[TOC]
Interview Chat Application
This Project is designed for taking interview online in an interactive way. Interviewer and candidates can talk to each other by messages and interviewer can give some problem and candidates can solve and verify them in one place.
System
Server and User Interface
- Express and Node HTTP
- Socket.IO
- Bootstrap 4
- jQuery
- axios
Engine
UI Modifier
Functionality
Chat Room
This application is support only one chat room. A group of people can join with their username, password and role type. User will be uniquely identify by their username as well as their role also. A user can't join with the name of existing user. Anyone can re-join with their existing credential.
There are two types of user
- Interviewer
- Can see the active user list
- Can see the messages
- Can send messages
- Can see the problem list and solutions
- Can submit a solution of a particular problem
- Candidate
- Can see the active user list
- Can see the messages
- Can send messages
- Can see the problem list and solutions
- Can submit a solution of a particular problem
- Can set and update problem
- First interviewer will be the creator and can create and update problems only
- Creator can only dismiss the chat room
Addition features
- Markdown support (without heading)
- Load previous messages and pinned problem on join
- Join and Leave notification
- Auto copy code line by click on code line number
Problem And Solution
An interviewer can set a problem task on problem area. Only (s)he can edit the problem statement (question only). This problem is actually a programming problem statement. A problem can have one or many test cases or not.
To set a problem an interviewer just fill up the question box. If interviewer don't want to set any test case on a problem (s)he just have to leave the sample test case area. If want to set test case (s)he must to give the test cases in a manner format. And this manner format is in JSON type. Let's assume interviewer set a problem to find out large value from an array of integer; the test case format can be
-
single test case
{ "input" : [10, 20, 5, -10, 100, 59], "output" : 100 } -
multiple test case
[ { "input" : [1,2,3,4], "output" : 4 }, { "input" : [30, 20, 10], "output" : 30 } ]
Sample test cases can't be edited. Only problem statement or question can be edited by the setter only.
Solution Submission
A solution can be submitted by both interviewer and candidate. Currently Python and JavaScript runtime environment is supported.
The solution code should submit in proper to successfully executed. A solution structure is completely dependent on problem statement and sample testcases.
If a problem doesn't have any sample testcases, the solution code execute as a script only. Otherwise a solution code must have a main function and input test case will given by as argument (main(arg)).
Solution structure without sample test cases
Lets assume interviewer set a problem to find out large value of an array of integers without any sample test cases.
JavaScript
Code can have multiple functions, but every console.log() will be ignored. If solution contains multiple functions or statements use a function and place all others functions and statements inside that function and simply return the final result. Assume a solution to find out the max number of an array
function mymainfunc(){
const getMax = arr => {
let l = arr.length;
arr.sort()
return arr[l-1]
}
return getMax([4,1,2,5,0])
}Standard JavaScript library can be use in code. Not node_modules. This above code execution response is 5. If solution has only a single statement then just use that statement. Like mathematical equation.
(10**2)+(20*2)Result will be 140
Python
Python code will executed as python script format. Like to print multiple line just use
print("hello")
print("world")
print(10+20)all the print output will be given as a list of outputs.
[hello , world ,30]
To solve the above problem by python use
def get_max(arr):
c_arr = arr
c_arr.sort()
l = len(arr)
return c_arr[l-1]
my_arr = [4,1,2,3]
result = get_max(my_arr)
print(result)Result will be 4. Standard python library can be used in code.
Solution structure with sample test cases
If a problem has one or multiple test cases, then user code must to submitted in a structured way.
User code must have a main function and every test case input will be given to this main function as argument.
If a problem have single test case then execution engine will call the main function once and return the output. For multiple (assume n) test case engine will call the main function n times and finally return all outputs as an array or list if there is no runtime error.
JavaScript
To solve the problem of find out the large item of an array of integer a JS solution is
const main = arg => {
if (typeof arg === "undefined") {
return -1;
}
if (!Array.isArray(arg)) {
return -1;
}
var arr = arg;
arr.sort((a,b) => a-b);
let l = arr.length;
return arr[l - 1];
}A particular test case input will be given the arg parameter and user code have to explore it and finally return the result. User code must have the main function with arg parameter otherwise engine will be failed to execute the code. The user code can have other function as well. But no variable, constant, function or anything can be named by __results__, __result__, __main__ because those keyword for JS solution.
Python
To solve the problem of find out the large item of an array of integer, A python solution is
def main(arg):
if type(arg) != list:
return -1
arr = arg
arr.sort()
l = len(arr)
return arr[l-1]Scenario is similar as JavaScript. The python solution can have other functions, classes or statements as well with the main function. But no variable, constant, function or anything can be named by __results__, __result__, __main__ because those keyword for JS solution.
Result
If problem doesn't have any test cases then result will be generated as user code return or printed.
If problem has sample test cases then result will be display in a manner format. Case actual output, user code output and comparison status will be return by the engine and display to user interface.
Actual output : 8
Found result : 9
Status : worng