docs: add missing documentation to functions

services/collaboration/pkg/middleware/claims.go

@@ -2,6 +2,7 @@ package middleware
 
 import "github.com/golang-jwt/jwt/v4"
 
+// Claims contains the jwt registered claims plus the used WOPI context
 type Claims struct {
 	WopiContext WopiContext `json:"WopiContext"`
 	jwt.RegisteredClaims

services/collaboration/pkg/middleware/crypto.go

@@ -9,6 +9,9 @@ import (
 	"io"
 )
 
+// keyPadding will add the required zero padding to the provided key.
+// The resulting key will have a length of either 16, 24 or 32 bytes.
+// If the key has more than 32 bytes, only the first 32 bytes will be returned.
 func keyPadding(key []byte) []byte {
 	switch length := len(key); {
 	case length < 16:
@@ -29,6 +32,9 @@ func keyPadding(key []byte) []byte {
 	return []byte{}
 }
 
+// EncryptAES encrypts the provided plainText using the provided key.
+// AES CFB will be used as cryptographic method.
+// Use DecryptAES to decrypt the resulting string
 func EncryptAES(key []byte, plainText string) (string, error) {
 	src := []byte(plainText)
 
@@ -49,6 +55,9 @@ func EncryptAES(key []byte, plainText string) (string, error) {
 	return base64.URLEncoding.EncodeToString(cipherText), nil
 }
 
+// DecryptAES decrypts the provided string using the provided key.
+// The provided string must have been encrypted with AES CFB.
+// This method will decrypt the result from the EncryptAES method
 func DecryptAES(key []byte, securemess string) (string, error) {
 	cipherText, err := base64.URLEncoding.DecodeString(securemess)
 	if err != nil {

services/collaboration/pkg/middleware/wopicontext.go

@@ -21,6 +21,7 @@ const (
 	wopiContextKey key = iota
 )
 
+// WopiContext wraps all the information we need for WOPI
 type WopiContext struct {
 	AccessToken   string
 	FileReference providerv1beta1.Reference
@@ -30,6 +31,17 @@ type WopiContext struct {
 	ViewAppUrl    string
 }
 
+// WopiContextAuthMiddleware will prepare an HTTP handler to be used as
+// middleware. The handler will create a WopiContext by parsing the
+// access_token (which must be provided as part of the URL query).
+// The access_token is required.
+//
+// This middleware will add the following to the request's context:
+// * The access token as metadata for outgoing requests (for the
+// authentication against the CS3 API, the "x-access-token" header).
+// * The created WopiContext for the request
+// * A contextual zerologger containing information about the request
+// and the WopiContext
 func WopiContextAuthMiddleware(jwtSecret string, next http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		accessToken := r.URL.Query().Get("access_token")