MY GO EXAMPLES

A place to keep my go examples.

Table of Contents

• ARCHITECTURES
  • BLOCKCHAIN
  • WEB SCRAPING
• CGO
  • C CODE
• CLIENT/SERVER
  • gRPC
  • HTTP
  • TCP/IP
• CLOUD SERVICE PROVIDERS
  • AMAZON WEB SERVICES
  • GOOGLE CLOUD PLATFORM
  • MICROSOFT AZURE
• CRYPTOGRAPHY
  • ASYMMETRIC CRYPTOGRAPHY
  • HASHING
  • SYMMETRIC CRYPTOGRAPHY
• DATA STRUCTURES AND ALGORITHMS
  • DATA STRUCTURES
  • ALGORITHMS
• DATABASES
  • NON-RELATIONAL
  • RELATIONAL
• ERROR HANDLING
  • BASIC
  • WRAPPING
  • SENTINELS
• FUNCTIONS, METHODS AND INTERFACES
  • FUNCTIONS
  • METHODS
  • INTERFACES
• GO RUNTIME
  • GOROUTINES
  • INTERACT GO RUNTIME
  • INTERACT HOST OS
• INPUT/OUTPUT
  • IO READER
  • IO WRITER
• IN-PROCESS COMMUNICATION
  • SHARED MEMORY
  • MESSAGE PASSING
• INTER-PROCESS COMMUNICATION (IPC)
  • SHARED MEMORY
  • MESSAGE PASSING
• IoT
  • RASPBERRY PI
• MODULES AND PACKAGES
  • LOCAL PACKAGES
  • REMOTE PACKAGES
• MY GENERIC GO TEMPLATES
  • JEFFS BASIC TEMPLATE
• PROGRAM BASICS
  • FLAGS
  • LOGGING
• STRUCTS AND TYPES
  • STRUCTS
  • CONSTRUCTORS
  • GENERICS
• TESTING
  • UNIT TESTS
  • TABLE-DRIVEN TESTS
  • BENCHMARKS
  • FUZZING

Appendix

• STANDARD GO PACKAGES

Documentation and Reference

• go
• go standard library
• my-go-packages
• my-go-tools
• This repos github webpage built with concourse

ARCHITECTURES

• BLOCKCHAIN

  • bitcoin-ledger - Demonstrates a bitcoin ledger in a blockchain using the unspent transaction output model.
  • create-bitcoin-address-from-ecdsa-publickey - Create a bitcoin address from your ecdsa public key using the crypto/ecdsa standard package.
  • single-node-blockchain-with-REST - A simple single node sha256 blockchain with a REST JSON API (to view (GET) the blockchain and add (POST) a block).

• WEB SCRAPING

  • [web scrape twitter for ???]

CGO

• C CODE

  • simple-c-code - A very simple example to show you how to write a c function in go.
  • simple-c-code-using-stdio - A c function in go using stdio.h for printf.

CLIENT/SERVER

• gRPC

  • - Coming soon.

• HTTP

  • - Coming soon.

• TCP/IP

  • - Coming soon.

CLOUD SERVICE PROVIDERS

• AMAZON WEB SERVICES

  • - Coming soon.

• GOOGLE CLOUD PLATFORM

  • - Coming soon.

• MICROSOFT AZURE

  • - Coming soon.

CRYPTOGRAPHY

• ASYMMETRIC CRYPTOGRAPHY (Great for digital signatures (verify sender) and receiving encrypted data)

  • - Coming soon.

• HASHING (Great for getting fingerprints)

  • - Coming soon.

• SYMMETRIC CRYPTOGRAPHY (Using the same key to encrypt and decrypt)

  • - Coming soon.

DATA STRUCTURES AND ALGORITHMS

• DATA STRUCTURES

  • BUILT-IN

    • arrays - A fixed-length collection of elements of the same type.
    • slices - A flexible dynamically-sized array.
    • maps - An unordered collection of key-value pairs (a hash table).

  • FROM SCRATCH

    • sets - A collection of unique elements built from a map.
    • stack - A LIFO (last-in first-out) built from a slice.
    • queue - A FIFO (first-in first-out) built from a slice.
    • linked-list - A linked-list built from a struct with a pointer to the next node.
    • binary-tree - A tree built from a struct with pointers to left/right children.

• ALGORITHMS

  • SEARCHING

    • linear-search - Find a value by scanning each element in turn (O(n)).
    • binary-search - Find a value in a sorted slice by repeatedly halving the range (O(log n)).

  • SORTING

    • bubble-sort - Sort by repeatedly swapping adjacent out-of-order pairs (O(n²)).
    • quick-sort - Sort by partitioning around a pivot and recursing (O(n log n) average).

DATABASES

• NON-RELATIONAL

  • - Coming soon.

• RELATIONAL

  • - Coming soon.

ERROR HANDLING

• BASIC

  • error-simple - Error handling using the errors standard package.

• WRAPPING

  • error-wrapping - Wrapping errors with %w to add context as they propagate up the call stack using the errors standard package.

• SENTINELS

  • error-sentinel - A sentinel is a named error that callers can check for by identity using the errors standard package.

FUNCTIONS, METHODS AND INTERFACES

• FUNCTIONS

  • functions - Using functions to calculate the area of a rectangle and circle.
  • functions-pointers-arguments - Using functions to resize a rectangle and circle by passing pointers.

• METHODS

  • methods - Using methods to calculate the area of a rectangle and circle.
  • methods-pointers-receivers - Using methods to resize a rectangle and circle using pointer receivers.

• INTERFACES

  • interfaces - Using an interface to calculate the area of a rectangle and circle.
  • interfaces-pointers-receivers - Using an interface to resize a rectangle and circle using pointer receivers.

GO RUNTIME

• GOROUTINES

  • goroutines-multi-core - Concurrency across multiples cores. You can play around with workers, threads, cpus/cores and nice to find the fastest performance. It will find the total number of prime numbers within a range. Lightweight goroutines are amazing.
  • goroutines-waitgroup - Concurrency using a waitgroup (waiting for a collection of goroutines to finish).
  • goroutines-worker-pools - Concurrency using worker pools.

• INTERACT GO RUNTIME

  • simple-go-runtime-interactions - A few go runtime interactions using the runtime standard package.

• INTERACT HOST OS

  • simple-external-commands - Run a few os commands using the os/exec standard package.
  • simple-os-interactions - A few os interactions using the syscall package.

INPUT/OUTPUT

• IO READER

  • io-reader - Read data (a stream of bytes) from a string, buffer, file, stdin and a pipe to a buffer using the io standard package.
  • io-reader-simple - Read data (a stream of bytes) from a buffer to a buffer using the io standard package.
  • read-file - Read a file (*os.File) to a buffer.
  • read-user-input - Read user input (os.Stdin) to a buffer (using Read method) and string (using Fscan).

• IO WRITER

  • io-writer - Write data (a stream of bytes) to a buffer, file, stdout and a pipe from a buffer using the io standard package.
  • io-writer-simple - Write data (a stream of bytes) to a buffer from a buffer using the io standard package.

IN-PROCESS COMMUNICATION

• SHARED MEMORY

  • ASYNCHRONOUS

    • - Coming soon.

  • SYNCHRONOUS

    • pipes-unnamed-simple - A pipe provides a uni-directional communication channel. This is a very simple example of an unnamed pipe.
    • pipes-unnamed - This is a more robust example of an unnamed pipe showing multiple reads.
    • pipes-unnamed-io - This example of an unnamed pipe connects an io.Writer and io.Reader.

• MESSAGE PASSING

  • ASYNCHRONOUS

    • channels-buffered - Buffered channels are uni-directional, asynchronous with no blocking.

  • SYNCHRONOUS

    • channels-unbuffered - Unbuffered channels are uni-directional, synchronous with blocking.

INTER-PROCESS COMMUNICATION (IPC)

• SHARED MEMORY

  • ASYNCHRONOUS

    • - Coming soon.

  • SYNCHRONOUS

    • pipes-named - Sending data over a named-pipe (FIFO) from one process to another process.

• MESSAGE PASSING

  • OPERATING SYSTEM

    • ASYNCHRONOUS

      • message-queues - Coming soon.
      • pub-sub-nats-os - Coming soon.
      • tcp - Coming soon.

    • SYNCHRONOUS

      • grpc-os - Start a grpc server in the go runtime environment using googles grpc package.

  • NETWORK

    • ASYNCHRONOUS

      • pub-sub-nats-network - Coming soon.
      • tcp-ip - Coming soon.

    • SYNCHRONOUS

      • grpc-network - Start a grpc server in the go runtime environment using googles grpc package.
      • rest - Coming soon.

IoT

• RASPBERRY PI

  • blink-led-raspberry-pi-gpio-periph - GPIO OUTPUT - Blink an LED via a Raspberry Pi GPIO using the periph.io/... packages.
  • push-button-raspberry-pi-gpio-periph - GPIO INPUT - Push a button via a Raspberry Pi GPIO using the periph.io/... packages.
  • toggle-led-with-button-raspberry-pi-gpio-periph - Toggle an LED with a button push via a Raspberry Pi GPIO using the periph.io/... packages.

MODULES AND PACKAGES

• LOCAL PACKAGES

  • module-with-local-package - A go module with a local package.

• REMOTE PACKAGES

  • module-with-remote-package - A go module with a remote (public) package.

MY GENERIC GO TEMPLATES

• JEFFS BASIC TEMPLATE

  • jeffs-basic-go-template - My generic go template with flags, logging & error handling. A place to see how everything fits together.

PROGRAM BASICS

• FLAGS

  • flags - The flag standard package makes it easy to implement command-line flag parsing.

• LOGGING

  • jeffs-logger - Logging using my github.com/JeffDeCola/my-go-packages/golang/logger which uses the structured logging log/slog standard package.

STRUCTS AND TYPES

• STRUCTS

  • structs-basic - Declaring a struct, creating instances and accessing fields.
  • structs-nesting-embedding - Nesting and embedding a struct inside another struct, and how field access differs between them.

• CONSTRUCTORS

  • constructor-simple - Constructors are functions that build and return a new instance of a struct, often with defaults.
  • constructor-with-error - Expanding on constructor-simple to add a configuration struct and error handling.

• GENERICS

  • generics-function - A generic function uses a type parameter so a and b are the same type, and so is the result - one function for many types instead of copy-pasting.
  • generics-type - A generic type uses a type parameter so one definition serves every element type, instead of writing one type per element.

TESTING

• UNIT TESTS

  • - Coming soon.

• TABLE-DRIVEN TESTS

  • - Coming soon.

• BENCHMARKS

  • - Coming soon.

• FUZZING

  • - Coming soon.

STANDARD GO PACKAGES

Current as of go 1.26.4.

• archive
  • tar
  • zip
• bufio
• builtin (documentation-only - where len, make, panic, etc. live)
• bytes
• cmp
• compress
  • bzip2
  • flate
  • gzip
  • lzw
  • zlib
• container
  • heap
  • list
  • ring
• context
• crypto
  • aes - encryptfile tool, decryptfile tool
  • ecdsa - create-bitcoin-address-from-ecdsa-publickey
  • elliptic - create-bitcoin-address-from-ecdsa-publickey
  • hpke
  • md5 - md5-hash-file tool
  • rand - create-bitcoin-address-from-ecdsa-publickey
  • sha256 - create-bitcoin-address-from-ecdsa-publickey, sha256-hash-file tool
  • x509 - create-bitcoin-address-from-ecdsa-publickey
  • etc...
• database
  • sql
  • sql-driver
• debug
  • buildinfo
  • dwarf
  • etc...
• embed
• encoding
  • hex - create-bitcoin-address-from-ecdsa-publickey
  • pem - create-bitcoin-address-from-ecdsa-publickey
  • etc...
• errors - error-simple, error-wrapping, error-sentinel
• expvar
• flag - flags
• fmt
• go
  • ast
  • build
  • etc...
• hash
  • adler32
  • crc32
  • crc64
  • fnv
  • maphash
• html
  • template
• image
  • color
  • color/palette
  • draw
  • gif
  • jpeg
  • png
• index
  • suffixarray
• io - io-reader, io-reader-simple, io-writer, io-writer-simple
  • fs
  • ioutil
• iter
• log
  • slog - jeffs-logger
  • syslog
• maps
• math
  • big
  • bits
  • cmplx
  • rand
  • rand/v2
• mime
  • multipart
  • quotedprintable
• net
  • http
  • http/cgi
  • etc...
• os
  • exec - simple-external-commands
  • signal
  • user
• path
  • filepath
• plugin
• reflect - create-bitcoin-address-from-ecdsa-publickey
• regexp (syntax)
• runtime - simple-go-runtime-interactions
  • cgo
  • coverage
  • etc...
• slices
• sort
• strconv
• strings
• structs
• sync (atomic)
• syscall - simple-os-interactions
  • js
• testing
  • cryptotest
  • fstest
  • iotest
  • quick
  • slogtest
  • synctest
• text
  • scanner
  • tabwriter
  • template
  • template/parse
• time
  • tzdata
• unicode
  • utf16
  • utf8
• unique
• unsafe
• weak