gotosocial/vendor/github.com/superseriousbusiness/activity/streams/util.go
2021-11-13 17:29:43 +01:00

66 lines
1.7 KiB
Go

package streams
import (
"github.com/superseriousbusiness/activity/streams/vocab"
)
const (
// jsonLDContext is the key for the JSON-LD specification's context
// value. It contains the definitions of the types contained within the
// rest of the payload. Important for linked-data representations, but
// only applicable to go-fed at code-generation time.
jsonLDContext = "@context"
)
// Serialize adds the context vocabularies contained within the type
// into the JSON-LD @context field, and aliases them appropriately.
func Serialize(a vocab.Type) (m map[string]interface{}, e error) {
m, e = a.Serialize()
if e != nil {
return
}
v := a.JSONLDContext()
// Transform the map of vocabulary-to-aliases into a context payload,
// but do so in a way that at least keeps it readable for other humans.
var contextValue interface{}
if len(v) == 1 {
for vocab, alias := range v {
if len(alias) == 0 {
contextValue = vocab
} else {
contextValue = map[string]string{
alias: vocab,
}
}
}
} else {
var arr []interface{}
aliases := make(map[string]string)
for vocab, alias := range v {
if len(alias) == 0 {
arr = append(arr, vocab)
} else {
aliases[alias] = vocab
}
}
if len(aliases) > 0 {
arr = append(arr, aliases)
}
contextValue = arr
}
// TODO: Update the context instead if it already exists
m[jsonLDContext] = contextValue
// TODO: Sort the context based on arbitrary order.
// Delete any existing `@context` in child maps.
var cleanFnRecur func(map[string]interface{})
cleanFnRecur = func(r map[string]interface{}) {
for _, v := range r {
if n, ok := v.(map[string]interface{}); ok {
delete(n, jsonLDContext)
cleanFnRecur(n)
}
}
}
cleanFnRecur(m)
return
}