yerstd

Nix on macOS Catalina

I'm writing this gist for my own records but it might help someone else too.

Installing Nix

Support for Catalina has improved a lot since the update was first rolled out.

Note: See the NixOS manual for discussion of the --darwin-use-unencrypted-nix-store-volume option.

Getting github access on a firewalled system

This approach, based on [0] and [1] lets me reverse-tunnel through the local machine, to get github (and other) access on protected machines, such as HPC compute systems.

I put these lines in my local ~/.ssh/config file

Host somehpcsocks
 ProxyCommand ssh -D 2020 localhost nc -q 1 localhost 22

example: https://medium.com/swlh/build-and-use-go-packages-as-c-libraries-889eb0c19838

https://medium.com/@walkert/fun-building-shared-libraries-in-go-639500a6a669

https://www.darkcoding.net/software/building-shared-libraries-in-go-part-2/

https://karthikkaranth.me/blog/calling-c-code-from-go/

MOVE TO HERE

注意以下命令，需要切换到 root 后运行

安装 docker

首先确定已经安装完成 docker，如果没有安装可以使用以下脚本快速安装并配置：

移动端H5图片压缩上传

大体的思路是，部分API的兼容性请参照caniuse：

利用FileReader,读取blob对象,或者是file对象，将图片转化为data uri的形式。
使用canvas,在页面上新建一个画布,利用canvas提供的API,将图片画入这个画布当中。
利用canvas.toDataURL()，进行图片的压缩，得到图片的data uri的值
上传文件。

步骤1当中，在进行图片压缩前，还是对图片大小做了判断的，如果图片大小大于200KB时，是直接进行图片上传，不进行图片的压缩，如果图片的大小是大于200KB，则是先进行图片的压缩再上传:

	use std::str;

	fn main() {
	// -- FROM: vec of chars --
	let src1: Vec<char> = vec!['j','{','"','i','m','m','y','"','}'];
	// to String
	let string1: String = src1.iter().collect::<String>();
	// to str
	let str1: &str = &src1.iter().collect::<String>();
	// to vec of byte

	#include <iostream>
	#include <stdio.h>
	#include <string.h>
	#include <openssl/rsa.h>
	#include <openssl/pem.h>
	#include <openssl/err.h>

	#define CRYPTO_RSA_KEY_LEN_4096 4096
	#define CRYPTO_RSA_KEY_LEN_2048 2048
	#define CRYPTO_RSA_KEY_LEN_1024 1024

	version: '2.2'
	services:
	elasticsearch:
	image: docker.elastic.co/elasticsearch/elasticsearch:6.4.1
	container_name: elasticsearch
	environment:
	- cluster.name=docker-cluster
	- bootstrap.memory_lock=true
	- "ES_JAVA_OPTS=-Xms512m -Xmx512m"
	ulimits:

	func TestRedis(t *testing.T) {
	s, _ := testutil.PrepareTestRedis()
	for i := 0; i < 10000; i++ {
	s.Set("key"+strconv.Itoa(i), "hoge"+strconv.Itoa(i))
	}
	client := redis.NewClient(&redis.Options{Addr: s.Addr()})

	// 普通にループ
	result := map[string]string{}
	for i := 0; i < 10000; i++ {

	version: "3"

	services:
	sonarqube:
	image: sonarqube
	expose:
	- 9000
	ports:
	- "127.0.0.1:9000:9000"
	networks: