google_ai.rs

  1use std::mem;
  2
  3use anyhow::{Result, anyhow, bail};
  4use futures::{AsyncBufReadExt, AsyncReadExt, StreamExt, io::BufReader, stream::BoxStream};
  5use http_client::{AsyncBody, HttpClient, Method, Request as HttpRequest};
  6use serde::{Deserialize, Deserializer, Serialize, Serializer};
  7
  8pub const API_URL: &str = "https://generativelanguage.googleapis.com";
  9
 10pub async fn stream_generate_content(
 11    client: &dyn HttpClient,
 12    api_url: &str,
 13    api_key: &str,
 14    mut request: GenerateContentRequest,
 15) -> Result<BoxStream<'static, Result<GenerateContentResponse>>> {
 16    validate_generate_content_request(&request)?;
 17
 18    // The `model` field is emptied as it is provided as a path parameter.
 19    let model_id = mem::take(&mut request.model.model_id);
 20
 21    let uri =
 22        format!("{api_url}/v1beta/models/{model_id}:streamGenerateContent?alt=sse&key={api_key}",);
 23
 24    let request_builder = HttpRequest::builder()
 25        .method(Method::POST)
 26        .uri(uri)
 27        .header("Content-Type", "application/json");
 28
 29    let request = request_builder.body(AsyncBody::from(serde_json::to_string(&request)?))?;
 30    let mut response = client.send(request).await?;
 31    if response.status().is_success() {
 32        let reader = BufReader::new(response.into_body());
 33        Ok(reader
 34            .lines()
 35            .filter_map(|line| async move {
 36                match line {
 37                    Ok(line) => {
 38                        if let Some(line) = line.strip_prefix("data: ") {
 39                            match serde_json::from_str(line) {
 40                                Ok(response) => Some(Ok(response)),
 41                                Err(error) => Some(Err(anyhow!(format!(
 42                                    "Error parsing JSON: {error:?}\n{line:?}"
 43                                )))),
 44                            }
 45                        } else {
 46                            None
 47                        }
 48                    }
 49                    Err(error) => Some(Err(anyhow!(error))),
 50                }
 51            })
 52            .boxed())
 53    } else {
 54        let mut text = String::new();
 55        response.body_mut().read_to_string(&mut text).await?;
 56        Err(anyhow!(
 57            "error during streamGenerateContent, status code: {:?}, body: {}",
 58            response.status(),
 59            text
 60        ))
 61    }
 62}
 63
 64pub async fn count_tokens(
 65    client: &dyn HttpClient,
 66    api_url: &str,
 67    api_key: &str,
 68    request: CountTokensRequest,
 69) -> Result<CountTokensResponse> {
 70    validate_generate_content_request(&request.generate_content_request)?;
 71
 72    let uri = format!(
 73        "{api_url}/v1beta/models/{model_id}:countTokens?key={api_key}",
 74        model_id = &request.generate_content_request.model.model_id,
 75    );
 76
 77    let request = serde_json::to_string(&request)?;
 78    let request_builder = HttpRequest::builder()
 79        .method(Method::POST)
 80        .uri(&uri)
 81        .header("Content-Type", "application/json");
 82    let http_request = request_builder.body(AsyncBody::from(request))?;
 83
 84    let mut response = client.send(http_request).await?;
 85    let mut text = String::new();
 86    response.body_mut().read_to_string(&mut text).await?;
 87    anyhow::ensure!(
 88        response.status().is_success(),
 89        "error during countTokens, status code: {:?}, body: {}",
 90        response.status(),
 91        text
 92    );
 93    Ok(serde_json::from_str::<CountTokensResponse>(&text)?)
 94}
 95
 96pub fn validate_generate_content_request(request: &GenerateContentRequest) -> Result<()> {
 97    if request.model.is_empty() {
 98        bail!("Model must be specified");
 99    }
100
101    if request.contents.is_empty() {
102        bail!("Request must contain at least one content item");
103    }
104
105    if let Some(user_content) = request
106        .contents
107        .iter()
108        .find(|content| content.role == Role::User)
109    {
110        if user_content.parts.is_empty() {
111            bail!("User content must contain at least one part");
112        }
113    }
114
115    Ok(())
116}
117
118#[derive(Debug, Serialize, Deserialize)]
119pub enum Task {
120    #[serde(rename = "generateContent")]
121    GenerateContent,
122    #[serde(rename = "streamGenerateContent")]
123    StreamGenerateContent,
124    #[serde(rename = "countTokens")]
125    CountTokens,
126    #[serde(rename = "embedContent")]
127    EmbedContent,
128    #[serde(rename = "batchEmbedContents")]
129    BatchEmbedContents,
130}
131
132#[derive(Debug, Serialize, Deserialize)]
133#[serde(rename_all = "camelCase")]
134pub struct GenerateContentRequest {
135    #[serde(default, skip_serializing_if = "ModelName::is_empty")]
136    pub model: ModelName,
137    pub contents: Vec<Content>,
138    #[serde(skip_serializing_if = "Option::is_none")]
139    pub system_instruction: Option<SystemInstruction>,
140    #[serde(skip_serializing_if = "Option::is_none")]
141    pub generation_config: Option<GenerationConfig>,
142    #[serde(skip_serializing_if = "Option::is_none")]
143    pub safety_settings: Option<Vec<SafetySetting>>,
144    #[serde(skip_serializing_if = "Option::is_none")]
145    pub tools: Option<Vec<Tool>>,
146    #[serde(skip_serializing_if = "Option::is_none")]
147    pub tool_config: Option<ToolConfig>,
148}
149
150#[derive(Debug, Serialize, Deserialize)]
151#[serde(rename_all = "camelCase")]
152pub struct GenerateContentResponse {
153    #[serde(skip_serializing_if = "Option::is_none")]
154    pub candidates: Option<Vec<GenerateContentCandidate>>,
155    #[serde(skip_serializing_if = "Option::is_none")]
156    pub prompt_feedback: Option<PromptFeedback>,
157    #[serde(skip_serializing_if = "Option::is_none")]
158    pub usage_metadata: Option<UsageMetadata>,
159}
160
161#[derive(Debug, Serialize, Deserialize)]
162#[serde(rename_all = "camelCase")]
163pub struct GenerateContentCandidate {
164    #[serde(skip_serializing_if = "Option::is_none")]
165    pub index: Option<usize>,
166    pub content: Content,
167    #[serde(skip_serializing_if = "Option::is_none")]
168    pub finish_reason: Option<String>,
169    #[serde(skip_serializing_if = "Option::is_none")]
170    pub finish_message: Option<String>,
171    #[serde(skip_serializing_if = "Option::is_none")]
172    pub safety_ratings: Option<Vec<SafetyRating>>,
173    #[serde(skip_serializing_if = "Option::is_none")]
174    pub citation_metadata: Option<CitationMetadata>,
175}
176
177#[derive(Debug, Serialize, Deserialize)]
178#[serde(rename_all = "camelCase")]
179pub struct Content {
180    #[serde(default)]
181    pub parts: Vec<Part>,
182    pub role: Role,
183}
184
185#[derive(Debug, Serialize, Deserialize)]
186#[serde(rename_all = "camelCase")]
187pub struct SystemInstruction {
188    pub parts: Vec<Part>,
189}
190
191#[derive(Debug, PartialEq, Deserialize, Serialize)]
192#[serde(rename_all = "camelCase")]
193pub enum Role {
194    User,
195    Model,
196}
197
198#[derive(Debug, Serialize, Deserialize)]
199#[serde(untagged)]
200pub enum Part {
201    TextPart(TextPart),
202    InlineDataPart(InlineDataPart),
203    FunctionCallPart(FunctionCallPart),
204    FunctionResponsePart(FunctionResponsePart),
205}
206
207#[derive(Debug, Serialize, Deserialize)]
208#[serde(rename_all = "camelCase")]
209pub struct TextPart {
210    pub text: String,
211}
212
213#[derive(Debug, Serialize, Deserialize)]
214#[serde(rename_all = "camelCase")]
215pub struct InlineDataPart {
216    pub inline_data: GenerativeContentBlob,
217}
218
219#[derive(Debug, Serialize, Deserialize)]
220#[serde(rename_all = "camelCase")]
221pub struct GenerativeContentBlob {
222    pub mime_type: String,
223    pub data: String,
224}
225
226#[derive(Debug, Serialize, Deserialize)]
227#[serde(rename_all = "camelCase")]
228pub struct FunctionCallPart {
229    pub function_call: FunctionCall,
230}
231
232#[derive(Debug, Serialize, Deserialize)]
233#[serde(rename_all = "camelCase")]
234pub struct FunctionResponsePart {
235    pub function_response: FunctionResponse,
236}
237
238#[derive(Debug, Serialize, Deserialize)]
239#[serde(rename_all = "camelCase")]
240pub struct CitationSource {
241    #[serde(skip_serializing_if = "Option::is_none")]
242    pub start_index: Option<usize>,
243    #[serde(skip_serializing_if = "Option::is_none")]
244    pub end_index: Option<usize>,
245    #[serde(skip_serializing_if = "Option::is_none")]
246    pub uri: Option<String>,
247    #[serde(skip_serializing_if = "Option::is_none")]
248    pub license: Option<String>,
249}
250
251#[derive(Debug, Serialize, Deserialize)]
252#[serde(rename_all = "camelCase")]
253pub struct CitationMetadata {
254    pub citation_sources: Vec<CitationSource>,
255}
256
257#[derive(Debug, Serialize, Deserialize)]
258#[serde(rename_all = "camelCase")]
259pub struct PromptFeedback {
260    #[serde(skip_serializing_if = "Option::is_none")]
261    pub block_reason: Option<String>,
262    pub safety_ratings: Vec<SafetyRating>,
263    #[serde(skip_serializing_if = "Option::is_none")]
264    pub block_reason_message: Option<String>,
265}
266
267#[derive(Debug, Serialize, Deserialize, Default)]
268#[serde(rename_all = "camelCase")]
269pub struct UsageMetadata {
270    #[serde(skip_serializing_if = "Option::is_none")]
271    pub prompt_token_count: Option<usize>,
272    #[serde(skip_serializing_if = "Option::is_none")]
273    pub cached_content_token_count: Option<usize>,
274    #[serde(skip_serializing_if = "Option::is_none")]
275    pub candidates_token_count: Option<usize>,
276    #[serde(skip_serializing_if = "Option::is_none")]
277    pub tool_use_prompt_token_count: Option<usize>,
278    #[serde(skip_serializing_if = "Option::is_none")]
279    pub thoughts_token_count: Option<usize>,
280    #[serde(skip_serializing_if = "Option::is_none")]
281    pub total_token_count: Option<usize>,
282}
283
284#[derive(Debug, Deserialize, Serialize)]
285#[serde(rename_all = "camelCase")]
286pub struct GenerationConfig {
287    #[serde(skip_serializing_if = "Option::is_none")]
288    pub candidate_count: Option<usize>,
289    #[serde(skip_serializing_if = "Option::is_none")]
290    pub stop_sequences: Option<Vec<String>>,
291    #[serde(skip_serializing_if = "Option::is_none")]
292    pub max_output_tokens: Option<usize>,
293    #[serde(skip_serializing_if = "Option::is_none")]
294    pub temperature: Option<f64>,
295    #[serde(skip_serializing_if = "Option::is_none")]
296    pub top_p: Option<f64>,
297    #[serde(skip_serializing_if = "Option::is_none")]
298    pub top_k: Option<usize>,
299}
300
301#[derive(Debug, Serialize, Deserialize)]
302#[serde(rename_all = "camelCase")]
303pub struct SafetySetting {
304    pub category: HarmCategory,
305    pub threshold: HarmBlockThreshold,
306}
307
308#[derive(Debug, Serialize, Deserialize)]
309pub enum HarmCategory {
310    #[serde(rename = "HARM_CATEGORY_UNSPECIFIED")]
311    Unspecified,
312    #[serde(rename = "HARM_CATEGORY_DEROGATORY")]
313    Derogatory,
314    #[serde(rename = "HARM_CATEGORY_TOXICITY")]
315    Toxicity,
316    #[serde(rename = "HARM_CATEGORY_VIOLENCE")]
317    Violence,
318    #[serde(rename = "HARM_CATEGORY_SEXUAL")]
319    Sexual,
320    #[serde(rename = "HARM_CATEGORY_MEDICAL")]
321    Medical,
322    #[serde(rename = "HARM_CATEGORY_DANGEROUS")]
323    Dangerous,
324    #[serde(rename = "HARM_CATEGORY_HARASSMENT")]
325    Harassment,
326    #[serde(rename = "HARM_CATEGORY_HATE_SPEECH")]
327    HateSpeech,
328    #[serde(rename = "HARM_CATEGORY_SEXUALLY_EXPLICIT")]
329    SexuallyExplicit,
330    #[serde(rename = "HARM_CATEGORY_DANGEROUS_CONTENT")]
331    DangerousContent,
332}
333
334#[derive(Debug, Serialize, Deserialize)]
335#[serde(rename_all = "SCREAMING_SNAKE_CASE")]
336pub enum HarmBlockThreshold {
337    #[serde(rename = "HARM_BLOCK_THRESHOLD_UNSPECIFIED")]
338    Unspecified,
339    BlockLowAndAbove,
340    BlockMediumAndAbove,
341    BlockOnlyHigh,
342    BlockNone,
343}
344
345#[derive(Debug, Serialize, Deserialize)]
346#[serde(rename_all = "SCREAMING_SNAKE_CASE")]
347pub enum HarmProbability {
348    #[serde(rename = "HARM_PROBABILITY_UNSPECIFIED")]
349    Unspecified,
350    Negligible,
351    Low,
352    Medium,
353    High,
354}
355
356#[derive(Debug, Serialize, Deserialize)]
357#[serde(rename_all = "camelCase")]
358pub struct SafetyRating {
359    pub category: HarmCategory,
360    pub probability: HarmProbability,
361}
362
363#[derive(Debug, Serialize, Deserialize)]
364#[serde(rename_all = "camelCase")]
365pub struct CountTokensRequest {
366    pub generate_content_request: GenerateContentRequest,
367}
368
369#[derive(Debug, Serialize, Deserialize)]
370#[serde(rename_all = "camelCase")]
371pub struct CountTokensResponse {
372    pub total_tokens: usize,
373}
374
375#[derive(Debug, Serialize, Deserialize)]
376pub struct FunctionCall {
377    pub name: String,
378    pub args: serde_json::Value,
379}
380
381#[derive(Debug, Serialize, Deserialize)]
382pub struct FunctionResponse {
383    pub name: String,
384    pub response: serde_json::Value,
385}
386
387#[derive(Debug, Serialize, Deserialize)]
388#[serde(rename_all = "camelCase")]
389pub struct Tool {
390    pub function_declarations: Vec<FunctionDeclaration>,
391}
392
393#[derive(Debug, Serialize, Deserialize)]
394#[serde(rename_all = "camelCase")]
395pub struct ToolConfig {
396    pub function_calling_config: FunctionCallingConfig,
397}
398
399#[derive(Debug, Serialize, Deserialize)]
400#[serde(rename_all = "camelCase")]
401pub struct FunctionCallingConfig {
402    pub mode: FunctionCallingMode,
403    #[serde(skip_serializing_if = "Option::is_none")]
404    pub allowed_function_names: Option<Vec<String>>,
405}
406
407#[derive(Debug, Serialize, Deserialize)]
408#[serde(rename_all = "lowercase")]
409pub enum FunctionCallingMode {
410    Auto,
411    Any,
412    None,
413}
414
415#[derive(Debug, Serialize, Deserialize)]
416pub struct FunctionDeclaration {
417    pub name: String,
418    pub description: String,
419    pub parameters: serde_json::Value,
420}
421
422#[derive(Debug, Default)]
423pub struct ModelName {
424    pub model_id: String,
425}
426
427impl ModelName {
428    pub fn is_empty(&self) -> bool {
429        self.model_id.is_empty()
430    }
431}
432
433const MODEL_NAME_PREFIX: &str = "models/";
434
435impl Serialize for ModelName {
436    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
437    where
438        S: Serializer,
439    {
440        serializer.serialize_str(&format!("{MODEL_NAME_PREFIX}{}", &self.model_id))
441    }
442}
443
444impl<'de> Deserialize<'de> for ModelName {
445    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
446    where
447        D: Deserializer<'de>,
448    {
449        let string = String::deserialize(deserializer)?;
450        if let Some(id) = string.strip_prefix(MODEL_NAME_PREFIX) {
451            Ok(Self {
452                model_id: id.to_string(),
453            })
454        } else {
455            return Err(serde::de::Error::custom(format!(
456                "Expected model name to begin with {}, got: {}",
457                MODEL_NAME_PREFIX, string
458            )));
459        }
460    }
461}
462
463#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
464#[derive(Clone, Default, Debug, Deserialize, Serialize, PartialEq, Eq, strum::EnumIter)]
465pub enum Model {
466    #[serde(rename = "gemini-1.5-pro")]
467    Gemini15Pro,
468    #[serde(rename = "gemini-1.5-flash")]
469    Gemini15Flash,
470    #[serde(rename = "gemini-2.0-pro-exp")]
471    Gemini20Pro,
472    #[serde(rename = "gemini-2.0-flash")]
473    #[default]
474    Gemini20Flash,
475    #[serde(rename = "gemini-2.0-flash-thinking-exp")]
476    Gemini20FlashThinking,
477    #[serde(rename = "gemini-2.0-flash-lite-preview")]
478    Gemini20FlashLite,
479    #[serde(rename = "gemini-2.5-pro-exp-03-25")]
480    Gemini25ProExp0325,
481    #[serde(rename = "gemini-2.5-pro-preview-03-25")]
482    Gemini25ProPreview0325,
483    #[serde(rename = "gemini-2.5-flash-preview-04-17")]
484    Gemini25FlashPreview0417,
485    #[serde(rename = "custom")]
486    Custom {
487        name: String,
488        /// The name displayed in the UI, such as in the assistant panel model dropdown menu.
489        display_name: Option<String>,
490        max_tokens: usize,
491    },
492}
493
494impl Model {
495    pub fn default_fast() -> Model {
496        Model::Gemini20Flash
497    }
498
499    pub fn id(&self) -> &str {
500        match self {
501            Model::Gemini15Pro => "gemini-1.5-pro",
502            Model::Gemini15Flash => "gemini-1.5-flash",
503            Model::Gemini20Pro => "gemini-2.0-pro-exp",
504            Model::Gemini20Flash => "gemini-2.0-flash",
505            Model::Gemini20FlashThinking => "gemini-2.0-flash-thinking-exp",
506            Model::Gemini20FlashLite => "gemini-2.0-flash-lite-preview",
507            Model::Gemini25ProExp0325 => "gemini-2.5-pro-exp-03-25",
508            Model::Gemini25ProPreview0325 => "gemini-2.5-pro-preview-03-25",
509            Model::Gemini25FlashPreview0417 => "gemini-2.5-flash-preview-04-17",
510            Model::Custom { name, .. } => name,
511        }
512    }
513
514    pub fn display_name(&self) -> &str {
515        match self {
516            Model::Gemini15Pro => "Gemini 1.5 Pro",
517            Model::Gemini15Flash => "Gemini 1.5 Flash",
518            Model::Gemini20Pro => "Gemini 2.0 Pro",
519            Model::Gemini20Flash => "Gemini 2.0 Flash",
520            Model::Gemini20FlashThinking => "Gemini 2.0 Flash Thinking",
521            Model::Gemini20FlashLite => "Gemini 2.0 Flash Lite",
522            Model::Gemini25ProExp0325 => "Gemini 2.5 Pro Exp",
523            Model::Gemini25ProPreview0325 => "Gemini 2.5 Pro Preview",
524            Model::Gemini25FlashPreview0417 => "Gemini 2.5 Flash Preview",
525            Self::Custom {
526                name, display_name, ..
527            } => display_name.as_ref().unwrap_or(name),
528        }
529    }
530
531    pub fn max_token_count(&self) -> usize {
532        const ONE_MILLION: usize = 1_048_576;
533        const TWO_MILLION: usize = 2_097_152;
534        match self {
535            Model::Gemini15Pro => TWO_MILLION,
536            Model::Gemini15Flash => ONE_MILLION,
537            Model::Gemini20Pro => TWO_MILLION,
538            Model::Gemini20Flash => ONE_MILLION,
539            Model::Gemini20FlashThinking => ONE_MILLION,
540            Model::Gemini20FlashLite => ONE_MILLION,
541            Model::Gemini25ProExp0325 => ONE_MILLION,
542            Model::Gemini25ProPreview0325 => ONE_MILLION,
543            Model::Gemini25FlashPreview0417 => ONE_MILLION,
544            Model::Custom { max_tokens, .. } => *max_tokens,
545        }
546    }
547}
548
549impl std::fmt::Display for Model {
550    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
551        write!(f, "{}", self.id())
552    }
553}