feat: add Decision column to TUVote

In preparation for allowing TUs to change their votes on proposals,
we need a way to track what users vote for.

Without this, the vote decisions are stored within the related
TU_VoteInfo record, decoupled from the user who made the vote.

That being the case meant we cannot actually change a vote, because
we can't figure out what TU_VoteInfo decision columns to decrement
when the vote has changed.

You may be wondering why we aren't removing the decision columns out
of TU_VoteInfo with the advent of this new column. The reason being:
previous votes are all calculated off of the TU_VoteInfo columns, so
without a manual DB rework, relocating them to the user-related vote
records would break outcomes of old proposals. So, the plan is:
we'll solely use this column for votes from this point on to track
what decision a user made internally, which will open up TUs changing
their decision.

In addition, this migration resets all running proposals:
- all votes are deleted
- time is reset to Start when migration is run

This was necessary to put running proposals into a state that can
take advantage of the new revote system.

Signed-off-by: Kevin Morris <kevr@0cost.org>

aurweb/models/tu_vote.py

@@ -6,6 +6,17 @@ from aurweb.models.declarative import Base
 from aurweb.models.tu_voteinfo import TUVoteInfo as _TUVoteInfo
 from aurweb.models.user import User as _User
 
+YES_ID = 1
+NO_ID = 2
+ABSTAIN_ID = 3
+
+DECISIONS = {
+    YES_ID: "Yes",
+    NO_ID: "No",
+    ABSTAIN_ID: "Abstain",
+}
+DECISION_IDS = {v: k for k, v in DECISIONS.items()}
+
 
 class TUVote(Base):
     __table__ = schema.TU_Votes
@@ -29,10 +40,17 @@ class TUVote(Base):
             raise IntegrityError(
                 statement="Foreign key VoteID cannot be null.",
                 orig="TU_Votes.VoteID",
-                params=("NULL"))
+                params=("NULL",))
 
         if not self.User and not self.UserID:
             raise IntegrityError(
                 statement="Foreign key UserID cannot be null.",
                 orig="TU_Votes.UserID",
-                params=("NULL"))
+                params=("NULL",))
+
+        if self.Decision is None or self.Decision not in DECISIONS:
+            raise IntegrityError(
+                statement=("Decision column must be a valid key in "
+                           "aurweb.models.tu_vote.DECISIONS"),
+                orig="TU_Votes.Decision",
+                params=(self.Decision,))

aurweb/schema.py

@@ -406,6 +406,7 @@ TU_Votes = Table(
     'TU_Votes', metadata,
     Column('VoteID', ForeignKey('TU_VoteInfo.ID', ondelete='CASCADE'), nullable=False),
     Column('UserID', ForeignKey('Users.ID', ondelete='CASCADE'), nullable=False),
+    Column('Decision', TINYINT(unsigned=True)),
     mysql_engine='InnoDB',
 )
 

migrations/versions/84cd90073dde_relocate_vote_decisions_into_tuvote.py

@@ -0,0 +1,61 @@
+"""relocate vote decisions into TUVote
+
+Revision ID: 84cd90073dde
+Revises: d64e5571bc8d
+Create Date: 2022-03-07 18:02:28.791103
+
+This migration allows us to give Trusted Users the ability to
+modify a vote they made on a proposal. Previously, the decision
+was tracked purely through TU_VoteInfo records, which removes
+tracking of what decisions users made. This blocks us from being
+able to modify votes, because we can't update the TU_VoteInfo
+Yes, No or Abstain columns properly.
+
+"""
+import sqlalchemy as sa
+
+from alembic import op
+from sqlalchemy.dialects.mysql import TINYINT
+
+from aurweb import db, logging, time
+from aurweb.models import TUVoteInfo
+
+logger = logging.get_logger("alembic")
+
+# revision identifiers, used by Alembic.
+revision = '84cd90073dde'
+down_revision = 'd64e5571bc8d'
+branch_labels = None
+depends_on = None
+
+TABLE = "TU_Votes"
+
+
+def upgrade():
+    decision = sa.Column("Decision", TINYINT(unsigned=True))
+    op.add_column(TABLE, decision)
+
+    # For each proposal which is running at the time this migration
+    # is applied, eradicate all related votes. We will restart the votes.
+    # In addition, reset the Submitted and End columns based on the current
+    # timestamp; essentially resetting the proposal's state.
+    utcnow = time.utcnow()
+    running_proposals = db.query(TUVoteInfo).filter(TUVoteInfo.End > utcnow)
+    with db.begin():
+        for proposal in running_proposals:
+            logger.info(f"Resetting proposal with ID {proposal.ID}: "
+                        "Yes = 0, No = 0, Abstain = 0, deleted vote records")
+
+            # Reset the Submitted and End columns.
+            length = proposal.End - proposal.Submitted
+            proposal.Submitted = utcnow
+            proposal.End = utcnow + length
+
+            proposal.Yes = proposal.No = proposal.Abstain = 0
+            db.delete_all(proposal.tu_votes)
+            logger.info(f"Proposal time range was reset: Submitted = "
+                        f"{proposal.Submitted} and End = {proposal.End}")
+
+
+def downgrade():
+    op.drop_column(TABLE, "Decision")

test/test_tu_vote.py

@@ -4,7 +4,7 @@ from sqlalchemy.exc import IntegrityError
 
 from aurweb import db, time
 from aurweb.models.account_type import TRUSTED_USER_ID
-from aurweb.models.tu_vote import TUVote
+from aurweb.models.tu_vote import YES_ID, TUVote
 from aurweb.models.tu_voteinfo import TUVoteInfo
 from aurweb.models.user import User
 
@@ -36,10 +36,12 @@ def tu_voteinfo(user: User) -> TUVoteInfo:
 
 def test_tu_vote_creation(user: User, tu_voteinfo: TUVoteInfo):
     with db.begin():
-        tu_vote = db.create(TUVote, User=user, VoteInfo=tu_voteinfo)
+        tu_vote = db.create(TUVote, User=user, VoteInfo=tu_voteinfo,
+                            Decision=YES_ID)
 
     assert tu_vote.VoteInfo == tu_voteinfo
     assert tu_vote.User == user
+    assert tu_vote.Decision == YES_ID
     assert tu_vote in user.tu_votes
     assert tu_vote in tu_voteinfo.tu_votes
 
@@ -52,3 +54,12 @@ def test_tu_vote_null_user_raises_exception(tu_voteinfo: TUVoteInfo):
 def test_tu_vote_null_voteinfo_raises_exception(user: User):
     with pytest.raises(IntegrityError):
         TUVote(User=user)
+
+
+def test_tu_vote_bad_decision_raises_exception(user: User,
+                                               tu_voteinfo: TUVoteInfo):
+    with pytest.raises(IntegrityError):
+        TUVote(User=user, VoteInfo=tu_voteinfo, Decision=None)
+
+    with pytest.raises(IntegrityError):
+        TUVote(User=user, VoteInfo=tu_voteinfo, Decision=0)