Data reduction: Send image url instead of image data on search

alembic/env.py

@@ -7,6 +7,7 @@
 from sqlalchemy import pool
 
 from alembic import context
+from app.orm import base
 
 # this is the Alembic Config object, which provides
 # access to the values within the .ini file in use.
@@ -20,7 +21,7 @@
 # for 'autogenerate' support
 # from myapp import mymodel
 # target_metadata = mymodel.Base.metadata
-target_metadata = None
+target_metadata = base.BaseOrm.metadata
 
 # other values from the config, defined by the needs of env.py,
 # can be acquired:

alembic/versions/1a4804acc824_add_raw_img_column_to_creatures_table.py

@@ -0,0 +1,53 @@
+"""add raw img column to creatures table
+
+Revision ID: 1a4804acc824
+Revises: 85bc789138fe
+Create Date: 2021-10-11 04:24:03.926897
+
+"""
+from alembic import op
+import sqlalchemy as sa
+from sqlalchemy.dialects import postgresql
+from sqlalchemy.sql import table, column
+from sqlalchemy import String
+from sqlalchemy.sql.expression import select
+from sqlalchemy.sql.sqltypes import Integer, LargeBinary
+
+from app.orm.creature import convert_from_base64_img_tag_data
+
+# revision identifiers, used by Alembic.
+revision = '1a4804acc824'
+down_revision = '85bc789138fe'
+branch_labels = None
+depends_on = None
+import logging
+LOG = logging.getLogger(__file__)
+
+RAW_COLUMN = 'battle_sprite_raw'
+B64_COLUMN = 'battle_sprite'
+
+def upgrade():
+    bind = op.get_bind()
+    session = sa.orm.Session(bind=bind)
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.add_column('creatures', sa.Column(RAW_COLUMN, sa.LargeBinary(), nullable=True))
+	# ### end Alembic commands ###
+    # decode base64 image back into png
+    creature = table('creatures',column('id', Integer), column(B64_COLUMN, String), column(RAW_COLUMN, LargeBinary))
+
+    results = session.execute(select(creature.c.id, creature.c.battle_sprite))
+    for (id_, data) in results:
+        png = convert_from_base64_img_tag_data(data)
+        session.execute(creature
+        .update()
+        .where(creature.c.id == id_)
+        .values(battle_sprite_raw=png,)
+        )
+
+    op.alter_column('creatures', RAW_COLUMN, nullable=False)
+
+
+
+def downgrade():
+    op.drop_column('creatures', RAW_COLUMN)
+    # ### end Alembic commands ###

alembic/versions/93edf5b21ef6_add_raw_image_column_to_klass_table.py

@@ -0,0 +1,51 @@
+"""add raw image column to klass table
+
+Revision ID: 93edf5b21ef6
+Revises: 1a4804acc824
+Create Date: 2021-10-11 21:47:09.420963
+
+"""
+from alembic import op
+import sqlalchemy as sa
+from sqlalchemy.dialects import postgresql
+from sqlalchemy.sql.expression import column, select, table
+from sqlalchemy.sql.sqltypes import Integer, LargeBinary, String
+from sqlalchemy.sql.type_api import INTEGERTYPE
+
+from app.orm.creature import convert_from_base64_img_tag_data
+
+# revision identifiers, used by Alembic.
+revision = '93edf5b21ef6'
+down_revision = '1a4804acc824'
+branch_labels = None
+depends_on = None
+
+RAW_COLUMN = 'icon_raw'
+B64_COLUMN = 'icon'
+
+def upgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.add_column('klasses', sa.Column('icon_raw', sa.LargeBinary(), nullable=True))
+    # ### end Alembic commands ###
+    bind = op.get_bind()
+    session = sa.orm.Session(bind=bind)
+
+
+    klass = table('klasses',column('id', Integer), column(B64_COLUMN, String), column(RAW_COLUMN, LargeBinary))
+
+    results = session.execute(select(klass.c.id, klass.c.icon))
+    for (id_, data) in results:
+        png = convert_from_base64_img_tag_data(data)
+        session.execute(klass
+        .update()
+        .where(klass.c.id == id_)
+        .values(icon_raw=png,)
+        )
+
+    op.alter_column('klasses', RAW_COLUMN, nullable=False)
+
+
+def downgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_column('klasses', 'icon_raw')
+    # ### end Alembic commands ###

app/models/creature.py

@@ -1,7 +1,8 @@
+from __future__ import annotations
 from datetime import datetime
 
 from typing import List, Optional
-from pydantic import BaseModel
+from pydantic import BaseModel, Field
 
 from .base import BaseModelOrm
 from .klass import KlassModel
@@ -16,7 +17,8 @@ class CreatureModel(BaseModel, BaseModelOrm):
     slug: str
     description: Optional[str] = None
 
-    battle_sprite: str
+    # url for battle sprite
+    battle_sprite_url: str = Field(None, alias="battle_sprite")
 
     health: int
     attack: int
@@ -34,3 +36,5 @@ class CreatureModel(BaseModel, BaseModelOrm):
 
     class Config:
         orm_mode = True
+        # The alias field must not ever be supplied else its contents will be used instead
+        allow_population_by_field_name = True

app/models/klass.py

@@ -2,6 +2,7 @@
 
 from typing import Optional
 from pydantic import BaseModel
+from pydantic.fields import Field
 
 from .base import BaseModelOrm
 
@@ -13,10 +14,12 @@ class KlassModel(BaseModel, BaseModelOrm):
     description: Optional[str] = None
 
     color: str
-    icon: str
+    icon_url: str = Field(None, alias="icon")
 
     created_at: datetime
     updated_at: datetime
 
     class Config:
         orm_mode = True
+        # The alias field must never be supplied else its contents will be used instead
+        allow_population_by_field_name = True

app/models/race.py

@@ -2,6 +2,7 @@
 
 from typing import Optional
 from pydantic import BaseModel
+from pydantic.fields import Field
 
 from .base import BaseModelOrm
 from .klass import KlassModel
@@ -13,11 +14,13 @@ class RaceModel(BaseModel, BaseModelOrm):
     slug: str
     description: Optional[str] = None
 
-    icon: str
+    icon_url: str = Field(None, alias="icon")
     default_klass: KlassModel
 
     created_at: datetime
     updated_at: datetime
 
     class Config:
         orm_mode = True
+        # The alias field must not ever be supplied else its contents will be used instead
+        allow_population_by_field_name = True

app/orm/creature.py

@@ -1,10 +1,24 @@
+import base64
 from sqlalchemy import Column, Integer, String, ForeignKey, Text, TIMESTAMP
 from sqlalchemy.orm import relationship
 from sqlalchemy.ext.associationproxy import association_proxy
+from sqlalchemy.sql.sqltypes import LargeBinary
+from sqlalchemy.util.langhelpers import hybridproperty
 
 from .base import BaseOrm, build_slug_defaulter, FullText
 
 
+def default_img_data(context) -> bytes:
+    b64 = context.get_current_parameters()["battle_sprite"]
+    return convert_from_base64_img_tag_data(b64)
+
+
+def convert_from_base64_img_tag_data(b64: str) -> bytes:
+    # get the base64 data only, chop off web type info
+    data = b64.split("data:image/png;base64,")[1]
+    return base64.b64decode(data)
+
+
 class CreatureOrm(BaseOrm):
     __tablename__ = "creatures"
 
@@ -21,7 +35,15 @@ class CreatureOrm(BaseOrm):
     )
     description = Column(Text())
 
-    battle_sprite = Column(Text(), nullable=False)
+    battle_sprite_base64 = Column("battle_sprite", Text(), nullable=False)
+    battle_sprite_raw = Column(
+        LargeBinary, nullable=False, default=default_img_data
+    )
+
+    @hybridproperty
+    def battle_sprite_url(self):
+        val = f"/api/creatures/{self.id}/images/battle_sprite.png"
+        return val
 
     health = Column("health", Integer, nullable=False)
     attack = Column("attack", Integer, nullable=False)

app/orm/klass.py

@@ -1,8 +1,16 @@
 from sqlalchemy import Column, Integer, String, Text, TIMESTAMP
+from sqlalchemy.sql.sqltypes import LargeBinary
+from sqlalchemy.util.langhelpers import hybridproperty
 
+from app.orm.creature import convert_from_base64_img_tag_data
 from .base import BaseOrm, build_slug_defaulter, FullText
 
 
+def default_img_data(context) -> bytes:
+    b64 = context.get_current_parameters()["icon"]
+    return convert_from_base64_img_tag_data(b64)
+
+
 class KlassOrm(BaseOrm):
     __tablename__ = "klasses"
 
@@ -20,7 +28,15 @@ class KlassOrm(BaseOrm):
     description = Column(Text())
 
     color = Column(String(10), nullable=False)
-    icon = Column(Text(), nullable=False)
+    icon_b64 = Column("icon", Text(), nullable=False)
+    icon_raw = Column(
+        "icon_raw", LargeBinary, nullable=False, default=default_img_data
+    )
+
+    @hybridproperty
+    def icon_url(self):
+        val = f"/api/classes/{self.id}/images/icon.png"
+        return val
 
     created_at = Column("created_at", TIMESTAMP, nullable=False)
     updated_at = Column("updated_at", TIMESTAMP, nullable=False)

app/orm/race.py

@@ -1,8 +1,16 @@
 from sqlalchemy import Column, Integer, String, Text, ForeignKey, TIMESTAMP
 from sqlalchemy.orm import relationship
 from sqlalchemy.ext.associationproxy import association_proxy
+from sqlalchemy.sql.sqltypes import LargeBinary
+from sqlalchemy.util.langhelpers import hybridproperty
 
 from .base import BaseOrm, build_slug_defaulter, FullText
+from app.orm.creature import convert_from_base64_img_tag_data
+
+
+def default_img_data(context) -> bytes:
+    b64 = context.get_current_parameters()["icon"]
+    return convert_from_base64_img_tag_data(b64)
 
 
 class RaceOrm(BaseOrm):
@@ -21,7 +29,15 @@ class RaceOrm(BaseOrm):
     )
     description = Column(Text())
 
-    icon = Column(Text(), nullable=False)
+    icon_b64 = Column("icon", Text(), nullable=False)
+    icon_raw = Column(
+        "icon_raw", LargeBinary, nullable=False, default=default_img_data
+    )
+
+    @hybridproperty
+    def icon_url(self):
+        val = f"/api/races/{self.id}/images/icon.png"
+        return val
 
     default_klass_id = Column(
         Integer, ForeignKey("klasses.id"), nullable=False

app/routers/classes.py

@@ -3,6 +3,7 @@
 from fastapi import APIRouter, Depends
 from pydantic import BaseModel
 from sqlalchemy import func
+from starlette.responses import Response
 
 from app.orm.klass import KlassOrm
 from app.models.klass import KlassModel
@@ -123,3 +124,25 @@ def get(klass_id: str, session=Depends(has_session)):
     )
     klasses_model = KlassModel.from_orm(klasses_orm)
     return KlassesGetSchema(data=klasses_model)
+
+
+@router.get(
+    "/{klass_id}/images/icon.png",
+    # Set what the media type will be in the autogenerated OpenAPI specification.
+    # fastapi.tiangolo.com/advanced/additional-responses/#additional-media-types-for-the-main-response
+    responses={200: {"content": {"image/png": {}}}},
+    # Prevent FastAPI from adding "application/json" as an additional
+    # response media type in the autogenerated OpenAPI specification.
+    # https://github.com/tiangolo/fastapi/issues/3258
+    response_class=Response,
+)
+def fetch_class_icon(klass_id: int, session=Depends(has_session)):
+    png = (
+        select(KlassOrm.icon_raw)
+        .where(KlassOrm.id == klass_id)
+        .get_scalar(session)
+    )
+
+    headers = {"Cache-Control": "public,max-age=604800,immutable"}
+
+    return Response(content=png, media_type="image/png", headers=headers)

app/routers/creatures.py

@@ -4,6 +4,7 @@
 from pydantic import BaseModel
 from sqlalchemy.orm import contains_eager, selectinload
 from sqlalchemy import func
+from starlette.responses import Response
 
 from app.orm.creature import CreatureOrm
 from app.models.creature import CreatureModel
@@ -113,6 +114,28 @@ class CreaturesSearchRequest(BaseModel):
     sorting: Optional[SortingRequestSchema] = SortingRequestSchema()
 
 
+@router.get(
+    "/{creature_id}/images/battle_sprite.png",
+    # Set what the media type will be in the autogenerated OpenAPI specification.
+    # fastapi.tiangolo.com/advanced/additional-responses/#additional-media-types-for-the-main-response
+    responses={200: {"content": {"image/png": {}}}},
+    # Prevent FastAPI from adding "application/json" as an additional
+    # response media type in the autogenerated OpenAPI specification.
+    # https://github.com/tiangolo/fastapi/issues/3258
+    response_class=Response,
+)
+def fetch_creature_sprite(creature_id: int, session=Depends(has_session)):
+    png = (
+        select(CreatureOrm.battle_sprite_raw)
+        .where(CreatureOrm.id == creature_id)
+        .get_scalar(session)
+    )
+
+    headers = {"Cache-Control": "public,max-age=604800,immutable"}
+
+    return Response(content=png, media_type="image/png", headers=headers)
+
+
 @router.post("/search", response_model=CreaturesSearchSchema)
 def search(search: CreaturesSearchRequest, session=Depends(has_session)):
     creatures_count = (