esdscom

Read, write and validate safety data sheets in the eSDScom exchange format (XML schema eSDSxml, formerly SDScomXML) with Go.

• Go types for the whole schema, generated from the official XSD, including the national extensions EU and DE
• Decode keeps content it does not know, Encode writes it back
• Validate reports every schema violation with its path, not only the first
• pure Go, standard library only, no cgo, no network access

Status

Version 0.x. The API may change until the first production use; see CHANGELOG.md.

Schema release	National extensions with Go types	Package version
eSDScom v5.5	EU, DE	v0.x

Content of the other national extensions (AR, AT, BR, CA, CH, DK, GB, JP, MX, NO, RU, TR, US) is kept unchanged and reported as a hint by Validate. The generator can produce their types as well.

Installation

go get github.com/velcure/esdscom

Usage

package main

import (
	"fmt"
	"log"
	"os"

	"github.com/velcure/esdscom"
)

func main() {
	f, err := os.Open("sds.xml")
	if err != nil {
		log.Fatal(err)
	}
	feed, err := esdscom.Decode(f) // esdscom.WithMaxSize, esdscom.DecodeStrict
	f.Close()
	if err != nil {
		log.Fatal(err)
	}

	for _, e := range feed.Validate() {
		// e.g. "error: Datasheet[0]/Composition/RegionEU/Component[0]/Substance/CasNo:
		//       "67-63-X" does not match the pattern ... (pattern)"
		fmt.Println(e)
	}

	for _, c := range feed.Datasheet[0].Composition.RegionEU.Choice.Component {
		fmt.Println(*c.Substance.CasNo)
	}

	if err := esdscom.Encode(os.Stdout, feed); err != nil {
		log.Fatal(err)
	}
}

How the schema maps to Go

XSD	Go
complex type	struct, fields in schema order, plus Extra for unknown content
element, at most once	pointer (*T); nil means absent
element, repeated	slice ([]T)
choice	struct with one field per alternative; exactly one is set
optional or repeated sequence	pointer to or slice of a struct
named group	struct of the group's name
extension	the base type's fields followed by the extension's
simple type	string type with constants for enumerations and Valid()
xs:boolean, xs:float, xs:date …	Boolean, Float, Date …, with Bool(), Float64(), Time()
element without type (xs:anyType)	AnyType, kept verbatim

Simple values keep their lexical form, so a malformed value never stops Decode; Validate reports it. esdscom.Ptr builds pointers to values.

Decode

• tolerant by default: unknown elements, attributes and text go to the Extra field of the enclosing struct, and Encode writes them back at the same position; DecodeStrict() makes them an error
• elements out of schema order are placed into their fields; Encode writes them in schema order
• input is limited to 64 MiB by default (WithMaxSize)
• documents with a document type declaration are rejected; no external entities or DTDs are ever loaded

Encode

Encode writes UTF-8 with the eSDScom namespace on the root element and all elements in schema order. When InformationFromExportingSystem has no SdscomVersionNo, it writes SchemaVersion there.

Validate

Validate checks required elements, occurrence limits, choices and all facets of simple types (enumerations, patterns, lengths, ranges, digits) and returns every finding with a path like Datasheet[0]/Identification/TradeName[1] and a rule name (required, enum, pattern, maxLength, choice, …). Unknown content kept in Extra is a hint (SeverityHint), not an error. The tests compare Validate with xmllint --schema on valid and deliberately broken documents.

Phrase codes are passed through; the phrase catalogue (eSDSphrac) is not part of this package.

Code generation

The types are generated from the vendored schema by cmd/esdscom-gen and committed:

go generate ./...

The generator supports exactly the XSD constructs the schema uses and stops at any other construct. See docs/schema-update.md for moving to a new schema release.

License

The code of this repository is licensed under the Apache License 2.0.

The eSDScom XML schema in schema/ is © the eSDScom project and licensed under CC BY-ND 4.0. It is included unchanged; see NOTICE and schema/v5.5/NOTICE.