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 {
-        contents: Content {
-            role: Some("user".to_string()),
-            parts: Some(vec![Part::Text(prompt.to_string())]),
-        },
-    };
+    let request = CountTokensRequestBuilder::from_prompt(prompt).build();
     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?;
-    println!("Response: {}", result);
+    let request = GenerateContentRequest::builder().with_prompt(prompt).build();
+    let response = gemini.generate_content(&request, "gemini-pro").await?;
+    println!("Response: {:?}", response.candidates[0].get_text().unwrap());
 
     Ok(())
 }