feat: support fine-grained quirks mode

Author: vwong

src/compare/requestBody.ts

@@ -4,6 +4,7 @@ import type { OpenAPIV2 } from "openapi-types";
 import type Router from "find-my-way";
 import { get } from "lodash-es";
 import qs from "qs";
+import querystring from "node:querystring";
 import multipart from "parse-multipart-data";
 
 import type { Interaction } from "../documents/pact";
@@ -15,6 +16,7 @@ import {
   formatSchemaPath,
 } from "../results/index";
 import { minimumSchema, transformRequestSchema } from "../transform/index";
+import { config } from "../utils/config";
 import { isValidRequest } from "../utils/interaction";
 import { dereferenceOas, splitPath } from "../utils/schema";
 import { getValidateFunction } from "../utils/validation";
@@ -25,11 +27,12 @@ const parseBody = (body: unknown, contentType: string) => {
     contentType.includes("application/x-www-form-urlencoded") &&
     typeof body === "string"
   ) {
-    return qs.parse(body as string, {
-      allowDots: true,
-      comma: true,
-      depth: process.env.QUIRKS ? 0 : undefined,
-    });
+    return config.get("legacyParser")
+      ? querystring.parse(body as string)
+      : qs.parse(body as string, {
+          allowDots: true,
+          comma: true,
+        });
   }
 
   if (contentType.includes("multipart/form-data") && typeof body === "string") {
@@ -60,7 +63,7 @@ const canValidate = (contentType: string): boolean => {
     [
       "application/json",
       "application/x-www-form-urlencoded",
-      process.env.QUIRKS ? "" : "multipart/form-data",
+      config.get("disableMultipartFormdata") ? "" : "multipart/form-data",
     ].filter(Boolean),
   );
 };
@@ -110,7 +113,7 @@ export function* compareReqBody(
     schema &&
     canValidate(contentType) &&
     isValidRequest(interaction) &&
-    (process.env.QUIRKS
+    (config.get("noValidateRequestBodyUnlessApplicationJson")
       ? !!findMatchingType("application/json", availableRequestContentTypes)
       : true)
   ) {
@@ -147,7 +150,7 @@ export function* compareReqBody(
     !!body &&
     !schema &&
     isValidRequest(interaction) &&
-    (process.env.QUIRKS
+    (config.get("noValidateRequestBodyUnlessApplicationJson")
       ? !!findMatchingType("application/json", availableRequestContentTypes) ||
         availableRequestContentTypes.length === 0
       : true)

src/compare/requestHeader.ts

@@ -14,7 +14,8 @@ import {
 } from "../results/index";
 import { minimumSchema } from "../transform/index";
 import { isValidRequest } from "../utils/interaction";
-import { isQuirky } from "../utils/quirks";
+import { config } from "../utils/config";
+import { isSimpleSchema } from "../utils/quirks";
 import { dereferenceOas, splitPath } from "../utils/schema";
 import { getValidateFunction } from "../utils/validation";
 import { findMatchingType, standardHttpRequestHeaders } from "./utils/content";
@@ -317,7 +318,9 @@ export function* compareReqHeader(
     if (value !== null && schema && isValidRequest(interaction)) {
       const schemaId = `[root].paths.${path}.${method}.parameters[${parameterIndex}]`;
       const validate = getValidateFunction(ajv, schemaId, () =>
-        process.env.QUIRKS && value && isQuirky(schema)
+        config.get("noValidateComplexParameters") &&
+        isSimpleSchema(schema) &&
+        value
           ? {}
           : minimumSchema(schema, oas),
       );

src/compare/requestPath.ts

@@ -7,8 +7,9 @@ import type { Interaction } from "../documents/pact";
 import type { Result } from "../results/index";
 import { baseMockDetails } from "../results/index";
 import { minimumSchema } from "../transform/index";
+import { config } from "../utils/config";
 import { dereferenceOas } from "../utils/schema";
-import { isQuirky } from "../utils/quirks";
+import { isSimpleSchema } from "../utils/quirks";
 import { getValidateFunction } from "../utils/validation";
 import { cleanPathParameter } from "./utils/parameters";
 import { parseValue } from "./utils/parse";
@@ -44,7 +45,9 @@ export function* compareReqPath(
     if (schema) {
       const schemaId = `[root].paths.${path}.${method}.parameters[${parameterIndex}]`;
       const validate = getValidateFunction(ajv, schemaId, () =>
-        process.env.QUIRKS && value && isQuirky(schema)
+        config.get("noValidateComplexParameters") &&
+        isSimpleSchema(schema) &&
+        value
           ? {}
           : minimumSchema(schema, oas),
       );

src/compare/requestQuery.ts

@@ -14,9 +14,10 @@ import {
   formatSchemaPath,
 } from "../results/index";
 import { minimumSchema } from "../transform/index";
+import { config } from "../utils/config";
 import { isValidRequest } from "../utils/interaction";
 import { ARRAY_SEPARATOR } from "../utils/queryParams";
-import { isQuirky } from "../utils/quirks";
+import { isSimpleSchema } from "../utils/quirks";
 import { dereferenceOas, splitPath } from "../utils/schema";
 import { getValidateFunction } from "../utils/validation";
 
@@ -28,14 +29,14 @@ export function* compareReqQuery(
 ): Iterable<Result> {
   const { method, oas, operation, path, securitySchemes } = route.store;
 
-  const searchParamsParsed = process.env.QUIRKS
+  const searchParamsParsed = config.get("legacyParser")
     ? querystring.parse(route.searchParams as unknown as string)
     : qs.parse(route.searchParams, {
         allowDots: true,
         comma: true,
       });
 
-  const searchParamsUnparsed = process.env.QUIRKS
+  const searchParamsUnparsed = config.get("legacyParser")
     ? querystring.parse(route.searchParams as unknown as string)
     : qs.parse(route.searchParams, {
         allowDots: false,
@@ -66,7 +67,9 @@ export function* compareReqQuery(
     ) {
       const schemaId = `[root].paths.${path}.${method}.parameters[${parameterIndex}]`;
       const validate = getValidateFunction(ajv, schemaId, () =>
-        process.env.QUIRKS && value && isQuirky(schema)
+        config.get("noValidateComplexParameters") &&
+        isSimpleSchema(schema) &&
+        value
           ? {}
           : minimumSchema(schema, oas),
       );

src/compare/setup.ts

@@ -5,6 +5,7 @@ import Router, { HTTPMethod } from "find-my-way";
 import { uniqWith } from "lodash-es";
 import { cleanPathParameter } from "./utils/parameters";
 import { dereferenceOas } from "../utils/schema";
+import { config } from "../utils/config";
 
 export function setupAjv(options: Options): Ajv {
   const ajv = new Ajv(options);
@@ -31,8 +32,8 @@ export function setupRouter(
   oas: OpenAPIV2.Document | OpenAPIV3.Document,
 ): Router.Instance<Router.HTTPVersion.V1> {
   const router = Router({
-    ignoreDuplicateSlashes: process.env.QUIRKS ? true : false,
-    ignoreTrailingSlash: process.env.QUIRKS ? true : false,
+    ignoreDuplicateSlashes: config.get("duplicateSlashes"),
+    ignoreTrailingSlash: config.get("trailingSlash"),
     querystringParser: (s: string): string => s, // don't parse query in router
   });
   for (const oasPath in oas.paths) {

src/transform/responseSchema.ts

@@ -1,5 +1,6 @@
 import { SchemaObject } from "ajv";
 import { each, get } from "lodash-es";
+import { config } from "../utils/config";
 import {
   splitPath,
   traverseWithDereferencing as traverse,
@@ -17,7 +18,7 @@ export const transformResponseSchema = (schema: SchemaObject): SchemaObject => {
       !s.anyOf &&
       s.type &&
       s.type === "object" &&
-      (process.env.QUIRKS ? !s.nullable : true)
+      (config.get("noTransformNonNullableResponseSchema") ? !s.nullable : true)
     ) {
       s.additionalProperties = false;
     }

src/utils/config.ts

@@ -0,0 +1,31 @@
+const quirks = !!process.env.QUIRKS;
+
+export const config = new Map([
+  // SMV ignores duplicate slashes in OAS
+  ["ignoreDuplicateSlashes", quirks],
+
+  // SMV ignores trailing slashes in OAS
+  ["ignoreTrailingSlash", quirks],
+
+  // SMV had a bug whereby nullable response schemas were not transformed
+  // correctly. It was missing a transformation to set additionalProperties to
+  // false. This flag reproduces the bug.
+  ["noTransformNonNullableResponseSchema", quirks],
+
+  // SMV used node:querystring to parse query strings and
+  // application/x-www-form-urlencoded form bodies. This had a limitation that
+  // nested objects/arrays are not parsed correctly
+  ["legacyParser", quirks],
+
+  // SMV didn't support multipart/form-data
+  ["disableMultipartFormdata", quirks],
+
+  // SMV had a bug whereby request bodies of *any* content-type are not
+  // validated unless application/json is in the list of supported request
+  // content types
+  ["noValidateRequestBodyUnlessApplicationJson", quirks],
+
+  // SMV only validated schemas of arrays and objects in path, headers, and
+  // query params
+  ["noValidateComplexParameters", quirks],
+]);

src/utils/quirks.ts

@@ -1,4 +1,4 @@
 import type { SchemaObject } from "ajv";
 
-export const isQuirky = (s?: SchemaObject): boolean =>
+export const isSimpleSchema = (s?: SchemaObject): boolean =>
   s === undefined || s.type === "array" || s.type === "object";