from __future__ import annotations # standard imports import base64 import json import logging import os # types from typing import TYPE_CHECKING if TYPE_CHECKING: from cic.cmd.arg import CmdCtrl # external imports from cic_types import MetadataPointer from cic_types.processor import generate_metadata_pointer from hexathon import strip_0x from cic.MetaRequestHandler import MetadataRequestsHandler from cic.output import OutputWriter from cic.utils import object_to_str # local imports from .base import Data, data_dir logg = logging.getLogger(__name__) class Meta(Data): """Serialize and publish metadata for token. The token metadata is any mutable data that is not part of the initial token proof, but published simultaneously as the token nonetheless. :param path: Path to settings directory :type path: str :param writer: Writer interface receiving the output of the processor :type writer: cic.output.OutputWriter """ def __init__( self, path=".", writer=None, name="", location="", country_code="", contact={} ): super(Meta, self).__init__() self.name = name self.contact = contact self.country_code = country_code self.location = location self.path = path self.writer = writer self.meta_path = os.path.join(self.path, "meta.json") def load(self): """Load metadata from settings.""" super(Meta, self).load() f = open(self.meta_path, "r", encoding="utf-8") o = json.load(f) f.close() self.name = o["name"] self.contact = o["contact"] self.country_code = o["country_code"] self.location = o["location"] self.inited = True def start(self): """Initialize metadata settings from template.""" super(Meta, self).start() meta_template_file_path = os.path.join( data_dir, f"meta_template_v{self.version()}.json" ) f = open(meta_template_file_path, encoding="utf-8") o = json.load(f) f.close() o["name"] = self.name o["contact"] = self.contact o["country_code"] = self.country_code o["location"] = self.location f = open(self.meta_path, "w", encoding="utf-8") json.dump(o, f, sort_keys=True, indent="\t") f.close() def reference(self, token_address): """Calculate the mutable reference for the token metadata.""" token_address_bytes = bytes.fromhex(strip_0x(token_address)) return generate_metadata_pointer( token_address_bytes, MetadataPointer.TOKEN_META ) def asdict(self): """Output proof state to dict.""" return { "name": self.name, "country_code": self.country_code, "location": self.location, "contact": self.contact, } def process(self, token_address=None, token_symbol=None, writer=None): """Serialize and publish metadata. See cic.processor.Processor.process """ if writer is None: writer = self.writer v = json.dumps(self.asdict()) token_address_bytes = bytes.fromhex(strip_0x(token_address)) k = generate_metadata_pointer(token_address_bytes, MetadataPointer.TOKEN_META) writer.write(k, v.encode("utf-8")) token_symbol_bytes = token_symbol.encode("utf-8") k = generate_metadata_pointer( token_symbol_bytes, MetadataPointer.TOKEN_META_SYMBOL ) writer.write(k, v.encode("utf-8")) return (k, v) def __str__(self): return object_to_str(self, ["name", "contact", "country_code", "location"]) class MetadataWriter(OutputWriter): """Custom writer for publishing data under immutable content-addressed pointers in the cic-meta storage backend. Data that is not utf-8 will be converted to base64 before publishing. Implements cic.output.OutputWriter """ def write(self, k, v): rq = MetadataRequestsHandler(MetadataPointer.NONE, bytes.fromhex(k)) try: v = v.decode("utf-8") v = json.loads(v) logg.debug(f"metadatawriter bindecode {k} {v}") except UnicodeDecodeError: v = base64.b64encode(v).decode("utf-8") v = json.loads(json.dumps(v)) logg.debug(f"metadatawriter b64encode {k} {v}") r = rq.create(v) logg.info(f"metadata submitted at {k}") return r