Go utils

Helper package for our go projects.

Slice

StringInSlice()

JSON

RenderDataAsJSON()

WriteJson()

Request

ParseFromRequest()

ReadAndRewind()

GetMatchingPrefixLength()

SendRequest()

This function will try to send the request in the background several times if the response is failes.

Example usage:

type MyType struc {
  Field1 string `json:"field1"`
  Field2 string `json:"field2"`
}
myValue := MyType{
  Field1: "Hello",
  Field2: "GO",
}
queryBody, _ := json.Marshal(myValue)
contentReader := bytes.NewBuffer(queryBody)
  go func() {
    cancel := make(chan bool)
    res := utils.SendRequest(utils.Request{
      URL:     "http://example.com",
      Method:  "POST",
      Body:    contentReader,
      Headers: []http.Header{{"Content-Type": []string{"application/json"}}},
    })

    response := <-res
    if response == nil {
      log.Println("request failed")
    } else {
      log.Printf("cool, the reponse is: %v\n", response)
    }
  }()

If you want to cancel the request just set it in the cancel chanel:

go func() {
    cancel := make(chan bool)
    res := utils.SendRequest(utils.Request{
      URL:     "http://example.com",
      Method:  "POST",
      Body:    contentReader,
      Headers: []http.Header{{"Content-Type": []string{"application/json"}}},
      Cancel:  cancel,
    })
    time.Sleep(time.Second * 5)
    cancel <- true
  }()

Or if you want to combine them:

go func() {
    cancel := make(chan bool)
    res := utils.SendRequest(utils.Request{
      URL:     "http://example.com",
      Method:  "POST",
      Body:    contentReader,
      Headers: []http.Header{{"Content-Type": []string{"application/json"}}},
      Cancel:  cancel,
    })
    go func() {
      time.Sleep(time.Second * 5)
      cancel <- true
    }()
    response := <-res
    if response == nil {
      log.Println("this request is failed")
    } else {
      log.Printf("cool, the reponse is: %v\n", response)
    }
  }()

Misc

RandomHash()

Error

Not Found Error Handling

This package provides tools for consistent handling of "not found" errors. These tools allow services to uniformly address cases when a resource cannot be found.

ErrNotFound

A generic error representing a "resource not found" case:

var ErrNotFound = errors.New("resource not found")

RegisterNotFoundError()

Allows services to register custom "not found" errors specific to their domain (e.g., a database error such as MongoDB's mongo.ErrNoDocuments).

Example 1:

import (
	"errors"
	"go.mongodb.org/mongo-driver/mongo"
)

// Register the MongoDB "not found" error.
utils.RegisterNotFoundError(mongo.ErrNoDocuments)

// Usage example:
err := mongo.ErrNoDocuments
if utils.IsNotFoundError(err) {
	fmt.Println("This is a 'not found' error")
}

Example 2:

dbError := errors.New("database entry not found")
utils.RegisterNotFoundError(dbError)

IsNotFoundError()

Checks whether the given error matches ErrNotFound or any of the registered custom "not found" errors.

Example:

err := errors.New("database entry not found")
if utils.IsNotFoundError(err) {
    fmt.Println("This is a 'not found' error")
}

Other errors

ErrInvalidUrl

ErrInvalidMail

ErrInvalidMongoIdHash

Types

Url

• String()
• Validate()

Email

• String()
• Validate()