Processor config chat template (#1954)

This PR loads the `processor_config` similar to the `tokenizer_config`
and uses the processor_config's chat_template if the tokenizer_config
does not include one. These changes enable chat with idefics2

router/src/infer.rs

@@ -2,7 +2,8 @@
 use crate::validation::{Validation, ValidationError};
 use crate::{
     ChatTemplateInputs, ChatTemplateVersions, Entry, GenerateRequest, GenerateStreamResponse,
-    HubTokenizerConfig, Message, MessageChunk, PrefillToken, Queue, Text, TextMessage, Token,
+    HubProcessorConfig, HubTokenizerConfig, Message, MessageChunk, PrefillToken, Queue, Text,
+    TextMessage, Token,
 };
 use crate::{FunctionRef, FunctionsMap, GrammarType, Properties, Tool, ToolType, Tools};
 use futures::future::try_join_all;
@@ -67,6 +68,7 @@ impl Infer {
         speculate: u32,
         generation_health: Arc<AtomicBool>,
         tokenizer_config: HubTokenizerConfig,
+        processor_config: HubProcessorConfig,
     ) -> Self {
         // Infer shared state
         let queue = Queue::new(requires_padding, 16, window_size, speculate);
@@ -89,6 +91,7 @@ impl Infer {
 
         let chat_template = tokenizer_config
             .chat_template
+            .or(processor_config.chat_template)
             .and_then(|t| match t {
                 ChatTemplateVersions::Single(template) => Some(template),
                 ChatTemplateVersions::Multiple(templates) => templates
@@ -98,7 +101,10 @@ impl Infer {
             })
             .map(|t| {
                 // .strip() is not supported in minijinja
-                let t = t.replace(".strip()", " | trim");
+                // .capitalize() is not supported in minijinja but we can use | capitalize
+                let t = t
+                    .replace(".strip()", " | trim")
+                    .replace(".capitalize()", " | capitalize");
                 ChatTemplate::new(t, tokenizer_config.bos_token, tokenizer_config.eos_token)
             });
 

router/src/lib.rs

@@ -80,6 +80,20 @@ impl HubTokenizerConfig {
     }
 }
 
+#[derive(Debug, Clone, Deserialize, Default)]
+pub struct HubProcessorConfig {
+    pub chat_template: Option<ChatTemplateVersions>,
+    pub image_seq_len: usize,
+    pub processor_class: Option<String>,
+}
+
+impl HubProcessorConfig {
+    pub fn from_file<P: AsRef<std::path::Path>>(filename: P) -> Option<Self> {
+        let content = std::fs::read_to_string(filename).ok()?;
+        serde_json::from_str(&content).ok()
+    }
+}
+
 #[derive(Clone, Debug, Deserialize, ToSchema, Serialize)]
 #[serde(tag = "type", content = "value")]
 pub(crate) enum GrammarType {

router/src/main.rs

@@ -14,7 +14,7 @@ use std::net::{IpAddr, Ipv4Addr, SocketAddr};
 use std::path::{Path, PathBuf};
 use text_generation_client::{ClientError, ShardedClient};
 use text_generation_router::config::Config;
-use text_generation_router::{server, HubModelInfo, HubTokenizerConfig};
+use text_generation_router::{server, HubModelInfo, HubProcessorConfig, HubTokenizerConfig};
 use thiserror::Error;
 use tokenizers::Tokenizer;
 use tower_http::cors::AllowOrigin;
@@ -206,11 +206,18 @@ async fn main() -> Result<(), RouterError> {
     };
 
     // Load tokenizer and model info
-    let (tokenizer_filename, config_filename, tokenizer_config_filename, model_info) = match api {
+    let (
+        tokenizer_filename,
+        config_filename,
+        tokenizer_config_filename,
+        processor_config_filename,
+        model_info,
+    ) = match api {
         Type::None => (
             Some(local_path.join("tokenizer.json")),
             Some(local_path.join("config.json")),
             Some(local_path.join("tokenizer_config.json")),
+            Some(local_path.join("processor_config.json")),
             None,
         ),
         Type::Api(api) => {
@@ -226,6 +233,7 @@ async fn main() -> Result<(), RouterError> {
             };
             let config_filename = api_repo.get("config.json").await.ok();
             let tokenizer_config_filename = api_repo.get("tokenizer_config.json").await.ok();
+            let processor_config_filename = api_repo.get("processor_config.json").await.ok();
 
             let model_info = if let Some(model_info) = get_model_info(&api_repo).await {
                 Some(model_info)
@@ -237,6 +245,7 @@ async fn main() -> Result<(), RouterError> {
                 tokenizer_filename,
                 config_filename,
                 tokenizer_config_filename,
+                processor_config_filename,
                 model_info,
             )
         }
@@ -250,6 +259,7 @@ async fn main() -> Result<(), RouterError> {
                 repo.get("tokenizer.json"),
                 repo.get("config.json"),
                 repo.get("tokenizer_config.json"),
+                repo.get("processor_config.json"),
                 None,
             )
         }
@@ -286,6 +296,10 @@ async fn main() -> Result<(), RouterError> {
         HubTokenizerConfig::default()
     });
 
+    let processor_config = processor_config_filename
+        .and_then(HubProcessorConfig::from_file)
+        .unwrap_or_default();
+
     tracing::info!("Using config {config:?}");
     if tokenizer.is_none() {
         tracing::warn!("Could not find a fast tokenizer implementation for {tokenizer_name}");
@@ -397,6 +411,7 @@ async fn main() -> Result<(), RouterError> {
         ngrok_authtoken,
         ngrok_edge,
         tokenizer_config,
+        processor_config,
         messages_api_enabled,
         disable_grammar_support,
         max_client_batch_size,

router/src/server.rs

@@ -5,9 +5,9 @@ use crate::infer::{InferError, InferResponse, InferStreamResponse, ToolGrammar};
 use crate::validation::ValidationError;
 use crate::{
     BestOfSequence, Details, ErrorResponse, FinishReason, GenerateParameters, GenerateRequest,
-    GenerateResponse, GrammarType, HubModelInfo, HubTokenizerConfig, Infer, Info, Message,
-    PrefillToken, SimpleToken, StreamDetails, StreamResponse, Token, TokenizeResponse, Usage,
-    Validation,
+    GenerateResponse, GrammarType, HubModelInfo, HubProcessorConfig, HubTokenizerConfig, Infer,
+    Info, Message, PrefillToken, SimpleToken, StreamDetails, StreamResponse, Token,
+    TokenizeResponse, Usage, Validation,
 };
 use crate::{
     ChatCompletion, ChatCompletionChoice, ChatCompletionChunk, ChatCompletionComplete,
@@ -1395,6 +1395,7 @@ pub async fn run(
     ngrok_authtoken: Option<String>,
     ngrok_edge: Option<String>,
     tokenizer_config: HubTokenizerConfig,
+    processor_config: HubProcessorConfig,
     messages_api_enabled: bool,
     grammar_support: bool,
     max_client_batch_size: usize,
@@ -1495,6 +1496,7 @@ pub async fn run(
         shard_info.speculate,
         generation_health,
         tokenizer_config,
+        processor_config,
     );
 
     // Duration buckets