grate

A Go native tabular data extraction package. Currently supports .xls, .xlsx, .csv, .tsv formats.

Why?

Grate focuses on speed and stability first, and makes no attempt to parse charts, figures, or other content types that may be present embedded within the input files. It tries to perform as few allocations as possible and errs on the side of caution.

There are certainly still some bugs and edge cases, but we have run it successfully on a set of 400k .xls and .xlsx files to catch many bugs and error conditions. Please file an issue with any feedback and additional problem files.

Usage

Grate provides a simple standard interface for all supported filetypes, allowing access to both named worksheets in spreadsheets and single tables in plaintext formats.

Opening from File

package main

import (
    "fmt"
    "os"
    "strings"

    "github.com/constshift/grate"
    _ "github.com/constshift/grate/simple" // tsv and csv support
    _ "github.com/constshift/grate/xls"
    _ "github.com/constshift/grate/xlsx"
)

func main() {
    wb, _ := grate.Open(os.Args[1])  // open the file
    sheets, _ := wb.List()           // list available sheets
    for _, s := range sheets {       // enumerate each sheet name
        sheet, _ := wb.Get(s)        // open the sheet
        for sheet.Next() {           // enumerate each row of data
            row := sheet.Strings()   // get the row's content as []string
            fmt.Println(strings.Join(row, "\t"))
        }
    }
    wb.Close()
}

Opening from Memory

Grate supports opening files directly from memory, which is useful for processing data from HTTP requests, embedded files, or other sources without writing to disk.

package main

import (
    "fmt"
    "io"
    "os"

    "github.com/constshift/grate"
    _ "github.com/constshift/grate/simple"
    _ "github.com/constshift/grate/xls"
    _ "github.com/constshift/grate/xlsx"
)

func main() {
    d, _ := os.ReadFile(os.Args[1])  // Read file into memory
    wb, _ := grate.OpenBytes(d)      // open the file
    sheets, _ := wb.List()           // list available sheets
    for _, s := range sheets {       // enumerate each sheet name
        sheet, _ := wb.Get(s)        // open the sheet
        for sheet.Next() {           // enumerate each row of data
            row := sheet.Strings()   // get the row's content as []string
            fmt.Println(strings.Join(row, "\t"))
        }
    }
    wb.Close()
}

License

All source code is licensed under the MIT License.