zcash-grant-system/backend/grant/proposal/models.py

import datetime
from functools import reduce
from sqlalchemy import func, or_
from sqlalchemy.ext.hybrid import hybrid_property
from decimal import Decimal
from marshmallow import post_dump

from grant.comment.models import Comment
from grant.email.send import send_email, EmailSender
from grant.extensions import ma, db
from grant.utils.exceptions import ValidationException
from grant.utils.misc import dt_to_unix, make_url, gen_random_id
from grant.utils.requests import blockchain_get
from grant.settings import PROPOSAL_STAKING_AMOUNT
from grant.utils.enums import (
    ProposalStatus,
    ProposalStage,
    Category,
    ContributionStatus,
    ProposalArbiterStatus,
    MilestoneStage
)
from grant.utils.stubs import anonymous_user
from grant.task.jobs import ContributionExpired

proposal_team = db.Table(
    'proposal_team', db.Model.metadata,
    db.Column('user_id', db.Integer, db.ForeignKey('user.id')),
    db.Column('proposal_id', db.Integer, db.ForeignKey('proposal.id'))
)


class ProposalTeamInvite(db.Model):
    __tablename__ = "proposal_team_invite"

    id = db.Column(db.Integer(), primary_key=True)
    date_created = db.Column(db.DateTime)

    proposal_id = db.Column(db.Integer, db.ForeignKey("proposal.id"), nullable=False)
    address = db.Column(db.String(255), nullable=False)
    accepted = db.Column(db.Boolean)

    def __init__(self, proposal_id: int, address: str, accepted: bool = None):
        self.proposal_id = proposal_id
        self.address = address
        self.accepted = accepted
        self.date_created = datetime.datetime.now()

    @staticmethod
    def get_pending_for_user(user):
        return ProposalTeamInvite.query.filter(
            ProposalTeamInvite.accepted == None,
            (func.lower(user.email_address) == func.lower(ProposalTeamInvite.address))
        ).all()


class ProposalUpdate(db.Model):
    __tablename__ = "proposal_update"

    id = db.Column(db.Integer(), primary_key=True)
    date_created = db.Column(db.DateTime)

    proposal_id = db.Column(db.Integer, db.ForeignKey("proposal.id"), nullable=False)
    title = db.Column(db.String(255), nullable=False)
    content = db.Column(db.Text, nullable=False)

    def __init__(self, proposal_id: int, title: str, content: str):
        self.id = gen_random_id(ProposalUpdate)
        self.proposal_id = proposal_id
        self.title = title
        self.content = content
        self.date_created = datetime.datetime.now()


class ProposalContribution(db.Model):
    __tablename__ = "proposal_contribution"

    id = db.Column(db.Integer(), primary_key=True)
    date_created = db.Column(db.DateTime, nullable=False)

    proposal_id = db.Column(db.Integer, db.ForeignKey("proposal.id"), nullable=False)
    user_id = db.Column(db.Integer, db.ForeignKey("user.id"), nullable=True)
    status = db.Column(db.String(255), nullable=False)
    amount = db.Column(db.String(255), nullable=False)
    tx_id = db.Column(db.String(255), nullable=True)
    refund_tx_id = db.Column(db.String(255), nullable=True)
    staking = db.Column(db.Boolean, nullable=False)
    no_refund = db.Column(db.Boolean, nullable=False)

    user = db.relationship("User")

    def __init__(
            self,
            proposal_id: int,
            amount: str,
            user_id: int = None,
            staking: bool = False,
            no_refund: bool = False,
    ):
        self.proposal_id = proposal_id
        self.amount = amount
        self.user_id = user_id
        self.staking = staking
        self.no_refund = no_refund
        self.date_created = datetime.datetime.now()
        self.status = ContributionStatus.PENDING

    @staticmethod
    def get_existing_contribution(user_id: int, proposal_id: int, amount: str, no_refund: bool = False):
        return ProposalContribution.query.filter_by(
            user_id=user_id,
            proposal_id=proposal_id,
            amount=amount,
            no_refund=no_refund,
            status=ContributionStatus.PENDING,
        ).first()

    @staticmethod
    def get_by_userid(user_id):
        return ProposalContribution.query \
            .filter(ProposalContribution.user_id == user_id) \
            .filter(ProposalContribution.status != ContributionStatus.DELETED) \
            .filter(ProposalContribution.staking == False) \
            .order_by(ProposalContribution.date_created.desc()) \
            .all()

    @staticmethod
    def validate(contribution):
        proposal_id = contribution.get('proposal_id')
        user_id = contribution.get('user_id')
        status = contribution.get('status')
        amount = contribution.get('amount')
        tx_id = contribution.get('tx_id')

        # Proposal ID (must belong to an existing proposal)
        if proposal_id:
            proposal = Proposal.query.filter(Proposal.id == proposal_id).first()
            if not proposal:
                raise ValidationException('No proposal matching that ID')
            contribution.proposal_id = proposal_id
        else:
            raise ValidationException('Proposal ID is required')
        # User ID (must belong to an existing user)
        if user_id:
            user = User.query.filter(User.id == user_id).first()
            if not user:
                raise ValidationException('No user matching that ID')
            contribution.user_id = user_id
        else:
            raise ValidationException('User ID is required')
        # Status (must be in list of statuses)
        if status:
            if not ContributionStatus.includes(status):
                raise ValidationException('Invalid status')
            contribution.status = status
        else:
            raise ValidationException('Status is required')
        # Amount (must be a Decimal parseable)
        if amount:
            try:
                contribution.amount = str(Decimal(amount))
            except:
                raise ValidationException('Amount must be a number')
        else:
            raise ValidationException('Amount is required')

    def confirm(self, tx_id: str, amount: str):
        self.status = ContributionStatus.CONFIRMED
        self.tx_id = tx_id
        self.amount = amount

    @hybrid_property
    def refund_address(self):
        return self.user.settings.refund_address if self.user else None


class ProposalArbiter(db.Model):
    __tablename__ = "proposal_arbiter"

    id = db.Column(db.Integer(), primary_key=True)
    proposal_id = db.Column(db.Integer, db.ForeignKey("proposal.id"), nullable=False)
    user_id = db.Column(db.Integer, db.ForeignKey("user.id"), nullable=True)
    status = db.Column(db.String(255), nullable=False)

    proposal = db.relationship("Proposal", lazy=True, back_populates="arbiter")
    user = db.relationship("User", uselist=False, lazy=True, back_populates="arbiter_proposals")

    def __init__(self, proposal_id: int, user_id: int = None, status: str = ProposalArbiterStatus.MISSING):
        self.id = gen_random_id(ProposalArbiter)
        self.proposal_id = proposal_id
        self.user_id = user_id
        self.status = status

    def accept_nomination(self, user_id: int):
        if self.user_id == user_id:
            self.status = ProposalArbiterStatus.ACCEPTED
            db.session.add(self)
            db.session.commit()
            return
        raise ValidationException('User not nominated for arbiter')

    def reject_nomination(self, user_id: int):
        if self.user_id == user_id:
            self.status = ProposalArbiterStatus.MISSING
            self.user = None
            db.session.add(self)
            db.session.commit()
            return
        raise ValidationException('User is not arbiter')


class Proposal(db.Model):
    __tablename__ = "proposal"

    id = db.Column(db.Integer(), primary_key=True)
    date_created = db.Column(db.DateTime)
    rfp_id = db.Column(db.Integer(), db.ForeignKey('rfp.id'), nullable=True)

    # Content info
    status = db.Column(db.String(255), nullable=False)
    title = db.Column(db.String(255), nullable=False)
    brief = db.Column(db.String(255), nullable=False)
    stage = db.Column(db.String(255), nullable=False)
    content = db.Column(db.Text, nullable=False)
    category = db.Column(db.String(255), nullable=False)
    date_approved = db.Column(db.DateTime)
    date_published = db.Column(db.DateTime)
    reject_reason = db.Column(db.String())

    # Payment info
    target = db.Column(db.String(255), nullable=False)
    payout_address = db.Column(db.String(255), nullable=False)
    deadline_duration = db.Column(db.Integer(), nullable=False)
    contribution_matching = db.Column(db.Float(), nullable=False, default=0, server_default=db.text("0"))
    contribution_bounty = db.Column(db.String(255), nullable=False, default='0', server_default=db.text("'0'"))
    rfp_opt_in = db.Column(db.Boolean(), nullable=True)
    contributed = db.column_property()

    # Relations
    team = db.relationship("User", secondary=proposal_team)
    comments = db.relationship(Comment, backref="proposal", lazy=True, cascade="all, delete-orphan")
    updates = db.relationship(ProposalUpdate, backref="proposal", lazy=True, cascade="all, delete-orphan")
    contributions = db.relationship(ProposalContribution, backref="proposal", lazy=True, cascade="all, delete-orphan")
    milestones = db.relationship("Milestone", backref="proposal",
                                 order_by="asc(Milestone.index)", lazy=True, cascade="all, delete-orphan")
    invites = db.relationship(ProposalTeamInvite, backref="proposal", lazy=True, cascade="all, delete-orphan")
    arbiter = db.relationship(ProposalArbiter, uselist=False, back_populates="proposal", cascade="all, delete-orphan")

    def __init__(
            self,
            status: str = ProposalStatus.DRAFT,
            title: str = '',
            brief: str = '',
            content: str = '',
            stage: str = ProposalStage.PREVIEW,
            target: str = '0',
            payout_address: str = '',
            deadline_duration: int = 5184000,  # 60 days
            category: str = ''
    ):
        self.id = gen_random_id(Proposal)
        self.date_created = datetime.datetime.now()
        self.status = status
        self.title = title
        self.brief = brief
        self.content = content
        self.category = category
        self.target = target
        self.payout_address = payout_address
        self.deadline_duration = deadline_duration
        self.stage = stage

    @staticmethod
    def validate(proposal):
        title = proposal.get('title')
        stage = proposal.get('stage')
        category = proposal.get('category')
        if title and len(title) > 60:
            raise ValidationException("Proposal title cannot be longer than 60 characters")
        if stage and not ProposalStage.includes(stage):
            raise ValidationException("Proposal stage {} is not a valid stage".format(stage))
        if category and not Category.includes(category):
            raise ValidationException("Category {} not a valid category".format(category))

    def validate_publishable(self):
        # Require certain fields
        required_fields = ['title', 'content', 'brief', 'category', 'target', 'payout_address']
        for field in required_fields:
            if not hasattr(self, field):
                raise ValidationException("Proposal must have a {}".format(field))

        # Check with node that the address is kosher
        try:
            res = blockchain_get('/validate/address', {'address': self.payout_address})
        except:
            raise ValidationException(
                "Could not validate your payout address due to an internal server error, please try again later")
        if not res['valid']:
            raise ValidationException("Payout address is not a valid Zcash address")

        # Then run through regular validation
        Proposal.validate(vars(self))

    @staticmethod
    def create(**kwargs):
        Proposal.validate(kwargs)
        proposal = Proposal(
            **kwargs
        )

        # arbiter needs proposal.id
        db.session.add(proposal)
        db.session.flush()

        arbiter = ProposalArbiter(proposal_id=proposal.id)
        db.session.add(arbiter)

        return proposal

    @staticmethod
    def get_by_user(user, statuses=[ProposalStatus.LIVE]):
        status_filter = or_(Proposal.status == v for v in statuses)
        return Proposal.query \
            .join(proposal_team) \
            .filter(proposal_team.c.user_id == user.id) \
            .filter(status_filter) \
            .all()

    @staticmethod
    def get_by_user_contribution(user):
        return Proposal.query \
            .join(ProposalContribution) \
            .filter(ProposalContribution.user_id == user.id) \
            .order_by(ProposalContribution.date_created.desc()) \
            .all()

    def update(
            self,
            title: str = '',
            brief: str = '',
            category: str = '',
            content: str = '',
            target: str = '0',
            payout_address: str = '',
            deadline_duration: int = 5184000  # 60 days
    ):
        self.title = title
        self.brief = brief
        self.category = category
        self.content = content
        self.target = target
        self.payout_address = payout_address
        self.deadline_duration = deadline_duration
        Proposal.validate(vars(self))

    def update_rfp_opt_in(self, opt_in: bool):
        self.rfp_opt_in = opt_in
        # add/remove matching and/or bounty values from RFP
        if opt_in and self.rfp:
            self.set_contribution_matching(1 if self.rfp.matching else 0)
            self.set_contribution_bounty(self.rfp.bounty or '0')
        else:
            self.set_contribution_matching(0)
            self.set_contribution_bounty('0')

    def create_contribution(
        self,
        amount,
        user_id: int = None,
        staking: bool = False,
        no_refund: bool = False,
    ):
        contribution = ProposalContribution(
            proposal_id=self.id,
            amount=amount,
            user_id=user_id,
            staking=staking,
            no_refund=no_refund,
        )
        db.session.add(contribution)
        db.session.flush()
        if user_id:
            task = ContributionExpired(contribution)
            task.make_task()
        db.session.commit()
        return contribution

    def get_staking_contribution(self, user_id: int):
        contribution = None
        remaining = PROPOSAL_STAKING_AMOUNT - Decimal(self.amount_staked)
        # check funding
        if remaining > 0:
            # find pending contribution for any user of remaining amount
            contribution = ProposalContribution.query.filter_by(
                proposal_id=self.id,
                status=ProposalStatus.PENDING,
                staking=True,
            ).first()
            if not contribution:
                contribution = self.create_contribution(
                    user_id=user_id,
                    amount=str(remaining.normalize()),
                    staking=True,
                )

        return contribution

    # state: status (DRAFT || REJECTED) -> (PENDING || STAKING)
    def submit_for_approval(self):
        self.validate_publishable()
        allowed_statuses = [ProposalStatus.DRAFT, ProposalStatus.REJECTED]
        # specific validation
        if self.status not in allowed_statuses:
            raise ValidationException(f"Proposal status must be draft or rejected to submit for approval")
        # set to PENDING if staked, else STAKING
        if self.is_staked:
            self.status = ProposalStatus.PENDING
        else:
            self.status = ProposalStatus.STAKING

    def set_pending_when_ready(self):
        if self.status == ProposalStatus.STAKING and self.is_staked:
            self.set_pending()

    # state: status STAKING -> PENDING
    def set_pending(self):
        if self.status != ProposalStatus.STAKING:
            raise ValidationException(f"Proposal status must be staking in order to be set to pending")
        if not self.is_staked:
            raise ValidationException(f"Proposal is not fully staked, cannot set to pending")
        self.status = ProposalStatus.PENDING
        db.session.add(self)
        db.session.flush()

    # state: status PENDING -> (APPROVED || REJECTED)
    def approve_pending(self, is_approve, reject_reason=None):
        self.validate_publishable()
        # specific validation
        if not self.status == ProposalStatus.PENDING:
            raise ValidationException(f"Proposal must be pending to approve or reject")

        if is_approve:
            self.status = ProposalStatus.APPROVED
            self.date_approved = datetime.datetime.now()
            for t in self.team:
                send_email(t.email_address, 'proposal_approved', {
                    'user': t,
                    'proposal': self,
                    'proposal_url': make_url(f'/proposals/{self.id}'),
                    'admin_note': 'Congratulations! Your proposal has been approved.'
                })
        else:
            if not reject_reason:
                raise ValidationException("Please provide a reason for rejecting the proposal")
            self.status = ProposalStatus.REJECTED
            self.reject_reason = reject_reason
            for t in self.team:
                send_email(t.email_address, 'proposal_rejected', {
                    'user': t,
                    'proposal': self,
                    'proposal_url': make_url(f'/proposals/{self.id}'),
                    'admin_note': reject_reason
                })

    # state: status APPROVE -> LIVE, stage PREVIEW -> FUNDING_REQUIRED
    def publish(self):
        self.validate_publishable()
        # specific validation
        if not self.status == ProposalStatus.APPROVED:
            raise ValidationException(f"Proposal status must be approved")
        self.date_published = datetime.datetime.now()
        self.status = ProposalStatus.LIVE
        self.stage = ProposalStage.FUNDING_REQUIRED
        # If we had a bounty that pushed us into funding, skip straight into WIP
        self.set_funded_when_ready()

    def set_funded_when_ready(self):
        if self.status == ProposalStatus.LIVE and self.stage == ProposalStage.FUNDING_REQUIRED and self.is_funded:
            self.set_funded()

    # state: stage FUNDING_REQUIRED -> WIP
    def set_funded(self):
        if self.status != ProposalStatus.LIVE:
            raise ValidationException(f"Proposal status must be live in order transition to funded state")
        if self.stage != ProposalStage.FUNDING_REQUIRED:
            raise ValidationException(f"Proposal stage must be funding_required in order transition to funded state")
        if not self.is_funded:
            raise ValidationException(f"Proposal is not fully funded, cannot set to funded state")
        self.stage = ProposalStage.WIP
        db.session.add(self)
        db.session.flush()
        # check the first step, if immediate payout bump it to accepted
        self.current_milestone.accept_immediate()

    def set_contribution_bounty(self, bounty: str):
        # do not allow changes on funded/WIP proposals
        if self.is_funded:
            raise ValidationException("Cannot change contribution bounty on fully-funded proposal")
        # wrap in Decimal so it throws for non-decimal strings
        self.contribution_bounty = str(Decimal(bounty))
        db.session.add(self)
        db.session.flush()
        self.set_funded_when_ready()

    def set_contribution_matching(self, matching: float):
        # do not allow on funded/WIP proposals
        if self.is_funded:
            raise ValidationException("Cannot set contribution matching on fully-funded proposal")
        # enforce 1 or 0 for now
        if matching == 0.0 or matching == 1.0:
            self.contribution_matching = matching
            db.session.add(self)
            db.session.flush()
            self.set_funded_when_ready()
        else:
            raise ValidationException("Bad value for contribution_matching, must be 1 or 0")

    def cancel(self):
        if self.status != ProposalStatus.LIVE:
            raise ValidationException("Cannot cancel a proposal until it's live")

        self.stage = ProposalStage.CANCELED
        db.session.add(self)
        db.session.flush()

        # Send emails to team & contributors
        email_sender = EmailSender()
        for u in self.team:
            email_sender.add(u.email_address, 'proposal_canceled', {
                'proposal': self,
                'support_url': make_url('/contact'),
            })
        for c in self.contributions:
            if c.user:
                email_sender.add(c.user.email_address, 'contribution_proposal_canceled', {
                    'contribution': c,
                    'proposal': self,
                    'refund_address': c.user.settings.refund_address,
                    'account_settings_url': make_url('/profile/settings?tab=account')
                })
        email_sender.start()

    @hybrid_property
    def contributed(self):
        contributions = ProposalContribution.query \
            .filter_by(proposal_id=self.id, status=ContributionStatus.CONFIRMED, staking=False) \
            .all()
        funded = reduce(lambda prev, c: prev + Decimal(c.amount), contributions, 0)
        return str(funded)

    @hybrid_property
    def amount_staked(self):
        contributions = ProposalContribution.query \
            .filter_by(proposal_id=self.id, status=ContributionStatus.CONFIRMED, staking=True) \
            .all()
        amount = reduce(lambda prev, c: prev + Decimal(c.amount), contributions, 0)
        return str(amount)

    @hybrid_property
    def funded(self):
        target = Decimal(self.target)
        # apply matching multiplier
        funded = Decimal(self.contributed) * Decimal(1 + self.contribution_matching)
        # apply bounty
        if self.contribution_bounty:
            funded = funded + Decimal(self.contribution_bounty)
        # if funded > target, just set as target
        if funded > target:
            return str(target)

        return str(funded)

    @hybrid_property
    def is_staked(self):
        # Don't use self.contributed since that ignores stake contributions
        contributions = ProposalContribution.query \
            .filter_by(proposal_id=self.id, status=ContributionStatus.CONFIRMED) \
            .all()
        funded = reduce(lambda prev, c: prev + Decimal(c.amount), contributions, 0)
        return Decimal(funded) >= PROPOSAL_STAKING_AMOUNT

    @hybrid_property
    def is_funded(self):
        return self.is_staked and Decimal(self.funded) >= Decimal(self.target)

    @hybrid_property
    def is_failed(self):
        if not self.status == ProposalStatus.LIVE or not self.date_published:
            return False
        if self.stage == ProposalStage.FAILED or self.stage == ProposalStage.CANCELED:
            return True
        deadline = self.date_published + datetime.timedelta(seconds=self.deadline_duration)
        passed = deadline < datetime.datetime.now()
        return passed and not self.is_funded

    @hybrid_property
    def current_milestone(self):
        if self.milestones:
            for ms in self.milestones:
                if ms.stage != MilestoneStage.PAID:
                    return ms
            return self.milestones[-1]  # return last one if all PAID
        return None


class ProposalSchema(ma.Schema):
    class Meta:
        model = Proposal
        # Fields to expose
        fields = (
            "stage",
            "status",
            "date_created",
            "date_approved",
            "date_published",
            "reject_reason",
            "title",
            "brief",
            "proposal_id",
            "target",
            "contributed",
            "is_staked",
            "is_failed",
            "funded",
            "content",
            "updates",
            "milestones",
            "current_milestone",
            "category",
            "team",
            "payout_address",
            "deadline_duration",
            "contribution_matching",
            "contribution_bounty",
            "invites",
            "rfp",
            "rfp_opt_in",
            "arbiter"
        )

    date_created = ma.Method("get_date_created")
    date_approved = ma.Method("get_date_approved")
    date_published = ma.Method("get_date_published")
    proposal_id = ma.Method("get_proposal_id")

    updates = ma.Nested("ProposalUpdateSchema", many=True)
    team = ma.Nested("UserSchema", many=True)
    milestones = ma.Nested("MilestoneSchema", many=True)
    current_milestone = ma.Nested("MilestoneSchema")
    invites = ma.Nested("ProposalTeamInviteSchema", many=True)
    rfp = ma.Nested("RFPSchema", exclude=["accepted_proposals"])
    arbiter = ma.Nested("ProposalArbiterSchema", exclude=["proposal"])

    def get_proposal_id(self, obj):
        return obj.id

    def get_date_created(self, obj):
        return dt_to_unix(obj.date_created)

    def get_date_approved(self, obj):
        return dt_to_unix(obj.date_approved) if obj.date_approved else None

    def get_date_published(self, obj):
        return dt_to_unix(obj.date_published) if obj.date_published else None


proposal_schema = ProposalSchema()
proposals_schema = ProposalSchema(many=True)
user_fields = [
    "proposal_id",
    "status",
    "title",
    "brief",
    "target",
    "is_staked",
    "funded",
    "contribution_matching",
    "date_created",
    "date_approved",
    "date_published",
    "reject_reason",
    "team",
]
user_proposal_schema = ProposalSchema(only=user_fields)
user_proposals_schema = ProposalSchema(many=True, only=user_fields)


class ProposalUpdateSchema(ma.Schema):
    class Meta:
        model = ProposalUpdate
        # Fields to expose
        fields = (
            "update_id",
            "date_created",
            "proposal_id",
            "title",
            "content"
        )

    date_created = ma.Method("get_date_created")
    proposal_id = ma.Method("get_proposal_id")
    update_id = ma.Method("get_update_id")

    def get_update_id(self, obj):
        return obj.id

    def get_proposal_id(self, obj):
        return obj.proposal_id

    def get_date_created(self, obj):
        return dt_to_unix(obj.date_created)


proposal_update_schema = ProposalUpdateSchema()
proposals_update_schema = ProposalUpdateSchema(many=True)


class ProposalTeamInviteSchema(ma.Schema):
    class Meta:
        model = ProposalTeamInvite
        fields = (
            "id",
            "date_created",
            "address",
            "accepted"
        )

    date_created = ma.Method("get_date_created")

    def get_date_created(self, obj):
        return dt_to_unix(obj.date_created)


proposal_team_invite_schema = ProposalTeamInviteSchema()
proposal_team_invites_schema = ProposalTeamInviteSchema(many=True)


class InviteWithProposalSchema(ma.Schema):
    class Meta:
        model = ProposalTeamInvite
        fields = (
            "id",
            "date_created",
            "address",
            "accepted",
            "proposal"
        )

    date_created = ma.Method("get_date_created")
    proposal = ma.Nested("ProposalSchema")

    def get_date_created(self, obj):
        return dt_to_unix(obj.date_created)


invite_with_proposal_schema = InviteWithProposalSchema()
invites_with_proposal_schema = InviteWithProposalSchema(many=True)


class ProposalContributionSchema(ma.Schema):
    class Meta:
        model = ProposalContribution
        # Fields to expose
        fields = (
            "id",
            "proposal",
            "user",
            "status",
            "tx_id",
            "amount",
            "date_created",
            "addresses",
            "is_anonymous",
        )

    proposal = ma.Nested("ProposalSchema")
    user = ma.Nested("UserSchema", default=anonymous_user)
    date_created = ma.Method("get_date_created")
    addresses = ma.Method("get_addresses")
    is_anonymous = ma.Method("get_is_anonymous")

    def get_date_created(self, obj):
        return dt_to_unix(obj.date_created)

    def get_addresses(self, obj):
        # Omit 'memo' and 'sprout' for now
        # NOTE: Add back in 'sapling' when ready
        addresses = blockchain_get('/contribution/addresses', {'contributionId': obj.id})
        return {
            'transparent': addresses['transparent'],
        }

    def get_is_anonymous(self, obj):
        return not obj.user_id

    @post_dump
    def stub_anonymous_user(self, data):
        if 'user' in data and data['user'] is None:
            data['user'] = anonymous_user
        return data


proposal_contribution_schema = ProposalContributionSchema()
proposal_contributions_schema = ProposalContributionSchema(many=True)
user_proposal_contribution_schema = ProposalContributionSchema(exclude=['user', 'addresses'])
user_proposal_contributions_schema = ProposalContributionSchema(many=True, exclude=['user', 'addresses'])
proposal_proposal_contribution_schema = ProposalContributionSchema(exclude=['proposal', 'addresses'])
proposal_proposal_contributions_schema = ProposalContributionSchema(many=True, exclude=['proposal', 'addresses'])


class AdminProposalContributionSchema(ma.Schema):
    class Meta:
        model = ProposalContribution
        # Fields to expose
        fields = (
            "id",
            "proposal",
            "user",
            "status",
            "tx_id",
            "amount",
            "date_created",
            "addresses",
            "refund_address",
            "refund_tx_id",
            "staking",
            "no_refund",
        )

    proposal = ma.Nested("ProposalSchema")
    user = ma.Nested("UserSchema")
    date_created = ma.Method("get_date_created")
    addresses = ma.Method("get_addresses")

    def get_date_created(self, obj):
        return dt_to_unix(obj.date_created)

    def get_addresses(self, obj):
        return blockchain_get('/contribution/addresses', {'contributionId': obj.id})


admin_proposal_contribution_schema = AdminProposalContributionSchema()
admin_proposal_contributions_schema = AdminProposalContributionSchema(many=True)


class ProposalArbiterSchema(ma.Schema):
    class Meta:
        model = ProposalArbiter
        fields = (
            "id",
            "user",
            "proposal",
            "status"
        )

    user = ma.Nested("UserSchema")  # , exclude=['arbiter_proposals'] (if UserSchema ever includes it)
    proposal = ma.Nested("ProposalSchema", exclude=['arbiter'])


user_proposal_arbiter_schema = ProposalArbiterSchema(exclude=['user'])
user_proposal_arbiters_schema = ProposalArbiterSchema(many=True, exclude=['user'])