Add builders for GenerateContent and CountToken

examples/count-tokens.rs

@@ -15,12 +15,7 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
     );
 
     let prompt = "What is the airspeed of an unladen swallow?";
-    let request = CountTokensRequest {
+    let request = CountTokensRequestBuilder::from_prompt(prompt).build();
-        contents: Content {
-            role: Some("user".to_string()),
-            parts: Some(vec![Part::Text(prompt.to_string())]),
-        },
-    };
     let result = gemini.count_tokens(&request, "gemini-pro").await?;
     println!("Response: {:?}", result);
 

examples/google-search-retrieval.rs

@@ -19,7 +19,7 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
 
     let request = GenerateContentRequest {
         contents: vec![Content {
-            role: Some("user".to_string()),
+            role: Some(Role::User),
             parts: Some(vec![Part::Text(prompt.to_string())]),
         }],
         tools: Some(vec![Tools {

examples/json-schema.rs

@@ -18,7 +18,7 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
     let prompt = "Generate 10 ideas of blog posts with a title and decription for each idea.";
     let request = GenerateContentRequest {
         contents: vec![Content {
-            role: Some("user".to_string()),
+            role: Some(Role::User),
             parts: Some(vec![Part::Text(prompt.to_string())]),
         }],
         generation_config: Some(GenerationConfig {

examples/safety-setting.rs

@@ -20,7 +20,7 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
 
     let request = GenerateContentRequest {
         contents: vec![Content {
-            role: Some("user".to_string()),
+            role: Some(Role::User),
             parts: Some(vec![Part::Text(prompt.to_string())]),
         }],
         safety_settings: Some(vec![SafetySetting {

examples/system_instruction.rs

@@ -20,7 +20,7 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
 
     let request = GenerateContentRequest {
         contents: vec![Content {
-            role: Some("user".to_string()),
+            role: Some(Role::User),
             parts: Some(vec![Part::Text(prompt.to_string())]),
         }],
         system_instruction: Some(Content {

examples/text-from-text.rs

@@ -15,8 +15,9 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
     );
 
     let prompt = "What is the airspeed of an unladen swallow?";
-    let result = gemini.prompt_text(prompt, None).await?;
+    let request = GenerateContentRequest::builder().with_prompt(prompt).build();
-    println!("Response: {}", result);
+    let response = gemini.generate_content(&request, "gemini-pro").await?;
+    println!("Response: {:?}", response.candidates[0].get_text().unwrap());
 
     Ok(())
 }

src/client.rs

@@ -5,14 +5,14 @@ use futures_util::stream::StreamExt;
 use reqwest_eventsource::{Event, EventSource};
 use tracing::error;
 
-use crate::dialogue::{Message, Role};
+use crate::dialogue::Message;
 use crate::error::{Error, Result};
 use crate::prelude::{
     Candidate, Content, CountTokensRequest, CountTokensResponse, GenerateContentRequest,
     GenerateContentResponse, GenerateContentResponseResult, GenerationConfig, TextEmbeddingRequest,
     TextEmbeddingResponse,
 };
-use crate::types::{PredictImageRequest, PredictImageResponse};
+use crate::types::{PredictImageRequest, PredictImageResponse, Role};
 use crate::{prelude::Part, token_provider::TokenProvider};
 
 pub static AUTH_SCOPE: &[&str] = &["https://www.googleapis.com/auth/cloud-platform"];
@@ -154,7 +154,7 @@ impl<T: TokenProvider + Clone> GeminiClient<T> {
             contents: messages
                 .iter()
                 .map(|m| Content {
-                    role: Some(m.role.to_string()),
+                    role: Some(m.role),
                     parts: Some(vec![Part::Text(m.text.clone())]),
                 })
                 .collect(),
@@ -177,6 +177,7 @@ impl<T: TokenProvider + Clone> GeminiClient<T> {
 
     /// Sends a text prompt to the Vertex API using the Gemini Pro model and extracts the text
     /// from the response.
+    #[deprecated(note = "Use `generate_content` instead")]
     pub async fn prompt_text(
         &self,
         prompt: &str,
@@ -184,7 +185,7 @@ impl<T: TokenProvider + Clone> GeminiClient<T> {
     ) -> Result<String> {
         let request = GenerateContentRequest {
             contents: vec![Content {
-                role: Some("user".to_string()),
+                role: Some(Role::User),
                 parts: Some(vec![Part::Text(prompt.to_string())]),
             }],
             generation_config: generation_config.cloned(),

src/dialogue.rs

@@ -1,35 +1,6 @@
-use std::str::FromStr;
-
 use serde::{Deserialize, Serialize};
 
-use crate::{client::GeminiClient, error::Result, prelude::TokenProvider};
+use crate::{client::GeminiClient, error::Result, prelude::TokenProvider, types::Role};
-
-#[derive(Clone, Debug, Serialize, Deserialize)]
-pub enum Role {
-    User,
-    Model,
-}
-
-impl ToString for Role {
-    fn to_string(&self) -> String {
-        match self {
-            Role::User => "user".to_string(),
-            Role::Model => "model".to_string(),
-        }
-    }
-}
-
-impl FromStr for Role {
-    type Err = ();
-
-    fn from_str(s: &str) -> std::result::Result<Self, Self::Err> {
-        match s {
-            "user" => Ok(Role::User),
-            "model" => Ok(Role::Model),
-            _ => Err(()),
-        }
-    }
-}
 
 #[derive(Clone, Debug, Serialize, Deserialize)]
 pub struct Message {

src/types/common.rs

@@ -1,10 +1,10 @@
-use std::collections::HashMap;
+use std::{collections::HashMap, str::FromStr};
 
 use serde::{Deserialize, Serialize};
 
-#[derive(Clone, Debug, Serialize, Deserialize)]
+#[derive(Clone, Default, Debug, Serialize, Deserialize)]
 pub struct Content {
-    pub role: Option<String>,
+    pub role: Option<Role>,
     pub parts: Option<Vec<Part>>,
 }
 
@@ -22,6 +22,34 @@ impl Content {
     }
 }
 
+#[derive(Clone, Copy, Debug, Serialize, Deserialize)]
+#[serde(rename_all = "lowercase")]
+pub enum Role {
+    User,
+    Model,
+}
+
+impl ToString for Role {
+    fn to_string(&self) -> String {
+        match self {
+            Role::User => "user".to_string(),
+            Role::Model => "model".to_string(),
+        }
+    }
+}
+
+impl FromStr for Role {
+    type Err = ();
+
+    fn from_str(s: &str) -> std::result::Result<Self, Self::Err> {
+        match s {
+            "user" => Ok(Role::User),
+            "model" => Ok(Role::Model),
+            _ => Err(()),
+        }
+    }
+}
+
 #[derive(Clone, Debug, Serialize, Deserialize)]
 #[serde(rename_all = "camelCase")]
 pub enum Part {

src/types/count_tokens.rs

@@ -7,6 +7,39 @@ pub struct CountTokensRequest {
     pub contents: Content,
 }
 
+impl CountTokensRequest {
+    pub fn builder() -> CountTokensRequestBuilder {
+        CountTokensRequestBuilder::new()
+    }
+}
+
+pub struct CountTokensRequestBuilder {
+    contents: Content,
+}
+
+impl CountTokensRequestBuilder {
+    pub fn new() -> Self {
+        CountTokensRequestBuilder {
+            contents: Content::default(),
+        }
+    }
+
+    pub fn from_prompt(prompt: &str) -> Self {
+        CountTokensRequestBuilder {
+            contents: Content {
+                parts: Some(vec![super::Part::Text(prompt.to_string())]),
+                ..Default::default()
+            },
+        }
+    }
+
+    pub fn build(self) -> CountTokensRequest {
+        CountTokensRequest {
+            contents: self.contents,
+        }
+    }
+}
+
 #[derive(Debug, Serialize, Deserialize)]
 #[serde(untagged)]
 pub enum CountTokensResponse {

src/types/generate_content.rs

@@ -3,7 +3,7 @@ use std::collections::HashMap;
 use serde::{Deserialize, Serialize};
 use serde_json::Value;
 
-use super::{Content, Part, VertexApiError};
+use super::{Content, Part, Role, VertexApiError};
 use crate::error::Result;
 
 #[derive(Clone, Default, Serialize, Deserialize)]
@@ -24,7 +24,7 @@ impl GenerateContentRequest {
     pub fn from_prompt(prompt: &str, generation_config: Option<GenerationConfig>) -> Self {
         GenerateContentRequest {
             contents: vec![Content {
-                role: Some("user".to_string()),
+                role: Some(Role::User),
                 parts: Some(vec![Part::Text(prompt.to_string())]),
             }],
             generation_config,
@@ -33,6 +33,54 @@ impl GenerateContentRequest {
             safety_settings: None,
         }
     }
+
+    pub fn builder() -> GenerateContentRequestBuilder {
+        GenerateContentRequestBuilder::new()
+    }
+}
+
+pub struct GenerateContentRequestBuilder {
+    request: GenerateContentRequest,
+}
+
+impl GenerateContentRequestBuilder {
+    fn new() -> Self {
+        GenerateContentRequestBuilder {
+            request: GenerateContentRequest::default(),
+        }
+    }
+
+    pub fn with_prompt(mut self, prompt: &str) -> Self {
+        self.request.contents = vec![Content {
+            role: Some(Role::User),
+            parts: Some(vec![Part::Text(prompt.to_string())]),
+        }];
+        self
+    }
+
+    pub fn with_generation_config(mut self, generation_config: GenerationConfig) -> Self {
+        self.request.generation_config = Some(generation_config);
+        self
+    }
+
+    pub fn with_tools(mut self, tools: Vec<Tools>) -> Self {
+        self.request.tools = Some(tools);
+        self
+    }
+
+    pub fn with_safety_settings(mut self, safety_settings: Vec<SafetySetting>) -> Self {
+        self.request.safety_settings = Some(safety_settings);
+        self
+    }
+
+    pub fn with_system_instruction(mut self, system_instruction: Content) -> Self {
+        self.request.system_instruction = Some(system_instruction);
+        self
+    }
+
+    pub fn build(self) -> GenerateContentRequest {
+        self.request
+    }
 }
 
 #[derive(Clone, Default, Serialize, Deserialize)]