xsv

XSV

csv handling package written in go

Most of the programs related to csv generation and reading are created from code in this repository.↓

Copyright (c) 2014 Jonathan Picques https://github.com/gocarina/gocsv

※xsv does not include gocsv.

🚀Getting Started

go get github.com/shigetaichi/xsv

🔨Usage

package main

import (
	"os"
	"xsv"
)

type Client struct { // Our example struct, you can use "-" to ignore a field
	ID            string `csv:"client_id"`
	Name          string `csv:"client_name"`
	Age           string `csv:"client_age"`
	NotUsedString string `csv:"-"`
}

func main() {
	clients := []*Client{
		{ID: "12", Name: "John", Age: "21"},
		{ID: "13", Name: "Fred"},
		{ID: "14", Name: "James", Age: "32"},
		{ID: "15", Name: "Danny"},
	}

	// Create an empty clients file
	clientsFile, err := os.OpenFile("clients.csv", os.O_RDWR|os.O_CREATE|os.O_TRUNC, os.ModePerm)
	if err != nil {
		panic(err)
	}
	defer clientsFile.Close()

	// instancing xsvWrite struct
	xsvWrite := xsv.NewXsvWrite[*Client]()
	// change some preferences
	xsvWrite.OmitHeaders = true
	// set writer and write!
	err = xsvWrite.SetFileWriter(clientsFile).Write(clients)
	if err != nil {
		return
	}

	// instancing xsvRead struct
	xsvRead := xsv.NewXsvRead[*Client]()
	// change some preferences
	xsvRead.TagName = "xsv"
	// set reader and read!
	var clientOutput []*Client
	err = xsvRead.SetFileReader(clientsFile).ReadTo(&clientOutput)
	if err != nil {
		return
	}
}

🛠️Details

XsvWrite

• TagName: string
  • Key in the struct field's tag to scan
• TagSeparator: string
  • Separator string for multiple CSV tags in struct fields
• OmitHeaders: bool
  • Whether to output headers to CSV or not
• SelectedColumns: []string
  • Slice of field names (which is set in "TagName" tag) to output
• SortOrder: []uint
  • Column sort order
• HeaderModifier: map[string]string
  • Map to dynamically change headers
• OnRecord func(T) T
  • Callback function to be called on each record

XsvRead

• TagName: string
  • Key in the struct field's tag to scan
• TagSeparator: string
  • Separator string for multiple CSV tags in struct fields
• FailIfUnmatchedStructTags: bool
  • Indicates whether it is considered an error when there is an unmatched struct tag.
• FailIfDoubleHeaderNames: bool
  • Indicates whether it is considered an error when a header name is repeated in the CSV header.
• ShouldAlignDuplicateHeadersWithStructFieldOrder: bool
  • Indicates whether duplicate CSV headers should be aligned per their order in the struct definition.
• OnRecord func(T) T
  • Callback function to be called on each record
• NameNormalizer: Normalizer(func(string) string)
  • Normalizer is a function that takes and returns a string. It is applied to struct and header field values before they are compared. It can be used to alter names for comparison. For instance, you could allow case-insensitive matching or convert '-' to '_'.
• ErrorHandler: ErrorHandler(func(*csv.ParseError) bool)
  • ErrorHandler is a function that takes an error and handles it. It can be used to log errors or to panic.