A place to share what I learn/experience

"Life is all about sharing. If we are good at something, pass it on." - Mary Berry

gocloud - writing data to a bucket: 403

2022-12-23

Problem

We are writing some integration test using Go CDK. After writing some data to a bucket:

1	writer, err := buckOut.NewWriter(ctx, fileDst, nil)
2	if err != nil {
3		logger.Errorf("failed to write to fileDst: %v", err)
4		return err
5	}
6	defer writer.Close()

we got an error when reading:

1(code=NotFound): storage: object doesn't exist

By reading the documentation, I pay attention to this:

Closing the writer commits the write to the provider, flushing any buffers, and releases any resources used while writing, so you must always check the error of Close.

Terraform failed to acquire state lock: 403: Access denied., forbidden

2022-11-17

Problem

We stored Terraform state in gcs. For some reasons, we got this error randomly when running on BitBucket pipelines:

 1╷
 2│ Error: Error acquiring the state lock
 3│ 
 4│ Error message: 2 errors occurred:
 5│ 	* writing
 6│ "gs://bucket/path/to/default.tflock"
 7│ failed: googleapi: Error 403: Access denied., forbidden
 8│ 	* storage: object doesn't exist
 9│ 
10│ 
11│ 
12│ Terraform acquires a state lock to protect the state from being written
13│ by multiple users at the same time. Please resolve the issue above and try
14│ again. For most commands, you can disable locking with the "-lock=false"
15│ flag, but this is not recommended.
16╵

The King of Vietnamese language game show

2022-11-04

My family likes to watch “The King of Vietnamese language” game show together. I want to encourage our son to love Vietnamese. At the end of the game, the player has to find 7 complex words from the letters, for e.g,

đ / ă / n / g / c / a / y

One evening a few weeks ago, while we were watching the final round, my wife suddenly came up with an idea: this game could be programmed.

How to run a pipeline step only when pushing to a new branch?

2021-01-07

GitHub sends push hook when pushing to a new branch and merging a PR. How can we distinguish between them?

We are running integration test by triggering a downstream build when a PR is merged into specific branches. In the downstream repository, we pull all the docker images which has been built and pushed from upstream. The thing is we also used the drone-convert-pathschanged to only publish what modules has been changed.

So, what happens when pushing to a new release-* branch?

How to add full text search to my static website?

2020-12-30

After building the website, I want to add search function. There are some ways to do it:

ElasticSearch: setup and maintenance cost
MongoDB: have to insert posts into database
Google Custom Search Engine: ads?

So, is there any search engine written in Go?

Bleve
riot

Bleve has more star and be maintained more often than riot, I would like to give it a try first.

Backend

Looking at the documentation, there are three steps to add search to your website:

How to perform integration testing in Go?

2020-09-29

Integration testing can be triggered by using Drone downstream plugin:

 1steps:
 2- name: trigger
 3  image: plugins/downstream:linux-amd64
 4  settings:
 5    params:
 6    - COMMIT_BRANCH=${DRONE_COMMIT_BRANCH}
 7    repositories:
 8    - repo/integration-test@${DRONE_COMMIT_BRANCH}
 9    server: https://drone.example.com
10    token:
11      from_secret: drone_token

It can be separated with unit tests by using build tags:

1// +build integration
2
3package webserver_test

Then we can write code to perform integration test as usual.

Save draft mail in Zimbra web client using ChromeDP

2020-07-03

As an engineer, I want to automate everything as much as possible. This CLI tool is created to save a draft mail in Zimbra web client.

Read config file:

 1func initConfig() {
 2	if cfgFile != "" {
 3		// Use config file from the flag.
 4		viper.SetConfigFile(cfgFile)
 5	} else {
 6		// Find home directory.
 7		home, err := homedir.Dir()
 8		if err != nil {
 9			fmt.Println(err)
10			os.Exit(1)
11		}
12
13		// Search config in home directory with name ".zwc" (without extension).
14		viper.AddConfigPath(home)
15		viper.SetConfigName(".zwc")
16	}
17
18	viper.AutomaticEnv() // read in environment variables that match
19
20	// If a config file is found, read it in.
21	if err := viper.ReadInConfig(); err != nil {
22		log.Fatal(err)
23	}
24
25	fmt.Println("Using config file:", viper.ConfigFileUsed())
26}

Google Calendar CLI

2020-04-13

Our company allows us to work from home some days a week. To do that, we have to create an event in Google Calendar.

I created this tool to run it from CLI.

First, take a look at this quickstart.

Create initical code by running:

1$ cobra init
2
3$ tree -L 2
4.
5├── LICENSE
6├── cmd
7│   └── root.go
8├── main.go

Create event command:

 1$ cobra add event
 2$ cobra add insert -p 'eventCmd'
 3
 4$ tree -L 2
 5.
 6├── LICENSE
 7├── cmd
 8│   ├── event.go
 9│   ├── event_insert.go
10│   └── root.go
11├── main.go

database/sql: never ignore errors

2019-10-16

I’m reading Building RESTful Web Services with Go. And in chapter 4, there is an example to play around with SQLite:

 1db, err := sql.Open("sqlite3", "./books.db")
 2if err != nil {
 3	log.Fatal(err)
 4}
 5
 6statement, err := db.Prepare("CREATE TABLE IF NOT EXISTS books (id INTERGER PRIMARY KEY, isbn INTEGER, author VARCHAR(64), name VARCHAR(64) NULL)")
 7if err != nil {
 8	log.Fatal(err)
 9} else {
10	log.Println("Created table books successfully")
11}
12statement.Exec()
13
14statement, err = db.Prepare("INSERT INTO books (name, author, isbn) VALUES (?, ?, ?)")
15if err != nil {
16	log.Fatal(err)
17}
18statement.Exec("Life is a joke", "The Javna brothers", 123456789)
19log.Println("Inserted first book into db")
20rows, err := db.Query("SELECT id, name, author FROM books")
21var tempBook Book
22for rows.Next() {
23	rows.Scan(&tempBook.id, &tempBook.name, &tempBook.author)
24	log.Printf("ID: %d, Book: %s, Author: %s\n", tempBook.id, tempBook.name, tempBook.author)
25}

How do I build this blog?

2019-10-11

Raspberry Pi 4

Recently, I decided to find a new job as a Golang developer. So, I updated my resume, sent to my friends to ask for review. Then I submitted it enclosed herewith a cover letter to recruiters. Some didn’t reply, and the other replied with a message like this “You are so good, but I’m so sorry…”.

What is the reason?

As you can see in my resume, I started my career as a .NET developer, then my passionate on Linux and open source lead me to a different direction: system administrator. And I followed this nearly in 9 years before switching back to work as a Golang developer 2 years ago.