From 6d6824f6a79c5207cc92f8d779d628a373bff4ac Mon Sep 17 00:00:00 2001
From: Sourav <souravmohanta4428@gmail.com>
Date: Mon, 25 Mar 2024 19:13:31 +0530
Subject: [PATCH] feat steps 1 2 and 3

---
 package-lock.json  |  4 +++-
 package.json       |  9 +++++----
 sample.csv         |  4 ++++
 src/csvReader.js   | 20 ++++++++++++++++++++
 src/index.js       |  0
 src/queryParser.js | 18 ++++++++++++++++++
 6 files changed, 50 insertions(+), 5 deletions(-)
 create mode 100644 sample.csv
 create mode 100644 src/index.js
 create mode 100644 src/queryParser.js

diff --git a/package-lock.json b/package-lock.json
index 3afaec37f..a6ba782df 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -9,7 +9,6 @@
       "version": "0.1.6",
       "license": "ISC",
       "dependencies": {
-        "csv-parser": "^3.0.0",
         "json2csv": "^6.0.0-alpha.2",
         "xterm": "^5.3.0"
       },
@@ -17,6 +16,7 @@
         "stylusdb-cli": "node ./src/cli.js"
       },
       "devDependencies": {
+        "csv-parser": "^3.0.0",
         "jest": "^29.7.0"
       }
     },
@@ -1573,6 +1573,7 @@
       "version": "3.0.0",
       "resolved": "https://registry.npmjs.org/csv-parser/-/csv-parser-3.0.0.tgz",
       "integrity": "sha512-s6OYSXAK3IdKqYO33y09jhypG/bSDHPuyCme/IdEHfWpLf/jKcpitVFyOC6UemgGk8v7Q5u2XE0vvwmanxhGlQ==",
+      "dev": true,
       "dependencies": {
         "minimist": "^1.2.0"
       },
@@ -2943,6 +2944,7 @@
       "version": "1.2.8",
       "resolved": "https://registry.npmjs.org/minimist/-/minimist-1.2.8.tgz",
       "integrity": "sha512-2yyAR8qBkN3YuheJanUpWC5U3bb5osDywNB8RzDVlDwDHbocAJveqqj1u8+SVD7jkWT4yvsHCpWqqWqAxb0zCA==",
+      "dev": true,
       "funding": {
         "url": "https://github.com/sponsors/ljharb"
       }
diff --git a/package.json b/package.json
index f52103d5c..ef81b73af 100644
--- a/package.json
+++ b/package.json
@@ -4,11 +4,12 @@
   "description": "A minimal SQL based DB based on CSV files. For educational purposes only.",
   "main": "./src/index.js",
   "directories": {
-    "doc": "docs"
+    "doc": "docs",
+    "test": "tests"
   },
   "scripts": {
     "test": "jest",
-    "test:1": "jest --testPathPattern=./tests/step-01",
+   "test:1": "jest --testPathPattern=./tests/step-01",
     "test:2": "jest --testPathPattern=./tests/step-02",
     "test:3": "jest --testPathPattern=./tests/step-03",
     "test:4": "jest --testPathPattern=./tests/step-04",
@@ -38,11 +39,11 @@
   "author": "Chakshu Gautam",
   "license": "ISC",
   "devDependencies": {
+    "csv-parser": "^3.0.0",
     "jest": "^29.7.0"
   },
   "dependencies": {
-    "csv-parser": "^3.0.0",
     "json2csv": "^6.0.0-alpha.2",
     "xterm": "^5.3.0"
   }
-}
\ No newline at end of file
+}
diff --git a/sample.csv b/sample.csv
new file mode 100644
index 000000000..9e7a9fa25
--- /dev/null
+++ b/sample.csv
@@ -0,0 +1,4 @@
+id,name,age
+1,John,30
+2,Jane,25
+3,Bob,22
\ No newline at end of file
diff --git a/src/csvReader.js b/src/csvReader.js
index e69de29bb..b1d92429a 100644
--- a/src/csvReader.js
+++ b/src/csvReader.js
@@ -0,0 +1,20 @@
+const fs = require('fs');
+const csv = require('csv-parser');
+
+function readCSV(filePath) {
+    const results = [];
+
+    return new Promise((resolve, reject) => {
+        fs.createReadStream(filePath)
+            .pipe(csv())
+            .on('data', (data) => results.push(data))
+            .on('end', () => {
+                resolve(results);
+            })
+            .on('error', (error) => {
+                reject(error);
+            });
+    });
+}
+
+module.exports = readCSV;
diff --git a/src/index.js b/src/index.js
new file mode 100644
index 000000000..e69de29bb
diff --git a/src/queryParser.js b/src/queryParser.js
new file mode 100644
index 000000000..2f06cca41
--- /dev/null
+++ b/src/queryParser.js
@@ -0,0 +1,18 @@
+function parseQuery(query){
+    const selectRegex = /SELECT (.+) FROM (.+)/i;
+    const match=query.match
+    (selectRegex);
+
+    if(match){
+        const [,fields,table]=match;
+        return{
+            fields:fields.split(',').
+            map(field=>field.trim()),
+            table:table.trim()
+        };
+    }else{
+        throw new Error('Invalid query format');
+    }
+}
+
+module.exports=parseQuery;
\ No newline at end of file