Fixed idempotency issue by first checking if table does not exist

serverless/packages/functions/src/dbutils/get_all_tablenames.ts

@@ -0,0 +1,22 @@
+
+export async function get_all_tablenames() : Promise<string[]> {
+    const AWS = require("aws-sdk");
+    AWS.config.update({region:'us-east-1'});
+    let dynamodb = new AWS.DynamoDB();
+
+    let params = 
+    {
+        ExclusiveStartTableName: null
+    };
+    let tables: string[] = [];
+    while (true) {
+        let response = await dynamodb.listTables(params).promise();
+        tables = tables.concat(response.TableNames);
+
+        if (response.LastEvaluatedTableName === undefined) {
+            break;
+        }
+        params.ExclusiveStartTableName = response.LastEvaluatedTableName;
+    }
+    return tables;
+}

serverless/packages/functions/src/dbutils/table_exists.ts

@@ -0,0 +1,24 @@
+import { get_all_tablenames } from "./get_all_tablenames";
+import { DynamoDBClient, DescribeTableCommand } from '@aws-sdk/client-dynamodb';
+
+export async function table_exists(table_name: string) : Promise<[boolean, string]> {
+    const tableNames: string[] = await get_all_tablenames();
+    const index: number = tableNames.findIndex(storedTableName => storedTableName.endsWith(table_name));
+    return [index !== -1, index !== -1 ? tableNames[index] : ""];
+}
+
+export async function table_attributes_exists(tableExistenceInfo: [boolean, string], table_attributes: object) : Promise<boolean>
+{
+    if (!tableExistenceInfo[0])
+    {
+        /* If table doesn't exist, return false. */
+        return false;
+    }
+    const client = new DynamoDBClient({});
+    const describeTableCommand = new DescribeTableCommand({
+        "TableName": tableExistenceInfo[1]
+    });
+
+    const response = await client.send(describeTableCommand);
+    return true;
+}

serverless/sst.config.ts

@@ -5,7 +5,7 @@ export default {
   config(_input) {
     return {
       name: "dlp-sst-app",
-      region: "us-west-2",
+      region: "us-east-1",
     };
   },
   stacks(app) {

serverless/stacks/AppStack.ts

@@ -1,5 +1,7 @@
 import { Api, Bucket, StackContext, Table } from "sst/constructs";
 import { Bucket as s3Bucket } from "aws-cdk-lib/aws-s3";
+import { DescribeTableCommand } from '@aws-sdk/client-dynamodb';
+import { table_exists, table_attributes_exists } from "../packages/functions/src/dbutils/table_exists";
 
 export function AppStack({ stack }: StackContext) {
   const bucket = new Bucket(stack, "dlp-upload-bucket", {
@@ -11,8 +13,11 @@ export function AppStack({ stack }: StackContext) {
       ),
     },
   });
-  const trainspaceRunTable = new Table(stack, "trainspace-run", {
-    fields: {
+
+  table_exists("trainspace-run").then(exists =>
+  {
+    const tableFieldBody =
+    {
       runId: "string",
       trainspaceId: "string",
       userId: "string",
@@ -22,15 +27,34 @@ export function AppStack({ stack }: StackContext) {
       onnxUri: "string",
       confusionMatrixUri: "string",
       aucRocUri: "string"
-    },
-    primaryIndex: {
-      partitionKey: "runId",
-    },
-    globalIndexes: {
-      "TrainspaceIndex": { partitionKey: "trainspaceId", sortKey: "timestamp"},
-      "UserIndex": {partitionKey: "userId"}
-    },
+    };
+
+    table_attributes_exists(exists, tableFieldBody).then(tableAttributesExists => {
+      if (!tableAttributesExists) {
+        new Table(stack, "trainspace-run", {
+          fields: {
+            runId: "string",
+            trainspaceId: "string",
+            userId: "string",
+            timestamp: "string",
+            resultCsvUri: "string",
+            modelPtUri: "string",
+            onnxUri: "string",
+            confusionMatrixUri: "string",
+            aucRocUri: "string"
+          },
+          primaryIndex: {
+            partitionKey: "runId",
+          },
+          globalIndexes: {
+            "TrainspaceIndex": { partitionKey: "trainspaceId", sortKey: "timestamp"},
+            "UserIndex": {partitionKey: "userId"}
+          },
+        });
+      }
+    });
   });
+
   const api = new Api(stack, "Api", {
     authorizers: {
       FirebaseAuthorizer: {
@@ -69,9 +93,6 @@ export function AppStack({ stack }: StackContext) {
       api.getFunction("GET /datasets/user/{type}")?.functionName ?? "",
     GetUserDatasetColumnsFunctionName:
       api.getFunction("GET /datasets/user/{type}/{filename}/columns")
-        ?.functionName ?? "",
-    TrainspaceRunTableName: {
-      value: trainspaceRunTable.tableName
-    }
+        ?.functionName ?? ""
   });
 }