feat(rig-1192): support pdf, image (openrouter) (#1404)

* feat(rig-1192): support pdf, image (openrouter)

* chore: fix merge conflict

Author: joshua-mo-143

rig/rig-core/examples/openrouter_multimodal.rs

@@ -0,0 +1,134 @@
+//! Example demonstrating OpenRouter's multimodal support for images and PDFs.
+//!
+//! This example shows how to send images and PDF documents to models via OpenRouter's API.
+//!
+//! OpenRouter supports:
+//! - Images via URL or base64 data URI
+//! - PDF files via URL or base64 data URI
+//!
+//! To run this example, set your OpenRouter API key:
+//! ```bash
+//! export OPENROUTER_API_KEY=your_api_key
+//! cargo run --example openrouter_multimodal
+//! ```
+
+use rig::OneOrMany;
+use rig::completion::Prompt;
+use rig::message::{
+    Document, DocumentMediaType, DocumentSourceKind, Image, ImageMediaType, Message, UserContent,
+};
+use rig::prelude::*;
+use rig::providers::openrouter;
+
+/// Model that supports vision (images)
+const VISION_MODEL: &str = "google/gemini-2.5-flash";
+
+#[tokio::main]
+async fn main() -> Result<(), anyhow::Error> {
+    // Initialize tracing for debugging
+    tracing_subscriber::fmt()
+        .with_max_level(tracing::Level::INFO)
+        .with_target(false)
+        .init();
+
+    // Create OpenRouter client
+    let client = openrouter::Client::from_env();
+
+    // Example 1: Analyze an image from URL
+    println!("=== Example 1: Image Analysis (URL) ===\n");
+    analyze_image_url(&client).await?;
+
+    // Example 2: Send a PDF document from URL
+    println!("\n=== Example 2: PDF Analysis (URL) ===\n");
+    analyze_pdf_url(&client).await?;
+
+    // Example 3: Mixed content - text with image
+    println!("\n=== Example 3: Mixed Content ===\n");
+    mixed_content(&client).await?;
+
+    Ok(())
+}
+
+/// Example: Analyze an image from a URL
+async fn analyze_image_url(client: &openrouter::Client) -> Result<(), anyhow::Error> {
+    let agent = client
+        .agent(VISION_MODEL)
+        .preamble("You are a helpful assistant that describes images in detail.")
+        .build();
+
+    // Create an image from URL using Rig's standard message types
+    let image_message = Message::User {
+        content: OneOrMany::many(vec![
+            UserContent::text("What do you see in this image? Describe it in detail."),
+            UserContent::Image(Image {
+                data: DocumentSourceKind::Url(
+                    "https://upload.wikimedia.org/wikipedia/commons/thumb/d/dd/Gfp-wisconsin-madison-the-nature-boardwalk.jpg/800px-Gfp-wisconsin-madison-the-nature-boardwalk.jpg".to_string()
+                ),
+                media_type: Some(ImageMediaType::JPEG),
+                detail: None,
+                additional_params: None,
+            }),
+        ])?,
+    };
+
+    let response = agent.prompt(image_message).await?;
+    println!("Response:\n{response}");
+
+    Ok(())
+}
+
+/// Example: Analyze a PDF document from a URL
+async fn analyze_pdf_url(client: &openrouter::Client) -> Result<(), anyhow::Error> {
+    let agent = client
+        .agent(VISION_MODEL)
+        .preamble("You are a helpful assistant that summarizes documents.")
+        .build();
+
+    // Create a document from URL using Rig's standard message types
+    // OpenRouter will automatically convert this to its file format
+    let pdf_message = Message::User {
+        content: OneOrMany::many(vec![
+            UserContent::text("Please summarize the key points of this document."),
+            UserContent::Document(Document {
+                data: DocumentSourceKind::Url("https://bitcoin.org/bitcoin.pdf".to_string()),
+                media_type: Some(DocumentMediaType::PDF),
+                additional_params: None,
+            }),
+        ])?,
+    };
+
+    let response = agent.prompt(pdf_message).await?;
+    println!("Response:\n{response}");
+
+    Ok(())
+}
+
+/// Example: Mixed content with text and image
+async fn mixed_content(client: &openrouter::Client) -> Result<(), anyhow::Error> {
+    let agent = client
+        .agent(VISION_MODEL)
+        .preamble("You are a helpful assistant.")
+        .build();
+
+    // Multiple content items in a single message
+    let message = Message::User {
+        content: OneOrMany::many(vec![
+            UserContent::text("I have two questions:"),
+            UserContent::text("1. What colors do you see in this image?"),
+            UserContent::Image(Image {
+                data: DocumentSourceKind::Url(
+                    "https://upload.wikimedia.org/wikipedia/commons/thumb/4/47/PNG_transparency_demonstration_1.png/280px-PNG_transparency_demonstration_1.png".to_string()
+                ),
+                media_type: Some(ImageMediaType::PNG),
+                detail: None,
+                additional_params: None,
+            }),
+            UserContent::text("2. What is the main subject?"),
+        ])?,
+    };
+
+    let response = agent.prompt(message).await?;
+    println!("Response:\n{response}");
+
+    Ok(())
+}