improve type safety

Author: Moicky

src/transactions/index.ts

@@ -110,9 +110,7 @@ export class Transaction {
 
     const itemKey = this.getItemKey(item, args?.TableName);
 
-    const actions: UpdateAction[] = [
-      { _type: "set", values: { updatedAt: this.updatedAt } },
-    ];
+    const actions: UpdateAction[] = [];
 
     const existingOperation = this.operations[itemKey];
     if (existingOperation && existingOperation._type === "update") {
@@ -195,11 +193,17 @@ export class Transaction {
           ExpressionAttributeNames
         );
 
+        let hasSetUpdatedAt = false;
+
         actions.forEach((action) => {
           switch (action._type) {
             case "set":
               attr.appendBoth(action.values);
 
+              if ("updatedAt" in action.values) {
+                hasSetUpdatedAt = true;
+              }
+
               expressions.set.push(
                 Object.keys(action.values)
                   .map((key) => `${attr.getName(key)} = ${attr.getValue(key)}`)
@@ -209,13 +213,21 @@ export class Transaction {
             case "remove":
               attr.appendNames(action.attributes);
 
+              if (action.attributes.includes("updatedAt")) {
+                hasSetUpdatedAt = true;
+              }
+
               expressions.remove.push(
                 action.attributes.map((key) => attr.getName(key)).join(", ")
               );
               break;
             case "add":
               attr.appendBoth(action.values);
 
+              if ("updatedAt" in action.values) {
+                hasSetUpdatedAt = true;
+              }
+
               expressions.add.push(
                 Object.keys(action.values)
                   .map((key) => `${attr.getName(key)} ${attr.getValue(key)}`)
@@ -225,6 +237,10 @@ export class Transaction {
             case "delete":
               attr.appendBoth(action.values);
 
+              if ("updatedAt" in action.values) {
+                hasSetUpdatedAt = true;
+              }
+
               expressions.delete.push(
                 Object.keys(action.values)
                   .map((key) => `${attr.getName(key)} ${attr.getValue(key)}`)
@@ -234,6 +250,14 @@ export class Transaction {
           }
         });
 
+        if (!hasSetUpdatedAt) {
+          attr.appendBoth({ updatedAt: this.updatedAt });
+
+          expressions.set.push(
+            `${attr.getName("updatedAt")} = ${attr.getValue("updatedAt")}`
+          );
+        }
+
         const joinedExpressions = Object.entries(expressions)
           .filter(([, value]) => value?.length)
           .reduce(

src/transactions/operations.ts

@@ -107,9 +107,18 @@ export class UpdateOperations<U extends DynamoDBItem> {
     this.operation.actions.push({ _type: "add", values: values as any });
     return this;
   }
-  removeAttributes(...attributes: string[]) {
+  removeAttributes(
+    ...attributes: Array<
+      | Exclude<Extract<keyof U, string>, keyof DynamoDBItemKey>
+      | `${string}.${string}`
+      | `${string}.${string}.${string}`
+    >
+  ): UpdateOperations<U> {
     if (attributes.length === 0) return this;
-    this.operation.actions.push({ _type: "remove", attributes });
+    this.operation.actions.push({
+      _type: "remove",
+      attributes: attributes.map(String),
+    });
     return this;
   }
 

test/types.ts

@@ -152,11 +152,30 @@ async function transactionPlayground() {
     SK: string;
     stars: number;
     otherProp: string;
+    nested: {
+      params: number;
+    };
   };
 
-  const res = await new Transaction()
-    .update<TxnItem>({ PK: "User/1", SK: "Book/1" })
-    .set({ otherProp: "test" })
-    .adjustNumber({ stars: 1 })
-    .execute();
+  const item: TxnItem = {
+    PK: "User/1",
+    SK: "Book/1",
+    stars: 0,
+    otherProp: "test",
+    nested: {
+      params: 1,
+    },
+  };
+
+  await putItem(item);
+
+  const txn = new Transaction();
+  txn.update<TxnItem>(item).set({ otherProp: "test" });
+  txn.update<TxnItem>(item).removeAttributes("nested");
+  await txn.execute();
+
+  const updatedItem = await getItem<TxnItem>(item);
+  console.log(updatedItem);
 }
+
+transactionPlayground();