Python codegen support (#923)

* Initial python codegen support
* Add python tests CI job

Author: robholt

.github/workflows/ci-python.yml

@@ -0,0 +1,40 @@
+name: python
+on: [push, pull_request]
+jobs:
+
+  build:
+    name: test
+    runs-on: ubuntu-latest
+
+    services:
+      postgres:
+        image: postgres:11
+        env:
+          POSTGRES_USER: postgres
+          POSTGRES_PASSWORD: postgres
+          POSTGRES_DB: postgres
+        ports:
+          - 5432:5432
+        # needed because the postgres container does not provide a healthcheck
+        options: --health-cmd pg_isready --health-interval 10s --health-timeout 5s --health-retries 5
+
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-python@v2
+        with:
+          python-version: 3.9
+      - name: Install python dependencies
+        working-directory: ./examples/python
+        run: |
+          python -m pip install --upgrade pip
+          python -m pip install -r requirements.txt
+      - name: Test python code
+        working-directory: ./examples/python
+        env:
+          PG_USER: postgres
+          PG_HOST: localhost
+          PG_DATABASE: postgres
+          PG_PASSWORD: postgres
+          PG_PORT: ${{ job.services.postgres.ports['5432'] }}
+        run: |
+          pytest src/tests

examples/python/requirements.txt

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+pytest~=6.2.2
+pytest-asyncio~=0.14.0
+psycopg2-binary~=2.8.6
+asyncpg~=0.21.0
+pydantic~=1.7.3
+sqlc-python-runtime~=1.0.0

examples/python/sqlc.json

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+{
+  "version": "2",
+  "sql": [
+    {
+      "schema": "../authors/postgresql/schema.sql",
+      "queries": "../authors/postgresql/query.sql",
+      "engine": "postgresql",
+      "gen": {
+        "python": {
+          "out": "src/authors",
+          "package": "authors"
+        }
+      }
+    },
+    {
+      "schema": "../booktest/postgresql/schema.sql",
+      "queries": "../booktest/postgresql/query.sql",
+      "engine": "postgresql",
+      "gen": {
+        "python": {
+          "out": "src/booktest",
+          "package": "booktest"
+        }
+      }
+    },
+    {
+      "schema": "../jets/schema.sql",
+      "queries": "../jets/query-building.sql",
+      "engine": "postgresql",
+      "gen": {
+        "python": {
+          "out": "src/jets",
+          "package": "jets"
+        }
+      }
+    },
+    {
+      "schema": "../ondeck/postgresql/schema",
+      "queries": "../ondeck/postgresql/query",
+      "engine": "postgresql",
+      "gen": {
+        "python": {
+          "out": "src/ondeck",
+          "package": "ondeck"
+        }
+      }
+    }
+  ]
+}

examples/python/src/authors/__init__.py

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+# Code generated by sqlc. DO NOT EDIT.
+from typing import Optional
+
+import pydantic
+
+
+# Enums
+
+# Models
+class Author(pydantic.BaseModel):
+    id: int
+    name: str
+    bio: Optional[str]
+
+

examples/python/src/authors/models.py

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+# Code generated by sqlc. DO NOT EDIT.
+from typing import AsyncIterator, Awaitable, Iterator, Optional, overload
+
+import sqlc_runtime as sqlc
+
+from authors import models
+
+
+CREATE_AUTHOR = """-- name: create_author :one
+INSERT INTO authors (
+          name, bio
+) VALUES (
+  $1, $2
+)
+RETURNING id, name, bio
+"""
+
+
+DELETE_AUTHOR = """-- name: delete_author :exec
+DELETE FROM authors
+WHERE id = $1
+"""
+
+
+GET_AUTHOR = """-- name: get_author :one
+SELECT id, name, bio FROM authors
+WHERE id = $1 LIMIT 1
+"""
+
+
+LIST_AUTHORS = """-- name: list_authors :many
+SELECT id, name, bio FROM authors
+ORDER BY name
+"""
+
+
+@overload
+def create_author(conn: sqlc.Connection, name: str, bio: Optional[str]) -> Optional[models.Author]:
+    pass
+
+
+@overload
+def create_author(conn: sqlc.AsyncConnection, name: str, bio: Optional[str]) -> Awaitable[Optional[models.Author]]:
+    pass
+
+
+def create_author(conn: sqlc.GenericConnection, name: str, bio: Optional[str]) -> sqlc.ReturnType[Optional[models.Author]]:
+    return conn.execute_one_model(models.Author, CREATE_AUTHOR, name, bio)
+
+
+@overload
+def delete_author(conn: sqlc.Connection, id: int) -> None:
+    pass
+
+
+@overload
+def delete_author(conn: sqlc.AsyncConnection, id: int) -> Awaitable[None]:
+    pass
+
+
+def delete_author(conn: sqlc.GenericConnection, id: int) -> sqlc.ReturnType[None]:
+    return conn.execute_none(DELETE_AUTHOR, id)
+
+
+@overload
+def get_author(conn: sqlc.Connection, id: int) -> Optional[models.Author]:
+    pass
+
+
+@overload
+def get_author(conn: sqlc.AsyncConnection, id: int) -> Awaitable[Optional[models.Author]]:
+    pass
+
+
+def get_author(conn: sqlc.GenericConnection, id: int) -> sqlc.ReturnType[Optional[models.Author]]:
+    return conn.execute_one_model(models.Author, GET_AUTHOR, id)
+
+
+@overload
+def list_authors(conn: sqlc.Connection) -> Iterator[models.Author]:
+    pass
+
+
+@overload
+def list_authors(conn: sqlc.AsyncConnection) -> AsyncIterator[models.Author]:
+    pass
+
+
+def list_authors(conn: sqlc.GenericConnection) -> sqlc.IteratorReturn[models.Author]:
+    return conn.execute_many_model(models.Author, LIST_AUTHORS)
+
+

examples/python/src/authors/query.py

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+# Code generated by sqlc. DO NOT EDIT.
+from typing import List
+import datetime
+import enum
+
+import pydantic
+
+
+# Enums
+class BookType(str, enum.Enum):
+    FICTION = "FICTION"
+    NONFICTION = "NONFICTION"
+
+
+# Models
+class Author(pydantic.BaseModel):
+    author_id: int
+    name: str
+
+
+class Book(pydantic.BaseModel):
+    book_id: int
+    author_id: int
+    isbn: str
+    book_type: BookType
+    title: str
+    year: int
+    available: datetime.datetime
+    tags: List[str]
+
+