more tests!

birdie_snapshots/memory_store_load_events.accepted

@@ -0,0 +1,23 @@
+---
+version: 1.1.8
+title: memory store load events
+file: ./test/eventsourcing_test.gleam
+test_name: memory_store_load_events_test
+---
+[
+  MemoryStoreEventEnvelop(
+    "92085b42-032c-4d7a-84de-a86d67123858",
+    1,
+    AccountOpened("92085b42-032c-4d7a-84de-a86d67123858"),
+  ),
+  MemoryStoreEventEnvelop(
+    "92085b42-032c-4d7a-84de-a86d67123858",
+    2,
+    CustomerDepositedCash(10.0, 10.0),
+  ),
+  MemoryStoreEventEnvelop(
+    "92085b42-032c-4d7a-84de-a86d67123858",
+    3,
+    CustomerWithdrewCash(5.99, 4.01),
+  ),
+]

birdie_snapshots/sqlite_store_load_events.accepted

@@ -0,0 +1,32 @@
+---
+version: 1.1.8
+title: sqlite store load events
+file: ./test/sqlite_store_test.gleam
+test_name: sqlite_store_load_events_test
+---
+[
+  SerializedEventEnvelop(
+    "92085b42-032c-4d7a-84de-a86d67123858",
+    1,
+    AccountOpened("92085b42-032c-4d7a-84de-a86d67123858"),
+    "BankAccountEvent",
+    "1.0",
+    "BankAccount",
+  ),
+  SerializedEventEnvelop(
+    "92085b42-032c-4d7a-84de-a86d67123858",
+    2,
+    CustomerDepositedCash(10.0, 10.0),
+    "BankAccountEvent",
+    "1.0",
+    "BankAccount",
+  ),
+  SerializedEventEnvelop(
+    "92085b42-032c-4d7a-84de-a86d67123858",
+    3,
+    CustomerWithdrewCash(5.99, 4.01),
+    "BankAccountEvent",
+    "1.0",
+    "BankAccount",
+  ),
+]

gleam.toml

@@ -1,5 +1,5 @@
 name = "eventsourcing"
-version = "0.2.0"
+version = "1.0.0"
 
 # Fill out these fields if you intend to generate HTML documentation or publish
 # your project to the Hex package manager.

src/eventsourcing/memory_store.gleam

@@ -111,7 +111,7 @@ fn load_aggregate(
 
   let #(aggregate, sequence) =
     list.fold(
-      over: commited_events |> list.reverse,
+      over: commited_events,
       from: #(memory_store.empty_aggregate, 0),
       with: fn(aggregate_and_sequence, event_envelop) {
         let #(aggregate, _) = aggregate_and_sequence
@@ -135,7 +135,7 @@ fn commit(
   let eventsourcing.AggregateContext(aggregate_id, _, sequence) = context
   let wrapped_events = wrap_events(aggregate_id, sequence, events)
   let past_events = load_commited_events(memory_store, aggregate_id)
-  let events = list.append(wrapped_events, past_events)
+  let events = list.append(past_events, wrapped_events)
   io.println(
     "storing: "
     <> wrapped_events |> list.length |> int.to_string

test/eventsourcing_test.gleam

@@ -1,6 +1,7 @@
 import birdie
 import eventsourcing
 import eventsourcing/memory_store
+import example_bank_account
 import gleam/int
 import gleam/io
 import gleam/list
@@ -14,10 +15,16 @@ pub fn main() {
 
 pub fn memory_store_execute_test() {
   let mem_store =
-    memory_store.new(BankAccount(opened: False, balance: 0.0), handle, apply)
+    memory_store.new(
+      example_bank_account.BankAccount(opened: False, balance: 0.0),
+      example_bank_account.handle,
+      example_bank_account.apply,
+    )
   let query = fn(
     aggregate_id: String,
-    events: List(eventsourcing.EventEnvelop(BankAccountEvent)),
+    events: List(
+      eventsourcing.EventEnvelop(example_bank_account.BankAccountEvent),
+    ),
   ) {
     io.println_error(
       "Aggregate Bank Account with ID: "
@@ -31,23 +38,23 @@ pub fn memory_store_execute_test() {
   eventsourcing.execute(
     event_sourcing,
     "92085b42-032c-4d7a-84de-a86d67123858",
-    OpenAccount("92085b42-032c-4d7a-84de-a86d67123858"),
+    example_bank_account.OpenAccount("92085b42-032c-4d7a-84de-a86d67123858"),
   )
   |> should.be_ok
   |> should.equal(Nil)
 
   eventsourcing.execute(
     event_sourcing,
     "92085b42-032c-4d7a-84de-a86d67123858",
-    DepositMoney(10.0),
+    example_bank_account.DepositMoney(10.0),
   )
   |> should.be_ok
   |> should.equal(Nil)
 
   eventsourcing.execute(
     event_sourcing,
     "92085b42-032c-4d7a-84de-a86d67123858",
-    WithDrawMoney(5.99),
+    example_bank_account.WithDrawMoney(5.99),
   )
   |> should.be_ok
   |> should.equal(Nil)
@@ -60,49 +67,56 @@ pub fn memory_store_execute_test() {
   |> birdie.snap(title: "memory store")
 }
 
-pub type BankAccount {
-  BankAccount(opened: Bool, balance: Float)
-}
-
-pub type BankAccountCommand {
-  OpenAccount(account_id: String)
-  DepositMoney(amount: Float)
-  WithDrawMoney(amount: Float)
-}
+pub fn memory_store_load_events_test() {
+  let mem_store =
+    memory_store.new(
+      example_bank_account.BankAccount(opened: False, balance: 0.0),
+      example_bank_account.handle,
+      example_bank_account.apply,
+    )
+  let query = fn(
+    aggregate_id: String,
+    events: List(
+      eventsourcing.EventEnvelop(example_bank_account.BankAccountEvent),
+    ),
+  ) {
+    io.println_error(
+      "Aggregate Bank Account with ID: "
+      <> aggregate_id
+      <> " commited "
+      <> events |> list.length |> int.to_string
+      <> " events.",
+    )
+  }
+  let event_sourcing = eventsourcing.new(mem_store, [query])
+  eventsourcing.execute(
+    event_sourcing,
+    "92085b42-032c-4d7a-84de-a86d67123858",
+    example_bank_account.OpenAccount("92085b42-032c-4d7a-84de-a86d67123858"),
+  )
+  |> should.be_ok
+  |> should.equal(Nil)
 
-pub type BankAccountEvent {
-  AccountOpened(account_id: String)
-  CustomerDepositedCash(amount: Float, balance: Float)
-  CustomerWithdrewCash(amount: Float, balance: Float)
-}
+  eventsourcing.execute(
+    event_sourcing,
+    "92085b42-032c-4d7a-84de-a86d67123858",
+    example_bank_account.DepositMoney(10.0),
+  )
+  |> should.be_ok
+  |> should.equal(Nil)
 
-pub fn handle(
-  bank_account: BankAccount,
-  command: BankAccountCommand,
-) -> Result(List(BankAccountEvent), Nil) {
-  case command {
-    OpenAccount(account_id) -> Ok([AccountOpened(account_id)])
-    DepositMoney(amount) -> {
-      let balance = bank_account.balance +. amount
-      case amount >. 0.0 {
-        True -> Ok([CustomerDepositedCash(amount:, balance:)])
-        False -> Error(Nil)
-      }
-    }
-    WithDrawMoney(amount) -> {
-      let balance = bank_account.balance -. amount
-      case amount >. 0.0 && balance >. 0.0 {
-        True -> Ok([CustomerWithdrewCash(amount:, balance:)])
-        False -> Error(Nil)
-      }
-    }
-  }
-}
+  eventsourcing.execute(
+    event_sourcing,
+    "92085b42-032c-4d7a-84de-a86d67123858",
+    example_bank_account.WithDrawMoney(5.99),
+  )
+  |> should.be_ok
+  |> should.equal(Nil)
 
-pub fn apply(bank_account: BankAccount, event: BankAccountEvent) {
-  case event {
-    AccountOpened(_) -> BankAccount(..bank_account, opened: True)
-    CustomerDepositedCash(_, balance) -> BankAccount(..bank_account, balance:)
-    CustomerWithdrewCash(_, balance) -> BankAccount(..bank_account, balance:)
-  }
+  memory_store.load_events(
+    mem_store.eventstore,
+    "92085b42-032c-4d7a-84de-a86d67123858",
+  )
+  |> pprint.format
+  |> birdie.snap(title: "memory store load events")
 }

test/example_bank_account.gleam

@@ -0,0 +1,120 @@
+import decode
+import gleam/dynamic
+import gleam/json
+import gleam/result
+
+pub type BankAccount {
+  BankAccount(opened: Bool, balance: Float)
+}
+
+pub const bank_account_type = "BankAccount"
+
+pub type BankAccountCommand {
+  OpenAccount(account_id: String)
+  DepositMoney(amount: Float)
+  WithDrawMoney(amount: Float)
+}
+
+pub type BankAccountEvent {
+  AccountOpened(account_id: String)
+  CustomerDepositedCash(amount: Float, balance: Float)
+  CustomerWithdrewCash(amount: Float, balance: Float)
+}
+
+pub const bank_account_event_type = "BankAccountEvent"
+
+pub fn handle(
+  bank_account: BankAccount,
+  command: BankAccountCommand,
+) -> Result(List(BankAccountEvent), Nil) {
+  case command {
+    OpenAccount(account_id) -> Ok([AccountOpened(account_id)])
+    DepositMoney(amount) -> {
+      let balance = bank_account.balance +. amount
+      case amount >. 0.0 {
+        True -> Ok([CustomerDepositedCash(amount:, balance:)])
+        False -> Error(Nil)
+      }
+    }
+    WithDrawMoney(amount) -> {
+      let balance = bank_account.balance -. amount
+      case amount >. 0.0 && balance >. 0.0 {
+        True -> Ok([CustomerWithdrewCash(amount:, balance:)])
+        False -> Error(Nil)
+      }
+    }
+  }
+}
+
+pub fn apply(bank_account: BankAccount, event: BankAccountEvent) {
+  case event {
+    AccountOpened(_) -> BankAccount(..bank_account, opened: True)
+    CustomerDepositedCash(_, balance) -> BankAccount(..bank_account, balance:)
+    CustomerWithdrewCash(_, balance) -> BankAccount(..bank_account, balance:)
+  }
+}
+
+pub fn event_encoder(event: BankAccountEvent) -> String {
+  case event {
+    AccountOpened(account_id) ->
+      json.object([
+        #("event-type", json.string("account-opened")),
+        #("account-id", json.string(account_id)),
+      ])
+    CustomerDepositedCash(amount, balance) ->
+      json.object([
+        #("event-type", json.string("customer-deposited-cash")),
+        #("amount", json.float(amount)),
+        #("balance", json.float(balance)),
+      ])
+    CustomerWithdrewCash(amount, balance) ->
+      json.object([
+        #("event-type", json.string("customer-withdrew-cash")),
+        #("amount", json.float(amount)),
+        #("balance", json.float(balance)),
+      ])
+  }
+  |> json.to_string
+}
+
+pub fn event_decoder(
+  string: String,
+) -> Result(BankAccountEvent, List(dynamic.DecodeError)) {
+  let account_opened_decoder =
+    decode.into({
+      use account_id <- decode.parameter
+      AccountOpened(account_id)
+    })
+    |> decode.field("account-id", decode.string)
+
+  let customer_deposited_cash =
+    decode.into({
+      use amount <- decode.parameter
+      use balance <- decode.parameter
+      CustomerDepositedCash(amount, balance)
+    })
+    |> decode.field("amount", decode.float)
+    |> decode.field("balance", decode.float)
+
+  let customer_withdrew_cash =
+    decode.into({
+      use amount <- decode.parameter
+      use balance <- decode.parameter
+      CustomerWithdrewCash(amount, balance)
+    })
+    |> decode.field("amount", decode.float)
+    |> decode.field("balance", decode.float)
+
+  let decoder =
+    decode.at(["event-type"], decode.string)
+    |> decode.then(fn(event_type) {
+      case event_type {
+        "account-opened" -> account_opened_decoder
+        "customer-deposited-cash" -> customer_deposited_cash
+        "customer-withdrew-cash" -> customer_withdrew_cash
+        _ -> decode.fail("event-type")
+      }
+    })
+  json.decode(from: string, using: decode.from(decoder, _))
+  |> result.map_error(fn(_) { [] })
+}