diff --git a/cmd/policy/main.go b/cmd/policy/main.go
index f941473116eae58d78626bab031c280dd8e1846f..f718301b8d3e1deddbf3cd285d2fe6fb1b3a03b3 100644
--- a/cmd/policy/main.go
+++ b/cmd/policy/main.go
@@ -87,6 +87,7 @@ func main() {
taskFuncs := regofunc.NewTaskFuncs(cfg.Task.Addr, httpClient)
ocmFuncs := regofunc.NewOcmFuncs(cfg.OCM.Addr, httpClient)
signerFuncs := regofunc.NewSignerFuncs(cfg.Signer.Addr, httpClient)
+ didTransformerFuncs := regofunc.NewDIDTransformerFuncs()
regofunc.Register("cacheGet", rego.Function3(cacheFuncs.CacheGetFunc()))
regofunc.Register("cacheSet", rego.Function4(cacheFuncs.CacheSetFunc()))
regofunc.Register("didResolve", rego.Function1(didResolverFuncs.ResolveFunc()))
@@ -99,6 +100,8 @@ func main() {
regofunc.Register("verifyProof", rego.Function1(signerFuncs.VerifyProof()))
regofunc.Register("ocmLoginProofInvitation", rego.Function2(ocmFuncs.GetLoginProofInvitation()))
regofunc.Register("ocmLoginProofResult", rego.Function1(ocmFuncs.GetLoginProofResult()))
+ regofunc.Register("didToURL", rego.Function1(didTransformerFuncs.ToURLFunc()))
+ regofunc.Register("urlToDID", rego.Function1(didTransformerFuncs.FromURLFunc()))
}
// subscribe the cache for policy data changes
diff --git a/internal/regofunc/did_transformer.go b/internal/regofunc/did_transformer.go
new file mode 100644
index 0000000000000000000000000000000000000000..dbd390726627998388edfd2c4d21c8af1d508b3a
--- /dev/null
+++ b/internal/regofunc/did_transformer.go
@@ -0,0 +1,145 @@
+package regofunc
+
+import (
+ "fmt"
+ "net/url"
+ "strings"
+
+ "github.com/open-policy-agent/opa/ast"
+ "github.com/open-policy-agent/opa/rego"
+ "github.com/open-policy-agent/opa/types"
+ "gitlab.com/gaia-x/data-infrastructure-federation-services/tsa/golib/errors"
+)
+
+const (
+ didSeparator = ":"
+ urlSeparator = "/"
+ defaultUrlPath = ".well-known"
+)
+
+type DIDTransformerFuncs struct{}
+
+type DID struct {
+ scheme string // scheme is always "did"
+ method string // method is the specific did method - "web" in this case
+ path string // path is the unique URI assigned by the DID method
+}
+
+func NewDIDTransformerFuncs() *DIDTransformerFuncs {
+ return &DIDTransformerFuncs{}
+}
+
+func (dt *DIDTransformerFuncs) ToURLFunc() (*rego.Function, rego.Builtin1) {
+ return ®o.Function{
+ Name: "url_from_did",
+ Decl: types.NewFunction(types.Args(types.S), types.A),
+ Memoize: true,
+ },
+ func(bctx rego.BuiltinContext, a *ast.Term) (*ast.Term, error) {
+ var did string
+
+ if err := ast.As(a.Value, &did); err != nil {
+ return nil, fmt.Errorf("invalid DID: %s", err)
+ }
+ if did == "" {
+ return nil, errors.New("DID cannot be empty")
+ }
+
+ u, err := dt.didToURL(did)
+ if err != nil {
+ return nil, err
+ }
+
+ return ast.StringTerm(u.String()), nil
+ }
+}
+
+func (dt *DIDTransformerFuncs) FromURLFunc() (*rego.Function, rego.Builtin1) {
+ return ®o.Function{
+ Name: "did_from_url",
+ Decl: types.NewFunction(types.Args(types.S), types.A),
+ Memoize: true,
+ },
+ func(bctx rego.BuiltinContext, a *ast.Term) (*ast.Term, error) {
+ var u string
+
+ if err := ast.As(a.Value, &u); err != nil {
+ return nil, fmt.Errorf("invalid URL: %s", err)
+ }
+ if u == "" {
+ return nil, errors.New("URL cannot be empty")
+ }
+ uri, err := url.Parse(u)
+ if err != nil {
+ return nil, errors.New("cannot parse URL")
+ }
+ if uri.Host == "" || uri.Scheme != "https" {
+ return nil, errors.New("invalid URL for did:web method")
+ }
+
+ did := dt.urlToDID(uri)
+
+ return ast.StringTerm(did.String()), nil
+ }
+}
+
+// didToURL transforms a valid DID, created by the "did:web" Method Specification, to a URL.
+// Documentation can be found here: https://w3c-ccg.github.io/did-method-web/
+func (dt *DIDTransformerFuncs) didToURL(DID string) (*url.URL, error) {
+ ss := strings.Split(DID, didSeparator)
+ if len(ss) < 3 {
+ return nil, errors.New("invalid DID, host is not found")
+ }
+ if ss[0] != "did" || ss[1] != "web" {
+ return nil, errors.New("invalid DID, method is unknown")
+ }
+
+ path := defaultUrlPath
+ if len(ss) > 3 {
+ path = ""
+ for i := 3; i < len(ss); i++ {
+ path = path + urlSeparator + ss[i]
+ }
+ }
+ path = path + urlSeparator + "did.json"
+
+ host, err := url.PathUnescape(ss[2])
+ if err != nil {
+ return nil, errors.New("failed to url decode host from DID")
+ }
+
+ return &url.URL{
+ Scheme: "https",
+ Host: host,
+ Path: path,
+ }, nil
+}
+
+// urlToDID transforms a valid URL to a DID created following the "did:web" Method Specification.
+// Documentation can be found here: https://w3c-ccg.github.io/did-method-web/
+func (dt *DIDTransformerFuncs) urlToDID(uri *url.URL) *DID {
+ p := strings.TrimRight(uri.Path, "did.json")
+ sp := strings.Split(p, urlSeparator)
+
+ path := url.QueryEscape(uri.Host)
+ for _, v := range sp {
+ if v == defaultUrlPath {
+ break
+ }
+ if v == "" {
+ continue
+ }
+ path = path + didSeparator + url.QueryEscape(v)
+ }
+
+ return &DID{
+ scheme: "did",
+ method: "web",
+ path: strings.Trim(path, didSeparator),
+ }
+}
+
+// String returns a string representation of this DID.
+func (d *DID) String() string {
+ return fmt.Sprintf("%s:%s:%s", d.scheme, d.method, d.path)
+}
diff --git a/internal/regofunc/did_transformer_test.go b/internal/regofunc/did_transformer_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..4fed242c83653999796f87c7823d246f86039d16
--- /dev/null
+++ b/internal/regofunc/did_transformer_test.go
@@ -0,0 +1,142 @@
+package regofunc_test
+
+import (
+ "context"
+ "encoding/json"
+ "testing"
+
+ "github.com/open-policy-agent/opa/rego"
+ "github.com/stretchr/testify/assert"
+ "gitlab.com/gaia-x/data-infrastructure-federation-services/tsa/policy/internal/regofunc"
+)
+
+func TestToURLFunc(t *testing.T) {
+ tests := []struct {
+ // test input
+ name string
+ regoQuery string
+ // expected result
+ res string
+ errText string
+ }{
+ {
+ name: "DID is empty",
+ regoQuery: `url_from_did("")`,
+ errText: "DID cannot be empty",
+ },
+ {
+ name: "invalid DID",
+ regoQuery: `url_from_did("invalid-did")`,
+ errText: "invalid DID, host is not found",
+ },
+ {
+ name: "invalid DID Method",
+ regoQuery: `url_from_did("did:sov:123456qwerty")`,
+ errText: "invalid DID, method is unknown",
+ },
+ {
+ name: "transformation success with DID containing domain only",
+ regoQuery: `url_from_did("did:web:w3c-ccg.github.io")`,
+ res: "\"https://w3c-ccg.github.io/.well-known/did.json\"",
+ },
+ {
+ name: "transformation success with DID containing domain and path",
+ regoQuery: `url_from_did("did:web:w3c-ccg.github.io:user:alice")`,
+ res: "\"https://w3c-ccg.github.io/user/alice/did.json\"",
+ },
+ {
+ name: "transformation success with DID containing network port",
+ regoQuery: `url_from_did("did:web:example.com%3A3000:user:alice")`,
+ res: "\"https://example.com:3000/user/alice/did.json\"",
+ },
+ }
+
+ for _, test := range tests {
+ t.Run(test.name, func(t *testing.T) {
+ DIDTransformerFuncs := regofunc.NewDIDTransformerFuncs()
+
+ r := rego.New(
+ rego.Query(test.regoQuery),
+ rego.Function1(DIDTransformerFuncs.ToURLFunc()),
+ rego.StrictBuiltinErrors(true),
+ )
+ resultSet, err := r.Eval(context.Background())
+
+ if err == nil {
+ resultBytes, err := json.Marshal(resultSet[0].Expressions[0].Value)
+ assert.NoError(t, err)
+ assert.Equal(t, test.res, string(resultBytes))
+ } else {
+ assert.ErrorContains(t, err, test.errText)
+ }
+ })
+ }
+}
+
+func TestFromURLFunc(t *testing.T) {
+ tests := []struct {
+ // test input
+ name string
+ regoQuery string
+ // expected result
+ res string
+ errText string
+ }{
+ {
+ name: "empty URL",
+ regoQuery: `did_from_url("")`,
+ errText: "URL cannot be empty",
+ },
+ {
+ name: "URL containing special characters",
+ regoQuery: `did_from_url("example.com\nH1234")`,
+ errText: "cannot parse URL",
+ },
+ {
+ name: "URL does not contain secure protocol (https)",
+ regoQuery: `did_from_url("example.com")`,
+ errText: "invalid URL for did:web method",
+ },
+ {
+ name: "URL does not contain valid domain",
+ regoQuery: `did_from_url("https://")`,
+ errText: "invalid URL for did:web method",
+ },
+ {
+ name: "transformation success with URL containing domain only",
+ regoQuery: `did_from_url("https://w3c-ccg.github.io/.well-known/did.json")`,
+ res: "\"did:web:w3c-ccg.github.io\"",
+ },
+ {
+ name: "transformation success with URL containing domain with path",
+ regoQuery: `did_from_url("https://w3c-ccg.github.io/user/alice/did.json")`,
+ res: "\"did:web:w3c-ccg.github.io:user:alice\"",
+ },
+ {
+ name: "transformation success with URL containing network port",
+ regoQuery: `did_from_url("https://example.com:3000/user/alice/did.json")`,
+ res: "\"did:web:example.com%3A3000:user:alice\"",
+ },
+ }
+
+ for _, test := range tests {
+ t.Run(test.name, func(t *testing.T) {
+ DIDTransformerFuncs := regofunc.NewDIDTransformerFuncs()
+
+ r := rego.New(
+ rego.Query(test.regoQuery),
+ rego.Function1(DIDTransformerFuncs.FromURLFunc()),
+ rego.StrictBuiltinErrors(true),
+ )
+ resultSet, err := r.Eval(context.Background())
+
+ if err == nil {
+ resultBytes, err := json.Marshal(resultSet[0].Expressions[0].Value)
+ assert.NoError(t, err)
+ assert.Equal(t, test.res, string(resultBytes))
+ } else {
+ assert.ErrorContains(t, err, test.errText)
+ }
+ })
+ }
+}