Xeoncross

Login / Auth System

• Consider https://github.com/peterbourgon/ctxdata for context storage/setting cookies

Protect against:

• DoS
• Lock accounts after failed attempts
• forgotten password tokens (or remeber me, CSRF, etc..) being used as logins (hash them all)
• someone faking a login attempt and that action loging out valid user sessions

Xeoncross

Setup private Go modules

You have a git repositiory on a remote server. This is probably a VPS you have online at Digital Ocean, AWS, or some other hosting company. Could also be a docker container or raspberrypi under your desk.

Regardless, you can include the repositiory in your go projects by helping git (which Go uses) to know how to access the code over SSH.

Edit your ~/.gitconfig and make sure your host is listed. Below are examples for github, bitbucket, and my own custom VPS.

Xeoncross

aws dynamodb create-table --region <REGION> --profile <PROFILE> --table-name "<TABLE>" --attribute-definitions "AttributeName=key,AttributeType=S" --key-schema "AttributeName=key,KeyType=HASH" --billing-mode "PAY_PER_REQUEST"
aws dynamodb create-table --region <REGION> --profile <PROFILE> --table-name "<TABLE>" --attribute-definitions "AttributeName=key,AttributeType=S" --key-schema "AttributeName=key,KeyType=HASH" --billing-mode "PROVISIONED" --provisioned-throughput "ReadCapacityUnits=1,WriteCapacityUnits=1"
aws dynamodb update-time-to-live --region <REGION> --profile <PROFILE> --table-name "<TABLE>" --time-to-live-specification "Enabled=true,AttributeName=ttl"
aws dynamodb scan --region <REGION> --profile <PROFILE> --table-name "<TABLE>"

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-- See more at https://stackoverflow.com/a/49446214/99923
INSERT INTO T1 (id, created_on, domain, seen_on)
SELECT one.X, two.X, three.X, two.X
FROM (select seq, seq X from seq_1_to_100000) one 
LEFT JOIN (select seq, NOW() - INTERVAL seq MINUTE X from seq_1_to_100000) two ON one.seq = two.seq
LEFT JOIN (select seq, CONCAT(seq,'.',seq) X from seq_1_to_100000) three ON one.seq = three.seq;

Xeoncross

package bytewriter

import (
	"bytes"
	"encoding/binary"
	"testing"
)

func BenchmarkBinary(b *testing.B) {

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Lexer / Parser in Go

In Go, one of the cleanest examples of parsing text is the lexer design used in text/template. You can find the current source here.

https://github.com/golang/go/blob/c007ce824d/src/text/template/parse/lex.go

You can find the explination here:

Video: Lexical Scanning in Go - Rob Pike https://www.youtube.com/watch?v=HxaD_trXwRE

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package syncmaptest

import (
	"fmt"
	"sync"
	"testing"
	"time"
)

var lockMap = &sync.Map{}

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package main

import (
	"log"
	"net/http"

	"github.com/spf13/afero"
)

func main() {

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package main

import (
	"crypto/tls"
	"crypto/x509"
	"io/ioutil"
	"log"
	"net/http"
	"net/textproto"
	"net/url"

Xeoncross

# Assuming you are logged in as root and the ssh key you want to use already installed for root (i.e. new Digital Ocean VPS)


adduser deploy
usermod -aG sudo deploy
mkdir /home/deploy/.ssh
cp /root/.ssh/authorized_keys /home/deploy/.ssh/
chmod 700 /home/deploy/.ssh
chown deploy:deploy -R /home/deploy/.ssh