README
¶
Golang Library for UPC and EAN
A Go library for parsing, validating and analyzing UPCs and EAN-13/GTIN-13 codes.
- Validate the accuracy of UPC and EAN/GTIN codes.
- Parse UPC codes to determine the code type and other details (Manufacturer, Coupon Value, Product Code, etc)
Code Support
- UPC (Universal Product Code)
- EAN/GTIN 13 (European Article Numbering or Global Trade Item Number)
- JAN (Japanese Article Numbering)
The library works with 12 digit UPC (Universal Product Code) codes and 13 digit EAN (European Article Number) codes. EAN is also referred to as GTIN or Global Trade Item Number. The numbers are the same.
Usage
u, err := upc.Parse("045496830434")
if err == upc.ErrInvalidCheckDigit {
fmt.Println("There's a typo in the UPC")
} else if err != nil {
fmt.Printf("Something's wrong with the UPC: %s", err)
} else {
fmt.Printf("Number system: %d\n", u.NumberSystem())
fmt.Printf("Check digit: %d\n", u.CheckDigit())
if u.IsGlobalProduct() {
fmt.Printf("Manufacturer code: %d\n", u.Manufacturer())
fmt.Printf("Product code: %d\n", u.Product())
} else if u.IsDrug() {
fmt.Printf("Drug code: %d\n", u.Ndc())
} else if u.IsLocal() {
fmt.Println("UPC intended only for local use")
} else if u.IsCoupon() {
fmt.Printf("Manufacturer code: %d\n", u.Manufacturer())
fmt.Printf("Family code: %d\n", u.Family())
fmt.Printf("Coupon value: $0.%02d\n", u.Value())
} else {
panic("Preceeding categories are exhaustive")
}
}
Installation
go get -u github.com/vgpc/upc
Documentation
¶
Overview ¶
Package upc provides for parsing, validating and analyzing a UPC (Universal Product Code). For example,
u, err := upc.Parse("045496830434")
if err == upc.ErrInvalidCheckDigit {
fmt.Println("There's a typo in the UPC")
} else if err != nil {
fmt.Printf("Something's wrong with the UPC: %s", err)
} else {
fmt.Printf("Number system: %d\n", u.NumberSystem())
fmt.Printf("Check digit: %d\n", u.CheckDigit())
if u.IsGlobalProduct() {
fmt.Printf("Manufacturer code: %s\n", u.Manufacturer())
fmt.Printf("Product code: %d\n", u.Product())
} else if u.IsDrug() {
fmt.Printf("Drug code: %d\n", u.Ndc())
} else if u.IsLocal() {
fmt.Println("UPC intended only for local use")
} else if u.IsCoupon() {
fmt.Printf("Manufacturer code: %s\n", u.Manufacturer())
fmt.Printf("Family code: %d\n", u.Family())
fmt.Printf("Coupon value: $0.%02d\n", u.Value())
} else {
panic("Preceeding categories are exhaustive")
}
}
Index ¶
- Variables
- type Ean
- type Upc
- func (u Upc) CheckDigit() int
- func (u Upc) Family() int
- func (u Upc) IsCoupon() bool
- func (u Upc) IsDrug() bool
- func (u Upc) IsGlobalProduct() bool
- func (u Upc) IsLocal() bool
- func (u Upc) Manufacturer() string
- func (u Upc) Ndc() string
- func (u Upc) NumberSystem() int
- func (u Upc) Product() int
- func (u Upc) String() string
- func (u Upc) Value() int
Constants ¶
This section is empty.
Variables ¶
var ErrEanInvalidCheckDigit = errors.New("EAN has an invalid check digit")
var ErrEanTooLong = errors.New("EAN is too long (must be 13 digits)")
var ErrEanTooShort = errors.New("EAN is too short (must be 12 digits)")
var ErrInvalidCheckDigit = errors.New("UPC has an invalid check digit")
var ErrTooLong = errors.New("UPC is too long (must be 12 digits)")
var ErrTooShort = errors.New("UPC is too short (must be 12 digits)")
Functions ¶
This section is empty.
Types ¶
type Ean ¶
type Ean int64
Ean represents a European Article Number. To reduce memory consumption, it's stored as a 64-bit integer without the check digit.
func ParseEan ¶
Parse parses a string into a Ean value. The following errors can be returned in addition to integer parsing errors:
ErrEanTooShort ErrEanTooLong ErrEanInvalidCheckDigit
func (Ean) CheckDigit ¶
CheckDigit returns the check digit that should be used as the 13th digit of the EAN.
type Upc ¶
type Upc int64
Upc represents a Universal Product Code. To reduce memory consumption, it's stored as a 64-bit integer without the check digit.
func Parse ¶
Parse parses a string into a Upc value. The following errors can be returned in addition to integer parsing errors:
ErrTooShort ErrTooLong ErrInvalidCheckDigit
func (Upc) CheckDigit ¶
CheckDigit returns the check digit that should be used as the 12th digit of the UPC.
func (Upc) Family ¶
Family returns the coupon manufacturer's family code. It designates the kind of products to which the coupon applies.
func (Upc) IsCoupon ¶
IsCoupon returns true if the number system is 5. These UPCs are intended for labeling coupons. See Family and Value methods.
func (Upc) IsDrug ¶
IsDrug returns true if the number system is 3. These UPCs are intended for labeling drugs by their National Drug Council number. See Ndc method.
func (Upc) IsGlobalProduct ¶
IsGlobalProduct returns true if the number system is 0, 1, 6, 7, 8 or 9. These UPCs are intended for global use with products (in contrast to local use or coupon use, etc.)
func (Upc) IsLocal ¶
IsLocal returns true if the number system is 2 or 4. These UPCs are intended for local/warehouse use.
func (Upc) Manufacturer ¶
Manufacturer returns the 6-digit manufacturer code assigned by a GS1 organization. The return value is a string because leading zeros are used for lookups in the standard GS1 databases. In the case of coupons, the manufacturer is only 5 digits long.
func (Upc) Ndc ¶
Ndc returns the National Drug Code associated with a UPC. The value is only meaningful if IsDrug returns true for the UPC.
The value is a string because leading zeros are meaningful in the FDA database of labeler codes. No attempt is made to put the NDC code into standard format with dashes.
func (Upc) NumberSystem ¶
NumberSystem returns the first digit of the UPC, also known as the "number system".
Source Files