Saptak's Blog Posts

In The Heat of Code or CodeHeat, as it is famously known right now started when Mario Behling started a discussion with me about how to encourage continuous contribution to projects by FOSSASIA even after GSoC. The scenario was most of the time students or participants stopped contributing after Google Summer of Code ended because there wasn't much incentive or profit of their's in continuing with the projects. So we decided to give people a reason to continue. In fact why just continue? Why not get completely new contributors??? And without distinguishing whether they were in university or school or working professionals. So we got others in FOSSASIA team also to drafting the idea into a proper event. And thus began CodeHeat. The official announcement was made in September 20th. The coding started on September 25th. I was to be a mentor in the Open Event Organizer Server project. And the registrations started coming.

We had a huge number of registrations but sadly there were very few contributions in the Open Event Organizer Server project. Most of the participants were more interested and enthusiastic in contributing to android app development and our project got a little less attention. Nonetheless, I and Niranjan continued our own contributions and reviewed occassional pull requests we received. It was almost end of November and though CodeHeat was going great I wasn't very happy as a mentor since our project didn't get much contributors.

Then in the beginning of December few of my friends from college asked me about codeheat and said they were interested in Python. I was delighted and introduced them to Open Event Organizer Server project. Soon there were participants from other colleges as well. We started getting more and more contributions. Then there were 2 participants -  Shubham Padia and Medozonuo who were not only contributing but were almost competing with each other. The result of their competition was we got huge number of awesome code contributions from both of them in all areas from frontend to backend to even database improvements.

From implementing the entire discount and access code system to providing more options and making it more customizable for CFS to solving tons of frontend bugs and export functionality, I and Niranjan almost started having a hard time reviewing their PRs since there were tons of them. I was delighted. The project was nearing release more and more and it was reaching a stage where we can actually make an attempt to use it in production. I and Niranjan often discussed how we hoped these 2 make to the top ten in CodeHeat. It was almost like reliving GSoC from a mentor's perspective.



Finally it was result time. Though it would be wrong to say I was nervous but I surely was excited to know whether any of the contributors of open event organizer server project made it to the top ten. To my utter happiness not only did they make to top ten but Shubham Padia and Medozonuo made it to the top 3. I was really happy for them since they truly deserved it. I guess Niranjan would agree with me in saying that we truly loved mentoring them. It wasn't like they knew each and everything but they picked up stuff pretty quickly and showed their contribution in all aspects of the code. Also, we were later able to get their help in reviewing other's code which was really helpful for me and Niranjan.

It was a really wonderful experience, mentoring in CodeHeat, reviewing PRs day and night, sharing knowledge with others. I simply loved the experience. The icing on the cake was 2 of the top 3 were contributors to open event organizer project. A lot many mentoring experiences are on the queue and I am really looking forward to them.

I know I am pretty early to write this blog for ScienceHackDay India 2017, but got some free time I suppose.

Last year after completing GSoC successfully with FOSSASIA, my main aim with all the newly earned money was to attend conferences and meet like-minded people over hackdays and meetups. It started with PyCon India. Now it was time for ScienceHackDay, India...

So, as soon as I came to know about Science Hack Day, I had my tickets booked and ready to leave. To be honest, I had very little what's going to happen, who all were coming and all. I was just trying to hide my introvert self and get to meet new people.




Day 1:

The journey from Allahabad to Belgaum was pretty hectic. A train from Allahabad to New Delhi, then a flight from New Delhi to Mumbai and then a flight from Mumbai to Belgaum. But after landing in airport itself, it lifted up my mood after the tiring journey. Small hillocks all around and not a metro city. What can be better for a quick getaway? On the way, I came to know Sayan Chowdhury and Kushal Das were also going to be there. Little did I know that I was actually going to share room with them. The first word that came to my mind on reaching the destination was "WOW". It was pretty outside city, no usual cacophony, and the resort was awesome. The place where I was staying was designed in the form of a lake house.



So after reaching, I was really excited to meet Hong Phuc Dang. She is the founder of FOSSASIA and I have been associated with FOSSASIA for quite some time now, and heard a lot about her and also talked with her online, but now was the time. I won't lie, I was a little nervous. But then she came and casually asked whether I wanted to go for kayaking with them. I was like, REALLY!! Well, why not... She was so friendly and nice, I felt a little embarrassed to feel nervous actually. And yes, also realised I was terrible in kayaking...

Then, over dinner, got to meet some really really really awesome people. Everytime Kushal or Sayan introduced me to someone or I talked with someone, it was like WOW, his/her work is so cool.......

Day 2:

Started with inauguration. Things were going pretty well until Hong Phuc introduced me as a senior software developer in FOSSASIA to the crowd. I was like, was that my name?? Surely??? Needed someone to pinch me at that time actually. After the inauguration, it was hack time. So the thing was there were teams to be formed with one of who visited the hack day from outside and the participants. I was the only guy planning to do something with software, while others were trying to do hardware stuff ( the only hardware hack I can do is light a LED ). So I was joined by some interested participants and I started giving them a brief introduction about chrome extension and the plans of the hack. So the hacks continued and I kept peeping into other's works... It was all so confusing (that's the word I feel for hardwares, always....)



Evening we had lightning talks. I gave a lightning talk on Open Event Orga Server, my Google Summer of Code project with FOSSASIA. There were many other projects and new things that I came to know over those lightning talks. And and and and.... Praveen Patil did a laser show to explain Physics!!! I am so jealous of the students whom he teaches Physics to....



Day 3:

Wrap up day... Time to complete the project... And the others in my team didn't turn up. Weird experience but then Hong Phuc said you are the only software hack, so you are doing. That was all the motivation needed. I quickly started working on my chrome extension. It was a text to speech conversion of any wikipedia page in any language. Then it was time for presentation. I was nervous as always but didn't even think about winning so wasn't that tensed after all...



People were showing their hacks and I was like I should have been a participant and joined their team. It was result time and I was just chatting with Sayan about some random things I don't remember now. And suddenly, out of the blue, my project was declared as Best Education Hack. I was shocked, happy, surprised...

Later on, Rahul Prabhukhanolkar told us about bat detectors. It was pretty interesting to know that there were actually bats present there also and we didn't know at all.

Time to return

So it was time to return. Had a flight in the morning. So had breakfast and left for airport with Praveen. Entered airport, and I MISSED THE FLIGHT.... Seemed the flight was preponed and the airlines was ignorant enough to not inform us in anyway... Praveen was helpful enough. Took me for a small tour in his car, had some awesome dinner and then caught a bus to Pune. From Pune, got a flight to New Delhi and then a train from New Delhi. All tired, but full of excitement.

My purpose was fulfilled... Got to meet some awesome people... More than coding and tech goals, I got some life goals after listening to their experiences... Looking forward to meet them again...

PyCon India is one of the best experiences I have had in recent past. PyCon India this year was held in New Delhi from 23rd September to 25th September, 2016. Three days filled with learning, interaction, meeting like minded people; couldn't have asked for anything more. The entire was one of python and development and I loved it.

Day 1 - Devsprint

Day 2 - Volunteering Experience

Day 3 - Last Day

There are certain fields in form where instead of a single value, we need an array of values to be stored. This are fields under the same category but having multiple elements, e.g., Tracks, Session Types, Microlocations, Sponsors, Social Links and similar such fields. Now as we know the way of doing this using simple html is provide the <input> tag with property “name” as “<field_name>[]”. So suppose we want to save the names of the mutliple tracks, we will have something like this

But the problem begins when you want to update name of a particular element (in this case Track). How to do it? Should we delete and create entries again? That doesn’t sound too good, does it? So what should we do? Let’s see….

Delete. Save.

So as said above, one of the easiest way of updating is when you get the updated input, you delete all the previous entries and save the new data again to the DB. Well that works perfectly fine with some fields such as Sponsors because no other table have dependency on Sponsors table. But what if another table has a foreign key constraint on the table you are updating.
For example, Sessions depend on the Tracks table because a session belongs to a particular table. So what happens when we delete a track and then save it again to DB to update. Well, the old track with the actual track_id is lost, which means the session is no more linked to any track or may in fact even be deleted all together depending on your constraint. All in all its a complete disaster!!
Thus, as anyone can say, this is not a good practice. So what should we do?

Use ID to Update

Well, this might seem obvious that we need an ID to edit or update the information, but how do we use tor submit the ID so that it can be used to update data in backend.
On way of doing it is hidden input field. You can use an input field which won’t be shown to the user, but contains the ID(e.g. Track ID) which is submitted on the form submit. At the backend you can get the object(Track) using this ID(Track ID), update the values such as name, color, etc., and then save back to the DB. This is pretty effective.

Another way of doing is before the form is submitted, you can send the array of IDs as a data appending to the already existing form data using Javascript. This is also a really effective way of doing.
However there is a small security issue in this one. One might modify the value of hidden input field using javascript hacks or inspect elements which would then actually modify a separate Track which they might not have permission to edit. So, how do we take care of this?
For this we not only filter the data from Table based on the Track ID(or any other ID) but also with the event ID. How this makes editing secure and correctly based on permissions is, users can only edit events in which they have write access. So if they send a POST or PUT request with a particular event ID, they must have permission to edit informations of that event. And since we also filter using event ID so the Tracks ( or any such fields like Session Type) that he can edit will belong to this event which he has permission to write. So this way we can handle the security issue in the backend.
One last thing to take care in backend is suppose we remove a Track while updating which was previously there. So we need to delete this track from the DB. So we make a check whether there was so Track ID presently which is no more present in the form data requested and delete all such entries from the DB.

One of the important features while creating server side code for some website/ web application is sending emails. But how do we send emails. There are different ways and packages using which you can setup SMTP ports and send emails. So why specifically sendgrid? Because along with SMTP relay, sendgrid also allows you to send emails using its Web API which makes work much easier. Here, we will discuss about using Web API.



SendGrid’s Web API sends mail via HTTP. Your server sends a message to SendGrid, and receives either a 250 message, indicating that the message was accepted by the receiving server, or a 400 or 500 message, indicating that something is wrong, prohibiting us from processing the request.
When everything is packaged correctly, SendGrid can process the request and then send it to the intended recipient’s ISP that responds with either a 250 message or a 500 message of their own, informing SendGrid whether or not the message was received. This process is more similar to putting your package in the mailbox and letting the post office review its information and deliver it for you.
Some sample requests:
Authentication:

 curl -X "GET" "https://api.sendgrid.com/v3/templates" -H "Authorization: Bearer Your.API.Key-HERE" -H "Content-Type: application/json"

Requests:

POST https://api.sendgrid.com/v3/templates/ HTTP/1.1
Content-Type: application/json
{
"name": "new template name"
}

Responses:

HTTP/1.1 200 OK
Content-Type: application/json
{
"foo": "bar",
}

Errors:
You can go through the various errors from this link: https://sendgrid.com/docs/API_Reference/Web_API_v3/How_To_Use_The_Web_API_v3/errors.html

An example request for email is:
Request:-

POST https://api.sendgrid.com/v3/mail/send HTTP/1.1

Request body:-

{
"personalizations": [
{
"to": [
{
"email": "john@example.com"
}
],
"subject": "Hello, World!"
}
],
"from": {
"email": "from_address@example.com"
},
"content": [
{
"type": "text",
"value": "Hello, World!"
}
]
}

Response:-

{
HTTP/1.1 202
}