| 61 | 61 | const API_XAI = 'https://api.x.ai/v1'; |
| 62 | 62 | const API_POLLINATIONS = 'https://text.pollinations.ai/openai'; |
| 63 | 63 | |
| 64 | | -/** |
| 65 | | - * Generates a JWT token for Google Cloud authentication using service account credentials. |
| 66 | | - * @param {object} serviceAccount Service account JSON object |
| 67 | | - * @returns {Promise<string>} JWT token |
| 68 | | - */ |
| 69 | | -async function generateJWTToken(serviceAccount) { |
| 70 | | - const now = Math.floor(Date.now() / 1000); |
| 71 | | - const expiry = now + 3600; // 1 hour |
| 72 | | - |
| 73 | | - const header = { |
| 74 | | - alg: 'RS256', |
| 75 | | - typ: 'JWT', |
| 76 | | - }; |
| 77 | | - |
| 78 | | - const payload = { |
| 79 | | - iss: serviceAccount.client_email, |
| 80 | | - scope: 'https://www.googleapis.com/auth/cloud-platform', |
| 81 | | - aud: 'https://oauth2.googleapis.com/token', |
| 82 | | - iat: now, |
| 83 | | - exp: expiry, |
| 84 | | - }; |
| 85 | | - |
| 86 | | - const headerBase64 = Buffer.from(JSON.stringify(header)).toString('base64url'); |
| 87 | | - const payloadBase64 = Buffer.from(JSON.stringify(payload)).toString('base64url'); |
| 88 | | - const signatureInput = `${headerBase64}.${payloadBase64}`; |
| 89 | | - |
| 90 | | - // Create signature using private key |
| 91 | | - const sign = crypto.createSign('RSA-SHA256'); |
| 92 | | - sign.update(signatureInput); |
| 93 | | - const signature = sign.sign(serviceAccount.private_key, 'base64url'); |
| 94 | | - |
| 95 | | - return `${signatureInput}.${signature}`; |
| 96 | | -} |
| 97 | | - |
| 98 | | -/** |
| 99 | | - * Gets an access token from Google OAuth2 using JWT assertion. |
| 100 | | - * @param {string} jwtToken JWT token |
| 101 | | - * @returns {Promise<string>} Access token |
| 102 | | - */ |
| 103 | | -async function getAccessToken(jwtToken) { |
| 104 | | - const response = await fetch('https://oauth2.googleapis.com/token', { |
| 105 | | - method: 'POST', |
| 106 | | - headers: { |
| 107 | | - 'Content-Type': 'application/x-www-form-urlencoded', |
| 108 | | - }, |
| 109 | | - body: new URLSearchParams({ |
| 110 | | - grant_type: 'urn:ietf:params:oauth:grant-type:jwt-bearer', |
| 111 | | - assertion: jwtToken, |
| 112 | | - }), |
| 113 | | - }); |
| 114 | | - |
| 115 | | - if (!response.ok) { |
| 116 | | - throw new Error(`Failed to get access token: ${response.status} ${response.statusText}`); |
| 117 | | - } |
| 118 | | - |
| 119 | | - const data = await response.json(); |
| 120 | | - return data.access_token; |
| 121 | | -} |
| 122 | | - |
| 123 | | -/** |
| 124 | | - * Gets authentication for Vertex AI - either API key or service account token. |
| 125 | | - * @param {object} request Express request |
| 126 | | - * @returns {Promise<{authHeader: string, authType: string}>} Authentication header and type |
| 127 | | - */ |
| 128 | | -async function getVertexAIAuth(request) { |
| 129 | | - // Get the authentication mode from frontend |
| 130 | | - const authMode = request.body.vertexai_auth_mode || 'express'; |
| 131 | | - |
| 132 | | - // Check if using reverse proxy |
| 133 | | - if (request.body.reverse_proxy) { |
| 134 | | - return { |
| 135 | | - authHeader: `Bearer ${request.body.proxy_password}`, |
| 136 | | - authType: 'proxy', |
| 137 | | - }; |
| 138 | | - } |
| 139 | | - |
| 140 | | - if (authMode === 'express') { |
| 141 | | - // Express mode: use API key |
| 142 | | - const apiKey = readSecret(request.user.directories, SECRET_KEYS.VERTEXAI); |
| 143 | | - if (apiKey) { |
| 144 | | - return { |
| 145 | | - authHeader: `Bearer ${apiKey}`, |
| 146 | | - authType: 'express', |
| 147 | | - }; |
| 148 | | - } |
| 149 | | - throw new Error('API key is required for Vertex AI Express mode'); |
| 150 | | - } else if (authMode === 'full') { |
| 151 | | - // Full mode: use service account JSON |
| 152 | | - // First try to read from backend secret storage |
| 153 | | - let serviceAccountJson = readSecret(request.user.directories, SECRET_KEYS.VERTEXAI_SERVICE_ACCOUNT); |
| 154 | 64 | |
| 155 | | - // If not found in secrets, fall back to request body (for backward compatibility) |
| 156 | | - if (!serviceAccountJson) { |
| 157 | | - serviceAccountJson = request.body.vertexai_service_account_json; |
| 158 | | - } |
| 159 | 65 | |
| 160 | | - if (serviceAccountJson) { |
| 161 | | - try { |
| 162 | | - const serviceAccount = JSON.parse(serviceAccountJson); |
| 163 | 66 | |
| 164 | | - const jwtToken = await generateJWTToken(serviceAccount); |
| 165 | | - const accessToken = await getAccessToken(jwtToken); |
| 166 | 67 | |
| 167 | | - return { |
| 168 | | - authHeader: `Bearer ${accessToken}`, |
| 169 | | - authType: 'full', |
| 170 | | - }; |
| 171 | | - } catch (error) { |
| 172 | | - console.error('Failed to authenticate with service account:', error); |
| 173 | | - throw new Error(`Service account authentication failed: ${error.message}`); |
| 174 | | - } |
| 175 | | - } |
| 176 | | - throw new Error('Service Account JSON is required for Vertex AI Full mode'); |
| 177 | | - } |
| 178 | 68 | |
| 179 | | - throw new Error(`Unsupported Vertex AI authentication mode: ${authMode}`); |
| 180 | | -} |
| 181 | 69 | |
| 182 | 70 | /** |
| 183 | 71 | * Applies a post-processing step to the generated messages. |