►
From YouTube: TokenScript design weekly 20200102
Description
Hi everyone. In the last meeting, thanks to being in Christmas, we
only covered learnability topics, like how to segment tokenscript for
learnability and how to name the components for learnability. None
were concluded and I'll summarize them later in the forum.
Today's meeting continues from previous attestation discussion
- I will demonstrate a small test case of DER based TokenScript
parsing, written in JAVA. A previous test case was written in Solidity
by James Brown but that was before we have had an ASN.1 module for
attestation so I'll ask James to update his test case.
-URI schema for attestations, pick up from here:
https://community.tokenscript.org/t/a-uri-schema-for-attestations/303
Optionally:
- smart-contract interface of attestations.
A
A
B
A
Well
originally
intended
to
present
the
dar
pasa
and
that
I
implemented
as
a
AWS
lambda,
but-
and
that
is
not
important
now,
because,
if
we're
not
using
attestation
in
our
project,
the
implementation
is
not
important.
Only
the
design
is
so.
We
may
as
well
skip
that
okay,
so
we
help
our
design
stuff.
When
we
come
to
the
point
of
implementation,
I
will
talk
about
implementation,
like
which
two
works,
two
extension,
so
the
design
is
mostly
the
URL
schema
and
smart
contract
interface.
I
didn't
get
around
to
prepare
smart
control
interface.
C
A
C
A
Tall
and
remember
a
while
ago,
like
like
in
December
I
mentioned,
so
we
set
out
to
do
different
things.
I
asked
you
to
produce
a
the
er
paste
password
based
on
my
schema
and
sorry.
Yes,
not
one
module
and
I
set
out
to
do
the
same,
but
on
Java
instead
and
I
have
done
my
part,
and
you
have
done
your
part.
I.
A
Think
you
sent
me
that
it's
my
contract
code,
which
I
didn't
test
and
I,
have
a
written,
a
java-based,
yes
and
not
one
passer
implemented
were
not
written
one
and
then
deployed
deployed
it
AWS
as
a
lambda.
So
that
idea
is
applications
can
call
the
lambda
by
sending
the
dr
and
then
each
who
returns
to
trace
interpretation.
This
is
so
that
Android
and
iOS
can
use
it
at
the
same
time
without
him
right
implementation
separately
as
middle
stage,
and
then
that
work
is
done.
A
A
So,
thank
you
for
delivering
time
and
sorry
for
not
using
it,
because
the
project
direction
changes
slowly
is
largely
well.
What
can
I
invent
supporting
next
three
weeks
now,
because
we
are
not
implementing
attestation
in
this
month,
I
think
today
we
will
simply
talk
about
design
and
not
implementation.
A
Originally,
what
wanted
to
present
the
the
day,
WS
implementation
and
talk
with
you
about
the
smart
contract
implementation,
but
thanks
for
the
recent
change
in
priority,
let's
discard
that
and
just
look
at
design,
so
the
piece
of
design
I
want
you
to
look
to
have
have
a
look
at
today
is
the
one
I
mentioned.
The
email,
I
also
posted
message
here
in
the
chat
room.
A
Okay,
so
basically,
this
is
about
how
to
deliver
attestation
and
by
URL.
So
I'll
give
you
a
scenario.
That's
suppose
you
have
a
crypto
kitty
and
they
want
to
sell
it
for
three
ethers.
What
you
can
do
is
to
generate
a
link
which
is
a
signed
message,
which
is
attestation
since
that
you
are
willing
to
sell
your
kitty
for
three
either's
and
that
is
assigned
attestation
that
you
can
send
to
a
friend
your
friend
who
wants
to
buy
it
with
readers.
A
A
It
can
be
anything
basically,
attestation
is
needed,
parameter
for
next
transaction
and
all
itself
can
be
delivered
through
and
through
through
link
to
some
other
people.
For
example,
if
you,
if
I
request
you,
if
you
are
Authority
and
I'm,
a
user
I
will
request
a
attestation
of
my
ownership
of
email
address
to
you
and
you
might
deliver
that
attestation
in
the
form
of
a
link
and
it's
simply
imported.
A
Right,
okay,
so
just
this
is
why
we
have
a
URI
or
schema
for
attestations.
So
not
let's
look
at
this
message
and
I
will
walk
you
through
this
and
Pune
following
yes,
okay,
so
I
first
presented
a
very
basic
attestation,
which
is
station
colon,
followed
by
a
smart
contract,
which
the
castration
is
relevant,
of
followed
by
the
test.
Asian
itself,
which
is
the
ER
then
encoded
in
base64,
which
is
a
yah
right.
A
A
So
that's
all
right!
All
right!
Then.
If
we
go
on
go
down
from
here,
this
is
apparently
too
long.
So
the
rest
of
the
text
is
about
how
to
shorten
it
and
so
to
shorten
it.
And
let's
look
at
what
is
inside
attestation,
look
at
the
JSON
representation.
Okay,
sorry
I
spelled
it
as
JSON,
but
you
know
what
I
mean
is
JSON
should
be
jeaious
and
just
search
for
the
word
Jaso
and.
A
A
A
A
Yes,
okay,
so
what's
in
it
is
first
attestation
protocol
header,
followed
by
0
X.
That's
the
smart
contract
that
is
relevant,
followed
by
a
match.
Id
match
equals
to
1
class
equals
to
launch
admission
equals
to
1
that's
a
ticket,
that's
the
data
object
and
then
followed
by
the
signature,
which
is
led
almost
2
lines,
long
right
right.
A
So
this
is
possible
because
the
data
type
of
match
1,
for
example,
is
an
integer
and
the
class
equals
to
launch
launch
is
a
let's
say,
unit
string.
So
the
type
of
this
is
embedded
in
schema.
So
so
so
you
can
reconstruct
this
attestation
in
memory
and
then
attach
signature
Kings.
This
in
memory
test
stage.
B
A
A
So
because,
when
it's
on
a
web,
the
some
some
of
the
some
JavaScript
will
mistakenly
think
that
the
plus
symbol
in
base64
is
special
meaning,
but
actually
it's
just
part
of
the
URL
I.
Don't
want
to
break
any
URL
recognition,
JavaScript
or
web
stuff.
So
I
want
to
use
safe
character
set
for
base64
and
for
mobile
friendly
I
mean
that
mobile
phone
has
flexibility
of
new
protocol
headers.
You
cannot
define
stuff
like
attestation.
A
B
A
B
A
B
Doesn't
help
because
the
rich
F
gets
lunch
is
not
predictable
and
if
you
use,
if
you
wrap
it
with
HTTP
or
HTTPS
URL
scheme,
the
the
problem
is
in
your
example:
you're
using
attestation
on
ID.
That
means
the
owner
of
attestation,
which
is
me
yes,
we
have
to
specify
which
other
apps
which
can
handle
for
this,
which
means
that
if
there
is
a
third-party
application
app
which
ones
to
handle
this,
they
have
to
go
to
you.
You
have
to
get
permission.
A
A
A
So
problem
number
one
is
in
this
version:
I
have
left
out
public
key
because
it
can
be
recovered
in
from
the
signature,
and
it
is
usually
done
in
theorem,
I
mentioned
before
that
in
some
transaction.
Usually
you
put
a
signature
there
and
you
don't
put
public
key.
Instead,
the
client
was
whoever
receives.
A
It
was
supposed
to
reconstruct
the
public
key
from
it,
but
it's
possible
to
to
reconstruct
more
than
one
possible
public
keys
from
the
signature,
RS
value
and
somehow
the
third
value
is
used
as
B
B,
which
is
a
selector
which
indicate
which
of
the
possible
public
key
is
reconstructed,
is
going
to
be
used
as
a
real
public
key.
Now
there
is
a
problem
of
how
to
encode
B.
A
If
we
leave
out
publicly
in
the
URL
okay,
so
basically
I
don't
have
a
solution
for
that.
One
solution
is
simply
inserted
into
the
signature,
but
that
that
makes
the
signature
incompatible
with
our
FC,
which
means
when
you
produce
a
in
memory
representation
of
the
test.
Ation,
it's
not
going
to
reuse
the
same
thing
that
is
in
the
link
as
a
signature.
We
would
use
a
modified
version
of
it,
which
is
confusing
and
I,
don't
know,
maybe
not
so
good,
and
the
other
idea
is
to
use
the
separators.
A
A
And
and
the
the
current
way
that
is
encoded
into
a
sequence
you
can
see
by
RFC
for
5
for
H
0
and
the
current
weight
is
encoded
in
sequence.
Is
the
same
format
that
you
would
see
in
x.509,
for
example,
traditional
attestations.
So
if
we
change
it
into
R
equal
to
s,
equal
to
V
varies
translation
going
out,
which
is
not
bad
either,
so
that
yeah,
that's
that's
what,
because
every
other
solution
is
also
not
good.
So
maybe
we
simply
encode
R
equal
to
something
s
equal
to
something
being
equal
to
something.
C
A
C
A
A
B
A
B
A
A
Okay
and
anyway,
and
the
second
I
proceed
on
because
it
seems
like
we
just-
did
only
have
a
handful
of
not
very
perfect
solutions.
Yes,
okay,
so
so,
then
the
next
one
is
encoding.
Action
so
and
I
wish
to
solve
this
by
design
I
can
is
it
possible
that
we
don't
encode
actions
if
we
can't
:
code
action?
I
presented
the
example
where
the
word
by
B
or
Y
is
encoded
in
URL,
but
I
really
I
wanted
to
to
to
to
program
the
actions
into
the
test
ation.
A
The
link
has
three
lines.
I
will
looking
at
the
same
link:
yes,
okay,
we
by
question
yeah.
Yes,
so
one
way
to
design
it
is
Alice.
Since
this
his
it
has
to
heard
attestation
that
she
owns
the
ticket
and
send
this
thing
in
with
a
by
action,
so
the
by
action
in
token
script
would
be
activated
asking
Bob
to
sign
something
like
he's
ready
to
buy
it.
And
then
this
are
our
back.
Bob
can
take
this
a
test.
Sorry
Bob
can
sign.
A
Some
can
offer
to
buy
it
by
placing
the
cost
the
the
amount
he
is
willing
to
pay
and
then
send
something
back
to
Alice,
and
then
Alice
is
able
to
to
include
that
in
smart
contract
transaction
or
maybe
it
should
be
done.
The
other
way
around,
where
Alice
will
simply
send
attestation
to
Bob,
to
show
that
he
has
this
ticket
a
ticket
and
then.
A
Bob
is
going
to
purchase
it
and
he
will
refer
to
this
attestation
in
his
own
signed
message.
For
example,
tickets
to
buy
value
equals
to
the
hash
of
the
attestation
Alice
sent
to
Bob,
and
then
Alice
can
send
this
to
Bob.
Bob
can
send
this
to
Alice.
So
basically,
when
Bob
sent
send
this
offer
to
buy
it's
already
intending
to
is
already
intending
to
buy.
A
A
Yeah
so,
basically
I'm
a
land
line
of
thinking
of
not
encoding
the
action
to
the
to
the
cessation
I
think
this
makes
less
sense
if
we,
if,
unless
we
put
into
business
context,
I
just
hope
that
the
bear
is
in
the
business
contact
to
suddenly
show
up
and
say
hey,
we
actually
needed
the
reactions
that
can
be
done
with
this
token
pre-selected
in
URI.
Oh.
A
Yeah
yeah,
basically,
that's
it
so
I'm,
not
sure
if
I
should
show
the
encode
action
into
the
URL
or
should
encode
the
action
into
the
message.
Well,
a
certain
is
with
a
station
that
is
more
complicated
than
just
a
key
value
pair.
The
relative
distinguished
name
is
used
instead.
So
if
you
look
at
the
section
3
you
can
see,
there
is
a
academic
transcript.
A
A
A
Versus
slash
after
this
marc-andre
address,
yes,
RP,
z,
YT,
so
that's
the
encode
base64-encoded
attestation
itself,
which
is
the
entire
test
station
and
then
followed
by
question.
Mark
ei
equals
to
2020,
which
is
the
relative,
distinguished
name
of
that
and
attestation.
So
relatively
distinguished
name
is
a
set
as
one
or
several
key
value
pair
selected
from
the
gas
station
to
represent
it
like
a
name.
A
A
From
for
me,
my
my
my
attestation,
attestation
of
my
identity,
is
common
name
equal
to
wage,
an
followed
by
ID
equal
to
something
because,
unlike
companies,
common
people
have
can
have
them,
there
might
be
to
keep
two
people
named
have
say
having
the
same
name.
Therefore,
the
rDNA.
It
has
two
key
value
pairs,
not
one,
and
it's
specified
in
the
schema.
C
A
Yep,
okay,
so
that's
so
that's
the
the
only
problem
and
we
cannot
avoid
it.
We
cannot
not
encode
a
way
to
represent
a
public
key
because
otherwise,
actually
we
can
okay.
Actually
we
can
here
is
a
deal
born
I.
Have
this
talk
I?
Have
this
idea?
Do
you
think
it
will
work?
So
we
simply
don't
encode
it.
You
know.
The
public
key
is
part
of
the
test
ation
in
the
in-memory
representation
right.
A
A
C
A
A
What
you
know
Vicki
that
Ecstatic
has
to
do
value
V,
because
in
with
Alex
schema,
everything
that
is
being
signed.
The
signed
message
itself
does
not
contain
the
public
key.
Well,
if
you
use,
if
you
use
an
x.509
on
our
attestation
schema
because
the
signed
message
contains
public
key,
it's
possible
to
to
figure
out
which
public
key
is
the
right.
One.