jmckaskill / go-capnproto Goto Github PK

    switch b[0] {
    case 0xFF:
        io.ReadFull(c.r, c.buf[:])
    case 0x00:

I think you need to read a byte and set c.raw after io.ReadFull. :-)

Not sure if this would be better on the main Cap'n Proto discussion, but I'll try here. How does one set a pointer in a list? I have a struct that looks like:

struct Map {
        map @0 :List(Item);
        struct Item {
                name @0 :Text;
                value :union {
                        int @1 :Int32;
                        string @2 :Text;
                        map @3 :Map;
                }
        }
}

I can create a Map. Then I create a MapItemList with the segment from the Map and the length that I want, and I set the MapItemList to the Map using SetMap(). I then use that segment to start creating MapItems, but I don't know how to set the pointers to my newly created MapItem's to their indexes in the MapItemList. If I print out the resulting bytes, I can see the data is there, but I can't get the data out of the list using the provided read functions, likely because I am not setting pointers to the data in the list. Here is the function I'm messing around with:

func WriteMap(mm map[string]interface{}) bytes.Buffer {
        ns := capn.NewBuffer(nil)
        m := NewRootMap(ns)
        mil := NewMapItemList(ns, len(mm))
        m.SetMap(mil)
        counter := 0
        for k, v := range mm {
                mi := NewMapItem(ns)
                mi.SetName(k)
                switch v.(type) {
                case string:
                        mi.Value().SetString(v.(string))
                case int:
                        mi.Value().SetInt(int32(v.(int)))
                default:
                        panic("OH SNAP")
                }
                counter++
        }
        buf := bytes.Buffer{}
        ns.WriteTo(&buf)
        return buf
}

Anyone see what I'm doing wrong? Or how I can do this?

Unions are only handled for struct union members. We should fix it so it handles all cases and also switch to using a switch statement.

I'm using a List(List(Signature)) where

struct Signature {                                                              
    key @0: Data;                                                               
    signature @1: Data;                                                         
}  

and the generated code cannot compile

capnp compile -ogo src/libnode/message.capnp
go install libnode
# libnode
src/libnode/message.capnp.go:1033: cannot range over s.ToArray() (type *[]capn.Object)
Makefile:21: recipe for target 'pkg/linux_amd64/libnode.a' failed

Can you write a sample for using packed streams?

I'm not sure if I'm missing something here but the union API seems to have changed since the documentation was written. Specifically the lines

f.SetA()         // Set that we are using group A
f.A().SetV(true) // then we can use the group A getter to set the inner values

http://godoc.org/github.com/jmckaskill/go-capnproto#hdr-Unions

Instead it seems to generate the following which can make the api harder to use

a := NewA((*C.Segment)s)
f.SetA(a A)
a.SetV(true)

Would it be worth generating a NewA() & NewB() on the containing Foo struct given it already has a reference to the segment and by definition they would never be a RootStruct.

This file should be removed from your repo:

https://github.com/jmckaskill/go-capnproto/blob/master/go_capnp_test/.test.go.swo

Is that possible to automatic prepend contents of go.capnp when generating go files?
As i see i need to have this file in all my projects and update when new version comes.