extracted the config directory access

src/lib/mcp-auth-config.ts

@@ -0,0 +1,146 @@
+import crypto from 'crypto'
+import path from 'path'
+import os from 'os'
+import fs from 'fs/promises'
+
+/**
+ * MCP Remote Authentication Configuration
+ * 
+ * This module handles the storage and retrieval of authentication-related data for MCP Remote.
+ * 
+ * Configuration directory structure:
+ * - The config directory is determined by MCP_REMOTE_CONFIG_DIR env var or defaults to ~/.mcp-auth
+ * - Each file is prefixed with a hash of the server URL to separate configurations for different servers
+ * 
+ * Files stored in the config directory:
+ * - {server_hash}_client_info.json: Contains OAuth client registration information
+ *   - Format: OAuthClientInformation object with client_id and other registration details
+ * - {server_hash}_tokens.json: Contains OAuth access and refresh tokens
+ *   - Format: OAuthTokens object with access_token, refresh_token, and expiration information
+ * - {server_hash}_code_verifier.txt: Contains the PKCE code verifier for the current OAuth flow
+ *   - Format: Plain text string used for PKCE verification
+ * 
+ * All JSON files are stored with 2-space indentation for readability.
+ */
+
+/**
+ * Gets the configuration directory path
+ * @returns The path to the configuration directory
+ */
+export function getConfigDir(): string {
+  return process.env.MCP_REMOTE_CONFIG_DIR || path.join(os.homedir(), '.mcp-auth')
+}
+
+/**
+ * Ensures the configuration directory exists
+ */
+export async function ensureConfigDir(): Promise<void> {
+  try {
+    const configDir = getConfigDir()
+    await fs.mkdir(configDir, { recursive: true })
+  } catch (error) {
+    console.error('Error creating config directory:', error)
+    throw error
+  }
+}
+
+/**
+ * Generates a hash for the server URL to use in filenames
+ * @param serverUrl The server URL to hash
+ * @returns The hashed server URL
+ */
+export function getServerUrlHash(serverUrl: string): string {
+  return crypto.createHash('md5').update(serverUrl).digest('hex')
+}
+
+/**
+ * Reads a JSON file and parses it with the provided schema
+ * @param serverUrlHash The hash of the server URL
+ * @param filename The name of the file to read
+ * @param schema The schema to validate against
+ * @returns The parsed file content or undefined if the file doesn't exist
+ */
+export async function readJsonFile<T>(
+  serverUrlHash: string, 
+  filename: string, 
+  schema: any
+): Promise<T | undefined> {
+  try {
+    await ensureConfigDir()
+    const configDir = getConfigDir()
+    const filePath = path.join(configDir, `${serverUrlHash}_${filename}`)
+    const content = await fs.readFile(filePath, 'utf-8')
+    return await schema.parseAsync(JSON.parse(content))
+  } catch (error) {
+    if ((error as NodeJS.ErrnoException).code === 'ENOENT') {
+      return undefined
+    }
+    return undefined
+  }
+}
+
+/**
+ * Writes a JSON object to a file
+ * @param serverUrlHash The hash of the server URL
+ * @param filename The name of the file to write
+ * @param data The data to write
+ */
+export async function writeJsonFile(
+  serverUrlHash: string, 
+  filename: string, 
+  data: any
+): Promise<void> {
+  try {
+    await ensureConfigDir()
+    const configDir = getConfigDir()
+    const filePath = path.join(configDir, `${serverUrlHash}_${filename}`)
+    await fs.writeFile(filePath, JSON.stringify(data, null, 2), 'utf-8')
+  } catch (error) {
+    console.error(`Error writing ${filename}:`, error)
+    throw error
+  }
+}
+
+/**
+ * Reads a text file
+ * @param serverUrlHash The hash of the server URL
+ * @param filename The name of the file to read
+ * @param errorMessage Optional custom error message
+ * @returns The file content as a string
+ */
+export async function readTextFile(
+  serverUrlHash: string, 
+  filename: string,
+  errorMessage?: string
+): Promise<string> {
+  try {
+    await ensureConfigDir()
+    const configDir = getConfigDir()
+    const filePath = path.join(configDir, `${serverUrlHash}_${filename}`)
+    return await fs.readFile(filePath, 'utf-8')
+  } catch (error) {
+    throw new Error(errorMessage || `Error reading ${filename}`)
+  }
+}
+
+/**
+ * Writes a text string to a file
+ * @param serverUrlHash The hash of the server URL
+ * @param filename The name of the file to write
+ * @param text The text to write
+ */
+export async function writeTextFile(
+  serverUrlHash: string, 
+  filename: string, 
+  text: string
+): Promise<void> {
+  try {
+    await ensureConfigDir()
+    const configDir = getConfigDir()
+    const filePath = path.join(configDir, `${serverUrlHash}_${filename}`)
+    await fs.writeFile(filePath, text, 'utf-8')
+  } catch (error) {
+    console.error(`Error writing ${filename}:`, error)
+    throw error
+  }
+}