Introduce a apollo-server-plugin-base as a foundation for plugins.

package-lock.json

@@ -2176,6 +2176,7 @@
         "apollo-server-caching": "file:packages/apollo-server-caching",
         "apollo-server-env": "file:packages/apollo-server-env",
         "apollo-server-errors": "file:packages/apollo-server-errors",
+        "apollo-server-plugin-base": "file:packages/apollo-server-plugin-base",
         "apollo-tracing": "file:packages/apollo-tracing",
         "graphql-extensions": "file:packages/graphql-extensions",
         "graphql-subscriptions": "^0.5.8",
@@ -2321,6 +2322,9 @@
         "micro": "^9.3.2"
       }
     },
+    "apollo-server-plugin-base": {
+      "version": "file:packages/apollo-server-plugin-base"
+    },
     "apollo-tracing": {
       "version": "file:packages/apollo-tracing",
       "requires": {

packages/apollo-server-plugin-base/.npmignore

@@ -0,0 +1,6 @@
+*
+!src/**/*
+!dist/**/*
+dist/**/*.test.*
+!package.json
+!README.md

packages/apollo-server-plugin-base/CHANGELOG.md

@@ -0,0 +1,4 @@
+# Change Log
+
+### vNEXT
+

packages/apollo-server-plugin-base/README.md

@@ -0,0 +1 @@
+# `apollo-server-plugin-base`

packages/apollo-server-plugin-base/package.json

@@ -0,0 +1,21 @@
+{
+  "name": "apollo-server-plugin-base",
+  "version": "0.0.1",
+  "description": "Apollo Server plugin base classes",
+  "main": "dist/index.js",
+  "types": "dist/index.d.ts",
+  "scripts": {
+    "clean": "rm -rf dist",
+    "compile": "tsc",
+    "prepare": "npm run clean && npm run compile"
+  },
+  "keywords": [],
+  "author": "Apollo <opensource@apollographql.com>",
+  "license": "MIT",
+  "engines": {
+    "node": ">=6"
+  },
+  "dependencies": {
+    "apollo-server-caching": "file:../apollo-server-caching"
+  }
+}

packages/apollo-server-plugin-base/src/index.ts

@@ -0,0 +1,35 @@
+import { GraphQLSchema } from 'graphql';
+import { KeyValueCache } from 'apollo-server-caching';
+
+export abstract class ApolloServerPluginBase {
+  [key: string]: any;
+  constructor(public options?: any) {}
+  serverWillStart?(parent: any): void;
+}
+
+interface ApolloServerRequestListenerInterface {
+  start?(): void;
+}
+
+export abstract class ApolloServerRequestListenerBase
+  implements ApolloServerRequestListenerInterface {
+  constructor() {}
+  start?(): void;
+}
+
+interface PluginEventBase {
+  name: string;
+  args?: any;
+}
+
+export interface PluginEventServerWillStart extends PluginEventBase {
+  args: {
+    schema: GraphQLSchema;
+    persistedQueries?: {
+      cache: KeyValueCache;
+    };
+    engine?: any;
+  };
+}
+
+export type PluginEvent = PluginEventServerWillStart;

packages/apollo-server-plugin-base/tsconfig.json

@@ -0,0 +1,9 @@
+{
+  "extends": "../../tsconfig",
+  "compilerOptions": {
+    "rootDir": "./src",
+    "outDir": "./dist"
+  },
+  "include": ["src/**/*"],
+  "exclude": ["**/__tests__", "**/__mocks__"]
+}