Add customSubsciptionResolvers option

Signed-off-by: Alan Cha <[email protected]>

Author: Alan-Cha

packages/openapi-to-graphql/README.md

@@ -164,6 +164,8 @@ Schema options:
 
 - `singularNames` (type: `boolean`, default: `false`): Experimental feature that will try to create more meaningful names from the operation path than the response object by leveraging common conventions. For example, given the operation `GET /users/{userId}/car`, OtG will create a `Query` field `userCar`. Note that because `users` is followed by the parameter `userId`, it insinuates that this operation will get the car that belongs to a singular user. Hence, the name `userCar` is more fitting than `usersCar` so the pluralizing 's' is dropped. This option will also consider irregular plural forms.
 
+- `createSubscriptionsFromCallbacks` (type: `boolean`, default: `false`): Generates subscription fields from [callback objects](https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.2.md#CallbackObject). The keys ([runtime expressions](https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.2.md#runtimeExpression)) of the callback objects will be interpolated as the topic of a publish/subscription connection using [graphql-subscriptions](https://github.com/apollographql/graphql-subscriptions). Read the [doc](./docs/subscriptions.md) for explanations and examples regarding its usage.
+
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 Resolver options:
@@ -176,9 +178,9 @@ Resolver options:
 
 - `baseUrl` (type: `string`): Used to manually specify the base URL which all paths will be built on. Normally, OpenAPI-to-GraphQL will select a base URL from the [server object](https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.2.md#serverObject) defined in the OAS. However, if the server object contains multiple URLs, OpenAPI-to-GraphQL will randomly select one. The purpose of this option is to provide greater control over the base URL in these situations, especially when the OAS cannot be modified. This option may also prove to be useful in testing and development.
 
-- `customResolvers` (type: `object`, default: `{}`): OpenAPI-to-GraphQL, by default, creates resolver functions that make REST calls to resolve fields in the generated GraphQL interface. This option allows users to provide custom resolver functions to be used in place of said ones created by OpenAPI-to-GraphQL. The field that the custom resolver will affect is identifed first by the [title](https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.2.md#infoObject) of the OAS, then the [path](https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.2.md#paths-object) of the operation, and lastly the [method](https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.2.md#path-item-object) of the operation. The `customResolvers` object is thus a triply nested object where the outer key is the title, followed by the path, and finally the method, which points to the [resolver function](https://graphql.org/learn/execution/#root-fields-resolvers) itself. The resolver function can use the parameters `obj`, `args`, `context`, and `info` in order to produce the proper data, as do standard [resolver functions](https://graphql.org/learn/execution/#root-fields-resolvers) in GraphQL. Use cases include the resolution of complex relationships between types, implementing performance improvements like caching, or dealing with non-standard authentication requirements. _Note: Because the arguments are provided by the GraphQL interface, they may look different from the [parameters](https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.2.md#parameterObject) defined by the OAS. For example, they will have [sanitized](https://github.com/Alan-Cha/openapi-to-graphql#characteristics) names. The [request body](https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.2.md#requestBodyObject) will also be contained in the arguments as an [input object type](https://graphql.org/graphql-js/mutations-and-input-types/)._
+- `customResolvers` (type: `object`, default: `{}`): OpenAPI-to-GraphQL, by default, creates resolver functions that make REST calls to resolve Query and Mutation fields in the generated GraphQL interface. This option allows users to provide custom resolver functions to be used in place of said ones created by OpenAPI-to-GraphQL. The field that the custom resolver will affect is identifed first by the [title](https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.2.md#infoObject) of the OAS, then the [path](https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.2.md#paths-object) of the operation, and lastly the [method](https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.2.md#path-item-object) of the operation. The `customResolvers` object is thus a triply nested object where the outer key is the title, followed by the path, and finally the method, which points to the [resolver function](https://graphql.org/learn/execution/#root-fields-resolvers) itself. The resolver function can use the parameters `obj`, `args`, `context`, and `info` in order to produce the proper data, as do standard [resolver functions](https://graphql.org/learn/execution/#root-fields-resolvers) in GraphQL. Use cases include the resolution of complex relationships between types, implementing performance improvements like caching, or dealing with non-standard authentication requirements. _Note: Because the arguments are provided by the GraphQL interface, they may look different from the [parameters](https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.2.md#parameterObject) defined by the OAS. For example, they will have [sanitized](https://github.com/Alan-Cha/openapi-to-graphql#characteristics) names. The [request body](https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.2.md#requestBodyObject) will also be contained in the arguments as an [input object type](https://graphql.org/graphql-js/mutations-and-input-types/)._
 
-- `createSubscriptionsFromCallbacks` (type: `boolean`, default: `false`): Generates subscription fields from [callback objects](https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.2.md#CallbackObject). The keys ([runtime expressions](https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.2.md#runtimeExpression)) of the callback objects will be interpolated as the topic of a publish/subscription connection using [graphql-subscriptions](https://github.com/apollographql/graphql-subscriptions). Read the [doc](./docs/subscriptions.md) for explanations and examples regarding its usage.
+- `customSubscriptionResolvers` (type: `object`, default: `{}`): If the `createSubscriptionsFromCallbacks` is enabled, OpenAPI-to-GraphQL will generate Subscription fields. This option allows users to provide custom resolver and subscribe functions to be used in place of said ones created by OpenAPI-to-GraphQL. The field that the custom resolver will affect is identifed first by the [title](https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.2.md#infoObject) of the OAS, then the [path](https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.2.md#paths-object) of the operation, and lastly the [method](https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.2.md#path-item-object) of the operation. The `customSubscriptionResolvers` object is thus a triply nested object where the outer key is the title, followed by the path, and finally the method, which points to the [resolver function](https://graphql.org/learn/execution/#root-fields-resolvers) itself. The resolver function can use the parameters `obj`, `args`, `context`, and `info` in order to produce the proper data, as do standard [resolver functions](https://graphql.org/learn/execution/#root-fields-resolvers) in GraphQL. Use cases include the resolution of complex relationships between types, implementing performance improvements like caching, or dealing with non-standard authentication requirements. _Note: Because the arguments are provided by the GraphQL interface, they may look different from the [parameters](https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.2.md#parameterObject) defined by the OAS. For example, they will have [sanitized](https://github.com/Alan-Cha/openapi-to-graphql#characteristics) names. The [request body](https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.2.md#requestBodyObject) will also be contained in the arguments as an [input object type](https://graphql.org/graphql-js/mutations-and-input-types/)._
 
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