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  errGroup in GoLang explained

Today, let's talk about the usage and applicable scenarios of errGroup, which is often used. Why is it useful? Generally, when we use goroutine, we cannot return a value. If you want to pass out the result of the goroutine execution, you usually have to use the channel. The errGroup package is suitable if you want to know when the goroutine you opened encounters an error during execution and stop working, and I need to know the error value. errGroup usage The package needs to be downloaded and i...

   GOLANG,ERRGROUP,WAITHROUP,CONCURRENCY     2023-05-27 23:58:20

  Create temp file in Bash using mktemp and trap

When working on Linux Bash, sometimes there is need to create temporary file. A common way of creating temp file on Linux is creating some file in /tmp directory. However there is security risk when creating temp file in /tmp directory. This post will show how to securely create temp file in Linux Bash. When creating file in /tmp directory, there are some security risks. This directory can be accessed by any user on the system, any user can write data into this directory as well. The files creat...

   LINUX,MKTEMP,TRAP,TEMP FILE     2019-12-30 23:28:23

  Be careful about printing error as string in GoLang

In GoLang, we can format and produce string using fmt.Printf(), just like C, GoLang also supports format verbs like %s, %d which can be placeholder for different types of values. But please pay attention when printing error as string so that you will not fall into some trap. Let's first take an example code snippet and see what trap we are talking about. package main import "fmt" type A string func (a A) Error() string { return fmt.Sprintf("%s is an error", a) } func main() { a := A("hello...

   STACKOVERFLOW,GOLANG,FMT     2019-01-23 09:17:15

  Some frequently used ES6 code snippets

Below are a list of ES6 code snippets which are used frequently. Hope that it will be helpful. 1. Shuffle array elements let arr = [67, true, false, '55'] arr = arr.sort(() => 0.5 - Math.random()) console.log(arr) // [ '55', 67, false, true ] 2. Remove characters which are not numbers const str = 'xieyezi 23213 is 95994 so hansome 223333' const numbers = str.replace(/\D/g, '') console.log(numbers) // 2321395994223333 3. Reverse sequence or words const sentence = 'xieyezi js so handsome, lol.'...

   JAVASCRIPT,ES6,CODE SNIPPET,TIPS     2022-04-10 07:56:07

  OpenLDAP Proxy -- Tricks and tips

Just like other software configuration, there would be issues encountered during the OpenLDAP proxy setup process. In this post, we would try to summarize some of the tricks and tips for OpenLDAP proxy setup. OpenLDAP Version We would always recommend that you install the latest version of the OpenLDAP because they contain the latest features, bug fixes and security patches. You should always refer to the latest release notes for new changes. In case you have used an earlier version of Open...

   SSL,AUTHENTICATION,OPENLDAP,OPENLDAP PROXY,ATTRIBUTE MAPPING,OVERLAY     2017-11-04 04:29:38

  Gemini Example with Go

To connect and use Gemini with Go, Google's LLM, one can use their official Go SDK for doing this. In this post, we will just show a simple chat example to demonstrate how to make it work with Go. The example is just to ask the model to translate some English to Chinese and get its output. The code actually looks like: var client *genai.Client // geminiOnce.Do(func() { client, err = genai.NewClient(ctx, option.WithAPIKey(string(apiKey))) if err != nil { log.Fatal(err) } model := client.Genera...

   EXAMPLE,GO,TRANSLATION,GOLANG,GEMINI     2024-12-14 19:37:23

  Fastjson just fixed a bug which might cause out of memory issue

Fastjson just fixed a bug which might cause service down a few days ago. This bug is caused by some mishandling of special character \x which is an escaped character to indicate hexdecimal number. The impact of this bug would be big if the attacker constructs a malicious data which would cause the service down.  The code which causes the issue is in com.alibaba.fastjson.parser.JSONLexerBase#scanString, when a JSON string is passed in, fastjson would parse the string character by c...

   FASTJSON,ALIBABA,BUG,NEWS     2019-09-07 06:03:49

  Why no max/min function for integer in GoLang

You may notice that there is no max/min function provided to compare the maximum/minimum of two or more integers if you are a GoLang developer with some experience . In other languages, these functions are provided as part of the core lib functions. Have you wondered why?  Indeed GoLang provides max/min function in math package, but they are used for comparing float64 data type. The signature of these two functions are math.Min(float64, float64) float64 math.Max(float64, float64) float...

   GOLANG,MAX,INT,INT64     2019-06-08 07:00:55

  Install PHP 8 in WampServer

With the release of PHP 8.4, there are some new features added in, it reminds me that I may need to upgrade my development environment PHP version as well. It has php 5.x and php 7.x installed already, now I need to add php 8.x as well. This post will show the steps to achieve this. Step 1 Install PHP 8.x The first step is that we need to download the new PHP version. Here we chose PHP 8.1.31. Once the zip file is downloaded, unzip it and copy the folder to c:/wamp64/bin/php and rename the folde...

   WAMP,GUIDE,PHP VERSION,PHP 8     2024-11-24 02:43:22

  Cool things you can do with iPhone

Nowadays smart phones have plenty of cool features you can get to know without reading the manuals. But do you know there are some useful but less well known features which can ease our life? In this post, we will share with you some cool features on iPhone. If you have an iPhone with, go and get a try. 1. Use Google Map as free GPS While traveling abroad, you can use Google Maps as a free GPS without an international data plan by making use of it's hidden offline maps feature.You can use this f...

   iPhone,Feature     2013-10-05 07:28:07

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