Create table or collection command, standalone dev environment

docker-compose.yml

@@ -0,0 +1,10 @@
+version: '3.8'
+services:
+  mongodb:
+    image: mongo:6-jammy
+    ports:
+      - '27017:27017'
+    volumes:
+      - dbdata6:/data/db
+volumes:
+  dbdata6:

sample/index.js

@@ -0,0 +1,33 @@
+import {SqlToNoSql} from "../dist/index.mjs"
+
+const runner = new SqlToNoSql({
+  srcDBtype: "postgresql",
+  destDBtype: "mongodb",
+  connection: "mongodb://localhost:27017/admin",
+});
+
+
+
+const main = async () => {
+  // Create a users table
+  const createUsers = await runner.run(
+    "create users"
+  );
+
+
+  const resp = await runner.run(
+    "select * from users where email = [email protected]",
+  );
+
+  console.log(resp);
+  return resp;
+}
+
+main()
+/** ☝️ [{
+    _id: new ObjectId("622f07d56852c662cb8b953b"),
+    role: 'admin',
+    name: 'Arif Hossain',
+    email: '[email protected]',
+    __v: 0
+  }]*/

src/index.mts

@@ -1,4 +1,4 @@
-import { MongoClient } from "mongodb";
+import { MongoClient, MongoServerError } from "mongodb";
 
 import { mappings } from "./config/mapping.mjs";
 import { parseQuery } from "./utils/parser.mjs";
@@ -22,46 +22,68 @@ export class SqlToNoSql {
 
     const q = parseQuery(query);
 
-    const filters: {
-      [key: string]: {
-        [operator: string]: string | number;
-      };
-    } = {};
-
-    // Convert parsed filters to MongoDB query
-    q.filters?.forEach((filter) => {
-      const { column, operator, value } = filter;
-
-      if (!filters[column]) {
-        filters[column] = {
-          [mappings["mongodb"]["operators"][operator]]: value,
+    if (q.command === "select"){
+      const filters: {
+        [key: string]: {
+          [operator: string]: string | number;
         };
+      } = {};
+
+      // Convert parsed filters to MongoDB query
+      q.filters?.forEach((filter) => {
+        const { column, operator, value } = filter;
+
+        if (!filters[column]) {
+          filters[column] = {
+            [mappings["mongodb"]["operators"][operator]]: value,
+          };
+        }
+      });
+
+      const mongoQuery = {
+        collection: q.table,
+        [q.command]: mappings["mongodb"]["commands"][q.command],
+        query: filters,
+      };
+
+      try {
+        if (!this.client) {
+          this.client = await connect(this.config.connection);
+          await this.client.connect();
+        }
+
+        const db = this.client.db();
+        const collection = db.collection(mongoQuery.collection);
+
+        const data = await collection[mongoQuery[q.command]](
+          mongoQuery.query,
+        ).toArray();
+
+        return data;
+      } catch (err) {
+        console.error(err);
+        throw Error("Something went wrong!");
       }
-    });
-
-    const mongoQuery = {
-      collection: q.table,
-      [q.command]: mappings["mongodb"]["commands"][q.command],
-      query: filters,
-    };
-
-    try {
-      if (!this.client) {
-        this.client = await connect(this.config.connection);
-        await this.client.connect();
+    } else if (q.command === "create") {
+      try {
+        if (!this.client) {
+          this.client = await connect(this.config.connection);
+          await this.client.connect();
+        }
+
+        const db = this.client.db();
+        const result = await db.createCollection(q.table);
+        console.log("Mongo result", result);
+        return result;
+      } catch (err) {
+        if (err instanceof MongoServerError) {
+          if (err.codeName === 'NamespaceExists'){
+            console.error("Collection already exists: " + q.table)
+          }
+        } else {
+          throw Error("Something went wrong!");
+        }
       }
-
-      const db = this.client.db();
-      const collection = db.collection(mongoQuery.collection);
-
-      const data = await collection[mongoQuery[q.command]](
-        mongoQuery.query,
-      ).toArray();
-
-      return data;
-    } catch (err) {
-      console.error(err);
-      throw Error("Something went wrong!");
     }
   }
 }

src/types/sql.mts

@@ -5,7 +5,7 @@ interface filterType {
 }
 
 export interface ParsedSqlType {
-  command: "select";
+  command: "select" | "create";
   table: string;
   columns: string[];
   filters: filterType[] | null;

src/utils/parser.mts

@@ -2,6 +2,8 @@
 
 import { ParsedSqlType } from "types/sql.mjs";
 
+const supportedCommands = ["select", "create"];
+
 export const parseQuery = (query: string): ParsedSqlType => {
   const parsedQuery: ParsedSqlType = {
     command: "select",
@@ -13,32 +15,36 @@ export const parseQuery = (query: string): ParsedSqlType => {
   const [command, ...rest] = query.split(" ");
 
   const lowerCaseCommand = command.toLowerCase();
-  if (lowerCaseCommand !== "select") {
-    throw new Error("Only select queries are supported");
+  if (supportedCommands.indexOf(lowerCaseCommand) < 0) {
+    throw new Error(`Only following commands are supported: ${supportedCommands} given: ${lowerCaseCommand}`);
   }
   // parsedQuery.command = command;
-
-  const fromIndex = rest.findIndex((word) => word.toLowerCase() === "from");
-  if (fromIndex === -1) {
-    throw new Error("Invalid query, missing FROM keyword");
+  if (lowerCaseCommand === "select"){
+    const fromIndex = rest.findIndex((word) => word.toLowerCase() === "from");
+    if (fromIndex === -1) {
+      throw new Error("Invalid query, missing FROM keyword");
+    }
+    parsedQuery.table = rest[fromIndex + 1];
+    parsedQuery.columns = rest.slice(0, fromIndex);
+
+    const whereIndex = rest.findIndex((word) => word.toLowerCase() === "where");
+    if (whereIndex !== -1) {
+      parsedQuery.filters = [
+        {
+          column: rest[whereIndex + 1],
+          operator: rest[whereIndex + 2] as "=",
+          // to handle string and number values
+          value:
+            Number(rest[whereIndex + 3]) ||
+            // remove quotes from string values
+            String(rest[whereIndex + 3]).replace(/^'(.*)'$/, "$1"),
+        },
+      ];
+    }
+  } else if (lowerCaseCommand === "create") {
+    parsedQuery.command = "create";
+    const table_name = rest[0];
+    parsedQuery.table = table_name;
   }
-  parsedQuery.table = rest[fromIndex + 1];
-  parsedQuery.columns = rest.slice(0, fromIndex);
-
-  const whereIndex = rest.findIndex((word) => word.toLowerCase() === "where");
-  if (whereIndex !== -1) {
-    parsedQuery.filters = [
-      {
-        column: rest[whereIndex + 1],
-        operator: rest[whereIndex + 2] as "=",
-        // to handle string and number values
-        value:
-          Number(rest[whereIndex + 3]) ||
-          // remove quotes from string values
-          String(rest[whereIndex + 3]).replace(/^'(.*)'$/, "$1"),
-      },
-    ];
-  }
-
   return parsedQuery;
 };