Add ability to override protocol from http:// to file:// in schema ids

src/cli.ts

@@ -15,6 +15,7 @@ main(
       help: ['h'],
       input: ['i'],
       output: ['o'],
+      overrideHttpId: ['m'],
     },
     boolean: [
       'additionalProperties',
@@ -40,6 +41,8 @@ async function main(argv: minimist.ParsedArgs) {
   const argIn: string = argv._[0] || argv.input
   const argOut: string | undefined = argv._[1] || argv.output // the output can be omitted so this can be undefined
 
+  const overrideHttpId: {[key: string]: string} = parseOverrideHttpIdArgs(argv.overrideHttpId)
+
   const ISGLOB = isGlob(argIn)
   const ISDIR = isDir(argIn)
 
@@ -52,11 +55,11 @@ async function main(argv: minimist.ParsedArgs) {
   try {
     // Process input as either glob, directory, or single file
     if (ISGLOB) {
-      await processGlob(argIn, argOut, argv as Partial<Options>)
+      await processGlob(argIn, argOut, {...argv, overrideHttpId} as Partial<Options>)
     } else if (ISDIR) {
-      await processDir(argIn, argOut, argv as Partial<Options>)
+      await processDir(argIn, argOut, {...argv, overrideHttpId} as Partial<Options>)
     } else {
-      const result = await processFile(argIn, argv as Partial<Options>)
+      const result = await processFile(argIn, {...argv, overrideHttpId} as Partial<Options>)
       outputResult(result, argOut)
     }
   } catch (e) {
@@ -160,6 +163,19 @@ async function readStream(stream: NodeJS.ReadStream): Promise<string> {
   return Buffer.concat(chunks).toString('utf8')
 }
 
+function parseOverrideHttpIdArgs(overrideHttpId: any) {
+  const overrideHttpIdArg: {[key: string]: string} =
+    typeof overrideHttpId === 'string' ? {'0': overrideHttpId} : overrideHttpId
+  const result: {[key: string]: string} = {}
+  if (overrideHttpIdArg !== null) {
+    for (const [, value] of Object.entries(overrideHttpIdArg)) {
+      const [originalSchemaUrl, overrideSchemaUrl] = value.split(' ')
+      result[originalSchemaUrl] = overrideSchemaUrl
+    }
+  }
+  return Object.freeze(result)
+}
+
 function printHelp() {
   const pkg = require('../../package.json')
 
@@ -192,6 +208,12 @@ Boolean values can be set to false using the 'no-' prefix.
       array types, before falling back to emitting unbounded arrays. Increase
       this to improve precision of emitted types, decrease it to improve
       performance, or set it to -1 to ignore minItems and maxItems.
+  --overrideHttpId
+      Define overrides for HTTP schema ids to map it to file system.
+      --overrideHttpId=http://schemas.example.org/ file:///home/me/my-project/src/schemas/
+      or
+      --overrideHttpId.1=http://schemas1.example.org/ file:///home/me/my-project1/src/schemas/
+      --overrideHttpId.2=http://schemas2.example.org/ file:///home/me/my-project2/src/schemas/
   --style.XXX=YYY
       Prettier configuration
   --unknownAny

src/index.ts

@@ -48,6 +48,16 @@ export interface Options {
    * Prepend enums with [`const`](https://www.typescriptlang.org/docs/handbook/enums.html#computed-and-constant-members)?
    */
   enableConstEnums: boolean
+  /**
+   * Define overrides for HTTP schema ids to map it to file system.
+   *
+   * @example
+   * {
+   *    "http://schemas1.example.org/": "file:///home/me/my-project1/src/schemas/",
+   *    "http://schemas2.example.org/": "file:///home/me/my-project2/src/schemas/"
+   * }
+   */
+  overrideHttpId: {[key: string]: string} | null
   /**
    * Create enums from JSON enums with eponymous keys
    */
@@ -101,6 +111,7 @@ export const DEFAULT_OPTIONS: Options = {
   enableConstEnums: true,
   inferStringEnumKeysFromValues: false,
   format: true,
+  overrideHttpId: null,
   ignoreMinAndMaxItems: false,
   maxItems: 20,
   strictIndexSignatures: false,

src/resolver.ts

@@ -1,15 +1,26 @@
-import {$RefParser, ParserOptions as $RefOptions} from '@apidevtools/json-schema-ref-parser'
+import {readFile} from 'fs/promises'
+import {
+  $RefParser,
+  ParserOptions as $RefOptions,
+  HTTPResolverOptions,
+  FileInfo,
+} from '@apidevtools/json-schema-ref-parser'
 import {JSONSchema} from './types/JSONSchema'
 import {log} from './utils'
 
 export type DereferencedPaths = WeakMap<JSONSchema, string>
 
 export async function dereference(
   schema: JSONSchema,
-  {cwd, $refOptions}: {cwd: string; $refOptions: $RefOptions},
+  {
+    cwd,
+    $refOptions,
+    overrideHttpId,
+  }: {cwd: string; overrideHttpId: {[key: string]: string} | null; $refOptions: $RefOptions},
 ): Promise<{dereferencedPaths: DereferencedPaths; dereferencedSchema: JSONSchema}> {
   log('green', 'dereferencer', 'Dereferencing input schema:', cwd, schema)
   const parser = new $RefParser()
+  const myResolver = new MyResolver(overrideHttpId)
   const dereferencedPaths: DereferencedPaths = new WeakMap()
   const dereferencedSchema = (await parser.dereference(cwd, schema, {
     ...$refOptions,
@@ -19,6 +30,61 @@ export async function dereference(
         dereferencedPaths.set(schema, $ref)
       },
     },
+    resolve: {
+      httpOverride: {
+        order: 1,
+        canRead(file: FileInfo) {
+          return myResolver.canRead(file)
+        },
+        read(file: FileInfo) {
+          return myResolver.read(file)
+        },
+      },
+    },
   })) as any // TODO: fix types
   return {dereferencedPaths, dereferencedSchema}
 }
+
+class MyResolver implements HTTPResolverOptions {
+  private readonly overrideHttpId: ReadonlyArray<{originalSchemaUrl: URL; overrideSchemaUrl: URL}> | null
+
+  public constructor(overrideHttpId: {[key: string]: string} | null) {
+    if (overrideHttpId !== null) {
+      const result: Array<{originalSchemaUrl: URL; overrideSchemaUrl: URL}> = []
+      for (const [originalSchemaUrl, overrideSchemaUrl] of Object.entries(overrideHttpId)) {
+        result.push({originalSchemaUrl: new URL(originalSchemaUrl), overrideSchemaUrl: new URL(overrideSchemaUrl)})
+      }
+      this.overrideHttpId = Object.freeze(result)
+    } else {
+      this.overrideHttpId = null
+    }
+  }
+
+  public canRead(file: FileInfo): boolean {
+    if (this.overrideHttpId !== null) {
+      for (const {originalSchemaUrl} of this.overrideHttpId) {
+        const originalSchemaUrlStr: string = originalSchemaUrl.toString()
+        if (file.url.startsWith(originalSchemaUrlStr)) {
+          return true
+        }
+      }
+    }
+    return false
+  }
+
+  public async read(file: FileInfo): Promise<string | Buffer> {
+    if (this.overrideHttpId !== null) {
+      for (const {originalSchemaUrl, overrideSchemaUrl} of this.overrideHttpId) {
+        const originalSchemaUrlStr: string = originalSchemaUrl.toString()
+        if (file.url.startsWith(originalSchemaUrlStr)) {
+          const overrideSchemaUrlStr: string = overrideSchemaUrl.toString()
+          const newUrl: URL = new URL(file.url.replace(originalSchemaUrlStr, overrideSchemaUrlStr))
+          const fileData = await readFile(newUrl)
+          return fileData
+        }
+      }
+    }
+
+    throw new Error('Шось пішло не так')
+  }
+}