UI Improvements & Refactoring

The biggest UI improvement is the use of the prompui package for consuming user input. It's more interactive and performs dynamic validation.

The UI now allows the user to select the encryption type from a list if the encryption option is invalid or an empty option is specified with -enc=. As before, if no encryption option is given, it defaults to WPA2 and the user is not prompted for the encryption type. I've tried to make these improvements without breaking the old UI flow (yet). One difference is invalid encryption protocols were allowed, but now they are limited to valid types.

The main package has been mostly refactored. The highlights include:

• Extraction of code to smaller functions to improvement maintainability, readability and hopefully to help accommodate future unit tests.
• Move code in main to a new run function that returns an exit code. (Helps with future unit tests)
• Remove the use of all global variables except injected version.
• DRY the code.
  • SSID/password descriptions
  • .png extension
  • Validation code
• Improve user facing text consistency.
• Consistent use of error returns.
• Validation of SSID maximum length.
• Validation of encryption option.
• Some unit test coverage.

The core package now contains the type EncryptionType to help limit the input into the API and make the strings consistent. This particular implementation isn't ideal but works for now.

Minor edits made to the README, mostly to conform to markdownlint.

Note this PR changes the API a bit, but since it's a v0.x.x series of releases, I've assumed that's ok. The encryption protocol has changed from a type of string to EncryptionProtocol for both NewConfig and the Config struct.

Unit testing will require a bit of dependency injection but before going through that, it'll be good to see how far this PR goes since I know it's unsolicited.

Greetings! Per my comment on reddit regarding a bug I found today:

There seems to be a bug when using spaces in either the network name or the password:

$ go run github.com/reugn/wifiqr/cmd/wifiqr@latest
Enter the name of the wireless network (SSID):
one two three
Enter the network key (password):

(qr code omitted for brevity)

bash-5.1$ three
bash: three: command not found
bash-5.1$ 

Notice that it did not ask me for the password. Scanning the generated QR code shows that it used one as the SSID and two as the password.

Various Updates

• Update Cobra from v1.2.1 to v.1.5.0
  • Because Viper is no longer pulled in, it should reduce the dependency tree
• Update Go 1.18.x for building and testing
• Update workflow actions to latest versions
  • actions/checkout@v3
  • actions/setup-go@v3
  • goreleaser/goreleaser-action@v3

This is a proposal in the form of a PR to migrate the CLI from the standard library to the Cobra package under the Apache License 2.0. Cobra is used by Kubernetes, the GitHub CLI, GoReleaser and many other popular projects.

I can think of several benefits for this project with this migration:

• Standard and familiar CLI interface like those of the projects mentioned above.
• Long (--ssid) and short (-s) option formats.
• Built in help output.
• Automatic version option.
• A more full featured flags library in general.

A couple of reasons why you may not want to migrate:

• Dragging yet another non-standard library into this project.
• Larger executable (from about 3 mb to about 3.5 mb).
• You have a problem with the Apache License 2.0.

Command Options

To transition to the combined long and short options, I've changed some of the options. These are simply my suggestions and should be carefully reviewed to ensure it's what you want. I can make any changes here that you'd like.

Flag usage from the CLI changes a bit because of the long and short options.

The changes are:

• -file is now --output and -o which seems to be consistent with other utilities
• -enc is now --protocol and -p because it is the protocol being specified
• The short form of --ssid is -i for ID so it doesn't interfere with the -s (size) short option

I'm personally not chained to any of this, so if you want the Cobra implementation but with different option names, let me know and I can change it, or you can approve and merge then change to your liking, etc.

The No Password Edge Case

When the user presents an empty key/password via the CLI (--enc ""), the user would still be prompted for password input instead of enabling no enryption protocol (NONE) which is what the user probably wants. This could probably be resolved using the old standard library but would require more than a couple lines of code. Cobra's pflag library makes this easy with the Changed method which has been implemented in this PR.

README

It has been updated with the new automatically generated Cobra help and the example command incantation updated with the new option names. For this PR, the new help output is:

$ wifiqr --help
wifiqr is a WiFi QR code generator

It is used to create a QR code containing the login details such as
the name, password, and encryption type. This QR code can be scanned
using Google Lens or other QR code reader to connect to the network.
It is Android and iOS compatible.

If the options necessary for creating the QR code are not given on
the command line, the user will be prompted for the information.

Usage:
  wifiqr [flags]

Flags:
  -h, --help              help for wifiqr
      --hidden            Hidden SSID
  -k, --key string        Wireless password (pre-shared key / PSK)
  -o, --output string     PNG file for output (default stdout)
  -p, --protocol string   Wireless network encryption protocol (WPA2, WPA, WEP, NONE). (default "WPA2")
  -s, --size int          Image width and height in pixels (default 256)
  -i, --ssid string       Wireless network name
  -v, --version           version for wifiqr

And the version output example:

$ wifiqr --version
wifiqr version 0.9.9

Why?

I'm submitting all these PRs because I use this utility every week to connect to a protected wifi network. I'm a software developer that enjoys coding in Go. Put them together and I just wanted to give back. I also have the opinion that Cobra should be used to process user input for nearly every Go application. Thanks for accepting my previous PRs.

Background information for these changes can be found on ZXing's Wi-Fi Network config documentation section which is also referenced from the Wikipedia page and section on wifi networks.

No Encryption

No WiFi encryption is now supported. This is enabled on the command line with the -enc option which can be set to NONE, NOPASS, or empty with -enc "" and the user will not be prompted for a password. In the case where an invalid protocol is specified, the selection list now includes a NONE option after which the user is not prompted for a password. As before, the encryption protocol defaults to WPA2.

Escape of SSID and Password

Special characters in the SSID and password are now escaped with backslashes (\).

Increased Unit Testing

Unit tests have been added to support some of the new functionality, for building the string used to generate the QR code (buildSchema) and a few other functions.

• Remove use of variables that aren't really needed in InitCode
• Eliminate the use of strings.Builder overhead
  • Also removes import of strings package
  • Speeds execution of buildSchema by 35%+
  • Significant decreased memory usage by buildSchema

The refinement of buildSchema is probably not really useful when used from a command line utility, but if someone was to use this package as part of a REST API or other utility that performs this work repeatedly, it helps with memory use and runtime overhead.

The output of benchcmp:

benchmark                 old ns/op     new ns/op     delta
Benchmark_buildSchema     200           125           -37.49%

benchmark                 old allocs     new allocs     delta
Benchmark_buildSchema     4              1              -75.00%

benchmark                 old bytes     new bytes     delta
Benchmark_buildSchema     120           48            -60.00%

Function used for benchmarking:

func Benchmark_buildSchema(b *testing.B) {
	cfg := Config{
		SSID:       "testssid",
		Key:        "testkeytestkey",
		Encryption: "WPA2",
		Hidden:     false,
	}

	for i := 0; i < b.N; i++ {
		buildSchema(&cfg)
	}
}

• Inject tagged version into released binary
  • No more need to modify source for each version
• Reduce size of released binaries
  • -s: Omit symbol and debug info
  • -w: Omit DWARF symbol table
• Builds for more platforms as might have been originally intended
• Git ignore files in dist/
  • Helps with testing GoReleaser locally with a command such as goreleaser --skip-publish --rm-dist

go install (https://go.dev/ref/mod#go-install) is recommended as the way to install binaries rather than go get.

If I run go get github.com/reugn/wifiqr from the README.md I see the following output:

go: go.mod file not found in current directory or any parent directory.
	'go get' is no longer supported outside a module.
	To build and install a command, use 'go install' with a version,
	like 'go install example.com/cmd@latest'
	For more information, see https://golang.org/doc/go-get-install-deprecation
	or run 'go help get' or 'go help install'.

What do you think about updating the readme to go install github.com/reugn/wifiqr/cmd/wifiqr@latest, it will install wifiqr to the go bin folder.

Note: I tried go install github.com/reugn/wifiqr@latest but get the following output:

package github.com/reugn/wifiqr is not a main package

Looking at other projects (e.g. https://github.com/knipferrc/fm) a simple main.go at the root should do the trick to make it work.