auto_camelcase plugin setting, closes #15

Also added basic configuration validation, refs #4

README.md

@@ -18,7 +18,11 @@ Install this plugin in the same environment as Datasette.
 
 ## Usage
 
-This sets up `/graphql` as a GraphQL endpoint for the first attached database. Individual tables can be queried like this:
+This plugin up `/graphql` as a GraphQL endpoint for the first attached database.
+
+### Querying for tables and columns
+
+Individual tables can be queried like this:
 ```grophql
 {
   repos {
@@ -29,6 +33,8 @@ This sets up `/graphql` as a GraphQL endpoint for the first attached database. I
 }
 ```
 
+### Accessing nested objects
+
 If a column is a foreign key to another table, you can request columns of that table using a nested query like this:
 ```graphql
 {
@@ -43,6 +49,8 @@ If a column is a foreign key to another table, you can request columns of that t
 }
 ```
 
+### Filtering tables
+
 You can filter the rows returned for a specific table using the `filters:` argument. This accepts a list of filters, where a filter is a string of the form `column=value` or `column__op=value`. For example, to return just repositories with the Apache 2 license and more than 10 stars:
 
 ```graphql
@@ -58,6 +66,25 @@ You can filter the rows returned for a specific table using the `filters:` argum
 ```
 This is the same format used for querystring arguments to the Datasette table view, see [column filter arguments](https://datasette.readthedocs.io/en/stable/json_api.html#column-filter-arguments) in the Datasette documentation.
 
+
+### Auto camelCase
+
+The names of your columns and tables default to being matched by their representations in GraphQL.
+
+If you have tables with `names_like_this` you may want to work with them in GraphQL using `namesLikeThis`, for consistency with GraphQL and JavaScript conventions.
+
+You can turn on automatic camelCase using the `"auto_camelcase"` plugin configuration setting in `metadata.json`, like this:
+
+```json
+{
+    "plugins": {
+        "datasette-graphql": {
+            "auto_camelcase": true
+        }
+    }
+}
+```
+
 ## Still to come
 
 See [issues](https://github.com/simonw/datasette-graphql/issues) for a full list. Planned improvements include:

datasette_graphql/__init__.py

@@ -1,3 +1,4 @@
+from click import ClickException
 from datasette import hookimpl
 from datasette.utils.asgi import Response
 from graphql.execution.executors.asyncio import AsyncioExecutor
@@ -51,3 +52,23 @@ def register_routes():
     return [
         (r"^/graphql$", view_graphql),
     ]
+
+
+@hookimpl
+def startup(datasette):
+    # Validate configuration
+    config = datasette.plugin_config("datasette-graphql") or {}
+    if "databases" in config:
+        if len(config["databases"].keys()) > 1:
+            raise ClickException(
+                "datasette-graphql currently only supports a single database"
+            )
+        database_name = list(config["databases"].keys())[0]
+        try:
+            datasette.get_database(database_name)
+        except KeyError:
+            raise ClickException(
+                "datasette-graphql config error: '{}' is not a connected database".format(
+                    database_name
+                )
+            )

datasette_graphql/utils.py

@@ -62,7 +62,12 @@ def introspect_table(conn):
     Query = type(
         "Query", (graphene.ObjectType,), {key: value for key, value in to_add},
     )
-    return graphene.Schema(query=Query, auto_camelcase=False)
+    return graphene.Schema(
+        query=Query,
+        auto_camelcase=(datasette.plugin_config("datasette-graphql") or {}).get(
+            "auto_camelcase", False
+        ),
+    )
 
 
 def make_all_rows_resolver(db, table, klass):

tests/fixtures.py

@@ -21,8 +21,20 @@ def db_path(tmp_path_factory):
     )
     db["repos"].insert_all(
         [
-            {"id": 1, "name": "datasette", "owner": 2, "license": "apache2"},
-            {"id": 2, "name": "dogspotter", "owner": 1, "license": "mit"},
+            {
+                "id": 1,
+                "full_name": "simonw/datasette",
+                "name": "datasette",
+                "owner": 2,
+                "license": "apache2",
+            },
+            {
+                "id": 2,
+                "full_name": "cleopaws/dogspotter",
+                "name": "dogspotter",
+                "owner": 1,
+                "license": "mit",
+            },
         ],
         pk="id",
         foreign_keys=(("owner", "users"), ("license", "licenses")),

tests/test_graphql.py

@@ -144,3 +144,47 @@ async def test_graphql_error(ds):
                 }
             ],
         }
+
+
+@pytest.mark.asyncio
+@pytest.mark.parametrize(
+    "on,expected",
+    [
+        (
+            True,
+            {
+                "repos": [
+                    {"id": 1, "fullName": "simonw/datasette"},
+                    {"id": 2, "fullName": "cleopaws/dogspotter"},
+                ]
+            },
+        ),
+        (
+            False,
+            {
+                "repos": [
+                    {"id": 1, "full_name": "simonw/datasette"},
+                    {"id": 2, "full_name": "cleopaws/dogspotter"},
+                ]
+            },
+        ),
+    ],
+)
+async def test_graphql_auto_camelcase(db_path, on, expected):
+    ds = Datasette(
+        [db_path], metadata={"plugins": {"datasette-graphql": {"auto_camelcase": on}}}
+    )
+    query = """
+    {
+        repos {
+            id
+            NAME
+        }
+    }
+    """.replace(
+        "NAME", "fullName" if on else "full_name"
+    )
+    async with httpx.AsyncClient(app=ds.app()) as client:
+        response = await client.post("http://localhost/graphql", json={"query": query})
+        assert response.status_code == 200
+        assert response.json() == {"data": expected}