DEV Community: Voy

Google Sheets Everything

Voy — Mon, 23 Nov 2020 03:21:32 +0000

I think Google Sheets is incredible, and I use it for a lot of things. I made a video with some real examples of why I think it is useful.

https://www.youtube.com/watch?v=pT0ygLoSd8E

I hope I inspire some of you (especially being coders!) to give it a go, if you aren't using it already 👋

Generating pair of .jks and .pem certificates.

Voy — Wed, 04 Nov 2020 22:33:08 +0000

I recently run into needing a pair of *.pem and *.jks
self-signed certificates for local TLS verification. After some reading I put together this guide for generating either and converting it to the other.

You can use two approaches:

Generating the TLS Certificates
Ignoring the TLS verification

Note: This guide is based on documentation for an open source library I built recently called IBeam. It is a wrapper working with IBKR Client Portal Web API Gateway. For that reason all example URLs below point to localhost:5000/v1/api/one/user. Modify this URL to whatever routes your server supports.

Generating Certificates

You can generate your own self-signed certificate in two ways:

Using Keytool to generate cacert.jks
Using OpenSSL to generate cacert.pem

Either way you chose, you will then need to convert one certificate into the other. Therefore, you will need both Keytool and OpenSSL to generate your certificates.

Note that you can't generate cacert.jks and cacert.pem independently. You must generate only one certificate first using either method and then convert it into the other format.

Using Keytool

Generate JKS

Keytool is a Java tool shipped with Java Runtime Environment (JRE). It can be found in JRE_ROOT/bin/keytool.

To generate the cacert.jks run:
```
keytool -genkey -keyalg RSA -alias selfsigned \
 -keystore cacert.jks -storepass YOUR_CERTIFICATE_PASSWORD \
 -validity 730 -keysize 2048 
```
Note the YOUR_CERTIFICATE_PASSWORD field. Replace it which certificate password you want to use. You will need to use this same password in later steps.

Optionally, you may want to add additional option to provide Subject Alternative Names (SAN) in order for the certificate to accept requests from your client hosts. For instance, if the server is to be communicated with from two client machines, one with IP address of 10.148.0.0 and one with DNS of my-client.machine.com, your keytool command line should include:
```
-ext SAN=ip:10.147.0.0,dns:my-client.machine.com
```
Upon running command from Step 1, you will be asked the following questions which you may chose to ignore:
- What is your first and last name?
- What is the name of your organizational unit?
- What is the name of your organization?
- What is the name of your City or Locality?
- What is the name of your State or Province?
- What is the two-letter country code for this unit?
Eventually, Keytool will ask for your confirmation, along the lines of:

Is CN=Unknown, OU=Unknown, O=Unknown, L=Unknown, ST=Unknown, C=Unknown correct?

Type yes to continue if the information is correct.
Finally, Keytool will ask you for the key password. You may simply hit return to use the same password as specified in the -storepass flag in Step 1. DO NOT provide a different password than YOUR_CERTIFICATE_PASSWORD specified above.
You should now have the cacert.jks file generated in your current directory.

Convert JKS to PEM

To convert a cacert.jks to cacert.pem file you need to:

Convert cacert.jks to cacert.p12 using Keytool:
```
keytool -importkeystore -srckeystore cacert.jks \
 -destkeystore cacert.p12 -srcstoretype jks -deststoretype pkcs12
```
You will be asked for a new password for cacert.p12, as well as for the original password of cacert.jks. Ensure you use the same password as when generating the cacert.jks.
Convert cacert.p12 to cacert.pem using OpenSSL:
```
openssl pkcs12 -in cacert.p12 -out cacert.pem
```
Again, you will be asked for a new password for cacert.pem, as well as for the original password of cacert.p12. Ensure you use the same password as when generating the cacert.jks and cacert.p12.
You should now have the cacert.pem file generated in your current directory.

You should now have cacert.jks, cacert.p12 and cacert.pem. You will only need the .jks and .pem files. You may delete the redundant cacert.p12 file.

Using OpenSSL

Generate PEM

To generate a cacert.pem using OpenSSL run:
```
openssl req -x509 -days 730 -newkey rsa:2048 \
 -keyout key.pem -out cert.pem
```
Optionally, you may want to add additional option to provide Subject Alternative Names (SAN) in order for the certificate to accept requests from your client hosts. To do so, you must create a san.cnf used as a configuration file for openssl, and add the following to the openssl command line:
```
-config san.cnf
```
Your san.cnf can take multiple forms, yet to support SAN it requires the subjectAltName field. Have a look at this template san.cnf file that you can use as a basis to specify your SANs.

For instance, if the server is to be communicated with from two client machines, one with IP address of 10.148.0.0 and one with DNS of my-client.machine.com, your san.cnf should contain:
```
[alt_names]
IP.1 = 10.148.0.0
DNS.1 = my-client.machine.com
```
You will be asked for a password. You will need to use this same password in later steps.
You should now have key.pem and cert.pem files in your current directory.
Combine key.pem and cert.pem to create cacert.pem:
```
cat key.pem cert.pem > cacert.pem 
```
You can also merge these two files manually if you prefer.
You should now have cacert.pem, key.pem and cert.pem. You will only need the cacert.pem file. You may delete the redundant key.pem and cert.pem files.

PEM to JKS

To convert a cacert.pem to cacert.jks file you need to:

Convert cacert.pem to cacert.p12 using OpenSSL:
```
openssl pkcs12 -export -in cacert.pem -out cacert.p12
```
You will be asked for a new password for cacert.p12, as well as for the original password of cacert.pem. Ensure you use the same password as when generating the cacert.pem.
Convert cacert.p12 to cacert.jks using Keytool:
```
keytool -importkeystore -srckeystore cacert.p12 \
 -srcstoretype pkcs12 -destkeystore cacert.jks
```
Again, you will be asked for a new password for cacert.jks, as well as for the original password of cacert.p12. Ensure you use the same password as when generating the cacert.pem and cacert.p12.
You should now have the cacert.jks file generated in your current directory.

You should now have cacert.pem, cacert.p12 and cacert.jks. You will only need the .jks and .pem files. You may delete the redundant cacert.p12 file.

Use your certificate

cURL

cURL accepts --cacert flag that can be used to pass the certificate. See cURL documentation for more.

curl -X GET "https://localhost:5000/v1/api/one/user" \
  --cacert cacert.pem

Python urllib3

Python urllib3 library allows you to specify a SSL context through which you can specify the location of your certificate.

context = ssl.create_default_context()
context.verify_mode = ssl.CERT_REQUIRED
context.check_hostname = True
context.load_verify_locations('cacert.pem')
urllib.request.urlopen("https://localhost:5000/v1/api/one/user", 
    context=context)

Python requests

Python requests library allows you to set the verify parameter to specify the location of your certificate.

requests.get("https://localhost:5000/v1/api/one/user", 
    verify='cacert.pem')

Ignoring the TLS verification

For debugging and development, you may chose to ignore the TLS verification. This section describes ways of doing so in cURL, Python's urllib3 and requests libraries.

cURL

cURL accepts --insecure or -k flags that can be used to ignore verifying certificates. See [cURL documentation][curl-k] for more.

curl -X GET "https://localhost:5000/v1/api/one/user" -k

Python urllib3

Python urllib3 library allows you to specify an empty SSL context, which effectively will ignore verifying the certificates.

empty_context = ssl.SSLContext()
urllib.request.urlopen("https://localhost:5000/v1/api/one/user", 
    context=empty_context)

Python requests

Python requests library allows you to set the verify parameter to False when making requests, which effectively will ignore verifying the certificates.

requests.get("https://localhost:5000/v1/api/one/user", 
    verify=False)

Hope you guys find this guide useful 👋

Final word: It's a whole another conversation whether it is a good idea to create self-signed certificates and where do they belong. This guide is merely showing you how to create a pair of certificates. It is recommended to verify whether self-signed certificates would be the right choice for your use case.

Becoming a coder #005 - Mentoring my non-coder friend in his programming journey

Voy — Fri, 30 Oct 2020 03:29:40 +0000

Sam has been learning coding since December 2019, we talk every two weeks about his progress. We record our calls thinking that maybe some other beginners would find some of what we discuss useful.

https://www.youtube.com/watch?v=6GKNXRpF_QM

This call was recorded on beginning of July 2020, where we discussed Gulp build system, web app project structure, build systems in general, and understanding what files do what in your application. We also dig into reviewing Sam's portfolio site, speaking of various UI and UX aspects of it, trying to optimise it for potential 'customers' that would review Sam's skills in the future.

Hope some of you may find it useful 👋

Code without a keyboard - serenade.ai

Voy — Wed, 21 Oct 2020 05:17:43 +0000

For real, code using your voice. Serenade allows you to speak your code, instead of typing it. Sit back, relax, and just voice-code away, with a little help of AI. Great for wrist, nerve or repetitive strain injuries preventing you from coding, but also useful for just about anyone wanting to accelerate their workflow using additional voice control. I tried Serenade.ai for a couple of hours and this is my review/tutorial.

Verdict: do give it a shot, it is super cool. So much potential laying in this technology.

https://www.youtube.com/watch?v=Pc-EbY1fRWk

Check Serenade.ai yourself at:

https://serenade.ai/

Hope you find this useful 👋

Becoming a coder #004 - Mentoring my non-coder friend in his programming journey

Voy — Wed, 30 Sep 2020 11:34:03 +0000

Sam has been learning coding since December 2019, we talk every two weeks about his progress. We record our calls thinking that maybe some other beginners would find some of what we discuss useful.

https://www.youtube.com/watch?v=3Cnq8OowRYY

This call was recorded in beginning of July 2020, where we discussed Sam's exercises 3 and 4 - utilising Google Firebase for authentication, file uploading, database storage and more. We also review Sam's roadmap, decide what will be the next steps in his learning path and discuss how to deploy and host the portfolio site he's about to build.

Hope some of you may find it useful 👋

Becoming a coder #003 - Mentoring my non-coder friend in his programming journey

Voy — Fri, 04 Sep 2020 08:34:28 +0000

Sam has been learning coding since December 2019, we talk every two weeks about his progress. We record our calls thinking that maybe some other beginners would find some of what we discuss useful.

https://www.youtube.com/watch?v=324VUHnUaJM

This call was recorded on end of June 2020, where we discussed edabit learning platform, the timeline for applying for jobs, created a Google Document where we list down sam's learning roadmap, Firebase, Redux, Docker, NPM and terminal, Less and Sass, and many more.

Hope some of you may find it useful 👋

Becoming a coder #002 - Mentoring my non-coder friend in his programming journey

Voy — Wed, 26 Aug 2020 12:05:53 +0000

Sam has been learning coding since December 2019, we talk every two weeks about his progress. We record our calls thinking that maybe some other beginners would find some of what we discuss useful.

https://www.youtube.com/watch?v=ub2yXllPqRY

This call was recorded in mid June 2020, where we discuss approaching difficult challenges efficiently, go over his second app built in React - the Coaching Question Generator, Git branching, managing React States, understanding Twitter share button and iframes, and many more. We also discuss edabit and javascript30 platforms to enhance his core JavaScript knowledge.

Hope some of you may find it useful.

Adding large external GIFs to GitHub README.md (over 10MB limit)

Voy — Sat, 22 Aug 2020 11:46:29 +0000

(SKIP TO SOLUTION)

I've recently been adding a GIF to a README.md in my new repo on GitHub, following for instance this cool tutorial on DEV and I was puzzled with this unfortunate choice:

Either I include the GIF in the repo, pumping its size from less than 1MB to 30MB, or
I host the GIF externally, but that only will work with GIFs below 10MB (See this SO answer).

Neither was great, since:

I don't want to needlessly bloat my repo.
My GIF is 1 minute long, 500x500px, 10 FPS, average quality - and still occupies around 30MB.
I could make it shorter, faster, lower resolution, lower FPS, lower quality - all of which are not great either. Is the only choice dropping readability? 😔

However 😮

If GitHub allows the GIFs to be over 10MB if they're currently in a GitHub repo, will it allow me to link to a large GIF located in a different public repository?

I could keep the original repo clean, no large GIFs stored directly inside.
I could have a README.md with a large, good quality GIF.

The answer is YES

Create a new public GitHub repo. I called it voyz/voyz_public
Open terminal, create a new direcotry where you want to locate the repo. For me it was mkdir voyz_public.
Copy-paste the large GIF into that directory.
Once inside, run: (you need installed Git working with GitHub credentials)
1. git init
2. git add .
3. git commit -m "added large GIF"
4. git remote add origin https://github.com/Voyz/voyz_public.git - Naturally, change this address for the URL of your repo.
5. git push
Now that the GIF is hosted on GitHub, its URL can be used in a README.md of another GitHub repo! Go to your new repo, find your GIF and copy its address to the README.md you want to include it in. Works in both Markdown and HTML:

Markdown:



![](https://github.com/Voyz/voyz_public/blob/master/databay_promo_vidA_gif_A03.gif)

HTML:



<img src="https://github.com/Voyz/voyz_public/blob/master/databay_promo_vidA_gif_A03.gif" alt="Databay showcase gif" title="Databay showcase gif" width="500"/>

Hey I can even link to it here on dev.to if I add ?raw=true to the URL! 😊

I tried to look for information whether GitHub is okay with this method, although to no avail. Any feedback on this method most welcome! There are even other repos like this repo with a ton of GIFs so I'm gonna cross my fingers that this isn't unexpected or illegal. Otherwise... quick! upload bloated GIFs while GitHub are asleep!

Hope it helps! 👋
Voy

I just published my first Open Source library in Python and wanted to share it with you guys (video below)

Voy — Fri, 21 Aug 2020 04:26:48 +0000

https://www.youtube.com/watch?v=8XL7d_ehhsA

Databay is a scheduled data transfer interface, facilitating transfer of data from A to B on a scheduled interval. If your project requires custom data transfer, it would make my day if you gave Databay a look.

You can find Databay on GitHub, or its documentation on ReadTheDocs.

Some of Databay’s features are:

Simple, decoupled interface — Easily implement data production and consumption that fits your needs.
Granular control over data transfer — Multiple ways of passing information between producers and consumers.
Asyncio supported — You can produce or consume asynchronously.
We'll handle the rest — scheduling, startup and shutdown, exception handling, logging.
Support for custom scheduling — Use your own scheduling logic if you like.

I’m looking for someone who would like to do some code review on it (it’s relatively small), so if you’d feel like reading some code and helping out - drop me a message. Thanks!

This is the first time I’m publishing an open source library so would love to hear your feedback.

Thanks!
Voy

Becoming a coder #001 - Mentoring my friend in his programming journey

Voy — Wed, 19 Aug 2020 06:06:51 +0000

Sam has been learning coding since December 2019, we talk every two weeks about his progress. We record our calls thinking that maybe some other beginners would find some of what we discuss useful.

https://www.youtube.com/watch?v=TXoDvTJuEb0

This call was recorded on end of May 2020, where we discuss his programming progress, challenges, work hygiene, go over his Weather App built in React, error handling, debugging, datetime and timezones, Git branching, JSX conditionals , try/catching and many more. This is the first recording in the series where we discuss his progress and programming challenges faced on his journey of becoming a junior web developer.

Hope some of you may find it useful.

I'm a coder with 10 years of experience and I made a video about why programming is the coolest job in the world.*

Voy — Wed, 22 Jul 2020 10:30:15 +0000

Some of these things may not be obvious until after a while, so I wanted to share my view after being able to experience this job for a good few years now. Feel free to add whatever benefits you see in coding (or disagree with me wholeheartedly!)

Happy Thursday everyone <3

*IMHO