {}
+
+// Our simplest query, this is great for debugging but absolutely useless in production.
+// This query just pretty prints the events as they are processed.
+#[async_trait]
+impl Query<Store> for SimpleLoggingQuery {
+    async fn dispatch(&self, aggregate_id: &str, events: &[EventEnvelope<Store>]) {
+        for event in events {
+            let payload = serde_json::to_string_pretty(&event.payload).unwrap();
+            println!("{}-{}\n{}", aggregate_id, event.sequence, payload);
+        }
+    }
+}
+
+// Our second query, this one will be handled with Postgres `GenericQuery`
+// which will serialize and persist our view after it is updated. It also
+// provides a `load` method to deserialize the view on request.
+pub type StoreQuery = GenericQuery<InventoryDBPostgresAdapter, StoreView, Store>;

src/inventory/adapters/output/mod.rs

@@ -1,3 +1,5 @@
 // SPDX-FileCopyrightText: 2024 Aravinth Manivannan <realaravinth@batsense.net>
 //
 // SPDX-License-Identifier: AGPL-3.0-or-later
+
+mod db;

src/inventory/application/mod.rs

@@ -2,5 +2,5 @@
 //
 // SPDX-License-Identifier: AGPL-3.0-or-later
 
-mod port;
+pub mod port;
-mod services;
+pub mod services;

src/inventory/application/port/mod.rs

@@ -2,5 +2,5 @@
 //
 // SPDX-License-Identifier: AGPL-3.0-or-later
 
-mod input;
+pub mod input;
-mod output;
+pub mod output;

src/inventory/application/port/output/db/errors.rs

@@ -0,0 +1,15 @@
+// SPDX-FileCopyrightText: 2024 Aravinth Manivannan <realaravinth@batsense.net>
+//
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+use derive_more::Display;
+use serde::{Deserialize, Serialize};
+
+pub type InventoryDBResult<V> = Result<V, InventoryDBError>;
+
+#[derive(Debug, Display, Clone, Serialize, Deserialize, PartialEq, Eq, PartialOrd, Ord)]
+pub enum InventoryDBError {
+    DuplicateCategoryName,
+    DuplicateStoreID,
+    InternalError,
+}

src/inventory/application/port/output/db/mod.rs

@@ -0,0 +1,7 @@
+// SPDX-FileCopyrightText: 2024 Aravinth Manivannan <realaravinth@batsense.net>
+//
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+//pub mod category_exists;
+pub mod errors;
+pub mod store_id_exists;

src/inventory/application/port/output/db/store_id_exists.rs

@@ -0,0 +1,54 @@
+// SPDX-FileCopyrightText: 2024 Aravinth Manivannan <realaravinth@batsense.net>
+//
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+use mockall::predicate::*;
+use mockall::*;
+
+use crate::inventory::domain::store_aggregate::Store;
+
+use super::errors::*;
+#[cfg(test)]
+#[allow(unused_imports)]
+pub use tests::*;
+
+#[automock]
+#[async_trait::async_trait]
+pub trait StoreIDExistsDBPort: Send + Sync {
+    async fn store_id_exists(&self, s: &Store) -> InventoryDBResult<bool>;
+}
+
+pub type StoreIDExistsDBPortObj = std::sync::Arc<dyn StoreIDExistsDBPort>;
+
+#[cfg(test)]
+pub mod tests {
+    use super::*;
+
+    use std::sync::Arc;
+
+    pub fn mock_store_id_exists_db_port_false(times: Option<usize>) -> StoreIDExistsDBPortObj {
+        let mut m = MockStoreIDExistsDBPort::new();
+        if let Some(times) = times {
+            m.expect_store_id_exists()
+                .times(times)
+                .returning(|_| Ok(false));
+        } else {
+            m.expect_store_id_exists().returning(|_| Ok(false));
+        }
+
+        Arc::new(m)
+    }
+
+    pub fn mock_store_id_exists_db_port_true(times: Option<usize>) -> StoreIDExistsDBPortObj {
+        let mut m = MockStoreIDExistsDBPort::new();
+        if let Some(times) = times {
+            m.expect_store_id_exists()
+                .times(times)
+                .returning(|_| Ok(true));
+        } else {
+            m.expect_store_id_exists().returning(|_| Ok(true));
+        }
+
+        Arc::new(m)
+    }
+}

src/inventory/application/port/output/mod.rs

@@ -1,3 +1,5 @@
 // SPDX-FileCopyrightText: 2024 Aravinth Manivannan <realaravinth@batsense.net>
 //
 // SPDX-License-Identifier: AGPL-3.0-or-later
+
+pub mod db;

src/inventory/application/services/add_store_service.rs

@@ -0,0 +1,91 @@
+// SPDX-FileCopyrightText: 2024 Aravinth Manivannan <realaravinth@batsense.net>
+//
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+use derive_builder::Builder;
+use uuid::Uuid;
+
+use super::errors::*;
+use crate::inventory::{
+    application::port::output::db::{errors::InventoryDBError, store_id_exists::*},
+    domain::{
+        add_store_command::AddStoreCommand,
+        store_added_event::{StoreAddedEvent, StoreAddedEventBuilder},
+        store_aggregate::*,
+    },
+};
+
+#[async_trait::async_trait]
+pub trait AddStoreUseCase: Send + Sync {
+    async fn add_store(&self, cmd: AddStoreCommand) -> InventoryResult<StoreAddedEvent>;
+}
+
+pub type AddStoreServiceObj = std::sync::Arc<dyn AddStoreUseCase>;
+
+#[derive(Clone, Builder)]
+pub struct AddStoreService {
+    db_store_id_exists: StoreIDExistsDBPortObj,
+}
+
+#[async_trait::async_trait]
+impl AddStoreUseCase for AddStoreService {
+    async fn add_store(&self, cmd: AddStoreCommand) -> InventoryResult<StoreAddedEvent> {
+        let mut store_id = Uuid::new_v4();
+        let mut store = StoreBuilder::default()
+            .name(cmd.name().into())
+            .address(cmd.address().as_ref().map(|s| s.to_string()))
+            .owner(cmd.owner().into())
+            .store_id(store_id.clone())
+            .build()
+            .unwrap();
+        loop {
+            if self.db_store_id_exists.store_id_exists(&store).await? {
+                store_id = Uuid::new_v4();
+                store = StoreBuilder::default()
+                    .name(cmd.name().into())
+                    .address(cmd.address().as_ref().map(|s| s.to_string()))
+                    .store_id(store_id.clone())
+                    .build()
+                    .unwrap();
+                continue;
+            } else {
+                break;
+            }
+        }
+
+        Ok(StoreAddedEventBuilder::default()
+            .name(store.name().into())
+            .address(store.address().as_ref().map(|s| s.to_string()))
+            .owner(cmd.owner().into())
+            .store_id(store_id.clone())
+            .build()
+            .unwrap())
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    use crate::tests::bdd::*;
+
+    #[actix_rt::test]
+    async fn test_service_store_id_doesnt_exist() {
+        let name = "foo";
+        let address = "bar";
+        let username = "baz";
+
+        // address = None
+        let cmd = AddStoreCommand::new(name.into(), Some(address.into()), username.into()).unwrap();
+
+        let s = AddStoreServiceBuilder::default()
+            .db_store_id_exists(mock_store_id_exists_db_port_false(IS_CALLED_ONLY_ONCE))
+            .build()
+            .unwrap();
+
+        let res = s.add_store(cmd.clone()).await.unwrap();
+        assert_eq!(res.name(), cmd.name());
+        assert_eq!(res.address(), cmd.address());
+        assert_eq!(res.owner(), cmd.owner());
+    }
+}

src/inventory/application/services/errors.rs

@@ -0,0 +1,30 @@
+// SPDX-FileCopyrightText: 2024 Aravinth Manivannan <realaravinth@batsense.net>
+//
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+use derive_more::{Display, Error};
+use log::error;
+use serde::{Deserialize, Serialize};
+
+use crate::inventory::application::port::output::db::errors::InventoryDBError;
+
+pub type InventoryResult<V> = Result<V, InventoryError>;
+
+#[derive(Debug, Error, Display, Clone, Serialize, Deserialize, PartialEq, Eq, PartialOrd, Ord)]
+pub enum InventoryError {
+    DuplicateCategoryName,
+    InternalError,
+}
+
+impl From<InventoryDBError> for InventoryError {
+    fn from(value: InventoryDBError) -> Self {
+        match value {
+            InventoryDBError::DuplicateCategoryName => Self::DuplicateCategoryName,
+            InventoryDBError::DuplicateStoreID => {
+                error!("DuplicateStoreID");
+                Self::InternalError
+            }
+            InventoryDBError::InternalError => Self::InternalError,
+        }
+    }
+}

src/inventory/application/services/mod.rs

@@ -1,3 +1,33 @@
 // SPDX-FileCopyrightText: 2024 Aravinth Manivannan <realaravinth@batsense.net>
 //
 // SPDX-License-Identifier: AGPL-3.0-or-later
+use derive_builder::Builder;
+use mockall::predicate::*;
+use mockall::*;
+
+pub mod errors;
+
+// services
+//pub mod add_category_service;
+pub mod add_store_service;
+
+#[automock]
+pub trait InventoryServicesInterface: Send + Sync {
+    fn add_store(&self) -> add_store_service::AddStoreServiceObj;
+    //   fn add_category(&self) -> add_category_service::AddCategoryServiceObj;
+}
+
+#[derive(Clone, Builder)]
+pub struct InventoryServices {
+    add_store: add_store_service::AddStoreServiceObj,
+    //    add_category: add_category_service::AddCategoryServiceObj,
+}
+
+impl InventoryServicesInterface for InventoryServices {
+    fn add_store(&self) -> add_store_service::AddStoreServiceObj {
+        self.add_store.clone()
+    }
+    //   fn add_category(&self) -> add_category_service::AddCategoryServiceObj {
+    //       self.add_category.clone()
+    //   }
+}

src/inventory/domain/add_store_command.rs

@@ -0,0 +1,79 @@
+// SPDX-FileCopyrightText: 2024 Aravinth Manivannan <realaravinth@batsense.net>
+//
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+use derive_getters::Getters;
+use derive_more::{Display, Error};
+use serde::{Deserialize, Serialize};
+
+#[derive(Debug, Error, Display, Clone, Serialize, Deserialize, PartialEq, Eq, PartialOrd, Ord)]
+pub enum AddStoreCommandError {
+    NameIsEmpty,
+}
+
+#[derive(Clone, Debug, Serialize, Deserialize, Eq, PartialEq, Ord, PartialOrd, Getters)]
+pub struct AddStoreCommand {
+    name: String,
+    address: Option<String>,
+    owner: String,
+}
+
+impl AddStoreCommand {
+    pub fn new(
+        name: String,
+        address: Option<String>,
+        owner: String,
+    ) -> Result<Self, AddStoreCommandError> {
+        let address: Option<String> = if let Some(address) = address {
+            let address = address.trim();
+            if address.is_empty() {
+                None
+            } else {
+                Some(address.to_owned())
+            }
+        } else {
+            None
+        };
+
+        let name = name.trim().to_owned();
+        if name.is_empty() {
+            return Err(AddStoreCommandError::NameIsEmpty);
+        }
+
+        Ok(Self {
+            name,
+            address,
+            owner,
+        })
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_cmd() {
+        let name = "foo";
+        let address = "bar";
+        let username = "baz";
+
+        // address = None
+        let cmd = AddStoreCommand::new(name.into(), None, username.into()).unwrap();
+        assert_eq!(cmd.name(), name);
+        assert_eq!(cmd.address(), &None);
+        assert_eq!(cmd.owner(), username);
+
+        // address = Some
+        let cmd = AddStoreCommand::new(name.into(), Some(address.into()), username.into()).unwrap();
+        assert_eq!(cmd.name(), name);
+        assert_eq!(cmd.address(), &Some(address.to_owned()));
+        assert_eq!(cmd.owner(), username);
+
+        // AddStoreCommandError::NameIsEmpty
+        assert_eq!(
+            AddStoreCommand::new("".into(), Some(address.into()), username.into()),
+            Err(AddStoreCommandError::NameIsEmpty)
+        )
+    }
+}

src/inventory/domain/commands.rs

@@ -0,0 +1,17 @@
+// SPDX-FileCopyrightText: 2024 Aravinth Manivannan <realaravinth@batsense.net>
+//
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+use mockall::predicate::*;
+use serde::{Deserialize, Serialize};
+
+use super::{
+    // add_category_command::AddCategoryCommand,
+    add_store_command::AddStoreCommand,
+};
+
+#[derive(Clone, Debug, Serialize, Deserialize, Eq, PartialEq, Ord, PartialOrd)]
+pub enum InventoryCommand {
+    //AddCategory(AddCategoryCommand),
+    AddStore(AddStoreCommand),
+}

src/inventory/domain/events.rs

@@ -0,0 +1,34 @@
+// SPDX-FileCopyrightText: 2024 Aravinth Manivannan <realaravinth@batsense.net>
+//
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+use cqrs_es::DomainEvent;
+use serde::{Deserialize, Serialize};
+
+use super::{
+    // category_added_event::*,
+    store_added_event::StoreAddedEvent,
+};
+
+#[derive(Clone, Debug, Serialize, Deserialize, Eq, PartialEq, Ord, PartialOrd)]
+pub enum InventoryEvent {
+    //    CategoryAdded(CategoryAddedEvent),
+    StoreAdded(StoreAddedEvent),
+}
+
+//TODO: define password type that takes string and converts to hash
+
+impl DomainEvent for InventoryEvent {
+    fn event_version(&self) -> String {
+        "1.0".to_string()
+    }
+
+    fn event_type(&self) -> String {
+        let e: &str = match self {
+            //           InventoryEvent::CategoryAdded { .. } => "InventoryCategoryAdded",
+            InventoryEvent::StoreAdded { .. } => "InventoryStoredded",
+        };
+
+        e.to_string()
+    }
+}

src/inventory/domain/mod.rs

@@ -1,3 +1,19 @@
 // SPDX-FileCopyrightText: 2024 Aravinth Manivannan <realaravinth@batsense.net>
 //
 // SPDX-License-Identifier: AGPL-3.0-or-later
+
+// aggregates
+//pub mod money_aggregate;
+//pub mod product_aggregate;
+//pub mod stock_aggregate;
+pub mod store_aggregate;
+
+// commands
+//pub mod add_category_command;
+pub mod add_store_command;
+pub mod commands;
+
+// events
+//pub mod category_added_event;
+pub mod events;
+pub mod store_added_event;

src/inventory/domain/store_added_event.rs

@@ -0,0 +1,18 @@
+// SPDX-FileCopyrightText: 2024 Aravinth Manivannan <realaravinth@batsense.net>
+//
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+use derive_builder::Builder;
+use derive_getters::Getters;
+use serde::{Deserialize, Serialize};
+use uuid::Uuid;
+
+#[derive(
+    Clone, Debug, Builder, Serialize, Deserialize, Getters, Eq, PartialEq, Ord, PartialOrd,
+)]
+pub struct StoreAddedEvent {
+    name: String,
+    address: Option<String>,
+    owner: String,
+    store_id: Uuid,
+}

src/inventory/domain/store_aggregate.rs

@@ -0,0 +1,74 @@
+// SPDX-FileCopyrightText: 2024 Aravinth Manivannan <realaravinth@batsense.net>
+//
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+use async_trait::async_trait;
+use cqrs_es::Aggregate;
+use derive_builder::Builder;
+use derive_getters::Getters;
+use serde::{Deserialize, Serialize};
+use uuid::Uuid;
+
+use crate::inventory::application::services::errors::*;
+use crate::inventory::application::services::InventoryServicesInterface;
+
+use super::{commands::InventoryCommand, events::InventoryEvent};
+
+#[derive(
+    Clone, Default, Debug, Serialize, Deserialize, Eq, PartialEq, Ord, PartialOrd, Builder, Getters,
+)]
+pub struct Store {
+    name: String,
+    address: Option<String>,
+    owner: String,
+    store_id: Uuid,
+}
+
+#[async_trait]
+impl Aggregate for Store {
+    type Command = InventoryCommand;
+    type Event = InventoryEvent;
+    type Error = InventoryError;
+    type Services = std::sync::Arc<dyn InventoryServicesInterface>;
+
+    // This identifier should be unique to the system.
+    fn aggregate_type() -> String {
+        "inventory.store".to_string()
+    }
+
+    // The aggregate logic goes here. Note that this will be the _bulk_ of a CQRS system
+    // so expect to use helper functions elsewhere to keep the code clean.
+    async fn handle(
+        &self,
+        command: Self::Command,
+        services: &Self::Services,
+    ) -> Result<Vec<Self::Event>, Self::Error> {
+        match command {
+            InventoryCommand::AddStore(cmd) => {
+                let res = services.add_store().add_store(cmd).await?;
+                Ok(vec![InventoryEvent::StoreAdded(res)])
+            }
+            _ => Ok(Vec::default()),
+            //            InventoryCommand::AddCategory(cmd) => {
+            //                let res = services.add_category().add_store(cmd).await?;
+            //                Ok(vec![InventoryEvent::CategoryAdded(res)])
+            //
+            //            }
+        }
+    }
+
+    fn apply(&mut self, event: Self::Event) {
+        match event {
+            InventoryEvent::StoreAdded(e) => {
+                *self = StoreBuilder::default()
+                    .name(e.name().into())
+                    .address(e.address().as_ref().map(|s| s.to_string()))
+                    .owner(e.owner().into())
+                    .store_id(e.store_id().clone())
+                    .build()
+                    .unwrap();
+            }
+            _ => (),
+        }
+    }
+}