1<?php 2 3namespace dokuwiki\plugin\aichat\Model; 4 5use dokuwiki\HTTP\DokuHTTPClient; 6 7/** 8 * Base class for all models 9 * 10 * Model classes also need to implement one of the following interfaces: 11 * - ChatInterface 12 * - EmbeddingInterface 13 * 14 * This class already implements most of the requirements for these interfaces. 15 * 16 * In addition to any missing interface methods, model implementations will need to 17 * extend the constructor to handle the plugin configuration and implement the 18 * parseAPIResponse() method to handle the specific API response. 19 */ 20abstract class AbstractModel implements ModelInterface 21{ 22 /** @var string The model name */ 23 protected $modelName; 24 /** @var array The model info from the model.json file */ 25 protected $modelInfo; 26 27 /** @var int input tokens used since last reset */ 28 protected $inputTokensUsed = 0; 29 /** @var int output tokens used since last reset */ 30 protected $outputTokensUsed = 0; 31 /** @var int total time spent in requests since last reset */ 32 protected $timeUsed = 0; 33 /** @var int total number of requests made since last reset */ 34 protected $requestsMade = 0; 35 /** @var int start time of the current request chain (may be multiple when retries needed) */ 36 protected $requestStart = 0; 37 38 /** @var int How often to retry a request if it fails */ 39 public const MAX_RETRIES = 3; 40 41 /** @var DokuHTTPClient */ 42 protected $http; 43 /** @var bool debug API communication */ 44 protected $debug = false; 45 46 // region ModelInterface 47 48 /** @inheritdoc */ 49 public function __construct(string $name, array $config) 50 { 51 $this->modelName = $name; 52 $this->http = new DokuHTTPClient(); 53 $this->http->timeout = 60; 54 $this->http->headers['Content-Type'] = 'application/json'; 55 56 $reflect = new \ReflectionClass($this); 57 $json = dirname($reflect->getFileName()) . '/models.json'; 58 if (!file_exists($json)) { 59 throw new \Exception('Model info file not found at ' . $json); 60 } 61 try { 62 $modelinfos = json_decode(file_get_contents($json), true, 512, JSON_THROW_ON_ERROR); 63 } catch (\JsonException $e) { 64 throw new \Exception('Failed to parse model info file: ' . $e->getMessage(), $e->getCode(), $e); 65 } 66 67 if ($this instanceof ChatInterface) { 68 if (!isset($modelinfos['chat'][$name])) { 69 throw new \Exception('Invalid chat model configured: ' . $name); 70 } 71 $this->modelInfo = $modelinfos['chat'][$name]; 72 } 73 74 if ($this instanceof EmbeddingInterface) { 75 if (!isset($modelinfos['embedding'][$name])) { 76 throw new \Exception('Invalid embedding model configured: ' . $name); 77 } 78 $this->modelInfo = $modelinfos['embedding'][$name]; 79 } 80 } 81 82 /** @inheritdoc */ 83 public function getModelName() 84 { 85 return $this->modelName; 86 } 87 88 /** 89 * Reset the usage statistics 90 * 91 * Usually not needed when only handling one operation per request, but useful in CLI 92 */ 93 public function resetUsageStats() 94 { 95 $this->tokensUsed = 0; 96 $this->timeUsed = 0; 97 $this->requestsMade = 0; 98 } 99 100 /** 101 * Get the usage statistics for this instance 102 * 103 * @return string[] 104 */ 105 public function getUsageStats() 106 { 107 108 $cost = 0; 109 $cost += $this->inputTokensUsed * $this->getInputTokenPrice(); 110 if ($this instanceof ChatInterface) { 111 $cost += $this->outputTokensUsed * $this->getOutputTokenPrice(); 112 } 113 114 return [ 115 'tokens' => $this->inputTokensUsed + $this->outputTokensUsed, 116 'cost' => round($cost / 1_000_000, 4), 117 'time' => round($this->timeUsed, 2), 118 'requests' => $this->requestsMade, 119 ]; 120 } 121 122 /** @inheritdoc */ 123 public function getMaxInputTokenLength(): int 124 { 125 return $this->modelInfo['inputTokens']; 126 } 127 128 /** @inheritdoc */ 129 public function getInputTokenPrice(): float 130 { 131 return $this->modelInfo['inputTokenPrice']; 132 } 133 134 // endregion 135 136 // region EmbeddingInterface 137 138 /** @inheritdoc */ 139 public function getDimensions(): int 140 { 141 return $this->modelInfo['dimensions']; 142 } 143 144 // endregion 145 146 // region ChatInterface 147 148 public function getMaxOutputTokenLength(): int 149 { 150 return $this->modelInfo['outputTokens']; 151 } 152 153 public function getOutputTokenPrice(): float 154 { 155 return $this->modelInfo['outputTokenPrice']; 156 } 157 158 // endregion 159 160 // region API communication 161 162 /** 163 * When enabled, the input/output of the API will be printed to STDOUT 164 * 165 * @param bool $debug 166 */ 167 public function setDebug($debug = true) 168 { 169 $this->debug = $debug; 170 } 171 172 /** 173 * This method should check the response for any errors. If the API singalled an error, 174 * this method should throw an Exception with a meaningful error message. 175 * 176 * If the response returned any info on used tokens, they should be added to $this->tokensUsed 177 * 178 * The method should return the parsed response, which will be passed to the calling method. 179 * 180 * @param mixed $response the parsed JSON response from the API 181 * @return mixed 182 * @throws \Exception when the response indicates an error 183 */ 184 abstract protected function parseAPIResponse($response); 185 186 /** 187 * Send a request to the API 188 * 189 * Model classes should use this method to send requests to the API. 190 * 191 * This method will take care of retrying and logging basic statistics. 192 * 193 * It is assumed that all APIs speak JSON. 194 * 195 * @param string $method The HTTP method to use (GET, POST, PUT, DELETE, etc.) 196 * @param string $url The full URL to send the request to 197 * @param array $data Payload to send, will be encoded to JSON 198 * @param int $retry How often this request has been retried, do not set externally 199 * @return array API response as returned by parseAPIResponse 200 * @throws \Exception when anything goes wrong 201 */ 202 protected function sendAPIRequest($method, $url, $data, $retry = 0) 203 { 204 // init statistics 205 if ($retry === 0) { 206 $this->requestStart = microtime(true); 207 } else { 208 sleep($retry); // wait a bit between retries 209 } 210 $this->requestsMade++; 211 212 // encode payload data 213 try { 214 $json = json_encode($data, JSON_THROW_ON_ERROR | JSON_PRETTY_PRINT); 215 } catch (\JsonException $e) { 216 $this->timeUsed += $this->requestStart - microtime(true); 217 throw new \Exception('Failed to encode JSON for API:' . $e->getMessage(), $e->getCode(), $e); 218 } 219 220 if ($this->debug) { 221 echo 'Sending ' . $method . ' request to ' . $url . ' with payload:' . "\n"; 222 print_r($json); 223 } 224 225 // send request and handle retries 226 $this->http->sendRequest($url, $json, $method); 227 $response = $this->http->resp_body; 228 if ($response === false || $this->http->error) { 229 if ($retry < self::MAX_RETRIES) { 230 return $this->sendAPIRequest($method, $url, $data, $retry + 1); 231 } 232 $this->timeUsed += microtime(true) - $this->requestStart; 233 throw new \Exception('API returned no response. ' . $this->http->error); 234 } 235 236 if ($this->debug) { 237 echo 'Received response:' . "\n"; 238 print_r($response); 239 } 240 241 // decode the response 242 try { 243 $result = json_decode((string)$response, true, 512, JSON_THROW_ON_ERROR); 244 } catch (\JsonException $e) { 245 $this->timeUsed += microtime(true) - $this->requestStart; 246 throw new \Exception('API returned invalid JSON: ' . $response, 0, $e); 247 } 248 249 // parse the response, retry on error 250 try { 251 $result = $this->parseAPIResponse($result); 252 } catch (\Exception $e) { 253 if ($retry < self::MAX_RETRIES) { 254 return $this->sendAPIRequest($method, $url, $data, $retry + 1); 255 } 256 $this->timeUsed += microtime(true) - $this->requestStart; 257 throw $e; 258 } 259 260 $this->timeUsed += microtime(true) - $this->requestStart; 261 return $result; 262 } 263 264 // endregion 265} 266