csvutil

README

csvutil

Installation

go get -u github.com/sj14/csvutil

Examples

For all options please check the godoc. The examples ignore all error handling!

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Create a new dataset

All datasets should contain a header for further processing.

records := [][]string{
    {"first_name", "last_name", "username"},
    {"Rob", "Pike", "rob"},
    {"Ken", "Thompson", "ken"},
    {"Robert", "Griesemer", "gri"},
}

ds := csvutil.New(records)

Add a new row

ds.AddRow([]string{"my first name", "my last name", "my nick"})

first_name,last_name,username
Rob,Pike,rob
Ken,Thompson,ken
Robert,Griesemer,gri
my first name,my last name,my nick

Add multiple rows

ds.AddRows([][]string{
    {"my first name 0", "my last name 0", "my nick 0"},
    {"my first name 1", "my last name 1", "my nick 1"},
    {"my first name 2", "my last name 2", "my nick 2"},
})

first_name,last_name,username
Rob,Pike,rob
Ken,Thompson,ken
Robert,Griesemer,gri
my first name 0,my last name 0,my nick 0
my first name 1,my last name 1,my nick 1
my first name 2,my last name 2,my nick 2

Add a new column at index 1

ds.AddCol([]string{"column_headline", "my row 1", "my row 2", "my row 3"}, 1)
ds.Write(os.Stdout)

first_name,column_headline,last_name,username
Rob,my row 1,Pike,rob
Ken,my row 2,Thompson,ken
Robert,my row 3,Griesemer,gri

Get Column

lastNames, _ := ds.GetCol("last_name")
fmt.Println(lastNames)

[last_name Pike Thompson Griesemer]

Rename Column

ds.RenameCol("username", "nick")

first_name,last_name,nick
Rob,Pike,rob
Ken,Thompson,ken
Robert,Griesemer,gri

Move Column

ds.MoveCol("first_name", 1)

last_name,first_name,nick
Pike,Rob,rob
Thompson,Ken,ken
Griesemer,Robert,gri

Delete Column

ds.DeleteCol("first_name")

last_name,nick
Pike,rob
Thompson,ken
Griesemer,gri

Modify Column

addRowNumber := func(val string, i int) string { return fmt.Sprintf("%v (%v)", val, i) }
ds.ModifyCol("first_name", addRowNumber)
ds.Write(os.Stdout)

first_name,last_name,username
Rob (1),Pike,rob
Ken (2),Thompson,ken
Robert (3),Griesemer,gri

Write the dataset

ds.Write(os.Stdout)

first_name,last_name,username
Rob,Pike,rob
Ken,Thompson,ken
Robert,Griesemer,gri

Write options

ds.Write(os.Stdout, csvutil.Delimiter('|'), csvutil.UseCLRF(true))

first_name|last_name|username
Rob|Pike|rob
Ken|Thompson|ken
Robert|Griesemer|gri

Get dataset as [][]string

fmt.Println(ds.Raw())

[[first_name last_name username] [Rob Pike rob] [Ken Thompson ken] [Robert Griesemer gri]]

Compare two (raw) datasets

a := [][]string{
    {"a", "b", "c"},
    {"d", "e", "f"},
}

b := [][]string{
    {"g", "h", "i"},
    {"j", "k", "l"},
}

result := csvutil.Equals(a, b)
fmt.Println(result)

false

Documentation

Index

• Variables
• func Delimiter(delimiter rune) option
• func Equals(datasetA, datasetB [][]string) bool
• func UseCLRF(useCLRF bool) option
• type Dataset
  • func New(dataset [][]string) Dataset
  • func (ds *Dataset) AddCol(column []string, index int) error
  • func (ds *Dataset) AddRow(row []string) error
  • func (ds *Dataset) AddRows(rows [][]string) error
  • func (ds *Dataset) DeleteCol(name string) error
  • func (ds *Dataset) GetCol(name string) ([]string, error)
  • func (ds *Dataset) ModifyCol(name string, f func(val string, row int) string) error
  • func (ds *Dataset) MoveCol(name string, index int) error
  • func (ds *Dataset) Raw() [][]string
  • func (ds *Dataset) RenameCol(old, new string) error
  • func (ds *Dataset) Write(writer io.Writer, opts ...option) error

Variables

var (
	// ErrColNotFound is returned when a named column is not found.
	ErrColNotFound = errors.New("column not found")
	// ErrSameColName is returned when a named column exists multiple times.
	ErrSameColName = errors.New("multiple columns with same name")
	// ErrColLen is returned when the length of a column to add differs from the already existing dataset column length.
	ErrColLen = errors.New("length of columns differ")
)

Functions

func Delimiter

func Delimiter(delimiter rune) option

Delimiter is the separator between each value (default: ',').

func Equals

func Equals(datasetA, datasetB [][]string) bool

Equals checks if both datasets are the same.

func UseCLRF

func UseCLRF(useCLRF bool) option

UseCLRF is set to false by default. If set to true, the Writer ends each line with \r\n instead of \n.

Types

type Dataset

type Dataset struct {
	// contains filtered or unexported fields
}

Dataset contains the CSV content and eases modificating it.

func New

func New(dataset [][]string) Dataset

New creates a new CSV dataset.

func (*Dataset) AddCol

func (ds *Dataset) AddCol(column []string, index int) error

AddCol inserts the given column at the position of the index. -1 adds the column at the last column -2 adds the column as the second last column, and so on...

func (*Dataset) AddRow

func (ds *Dataset) AddRow(row []string) error

AddRow appends the given row to the dataset.

func (*Dataset) AddRows

func (ds *Dataset) AddRows(rows [][]string) error

AddRows appends the given rows to the dataset.

func (*Dataset) DeleteCol

func (ds *Dataset) DeleteCol(name string) error

DeleteCol deletes the column with the given name.

func (*Dataset) GetCol

func (ds *Dataset) GetCol(name string) ([]string, error)

GetCol returns the column with the given name.

func (*Dataset) ModifyCol

func (ds *Dataset) ModifyCol(name string, f func(val string, row int) string) error

ModifyCol changes the values of column 'name' according to 'f'. 'val' contains the column value and 'row' is the current row number.

func (*Dataset) MoveCol

func (ds *Dataset) MoveCol(name string, index int) error

MoveCol moves the given column to index.

func (*Dataset) Raw

func (ds *Dataset) Raw() [][]string

Raw returns the raw data usable with Go's stdlib csv package.

func (*Dataset) RenameCol

func (ds *Dataset) RenameCol(old, new string) error

RenameCol renames the header of column 'old' to 'new'.

func (*Dataset) Write

func (ds *Dataset) Write(writer io.Writer, opts ...option) error

Write the dataset to the given writer.