anthropic_client.rs

  1use anthropic::{
  2    ANTHROPIC_API_URL, Event, Message, Request as AnthropicRequest, RequestContent,
  3    Response as AnthropicResponse, ResponseContent, Role, non_streaming_completion,
  4    stream_completion,
  5};
  6use anyhow::Result;
  7use futures::StreamExt as _;
  8use http_client::HttpClient;
  9use indoc::indoc;
 10use reqwest_client::ReqwestClient;
 11use sqlez::bindable::Bind;
 12use sqlez::bindable::StaticColumnCount;
 13use sqlez_macros::sql;
 14use std::hash::Hash;
 15use std::hash::Hasher;
 16use std::path::Path;
 17use std::sync::Arc;
 18
 19pub struct PlainLlmClient {
 20    pub http_client: Arc<dyn HttpClient>,
 21    pub api_key: String,
 22}
 23
 24impl PlainLlmClient {
 25    pub fn new() -> Result<Self> {
 26        let http_client: Arc<dyn http_client::HttpClient> = Arc::new(ReqwestClient::new());
 27        let api_key = std::env::var("ANTHROPIC_API_KEY")
 28            .map_err(|_| anyhow::anyhow!("ANTHROPIC_API_KEY environment variable not set"))?;
 29        Ok(Self {
 30            http_client,
 31            api_key,
 32        })
 33    }
 34
 35    pub async fn generate(
 36        &self,
 37        model: &str,
 38        max_tokens: u64,
 39        messages: Vec<Message>,
 40    ) -> Result<AnthropicResponse> {
 41        let request = AnthropicRequest {
 42            model: model.to_string(),
 43            max_tokens,
 44            messages,
 45            tools: Vec::new(),
 46            thinking: None,
 47            tool_choice: None,
 48            system: None,
 49            metadata: None,
 50            stop_sequences: Vec::new(),
 51            temperature: None,
 52            top_k: None,
 53            top_p: None,
 54        };
 55
 56        let response = non_streaming_completion(
 57            self.http_client.as_ref(),
 58            ANTHROPIC_API_URL,
 59            &self.api_key,
 60            request,
 61            None,
 62        )
 63        .await
 64        .map_err(|e| anyhow::anyhow!("{:?}", e))?;
 65
 66        Ok(response)
 67    }
 68
 69    pub async fn generate_streaming<F>(
 70        &self,
 71        model: &str,
 72        max_tokens: u64,
 73        messages: Vec<Message>,
 74        mut on_progress: F,
 75    ) -> Result<AnthropicResponse>
 76    where
 77        F: FnMut(usize, &str),
 78    {
 79        let request = AnthropicRequest {
 80            model: model.to_string(),
 81            max_tokens,
 82            messages,
 83            tools: Vec::new(),
 84            thinking: None,
 85            tool_choice: None,
 86            system: None,
 87            metadata: None,
 88            stop_sequences: Vec::new(),
 89            temperature: None,
 90            top_k: None,
 91            top_p: None,
 92        };
 93
 94        let mut stream = stream_completion(
 95            self.http_client.as_ref(),
 96            ANTHROPIC_API_URL,
 97            &self.api_key,
 98            request,
 99            None,
100        )
101        .await
102        .map_err(|e| anyhow::anyhow!("{:?}", e))?;
103
104        let mut response: Option<AnthropicResponse> = None;
105        let mut text_content = String::new();
106
107        while let Some(event_result) = stream.next().await {
108            let event = event_result.map_err(|e| anyhow::anyhow!("{:?}", e))?;
109
110            match event {
111                Event::MessageStart { message } => {
112                    response = Some(message);
113                }
114                Event::ContentBlockDelta { delta, .. } => {
115                    if let anthropic::ContentDelta::TextDelta { text } = delta {
116                        text_content.push_str(&text);
117                        on_progress(text_content.len(), &text_content);
118                    }
119                }
120                _ => {}
121            }
122        }
123
124        let mut response = response.ok_or_else(|| anyhow::anyhow!("No response received"))?;
125
126        if response.content.is_empty() && !text_content.is_empty() {
127            response
128                .content
129                .push(ResponseContent::Text { text: text_content });
130        }
131
132        Ok(response)
133    }
134}
135
136pub struct BatchingLlmClient {
137    connection: sqlez::connection::Connection,
138    http_client: Arc<dyn HttpClient>,
139    api_key: String,
140}
141
142struct CacheRow {
143    request_hash: String,
144    request: Option<String>,
145    response: Option<String>,
146    batch_id: Option<String>,
147}
148
149impl StaticColumnCount for CacheRow {
150    fn column_count() -> usize {
151        4
152    }
153}
154
155impl Bind for CacheRow {
156    fn bind(&self, statement: &sqlez::statement::Statement, start_index: i32) -> Result<i32> {
157        let next_index = statement.bind(&self.request_hash, start_index)?;
158        let next_index = statement.bind(&self.request, next_index)?;
159        let next_index = statement.bind(&self.response, next_index)?;
160        let next_index = statement.bind(&self.batch_id, next_index)?;
161        Ok(next_index)
162    }
163}
164
165#[derive(serde::Serialize, serde::Deserialize)]
166struct SerializableRequest {
167    model: String,
168    max_tokens: u64,
169    messages: Vec<SerializableMessage>,
170}
171
172#[derive(serde::Serialize, serde::Deserialize)]
173struct SerializableMessage {
174    role: String,
175    content: String,
176}
177
178impl BatchingLlmClient {
179    fn new(cache_path: &Path) -> Result<Self> {
180        let http_client: Arc<dyn http_client::HttpClient> = Arc::new(ReqwestClient::new());
181        let api_key = std::env::var("ANTHROPIC_API_KEY")
182            .map_err(|_| anyhow::anyhow!("ANTHROPIC_API_KEY environment variable not set"))?;
183
184        let connection = sqlez::connection::Connection::open_file(&cache_path.to_str().unwrap());
185        let mut statement = sqlez::statement::Statement::prepare(
186            &connection,
187            indoc! {"
188                CREATE TABLE IF NOT EXISTS cache (
189                    request_hash TEXT PRIMARY KEY,
190                    request TEXT,
191                    response TEXT,
192                    batch_id TEXT
193                );
194                "},
195        )?;
196        statement.exec()?;
197        drop(statement);
198
199        Ok(Self {
200            connection,
201            http_client,
202            api_key,
203        })
204    }
205
206    pub fn lookup(
207        &self,
208        model: &str,
209        max_tokens: u64,
210        messages: &[Message],
211    ) -> Result<Option<AnthropicResponse>> {
212        let request_hash_str = Self::request_hash(model, max_tokens, messages);
213        let response: Vec<String> = self.connection.select_bound(
214            &sql!(SELECT response FROM cache WHERE request_hash = ?1 AND response IS NOT NULL;),
215        )?(request_hash_str.as_str())?;
216        Ok(response
217            .into_iter()
218            .next()
219            .and_then(|text| serde_json::from_str(&text).ok()))
220    }
221
222    pub fn mark_for_batch(&self, model: &str, max_tokens: u64, messages: &[Message]) -> Result<()> {
223        let request_hash = Self::request_hash(model, max_tokens, messages);
224
225        let serializable_messages: Vec<SerializableMessage> = messages
226            .iter()
227            .map(|msg| SerializableMessage {
228                role: match msg.role {
229                    Role::User => "user".to_string(),
230                    Role::Assistant => "assistant".to_string(),
231                },
232                content: message_content_to_string(&msg.content),
233            })
234            .collect();
235
236        let serializable_request = SerializableRequest {
237            model: model.to_string(),
238            max_tokens,
239            messages: serializable_messages,
240        };
241
242        let request = Some(serde_json::to_string(&serializable_request)?);
243        let cache_row = CacheRow {
244            request_hash,
245            request,
246            response: None,
247            batch_id: None,
248        };
249        self.connection.exec_bound(sql!(
250            INSERT OR IGNORE INTO cache(request_hash, request, response, batch_id) VALUES (?, ?, ?, ?)))?(
251            cache_row,
252        )
253    }
254
255    async fn generate(
256        &self,
257        model: &str,
258        max_tokens: u64,
259        messages: Vec<Message>,
260    ) -> Result<Option<AnthropicResponse>> {
261        let response = self.lookup(model, max_tokens, &messages)?;
262        if let Some(response) = response {
263            return Ok(Some(response));
264        }
265
266        self.mark_for_batch(model, max_tokens, &messages)?;
267
268        Ok(None)
269    }
270
271    /// Uploads pending requests as a new batch; downloads finished batches if any.
272    async fn sync_batches(&self) -> Result<()> {
273        self.upload_pending_requests().await?;
274        self.download_finished_batches().await
275    }
276
277    async fn download_finished_batches(&self) -> Result<()> {
278        let q = sql!(SELECT DISTINCT batch_id FROM cache WHERE batch_id IS NOT NULL AND response IS NULL);
279        let batch_ids: Vec<String> = self.connection.select(q)?()?;
280
281        for batch_id in batch_ids {
282            let batch_status = anthropic::batches::retrieve_batch(
283                self.http_client.as_ref(),
284                ANTHROPIC_API_URL,
285                &self.api_key,
286                &batch_id,
287            )
288            .await
289            .map_err(|e| anyhow::anyhow!("{:?}", e))?;
290
291            log::info!(
292                "Batch {} status: {}",
293                batch_id,
294                batch_status.processing_status
295            );
296
297            if batch_status.processing_status == "ended" {
298                let results = anthropic::batches::retrieve_batch_results(
299                    self.http_client.as_ref(),
300                    ANTHROPIC_API_URL,
301                    &self.api_key,
302                    &batch_id,
303                )
304                .await
305                .map_err(|e| anyhow::anyhow!("{:?}", e))?;
306
307                let mut success_count = 0;
308                for result in results {
309                    let request_hash = result
310                        .custom_id
311                        .strip_prefix("req_hash_")
312                        .unwrap_or(&result.custom_id)
313                        .to_string();
314
315                    match result.result {
316                        anthropic::batches::BatchResult::Succeeded { message } => {
317                            let response_json = serde_json::to_string(&message)?;
318                            let q = sql!(UPDATE cache SET response = ? WHERE request_hash = ?);
319                            self.connection.exec_bound(q)?((response_json, request_hash))?;
320                            success_count += 1;
321                        }
322                        anthropic::batches::BatchResult::Errored { error } => {
323                            log::error!("Batch request {} failed: {:?}", request_hash, error);
324                        }
325                        anthropic::batches::BatchResult::Canceled => {
326                            log::warn!("Batch request {} was canceled", request_hash);
327                        }
328                        anthropic::batches::BatchResult::Expired => {
329                            log::warn!("Batch request {} expired", request_hash);
330                        }
331                    }
332                }
333                log::info!("Downloaded {} successful requests", success_count);
334            }
335        }
336
337        Ok(())
338    }
339
340    async fn upload_pending_requests(&self) -> Result<String> {
341        let q = sql!(
342        SELECT request_hash, request FROM cache WHERE batch_id IS NULL AND response IS NULL
343        );
344
345        let rows: Vec<(String, String)> = self.connection.select(q)?()?;
346
347        if rows.is_empty() {
348            return Ok(String::new());
349        }
350
351        let batch_requests = rows
352            .iter()
353            .map(|(hash, request_str)| {
354                let serializable_request: SerializableRequest =
355                    serde_json::from_str(&request_str).unwrap();
356
357                let messages: Vec<Message> = serializable_request
358                    .messages
359                    .into_iter()
360                    .map(|msg| Message {
361                        role: match msg.role.as_str() {
362                            "user" => Role::User,
363                            "assistant" => Role::Assistant,
364                            _ => Role::User,
365                        },
366                        content: vec![RequestContent::Text {
367                            text: msg.content,
368                            cache_control: None,
369                        }],
370                    })
371                    .collect();
372
373                let params = AnthropicRequest {
374                    model: serializable_request.model,
375                    max_tokens: serializable_request.max_tokens,
376                    messages,
377                    tools: Vec::new(),
378                    thinking: None,
379                    tool_choice: None,
380                    system: None,
381                    metadata: None,
382                    stop_sequences: Vec::new(),
383                    temperature: None,
384                    top_k: None,
385                    top_p: None,
386                };
387
388                let custom_id = format!("req_hash_{}", hash);
389                anthropic::batches::BatchRequest { custom_id, params }
390            })
391            .collect::<Vec<_>>();
392
393        let batch_len = batch_requests.len();
394        let batch = anthropic::batches::create_batch(
395            self.http_client.as_ref(),
396            ANTHROPIC_API_URL,
397            &self.api_key,
398            anthropic::batches::CreateBatchRequest {
399                requests: batch_requests,
400            },
401        )
402        .await
403        .map_err(|e| anyhow::anyhow!("{:?}", e))?;
404
405        let q = sql!(
406            UPDATE cache SET batch_id = ? WHERE batch_id is NULL
407        );
408        self.connection.exec_bound(q)?(batch.id.as_str())?;
409
410        log::info!("Uploaded batch with {} requests", batch_len);
411
412        Ok(batch.id)
413    }
414
415    fn request_hash(model: &str, max_tokens: u64, messages: &[Message]) -> String {
416        let mut hasher = std::hash::DefaultHasher::new();
417        model.hash(&mut hasher);
418        max_tokens.hash(&mut hasher);
419        for msg in messages {
420            message_content_to_string(&msg.content).hash(&mut hasher);
421        }
422        let request_hash = hasher.finish();
423        format!("{request_hash:016x}")
424    }
425}
426
427fn message_content_to_string(content: &[RequestContent]) -> String {
428    content
429        .iter()
430        .filter_map(|c| match c {
431            RequestContent::Text { text, .. } => Some(text.clone()),
432            _ => None,
433        })
434        .collect::<Vec<String>>()
435        .join("\n")
436}
437
438pub enum AnthropicClient {
439    // No batching
440    Plain(PlainLlmClient),
441    Batch(BatchingLlmClient),
442    Dummy,
443}
444
445impl AnthropicClient {
446    pub fn plain() -> Result<Self> {
447        Ok(Self::Plain(PlainLlmClient::new()?))
448    }
449
450    pub fn batch(cache_path: &Path) -> Result<Self> {
451        Ok(Self::Batch(BatchingLlmClient::new(cache_path)?))
452    }
453
454    #[allow(dead_code)]
455    pub fn dummy() -> Self {
456        Self::Dummy
457    }
458
459    pub async fn generate(
460        &self,
461        model: &str,
462        max_tokens: u64,
463        messages: Vec<Message>,
464    ) -> Result<Option<AnthropicResponse>> {
465        match self {
466            AnthropicClient::Plain(plain_llm_client) => plain_llm_client
467                .generate(model, max_tokens, messages)
468                .await
469                .map(Some),
470            AnthropicClient::Batch(batching_llm_client) => {
471                batching_llm_client
472                    .generate(model, max_tokens, messages)
473                    .await
474            }
475            AnthropicClient::Dummy => panic!("Dummy LLM client is not expected to be used"),
476        }
477    }
478
479    #[allow(dead_code)]
480    pub async fn generate_streaming<F>(
481        &self,
482        model: &str,
483        max_tokens: u64,
484        messages: Vec<Message>,
485        on_progress: F,
486    ) -> Result<Option<AnthropicResponse>>
487    where
488        F: FnMut(usize, &str),
489    {
490        match self {
491            AnthropicClient::Plain(plain_llm_client) => plain_llm_client
492                .generate_streaming(model, max_tokens, messages, on_progress)
493                .await
494                .map(Some),
495            AnthropicClient::Batch(_) => {
496                anyhow::bail!("Streaming not supported with batching client")
497            }
498            AnthropicClient::Dummy => panic!("Dummy LLM client is not expected to be used"),
499        }
500    }
501
502    pub async fn sync_batches(&self) -> Result<()> {
503        match self {
504            AnthropicClient::Plain(_) => Ok(()),
505            AnthropicClient::Batch(batching_llm_client) => batching_llm_client.sync_batches().await,
506            AnthropicClient::Dummy => panic!("Dummy LLM client is not expected to be used"),
507        }
508    }
509}