The goal of this package is to preload xsd files into memory and to validate xml (fast) using libxml2, like post bodys of xml service endpoints or api routers. At the time of writing, similar packages I found on github either didn't provide error details or got stuck under load. In addition to providing error strings it also exposes some fields of libxml2 return structs.
https://godoc.org/github.com/terminalstatic/go-xsd-validate
Install libxml2 dev via distribution package manager or from source, below an example how to install the latest libxml2 from source on linux(Debian/Ubuntu):
curl -L ftp://xmlsoft.org/libxml2/LATEST_LIBXML2 -o ./LIBXML2_LATEST.tar.gz
tar -xf ./LIBXML2_LATEST.tar.gz
cd ./libxml2*
./configure --prefix=/usr --enable-static --with-threads --with-history
make
sudo make install
Go get the package:
go get github.com/terminalstatic/go-xsd-validate
Check this for a simple http server example and that for an even simpler one. Look at this for an example using Go's embed
package to bake an XML schema into a simple http server.
To see how this could be plugged into middleware see the go-chi example I came up with.
xsdvalidate.Init()
defer xsdvalidate.Cleanup()
xsdhandler, err := xsdvalidate.NewXsdHandlerUrl("examples/test1_split.xsd", xsdvalidate.ParsErrDefault)
if err != nil {
panic(err)
}
defer xsdhandler.Free()
xmlFile, err := os.Open("examples/test1_fail2.xml")
if err != nil {
panic(err)
}
defer xmlFile.Close()
inXml, err := ioutil.ReadAll(xmlFile)
if err != nil {
panic(err)
}
// Option 1:
xmlhandler, err := xsdvalidate.NewXmlHandlerMem(inXml, xsdvalidate.ParsErrDefault)
if err != nil {
panic(err)
}
defer xmlhandler.Free()
err = xsdhandler.Validate(xmlhandler, xsdvalidate.ValidErrDefault)
if err != nil {
switch err.(type) {
case xsdvalidate.ValidationError:
fmt.Println(err)
fmt.Printf("Error in line: %d\n", err.(xsdvalidate.ValidationError).Errors[0].Line)
fmt.Println(err.(xsdvalidate.ValidationError).Errors[0].Message)
default:
fmt.Println(err)
}
}
// Option 2:
err = xsdhandler.ValidateMem(inXml, xsdvalidate.ValidErrDefault)
ifT err != nil {
switch err.(type) {
case xsdvalidate.ValidationError:
fmt.Println(err)
fmt.Printf("Error in line: %d\n", err.(xsdvalidate.ValidationError).Errors[0].Line)
fmt.Println(err.(xsdvalidate.ValidationError).Errors[0].Message)
default:
fmt.Println(err)
}
}