Downloading a schema

Apollo iOS requires a GraphQL schema file as input to the code generation process. A schema file is a JSON file that contains the results of an introspection query. Conventionally this file is called schema.json, and you store it next to the .graphql files in your target.

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You can use apollo from the apollo-cli package to download a GraphQL schema by sending an introspection query to the server.

If you've installed the CLI globally, you can use the following command to download your schema:

apollo schema:download --endpoint=http://localhost:8080/graphql schema.json

Note that if you're using the local version set up for codegen, you'll want to use the same method you're using in the Adding A Code Generation Build Step instructions to access that specific CLI. For example, if you're using CocoaPods, you can set it up like this to download your schema:

SCRIPT_PATH="${PODS_ROOT}/Apollo/scripts"
cd "${SRCROOT}/${TARGET_NAME}"
"${SCRIPT_PATH}"/run-bundled-codegen.sh schema:download --endpoint=http://localhost:8080/graphql schema.json

If needed, you can use the header option to add additional HTTP headers to the request. For example, to include an authentication token, use --header "Authorization: Bearer <token>":

[your apollo version] schema:download --endpoint=http://localhost:8080/graphql --header="Authorization: Bearer <token>"