This git repo contains an incomplete C program, whose goal is to checks that a website is alive. If it is, the C program will call a script.
If you are doing this at the Wink office, your workstation is already set up. Please skip to the next section. If you're doing this on your own, you'll need to install libcurl on your machine:
- For Ubuntu:
sudo apt-get update && sudo apt-get install libcurl4-openssl-dev. - For OSX: you're already good to go with libcurl (albeit with an outdated version).
This program is currently incomplete. There are several necessary steps, written out below, to make this program meet requirements. Complete as much as possible during the allotted time, with a preference for getting something compiling and working instead of making it perfect. You will probably not complete the entire task in the allocated time (and that's ok!). You may use any online resources you would like. Any changes or improvements to the program are welcomed, or you may simply add "TODO" comments if you spot something you would want to fix but do not have time to fix during this interview.
This program is stored in a git repository -- feel free to make use of any git features (e.g. stash, diff) if you would like to. At several points, you will be asked to make a commit. You may make additional commits at any time, if you desire. Generally, anything is allowed during this exercise, unless an instruction specifically disallows it.
Take a look at the C files in the src/ directory. The first step is to modify the main() function to take a command line argument and print it back to stdout. At this time, do not worry about implementing any other functionality.
At the end of this step, you should be able to generate the following output:
$ cd src/
$ make
$ ./websiteChecker "hello world"
hello world
Please make a commit at the end of this step, with the title "Completed step 1: command line echo"
The checkWebsite() function in src/websiteChecker.c needs to be completed, to match the comment above it.
Additionally, the main() function in the program should be modified to accept the first parameter from the command line as the URL, and return the value of the call to checkWebsite(). At this time, do not worry about the other functions described in the comment above main().
Hints:
libcurlis installed on this system, if you wish to use it, though you may use any implentation you would like, including installing other libraries.- You may need to modify the Makefile to get your program to compile, when using outside libraries.
At the end of this step, you should be able to generate the following output:
$ cd src/
$ make
$ ./websiteChecker "example.com"
$ echo $?
0
$ ./websiteChecker "thisIsNotARealWebsite.noTLD"
$ echo $?
1
Please make a commit at the end of this step, with the title "Completed step 2: checkWebsite() function"
Complete the main() function as described in the comment above it, making use of the execCommand() function.
At the end of this step, you should be able to generate the following output:
$ cd src/
$ make
$ ./websiteChecker example.com "echo hello world"
hello world
$ echo $?
0
$ ./websiteChecker thisIsNotARealWebsite.noTLD "echo hello world"
$ echo $?
1
Please make a commit at the end of this step, with the title "Completed step 3: websiteChecker program"
The program is running great right now, but you have a small problem: sometimes, the script that you want to call takes a long time to run. Or, sometimes, you don't want to wait while the request times out when the website is down.
$ time ./websiteChecker "example.com" "sleep 5"
real 0m5.144s
user 0m0.000s
sys 0m0.000s
Sure, the user could run your script in the background by appending & to the command in their shell. But instead, let's do it for them as part of this program.
At the end of this step, you should be able to generate the following output:
$ rm ./testFile
$ time ./websiteChecker "example.com" "sleep 1; touch $PWD/testFile"
real 0m0.004s
user 0m0.000s
sys 0m0.000s
$ sleep 2
$ ls ./testFile
./testFile
$ rm ./testFile
Please make a commit at the end of this step, with the title "Completed step 4: deamonized program"
Please add a test to the test/ directory. You may use any testing framework you choose (or none at all). Please also modify the Makefile to compile and run these tests when calling make test-build and make test-run, respectively. If you are running out of time, please document your intentions with comments in the code.
At the end of this step, you should be able to run make test-build and make test-run.
Please make a commit at the end of this step, with the title "Completed step 5: testing"