Provides tools to help set Go structures from CSV lines / files and vice versa.
Installation
To install assertions run:
$ go get github.com/rzajac/csvutil
Documentation
Set fields from CSV
Here we are setting person fields from CSV. The columns in CSV line must be in the same order as fields in the structure (from top to bottom). You may skip fields by tagging them with csv:"-".
import ( "github.com/rzajac/csvutil" ) var testCsvLines = []string{"Tony|23|123.456|Y", "John|34|234.567|N|"} type person struct { Name string Age int Skipped string `csv:"-"` // Skip this field when setting the structure Balance float32 LowBalance bool } main () { // This can be any io.ReadCloser() interface sr := csvutil.StringReadCloser(strings.Join(testCsvLines, "\n")) // Set delimiter to '|', allow for trailing comma and do not check fields per CSV record c := csvutil.NewCsvUtil(sr).Comma('|').TrailingComma(true).FieldsPerRecord(-1).CustomBool([]string{"Y"}, []string{"N"}) // Struct we will populate with CSV data p := &person{Skipped: "aaa"} // Set values from CSV line to person structure err := c.SetData(p) // Do work with p // Set values from the second CSV line err := c.SetData(p) }
Picking only CSV columns we are interested in
type person2 struct { Name string Balance float32 } main () { sr := csvutil.StringReadCloser(strings.Join(testCsvLines, "\n")) // Set delimiter to '|', allow for trailing comma and do not check fields per CSV record c := csvutil.NewCsvUtil(sr).Comma('|').TrailingComma(true).FieldsPerRecord(-1) // Set header with column names matching structure fields and column indexes on the CSV line. // The indexes in the CSV line start with 0. c.Header(map[string]int{"Name": 0, "Balance": 2}) // Struct we wil lpopulate with data p := &person2{} // Set values from CSV line to person2 structure err := c.SetData(p) // Do work with p // Set values from the second CSV line err := c.SetData(p) }
Custom true / false values
CustomBool() method allows you to set custom true / false values in CSV columns.
main () { sr := csvutil.StringReadCloser("Y|N") c := csvutil.NewCsvUtil(sr).CustomBool([]string{"Y"}, []string{"N"}) }
Trim CSV column values before assigning to structure field
c := csvutil.NewCsvUtil(sr).Trim(" ") // Trim spaces from beginning and the end of volumn value c := csvutil.NewCsvUtil(sr).Trim(" *") // Trim spaces and asterisks from beginning and the end of volumn value
Create CSV line from struct
p := &person{"Tom", 45, "aaa", 111.22, true} csvLine, err := csvutil.ToCsv(p, "|", "YY", "NN") fmt.Println(csvLine) // Prints: Tom|45|111.22|YY
Getting last CSV line that have been read form the file
... p := &person2{} err := c.SetData(p) csvLine := c.LastCsvLine()
TODO
- Add writing CSV to file
License
Released under the MIT License. CSVUtil (c) Rafal Zajac rzajac@gmail.com