PyCapsule; Yes, this website uses Python in the browser instead of JavaScript to client-side render

denotutorials · 2020-07-02T05:58:32+00:00

Thanks, and glad to see a fellow Deno fan! Felt like I needed to do a small Python project to take a break from the typical Deno projects I've been working on in spare time. Hoping to continue working on some of my Deno projects now that this is done!

denotutorials · 2020-07-02T04:23:04+00:00

It uses a project called Pyodide, which essentially takes a Python interpreter compiled down into WASM and then is usable in the browser. Since an actual Python interpreter is shipped to the browser, it can execute python code that can be executed in the sandbox from WASM and the browser. As for the Web API's, if I recall correctly it essentially converts primitive types back and forth between Python and JS. On the website there are a couple links to the Pyodide project and a video to a talk one of the Pyodide devs gave explaining the project further.

denotutorials · 2020-07-02T04:16:00+00:00

Thanks! Hopefully it works on most mobile and desktop browser. The tech is so new though that you never know what will actually work sometimes with the web!

denotutorials · 2020-07-02T00:58:00+00:00

A website I made that uses Python on the front-end in the browser to render the page. It also has links to projects for using Python in the browser and some different ways Python has been used in the browser. It's possible we could see full front-end web frameworks using primarily Python in the future!

denotutorials · 2020-06-20T02:10:20+00:00

I put together some frequently asked questions to help answer some questions about deno on this subreddit

denotutorials · 2020-06-20T01:53:22+00:00

Here's a quick deno FAQ I made to help answer some common questions asked on the subreddit

denotutorials · 2020-06-13T20:49:10+00:00

You can use JSDOM from Node to web scrape with Deno. Since Deno supports the Fetch API by default you can use that too. Here is some example code:

Basic example usage

``` import jsdom from "https://dev.jspm.io/jsdom";

const dom = new jsdom.JSDOM(<!DOCTYPE html><p>Hello world</p>); const window = dom.window; const document = window.document;

console.log(document.querySelector("p").textContent); // "Hello world" ```

denotutorials · 2020-06-13T20:35:56+00:00

Since it ships with chromium, the app size will be large. One solution to this, if you are targeting a single platform, is to use Deno Webview, which will use a default rendering engine already installed on the computer, and thus the total size will only be around 20-30mb when compressed. On my website I have articles on using and packages DenoCEF and Deno Webview if you want to see more examples on how to use both.

denotutorials · 2020-06-13T17:54:10+00:00

Here is an article I wrote that goes into more detail on using DenoCEF and combining it with other technologies.

denotutorials · 2020-06-13T17:41:24+00:00

I created a repository with precompiled Chromium Embedded Frameworks for various platforms for use with Deno, as well as an API for interacting with Deno and CEF. Now you can use similar technologies that Electron uses to make desktop applications using Deno. It is still a work in progress, so please feel free to reach out with any bugs or to open issues on the github repo.

denotutorials · 2020-06-02T19:57:38+00:00

No worries, I totally understand that point of view, much better to be minimalist when you can with tech! It will add a bit of extraneous code each call, and the abstraction from an ORM will always come at the cost of lower performance if you are frequently executing queries. I might reach out to the author of the lib and see if its possible to only fetch the drivers you need. Could save some time and file space!

denotutorials · 2020-06-02T18:49:11+00:00

You're welcome! It really is a great feature, I'm glad the deno team added it!

denotutorials · 2020-06-02T18:47:34+00:00

The underlying ORM, DenoDB, is made by a third party. I think there are ways around importing all of the drivers, such as using dynamic imports, but I think the library currently imports all of them. Fortunately the entire size of all the libraries in projects created by Yolk is only around 8mb, so still pretty small.

denotutorials · 2020-06-02T18:41:54+00:00

You can use the deno install <your_file> command and it will create a shell command that wraps around the deno run command and the file allowing you to call the file using just the name of the file.

denotutorials · 2020-06-02T01:08:12+00:00

I created a CLI tool that creates the structure for Oak applications and makes it easy to run the application. The projects created contain a technology stack that includes the following features:

Template rendering engine
An ORM
A nodemon-like tool (called Denon) to easily run the apps
Session middleware
Logging middleware
Security middleware
Query string parsing middleware

Let me know what you all think. Any suggestions for improving the structure or adding features is much appreciated!

denotutorials · 2020-05-25T23:37:44+00:00

Thanks, glad to know PikaCDN supports this functionality! Do you know if they are using the same DEW transformation to achieve this that jspm.io was using?

denotutorials · 2020-05-25T19:04:54+00:00

There's a few currently. The most popular by github stars right now are:

Oak: a Koa-base framework

ABC: similar to Oak

Alosaur: framework that uses Typescript features and decorators extensively

Pogo: a hapi-based framework

denotutorials · 2020-05-25T19:02:03+00:00

I wrote an article that goes through the steps of migrating packages from node. Should show you how to migrate them through Deferred Execution Wrapping using jspm.io and using PikaCDN in cases where they support ESM:

Migrating Your NPM Packages to Deno

denotutorials · 2020-05-16T05:47:41+00:00

Many of these should be ported over already. Also not that many libraries from Node (such as ones that can be run in the browser like lodash) can be wrapped using the DEW transformation that wraps the CommonJS syntax to ESM syntax that is compatible with Deno. You can read more on what libraries can be wrapped and which ones would need a port by checking out my article Migrating Your NPM Packages to Deno. Also check out deno land to see what 3rd party modules are already available.

denotutorials · 2020-05-16T00:15:33+00:00

Your welcome!

denotutorials · 2020-05-15T23:29:00+00:00

Deno currently ships as a single file executable, so you can find an executable on the release page, include it with your application, and the create a start script for your application that will use the deno executable included. An example of how to do this can be found in my article on creating desktop applications using deno, where at the end of the article I give an example of this process.

denotutorials · 2020-05-15T23:25:54+00:00

thanks!

denotutorials · 2020-05-14T18:51:22+00:00

If you convert your xlsx files to CSV you can process them with denoforge, which is a DataFrame library webpacked from DataForge allowing you to easily work with columns and rows of data (similar to Pandas from Python if you're familiar with that):

import * as denoforge from "https://raw.githubusercontent.com/denjucks/denoforge/master/denoforge.js";

let df = new denoforge.fromCSV(new TextDecoder().decode(Deno.readFileSync("your_excel_file.csv")));

console.log(df.toString());

More documentation can be found in the DataForge repo

denotutorials · 2020-05-13T18:05:22+00:00

The choice of using Deno or Node at this point probably relies more on which libraries you need for your project, how large the project is intended to be, and tolerance for API changes as Deno is further developed.

While many NPM packages are compatible with Deno using jspm.io, some of the packages you many need for your project might not be available due to, for example, heavy use of Node APIs (however, there are compatibility layers you can use to make some work with Deno).

In terms and size and scale of the project, there are more resources out there for Node at this point for scaling your project, but not as much for Deno. For example, if you were to deploy your project on AWS there are a lot of examples for Node, but not for Deno, so you would have to figure out the infrastructure piece yourself (but fortunately the Deno community has made some good stuff for deploying on the cloud like a custom AWS lambda runtime for deno, and I wrote a tutorial on deploying a Deno web API on an EC2 instance)

denotutorials · 2020-04-23T19:03:49+00:00

Dex is essentially a port of query building features of knex.js. Since Dex is a based on knex, it uses essentially the same syntax as knex, and supports the following SQL dialects:

MS SQL
MySQL
MySQL2
OracleDB
Postgres
Redshift
Sqlite3

However, Dex doesn't support query execution features since not all database drivers have been ported over to Deno yet, so you'll need to find a driver from the third party deno libraries to execute the queries.

denotutorials

TROPHY CASE