danawoodman

Using Golang templ with the Echo framework

templ is a great view framework but there is no clear documentation (as of writing) showing how to use it with the Echo web framework. This short guide should show you how to set it up:

Install dependencies

Install templ and echo:

go get github.com/a-h/templ

danawoodman

React "Hello World" Examples

Below are a small collection of React examples to get anyone started using React. They progress from simpler to more complex/full featured.

They will hopefully get you over the initial learning curve of the hard parts of React (JSX, props vs. state, lifecycle events, etc).

Usage

You will want to create an index.html file and copy/paste the contents of 1-base.html and then create a scripts.js file and copy/paste the contents of one of the examples into it.

danawoodman

Release golang apps using Github Actions

Want to release a new binary on Github for every new git tag (e.g. v1.2.7)? Here is a simple Github Actions yaml config file that should get you started.

This script will automatically checkout your code, setup the correct version of go as defined in your go.mod file and build your go binary (in this case using a Makefile default target), then upload it to a new Github Release.

# .github/workflows/release.yml
name: Build and release Go Project

danawoodman

Start a web page in kiosk mode on a Raspberry Pi

Install dependencies

Start by installing chromium and unclutter which will hide the cursor on the screen:

sudo apt install -y -no-install-recommends chromium-browser unclutter

danawoodman

How to build a Golang application for a Raspberry Pi

Given a binary at cmd/server/main.go, create a binary at bin/server that is built for a Raspberry Pi:

env GOOS=linux GOARCH=arm GOARM=5 go build -o ./bin/server ./cmd/server/main.go

danawoodman

Setup a system service for the RaspberryPi

If you want to run your own app on a Debian system, like a RaspberryPi, you'll need to build the binary for the given device then setup systemd to run the binary.

Given you have an app called myapp, first create a service file to run your app, say at myapp.service on your local system:

[Unit]
Description=Some description here...
After=network.target

danawoodman

Serving embedded static files with Echo (Golang)

For a project I'm working on, I need to ship a single server binary with all static files embedded and use that for the frontend of the server. The backend has a variety of routes which the frontend calls.

The frontend is a SvelteKit static app built to ./frontend/build. Here is the Echo configuration to get these files serving at the root of the web server:

danawoodman

Allow photo album AND the camera

On Android devices, if you want to create a file input that prompts the user to either choose an image from their photo album or take a picture with their camera, you'll need this basically undocumented capture attribute added to your input's accept property:

<input type="file" accept="image/*;capture=camera" />

danawoodman

await run();

async function run() {
  let loop = 0;

  while (true) {
    loop++;
    console.log("loop:", loop);
    const items = get_items();
    if (!items.length) break;

danawoodman

var fs = require('fs');
var PDFDocument = require('pdfkit');

var pdf = new PDFDocument({
  size: 'LEGAL', // See other page sizes here: https://github.com/devongovett/pdfkit/blob/d95b826475dd325fb29ef007a9c1bf7a527e9808/lib/page.coffee#L69
  info: {
    Title: 'Tile of File Here',
    Author: 'Some Author',
  }
});