There are installable packages on the interenet, with Maintainer or Description missing.

[ebikt]

Downloaded some packages from internet, and installed them to my machines and needed my software to be able to parse them (possibly with warnings.).

[paultag]

I had a similar issue, but I wonder if a better fix would be to drop an error that can be ignored when a required field is missing. At the end of the day, dpkg will complain quite a bit, it's invalid - and i'm split on what to do. I'm going to think about this one a bit more.

Would something like the code below have been enough to work around your issue parsing invalid debs?

diff --git a/control/decode.go b/control/decode.go
index 649b48a..66cf38d 100644
--- a/control/decode.go
+++ b/control/decode.go
@@ -21,6 +21,7 @@
 package control // import "pault.ag/go/debian/control"

 import (
+       "errors"
        "fmt"
        "io"
        "reflect"
@@ -103,6 +104,8 @@ func (d *Decoder) Decode(into interface{}) error {
        return decode(&d.paragraphReader, reflect.ValueOf(into))
 }

+var MissingField = errors.New("debian: control: Required field is missing!")
+
 // Top-level decode dispatch {{{

 func decode(p *ParagraphReader, into reflect.Value) error {
@@ -185,10 +188,7 @@ func decodeStruct(p Paragraph, into reflect.Value) error {
                        continue
                } else {
                        if fieldType.Tag.Get("required") == "true" {
-                               return fmt.Errorf(
-                                       "Required field '%s' is missing!",
-                                       fieldType.Name,
-                               )
+                               return MissingField
                        }
                        continue
                }

[paultag]

Actually scratch that, this still wouldn't return the control. Nevermind. I'm still going to think about it, but I may accept this or make the required something that you can opt-in to enforce or opt-out of enforcing. Hang tight on this one