diff --git a/Procfile b/Procfile
new file mode 100644
index 000000000..62e430aca
--- /dev/null
+++ b/Procfile
@@ -0,0 +1 @@
+web: gunicorn 'app:create_app()'
\ No newline at end of file
diff --git a/app/__init__.py b/app/__init__.py
index 70b4cabfe..192f7086a 100644
--- a/app/__init__.py
+++ b/app/__init__.py
@@ -1,7 +1,33 @@
 from flask import Flask
+from flask_sqlalchemy import SQLAlchemy
+from flask_migrate import Migrate
+from dotenv import load_dotenv
+import os
 
+db = SQLAlchemy()
+migrate = Migrate()
+load_dotenv()
 
 def create_app(test_config=None):
     app = Flask(__name__)
+    
+    app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False
+    if not test_config:       
+        app.config['SQLALCHEMY_DATABASE_URI'] = os.environ.get('SQLALCHEMY_DATABASE_URI')
+    else:
+        app.config["Testing"] = True
+        app.config['SQLALCHEMY_TEST_DATABASE_URI'] = os.environ.get('SQLALCHEMY_TEST_DATABASE_URI')
+
+    from app.models.planet import Planet
+    from app.models.moon import Moon
+
+    db.init_app(app)
+    migrate.init_app(app, db)
+
+    from .planets_routes import planets_bp
+    app.register_blueprint(planets_bp)
+
+    from .moons_routes import moons_bp
+    app.register_blueprint(moons_bp)
 
     return app
diff --git a/app/models/__init__.py b/app/models/__init__.py
new file mode 100644
index 000000000..e69de29bb
diff --git a/app/models/moon.py b/app/models/moon.py
new file mode 100644
index 000000000..8ad88f8fb
--- /dev/null
+++ b/app/models/moon.py
@@ -0,0 +1,26 @@
+from app import db
+
+class Moon(db.Model):
+    id = db.Column(db.Integer, primary_key=True, autoincrement=True)
+    size = db.Column(db.Integer)
+    description = db.Column(db.String)
+    name = db.Column(db.String)
+    planet_id = db.Column(db.Integer, db.ForeignKey('planet.id'))
+    planets = db.relationship("Planet", back_populates = "moons")
+
+    def to_dict(self):
+        moon_dict = {}
+        moon_dict["id"] = self.id
+        moon_dict["size"] = self.size
+        moon_dict["description"] = self.description
+        moon_dict["name"] = self.name
+        return moon_dict
+
+    @classmethod
+    def from_dict(cls, moon_data):
+        new_moon = Moon(
+            name = moon_data["name"],
+            description = moon_data["description"],
+            size = moon_data["size"]
+        )
+        return new_moon
\ No newline at end of file
diff --git a/app/models/planet.py b/app/models/planet.py
new file mode 100644
index 000000000..934501251
--- /dev/null
+++ b/app/models/planet.py
@@ -0,0 +1,31 @@
+from app import db
+
+class Planet(db.Model):
+    id = db.Column(db.Integer, primary_key=True, autoincrement=True)
+    name = db.Column(db.String, nullable=False)
+    description = db.Column(db.String)
+    diameter_in_km = db.Column(db.Integer)
+    moons = db.relationship("Moon", back_populates = "planets")
+    
+
+    def to_dict(self):
+        planet_dict = {}
+        planet_dict["id"] = self.id
+        planet_dict["name"] = self.name
+        planet_dict["description"] = self.description
+        planet_dict["diameter_in_km"] = self.diameter_in_km
+        moon_names = []
+        for moon in self.moons:
+            moon_names.append(moon.name)
+        planet_dict["moons"] = moon_names
+        return planet_dict
+
+
+    @classmethod
+    def from_dict(cls, planet_data):
+        new_planet = Planet(
+            name = planet_data["name"],
+            description = planet_data["description"],
+            diameter_in_km = planet_data["diameter_in_km"]
+        )
+        return new_planet
diff --git a/app/moons_routes.py b/app/moons_routes.py
new file mode 100644
index 000000000..572f19da7
--- /dev/null
+++ b/app/moons_routes.py
@@ -0,0 +1,32 @@
+from app import db
+from app.models.planet import Planet
+from app.models.moon import Moon
+from app.planets_routes import validate_model
+from app.models.moon import Moon
+from flask import Blueprint, jsonify, abort, make_response, request
+
+moons_bp = Blueprint("moons_bp", __name__, url_prefix="/moons")
+
+@moons_bp.route("", methods=["POST"])
+def create_moon():
+    moon_data = request.get_json()
+    new_moon = Moon.from_dict(moon_data)
+    
+    db.session.add(new_moon)
+    db.session.commit()
+
+    return make_response(jsonify(f"Moon {new_moon.id} successfully created"), 201)
+
+@moons_bp.route("", methods=["GET"])
+def get_all_moons():
+    moons = Moon.query.all()
+
+    moons_response = []
+    for moon in moons:
+        moons_response.append(moon.to_dict())
+    return jsonify(moons_response)
+
+@moons_bp.route("/<moon_id>", methods=["GET"])
+def get_one_moon(moon_id):
+    moon = validate_model(Moon, moon_id)
+    return moon.to_dict()
diff --git a/app/planets_routes.py b/app/planets_routes.py
new file mode 100644
index 000000000..894a940d7
--- /dev/null
+++ b/app/planets_routes.py
@@ -0,0 +1,138 @@
+from app import db
+from app.models.planet import Planet
+from app.models.moon import Moon
+from flask import Blueprint, jsonify, abort, make_response, request
+from sqlalchemy import desc, asc
+
+
+# ---------helper functions--------
+def sort_planet_query(planet_query, sort_query, order_query):
+    if not sort_query:
+        sort_query = "name"
+
+    if not order_query:
+        order_query = "asc"
+
+    if order_query == "desc":
+        planet_query = planet_query.order_by(desc(sort_query))
+    else:
+        planet_query = planet_query.order_by(asc(sort_query))
+
+    return planet_query
+
+
+
+def validate_model(cls, model_id):
+    try:
+        model_id = int(model_id)
+    except:
+        abort(make_response(jsonify({"message":f"{cls.__name__} {model_id} invalid"}), 400))
+
+    model = cls.query.get(model_id)
+
+    if not model:
+        abort(make_response(jsonify({"message":f"{cls.__name__} #{model_id} not found"}), 404))
+
+    return model
+
+
+# ------------route implementations-----------
+planets_bp = Blueprint("planets_bp", __name__, url_prefix="/planets")
+
+@planets_bp.route("", methods=["POST"])
+def create_planet():
+    request_body = request.get_json()
+
+    # if "name" not in request_body or "description" not in request_body or 'diameter_in_km' not in request_body:
+        # return make_response("Invalid Request", 400)
+    try:
+        new_planet = Planet.from_dict(request_body)
+    except KeyError as err:
+        abort(make_response({"message":f"Missing {err.args[0]}."}, 400))
+
+    db.session.add(new_planet)
+    db.session.commit()
+
+    return make_response(jsonify(f"Planet {new_planet.name} successfully created"), 201)
+
+
+@planets_bp.route("", methods=["GET"])
+def get_planets_optional_query():
+    planet_query = Planet.query
+    name_query = request.args.get("name")
+
+    if name_query:
+        planet_query = planet_query.filter(Planet.name.ilike(f"%{name_query}%"))
+
+    sort_query = request.args.get("sort")
+    order_query = request.args.get("order")
+
+    if sort_query or order_query:
+        planet_query = sort_planet_query(planet_query, sort_query, order_query)
+
+    planets = planet_query.all()
+    planets_response = []
+
+    for planet in planets:
+        planets_response.append(planet.to_dict())
+
+    return jsonify(planets_response)
+
+
+@planets_bp.route("/<planet_id>", methods=["GET"])
+def get_planet_by_id(planet_id):
+    planet = validate_model(Planet, planet_id)
+    return planet.to_dict()
+
+
+@planets_bp.route("/<planet_id>", methods=["PUT"])
+def update_planet(planet_id):
+    planet = validate_model(Planet, planet_id)
+    request_body = request.get_json()
+    planet.name = request_body["name"]
+    planet.description = request_body["description"]
+    planet.diameter_in_km = request_body["diameter_in_km"]
+
+    db.session.commit()
+    return make_response(jsonify(f"Planet #{planet_id} successfully updated."))
+
+
+@planets_bp.route("/<planet_id>", methods=["DELETE"])
+def delete_planet(planet_id):
+    planet = validate_model(Planet, planet_id)
+
+    db.session.delete(planet)
+    db.session.commit()
+    return make_response(jsonify(f"Planet #{planet_id} successfully deleted"))
+
+@planets_bp.route("/<planet_id>/moons", methods=["GET"])
+def get_all_moons_for_planet(planet_id):
+    planet = validate_model(Planet, planet_id)
+
+    moons_response = []
+    for moon in planet.moons:
+        moons_response.append(moon.to_dict())
+
+    return jsonify(moons_response)
+
+@planets_bp.route("/<planet_id>/moons", methods=["POST"])
+def add_new_moon_to_planet(planet_id):
+    planet = validate_model(Planet, planet_id)
+
+    request_body = request.get_json()
+    new_moon = Moon.from_dict(request_body)
+    new_moon.planet_id = planet_id
+
+    db.session.add(new_moon)
+    db.session.commit()
+
+    
+    return make_response(jsonify({"message": f"Moon {new_moon.name} created with planet {planet.name}"}), 201)
+
+
+# --------------for testing-----------------
+# planets = [
+#     Planet(id = 3, name = "Earth", description = "habitable", diameter = 12756),
+#     Planet(id = 1, name = "Mercury", description = "inhabitable", diameter = 4879),
+#     Planet(id = 4, name = "Mars", description = "inhabitable", diameter = 6792)
+# 
\ No newline at end of file
diff --git a/app/routes.py b/app/routes.py
deleted file mode 100644
index 8e9dfe684..000000000
--- a/app/routes.py
+++ /dev/null
@@ -1,2 +0,0 @@
-from flask import Blueprint
-
diff --git a/migrations/README b/migrations/README
new file mode 100644
index 000000000..98e4f9c44
--- /dev/null
+++ b/migrations/README
@@ -0,0 +1 @@
+Generic single-database configuration.
\ No newline at end of file
diff --git a/migrations/alembic.ini b/migrations/alembic.ini
new file mode 100644
index 000000000..f8ed4801f
--- /dev/null
+++ b/migrations/alembic.ini
@@ -0,0 +1,45 @@
+# A generic, single database configuration.
+
+[alembic]
+# template used to generate migration files
+# file_template = %%(rev)s_%%(slug)s
+
+# set to 'true' to run the environment during
+# the 'revision' command, regardless of autogenerate
+# revision_environment = false
+
+
+# Logging configuration
+[loggers]
+keys = root,sqlalchemy,alembic
+
+[handlers]
+keys = console
+
+[formatters]
+keys = generic
+
+[logger_root]
+level = WARN
+handlers = console
+qualname =
+
+[logger_sqlalchemy]
+level = WARN
+handlers =
+qualname = sqlalchemy.engine
+
+[logger_alembic]
+level = INFO
+handlers =
+qualname = alembic
+
+[handler_console]
+class = StreamHandler
+args = (sys.stderr,)
+level = NOTSET
+formatter = generic
+
+[formatter_generic]
+format = %(levelname)-5.5s [%(name)s] %(message)s
+datefmt = %H:%M:%S
diff --git a/migrations/env.py b/migrations/env.py
new file mode 100644
index 000000000..8b3fb3353
--- /dev/null
+++ b/migrations/env.py
@@ -0,0 +1,96 @@
+from __future__ import with_statement
+
+import logging
+from logging.config import fileConfig
+
+from sqlalchemy import engine_from_config
+from sqlalchemy import pool
+from flask import current_app
+
+from alembic import context
+
+# this is the Alembic Config object, which provides
+# access to the values within the .ini file in use.
+config = context.config
+
+# Interpret the config file for Python logging.
+# This line sets up loggers basically.
+fileConfig(config.config_file_name)
+logger = logging.getLogger('alembic.env')
+
+# add your model's MetaData object here
+# for 'autogenerate' support
+# from myapp import mymodel
+# target_metadata = mymodel.Base.metadata
+config.set_main_option(
+    'sqlalchemy.url',
+    str(current_app.extensions['migrate'].db.engine.url).replace('%', '%%'))
+target_metadata = current_app.extensions['migrate'].db.metadata
+
+# other values from the config, defined by the needs of env.py,
+# can be acquired:
+# my_important_option = config.get_main_option("my_important_option")
+# ... etc.
+
+
+def run_migrations_offline():
+    """Run migrations in 'offline' mode.
+
+    This configures the context with just a URL
+    and not an Engine, though an Engine is acceptable
+    here as well.  By skipping the Engine creation
+    we don't even need a DBAPI to be available.
+
+    Calls to context.execute() here emit the given string to the
+    script output.
+
+    """
+    url = config.get_main_option("sqlalchemy.url")
+    context.configure(
+        url=url, target_metadata=target_metadata, literal_binds=True
+    )
+
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+def run_migrations_online():
+    """Run migrations in 'online' mode.
+
+    In this scenario we need to create an Engine
+    and associate a connection with the context.
+
+    """
+
+    # this callback is used to prevent an auto-migration from being generated
+    # when there are no changes to the schema
+    # reference: http://alembic.zzzcomputing.com/en/latest/cookbook.html
+    def process_revision_directives(context, revision, directives):
+        if getattr(config.cmd_opts, 'autogenerate', False):
+            script = directives[0]
+            if script.upgrade_ops.is_empty():
+                directives[:] = []
+                logger.info('No changes in schema detected.')
+
+    connectable = engine_from_config(
+        config.get_section(config.config_ini_section),
+        prefix='sqlalchemy.',
+        poolclass=pool.NullPool,
+    )
+
+    with connectable.connect() as connection:
+        context.configure(
+            connection=connection,
+            target_metadata=target_metadata,
+            process_revision_directives=process_revision_directives,
+            **current_app.extensions['migrate'].configure_args
+        )
+
+        with context.begin_transaction():
+            context.run_migrations()
+
+
+if context.is_offline_mode():
+    run_migrations_offline()
+else:
+    run_migrations_online()
diff --git a/migrations/script.py.mako b/migrations/script.py.mako
new file mode 100644
index 000000000..2c0156303
--- /dev/null
+++ b/migrations/script.py.mako
@@ -0,0 +1,24 @@
+"""${message}
+
+Revision ID: ${up_revision}
+Revises: ${down_revision | comma,n}
+Create Date: ${create_date}
+
+"""
+from alembic import op
+import sqlalchemy as sa
+${imports if imports else ""}
+
+# revision identifiers, used by Alembic.
+revision = ${repr(up_revision)}
+down_revision = ${repr(down_revision)}
+branch_labels = ${repr(branch_labels)}
+depends_on = ${repr(depends_on)}
+
+
+def upgrade():
+    ${upgrades if upgrades else "pass"}
+
+
+def downgrade():
+    ${downgrades if downgrades else "pass"}
diff --git a/migrations/versions/224c8797ae08_add_planet_model.py b/migrations/versions/224c8797ae08_add_planet_model.py
new file mode 100644
index 000000000..745509c58
--- /dev/null
+++ b/migrations/versions/224c8797ae08_add_planet_model.py
@@ -0,0 +1,34 @@
+"""Add Planet model
+
+Revision ID: 224c8797ae08
+Revises: 
+Create Date: 2022-12-20 14:21:01.763332
+
+"""
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision = '224c8797ae08'
+down_revision = None
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.create_table('planet',
+    sa.Column('id', sa.Integer(), autoincrement=True, nullable=False),
+    sa.Column('name', sa.String(), nullable=False),
+    sa.Column('description', sa.String(), nullable=True),
+    sa.Column('diameter_in_km', sa.Integer(), nullable=True),
+    sa.PrimaryKeyConstraint('id')
+    )
+    # ### end Alembic commands ###
+
+
+def downgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_table('planet')
+    # ### end Alembic commands ###
diff --git a/migrations/versions/2734fb2348a0_adds_moon_model.py b/migrations/versions/2734fb2348a0_adds_moon_model.py
new file mode 100644
index 000000000..c52ae712e
--- /dev/null
+++ b/migrations/versions/2734fb2348a0_adds_moon_model.py
@@ -0,0 +1,36 @@
+"""adds Moon model
+
+Revision ID: 2734fb2348a0
+Revises: 224c8797ae08
+Create Date: 2023-01-05 14:40:19.153903
+
+"""
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision = '2734fb2348a0'
+down_revision = '224c8797ae08'
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.create_table('moon',
+    sa.Column('id', sa.Integer(), autoincrement=True, nullable=False),
+    sa.Column('size', sa.Integer(), nullable=True),
+    sa.Column('description', sa.String(), nullable=True),
+    sa.Column('name', sa.String(), nullable=True),
+    sa.Column('planet_id', sa.Integer(), nullable=True),
+    sa.ForeignKeyConstraint(['planet_id'], ['moon.id'], ),
+    sa.PrimaryKeyConstraint('id')
+    )
+    # ### end Alembic commands ###
+
+
+def downgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_table('moon')
+    # ### end Alembic commands ###
diff --git a/requirements.txt b/requirements.txt
index fba2b3e38..f1c31b3f2 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,18 +1,25 @@
 alembic==1.5.4
+attrs==22.1.0
 autopep8==1.5.5
 blinker==1.4
 certifi==2020.12.5
 chardet==4.0.0
 click==7.1.2
+coverage==6.5.0
 Flask==1.1.2
 Flask-Migrate==2.6.0
 Flask-SQLAlchemy==2.4.4
+gunicorn==20.1.0
 idna==2.10
+iniconfig==1.1.1
 itsdangerous==1.1.0
 Jinja2==2.11.3
 Mako==1.1.4
 MarkupSafe==1.1.1
+packaging==22.0
+pluggy==1.0.0
 psycopg2-binary==2.9.4
+py==1.11.0
 pycodestyle==2.6.0
 pytest==7.1.1
 pytest-cov==2.12.1
@@ -23,5 +30,6 @@ requests==2.25.1
 six==1.15.0
 SQLAlchemy==1.3.23
 toml==0.10.2
+tomli==2.0.1
 urllib3==1.26.4
 Werkzeug==1.0.1
diff --git a/tests/__init__.py b/tests/__init__.py
new file mode 100644
index 000000000..e69de29bb
diff --git a/tests/conftest.py b/tests/conftest.py
new file mode 100644
index 000000000..844382a84
--- /dev/null
+++ b/tests/conftest.py
@@ -0,0 +1,76 @@
+import pytest
+from app import create_app, db
+from flask.signals import request_finished
+from app.models.planet import Planet
+from app.models.moon import Moon
+
+@pytest.fixture
+def app():
+    app = create_app({"TESTING": True})
+
+    @request_finished.connect_via(app)
+    def expire_session(sender, response, **extra):
+        db.session.remove()
+
+    with app.app_context():
+        db.create_all()
+        yield app
+
+    with app.app_context():
+        db.drop_all()
+
+@pytest.fixture
+def client(app):
+    return app.test_client()
+
+@pytest.fixture
+def one_planet(app):
+    moon = Moon(
+        name = "Titan",
+        size = 1000,
+        description = "icy"
+    )
+
+    earth = Planet(
+        name = "Earth", 
+        description = "habitable", 
+        diameter_in_km = 12756,
+        moons = [moon]
+    )
+
+    db.session.add(earth)
+    db.session.commit()
+    return earth
+
+
+@pytest.fixture
+def two_planets(app):
+    earth = Planet(
+        name = "Earth", 
+        description = "habitable", 
+        diameter_in_km = 12756
+    )
+
+    mars = Planet(
+        name = "Mars", 
+        description = "inhabitable", 
+        diameter_in_km = 6792
+    )
+
+    db.session.add_all([earth, mars])
+    db.session.commit()
+    db.session.refresh(earth, ["id"])
+    db.session.refresh(mars, ["id"])
+    
+
+@pytest.fixture
+def one_moon(app):
+    moon = Moon(
+        name = "Titan",
+        size = 1000,
+        description = "icy"
+    )
+
+    db.session.add(moon)
+    db.session.commit()
+    return moon
\ No newline at end of file
diff --git a/tests/test_models.py b/tests/test_models.py
new file mode 100644
index 000000000..d06857258
--- /dev/null
+++ b/tests/test_models.py
@@ -0,0 +1,125 @@
+from app.models.planet import Planet
+import pytest
+
+
+def test_from_dict_returns_planet():
+    # Arrange
+    planet_data = {
+        'name': "Earth", 
+        'description':"habitable", 
+        'diameter_in_km': 12756
+    }
+
+    # Act
+    new_planet = Planet.from_dict(planet_data)
+
+    # Assert
+    assert new_planet.name == "Earth"
+    assert new_planet.description == "habitable"
+    assert new_planet.diameter_in_km == 12756
+
+def test_from_dict_with_no_name():
+    # Arrange
+    planet_data = {
+        'description':"habitable", 
+        'diameter_in_km': 12756
+    }
+
+    # Act & Assert
+    with pytest.raises(KeyError, match = 'name'):
+        new_planet = Planet.from_dict(planet_data)
+
+def test_from_dict_with_no_description():
+    # Arrange
+    planet_data = {
+        "name": "Earth",
+        'diameter_in_km': 12756
+    }
+
+    # Act & Assert
+    with pytest.raises(KeyError, match = 'description'):
+        new_planet = Planet.from_dict(planet_data)
+
+def test_from_dict_with_extra_keys():
+    # Arrange
+    planet_data = {
+        'name': "Earth", 
+        'description':"habitable", 
+        'diameter_in_km': 12756,
+        'has_air': True
+    }
+    
+    # Act
+    new_planet = Planet.from_dict(planet_data)
+
+    # Assert
+    assert new_planet.name == 'Earth'
+    assert new_planet.description == "habitable"
+    assert new_planet.diameter_in_km == 12756
+
+def test_to_dict_no_missing_data():
+    # Arrange
+    test_data = Planet(
+        id = 1,
+        name = "Earth", 
+        description = "habitable", 
+        diameter_in_km = 12756)
+
+    # Act
+    result = test_data.to_dict()
+
+    # Assert
+    assert len(result) == 5
+    assert result["id"] == 1
+    assert result["name"] == "Earth"
+    assert result["description"] == "habitable"
+    assert result["diameter_in_km"] == 12756
+
+def test_to_dict_missing_id():
+    # Arrange
+    test_data = Planet(
+        name = "Earth", 
+        description = "habitable", 
+        diameter_in_km = 12756)
+
+    # Act
+    result = test_data.to_dict()
+
+    # Assert
+    assert len(result) == 5
+    assert result["id"] is None
+    assert result["name"] == "Earth"
+    assert result["description"] == "habitable"
+    assert result["diameter_in_km"] == 12756
+
+def test_to_dict_missing_name():
+    # Arrange
+    test_data = Planet(id=1,
+                    description = "habitable", 
+                    diameter_in_km = 12756)
+
+    # Act
+    result = test_data.to_dict()
+
+    # Assert
+    assert len(result) == 5
+    assert result["id"] == 1
+    assert result["name"] is None
+    assert result["description"] == "habitable"
+    assert result["diameter_in_km"] == 12756
+
+def test_to_dict_missing_description():
+    # Arrange
+    test_data = Planet(id = 1,
+                    name = "Earth", 
+                    diameter_in_km = 12756)
+
+    # Act
+    result = test_data.to_dict()
+
+    # Assert
+    assert len(result) == 5
+    assert result["id"] == 1
+    assert result["name"] == "Earth"
+    assert result["description"] is None
+    assert result["diameter_in_km"] == 12756
diff --git a/tests/test_routes.py b/tests/test_routes.py
new file mode 100644
index 000000000..948c077f3
--- /dev/null
+++ b/tests/test_routes.py
@@ -0,0 +1,182 @@
+import pytest
+
+def test_get_planets_optional_query_empty_db_returns_empty_list(client):
+    # Act
+    response = client.get("/planets")
+
+    # Assert
+    assert response.status_code == 200
+    assert response.get_json() == []
+
+def test_get_planets_optional_query_returns_seeded_planet(client, two_planets):
+    response = client.get("/planets")
+    planet_list = response.get_json()
+
+    assert response.status_code == 200
+    assert len(planet_list) == 2
+    assert planet_list[0]["id"] == 1 
+    assert planet_list[0]["name"] == "Earth"
+    assert planet_list[0]["description"] == "habitable"
+    assert planet_list[0]["diameter_in_km"] == 12756
+
+    assert planet_list[1]["id"] == 2 
+    assert planet_list[1]["name"] == "Mars"
+    assert planet_list[1]["description"] == "inhabitable"
+    assert planet_list[1]["diameter_in_km"] == 6792
+
+def test_get_planet_optional_query_missing_record_returns_404(client, two_planets):
+    response = client.get("/planets/3")
+    response_body = response.get_json()
+
+    assert response.status_code == 404
+    assert response_body == {"message":"Planet #3 not found"}
+
+def test_get_planet_by_id_returns_200_with_matching_response(client, two_planets):
+    response = client.get("/planets/1")
+    planet_list = response.get_json()
+
+    assert response.status_code == 200
+    assert planet_list == {
+        "id": 1,
+        "name": "Earth",
+        "description": "habitable",
+        "diameter_in_km": 12756,
+        "moons": []
+    }
+
+def test_get_planet_by_id_invalid_id_returns_400(client, two_planets):
+    # Act
+    response = client.get("/planets/earth")
+    response_body = response.get_json()
+
+    # Assert
+    assert response.status_code == 400
+    assert response_body == {"message": "Planet earth invalid"}
+
+def test_create_planet_returns_201(client):
+    test_data = {
+        "name": "Mercury", 
+        "description": "inhabitable", 
+        "diameter_in_km": 4879
+    }
+    response = client.post("/planets", json=test_data)
+    response_body = response.get_json()
+
+    assert response.status_code == 201
+    assert response_body == "Planet Mercury successfully created"
+
+def test_update_planet_returns_200(client, two_planets):
+    test_data = {
+        "name": "Mercury", 
+        "description": "inhabitable", 
+        "diameter_in_km": 4879
+    }
+
+    response = client.put("/planets/1", json=test_data)
+    response_body = response.get_json()
+
+    assert response.status_code == 200
+    assert response_body == "Planet #1 successfully updated."
+
+def test_update_planet_invalid_id_returns_400(client, two_planets):
+    test_data = {
+        "name": "Mercury", 
+        "description": "inhabitable", 
+        "diameter_in_km": 4879
+    }
+
+    response = client.put("/planets/earth", json=test_data)
+    response_body = response.get_json()
+
+    assert response.status_code == 400
+    assert response_body == {"message": "Planet earth invalid"}
+
+def test_delete_planet_returns_200(client, two_planets):
+    response = client.delete("/planets/1")
+    response_body = response.get_json()
+
+    assert response.status_code == 200
+    assert response_body == "Planet #1 successfully deleted"
+
+def test_delete_planet_returns_404(client, two_planets):
+    response = client.delete("/planets/3")
+    response_body = response.get_json()
+
+    assert response.status_code == 404
+    assert response_body == {"message":"Planet #3 not found"}
+
+def test_delete_planet_invalid_id_returns_400(client, two_planets):
+    response = client.delete("/planets/earth")
+    response_body = response.get_json()
+
+    assert response.status_code == 400
+    assert response_body == {"message": "Planet earth invalid"}
+
+def test_update_planet_missing_planet_returns_404(client, two_planets):
+    test_data = {
+        "name": "Mercury", 
+        "description": "inhabitable", 
+        "diameter_in_km": 4879
+    }
+
+    response = client.put("/planets/3", json=test_data)
+    response_body = response.get_json()
+
+    assert response.status_code == 404
+    assert response_body == {"message":"Planet #3 not found"}
+
+def test_create_planet_missing_name_attribute(client):
+    test_data = {
+        "description": 'habitable', 
+        "diameter_in_km": 12345
+    }
+
+    response = client.post("/planets", json=test_data)
+    response_body = response.get_json()
+    assert response.status_code == 400 
+    assert response_body == {"message":"Missing name."}
+
+def test_create_planet_missing_description_attribute(client, two_planets):
+    test_data = {
+        "name": "Mars", 
+        "diameter_in_km": 12345
+    }
+    response = client.post("/planets", json=test_data)
+    response_body = response.get_json()
+    assert response.status_code == 400 
+    assert response_body == {"message":"Missing description."}
+
+def test_create_planet_missing_diameter_in_km_attribute(client):
+    test_data = {
+        "name": "Mars",
+        "description": 'habitable'
+    }
+    response = client.post("/planets", json=test_data)
+    response_body = response.get_json()
+    assert response.status_code == 400 
+    assert response_body == {"message":"Missing diameter_in_km."}
+
+
+# testing nested routes
+def test_add_new_moon_to_planet_returns_201(client, two_planets):
+    test_data = {
+        "name": "Titan",
+        "size": 1000,
+        "description": "icy"
+    }
+    response = client.post("/planets/2/moons", json=test_data)
+    response_body = response.get_json()
+    assert response.status_code == 201
+    assert response_body == {"message": "Moon Titan created with planet Mars"}
+
+
+def test_get_all_moons_for_planet_returns_201(client, one_planet):
+    response = client.get("/planets/1/moons")
+    response_body = response.get_json()
+
+    assert response.status_code == 200
+    assert response_body[0]["name"] == "Titan"
+    assert response_body[0]["size"] == 1000
+    assert response_body[0]["description"] == "icy"
+
+