def to_comb(self) -> PairType:
return PairType.from_comb(items=[
AddressType(self.ticketer), self.item,
NatType(self.amount)
])
def compile_view_fa2_token_metadata(tokens: List[TokenMetadata]):
from pytezos.michelson.types.core import BytesType, NatType, StringType
from pytezos.michelson.types.map import MapType
from pytezos.michelson.types.pair import PairType
# this map is of type:
# map nat (nat, map string bytes)
elt = MapType.from_items([(
NatType.from_value(token.id),
PairType.from_comb([
NatType.from_value(token.id),
MapType.from_items([
(StringType.from_value(key), BytesType.from_value(value))
for key, value in sorted(token.attrs.items())
]),
]),
) for token in tokens])
# Below code takes a '(nat, state)', looks up the 'nat' from the map above ('elt'),
# and returns the result.
code = [
# get the 'fst' of the '(nat, state)' pair
{
"prim": "CAR"
},
# push the 'elt' to the stack
{
"prim": "PUSH",
"args": [elt.as_micheline_expr(),
elt.to_micheline_value()]
},
# swap the top two elements (to match 'get's parameter order)
{
"prim": "SWAP"
},
# lookup the given 'nat' from the map
{
"prim": "GET"
},
# fail if we don't get something, return otherwise
{
"prim":
"IF_NONE",
"args": [ # if none
[
{
"prim":
"PUSH",
"args": [{
"prim": "string"
}, {
"string": "FA2_UNKNOWN_TOKEN"
}],
},
{
"prim": "FAILWITH"
},
],
# if not none
[],
],
},
]
return {
"name": "token_metadata",
"code": code,
"parameter": {
"prim": "nat"
},
"returnType": {
"prim":
"pair",
"args": [
{
"prim": "nat"
},
{
"prim": "map",
"args": [{
"prim": "string"
}, {
"prim": "bytes"
}]
},
],
},
}