關於網路那些事...

這裡記錄一些 Elasticsearch 常用的索引操作方式，方便之後查詢參考

這裡記錄一些 Elasticsearch 核心概念及機制說明：

Tmux is a terminal multiplexer that can run multiple programs in one terminal. There is powerful to manage several programs in the remote server in one terminal, and using the session to attach or detach them. A prefix is an advanced tool that supports split windows and quick short keys.

That’s getting the start for how to using tmux. Here will showing common usage about tmux.

A service provider probably has a technology-related service contract with the client to promise about the service level availability and usability.

Here we will discuss service level terminology about SLI/SLO/SLA and User-Facing:

Database slow query is a normalized case in operation situation. For example, if a new feature in production has a long data loading time, we can check this situation in the application log or database slow query.

Here, is how to set MySql slow query log.

Saltstack is an automatic configuration management tool, easy extension infrastructure, and high performance.

Using Saltstack can easy to manage large-scale servers, include dynamic connections, can be used for remote/local execution, config management, etc.

When running Xcode and iOS simulator, open VSCode does not show the iOS device but has Android emulator options.

How to show iOS simulator in VSCode?

How to solve the problem of “another exception was thrown: Unable to load asset:” in flutter?

Here is the step for flutter how to load local images:

First, for use asset image in local, image location should be add in pubsec.yaml

Dart is created by Google in 2011, and can be use for web, server, mobile, and IoT, also can be use to develop Flutter.

Here we will present a quickly short guid for let you understand what is Dart and how to use it. For more detail about Dart can reference tour of basic Dart program.

This tutorial will demonstrate how to install flutter in Mac and build the first app with Xcode.

To install flutter and develop the app, we need to check environment meet minimum requirements

• Disk space: 2.8 G
• macOS 64-bit
• Xcode

In Visual Studio Code, I’m using the Live Sass Compiler and Live Server (both plugins are developed by Ritwick Dey) for the development HTML project.

After install Live Sass compiler and Liver Server, the quickly functional button “Watch Sass” and “Go Live” will show in the VSCode bottom status list.

Here is a tutorial for download video or streaming from Azure Media Service content.

Azure Media Player provides one player to support multiple devices and formate and integration content protection.

Azure media service is provided a stream solution with Azure Media Player, Azure media service is using manifest as streaming info contains the file.

When we need to download content from Azure media, first, we need to get the manifest URL,

Cobra is a golang library for creating CLI applications and is using by Kubernetes, Hugo, and Github CLI..

Here we will show how to use cobra to build a CLI app.

In golang project, we may need to call os environment variable for security purposes in OSX or Linux.

Here will showing how to set global environment and get value in our golang project.

Introduction Gin HTML template and how integration with bootstrap

Gin is going web framework which include server-side render template, we can transfer variable into a template and render by double braces {{ … }}.

In this article, We will introduce how to use gin template, finally will include how to integrate bootstrap with gin HTML template.

Github action use SSH to access remote host and execute a script

In this article, we will use 6 steps to illustrate how to use Github action to access a remote server and execute the shell script. So that’s getting started:

step 1. Generate keygen in local machine

In your local machine, execute the following command in the terminal and generate your ssh-keygen.

ssh-keygen -f ~/.ssh/yourhost -t ed25519 -b 4096 -C "youremail@example.com"

step 2. Copy our public key to the remote server’s authorize

# goto remote server

echo "your public keygen content" >> .ssh/authorized_keys

step 3. copy our Private Key and paste it into Github Secrets.

Go to “Settings” > “Secrets”, and click “New repository secret” button.

理解 Python package & module 入門

Python 簡單易學，並且 Python 扮演了非常好的膠水的角色，將大量功能強的大模組整合在一起，讓他成為如今火熱的程式碼。

在這裡主要會說明 Package, Module 的組成。

首先聊聊 Module

在 python 來說，我們主要都會透過 module 來將建構我們的程式碼，一個 module 簡單來說，就是一個 .py 檔案。

├── mymodule.py

例如，建立一個 saymodule.py

class sayHello():
    name = ''
    message = 'hello world'
    def To(self):
        if self.name == '':

if __name__ == '__main__':
    sayhello = sayHello()
    sayhello.name = 'adam'
    sayhello.To()

接著在 main.py 導入

from saymodule import sayHello

sayhello = sayHello()
sayhello.name = 'brother'
sayhello.To()

Python, package 與 module 的關係

在前面提到，我們可以獨立建立 module 方式來引入使用，

但是，為了可以更好的將 package 區隔開，會再透過 package，將多個 module 整合成一個 package，這個打包好的 package，就可以很方便地被拿來使用，並且，package 必須包含 __init__.py，結構如下：

Amazon VPC 基礎知識介紹

AWS 會在世界許多區域建立基礎設施，每一個 Region 就可以代表一個區域(例如，東京)，在 Region 中，通常會有多個 AZ (Ability Zone)，一個 AZ 是一個邏輯資料中心，這裡面會有多個實體資料中心。

Amazon 的 VPC (Virtual Private Cloud ) 是一個虛擬的網路區域，他是私有的會與其他帳號隔離的虛擬網路，可以將 AWS 的服務資源在 Virtual networks 中運行(也可以說，每一個實例資源創建時，就必須指定 VPC 及 subnets )，這些服務之間可以透過 VPC 網路來溝通，在雲端與本地環境無縫接軌，或者在雲端建立起一套私有的網路環境架構。

在接下來會透過幾個部分來階段是的說明 VPC 概念：

Mac 安裝 Logstash 及啟用

本篇說明如何在 Mac 本地建立 Logstash 流程，其他 Linux 相關主機原則上僅差別在安裝步驟，可直接跳到功能設定參考：

Elastic Cloud - Kibana 入門介紹

Kibana 是一個資料數據展示的系統，一般會用來管理 Elasticsearch 數據分析。在這裡我們會介紹如何在 Elastic Cloud 建立集群，如何啟動 Kibana 及配置說明，以及相關功能介紹。