Struct ChatCompletionStreamResponseBuilder 

pub struct ChatCompletionStreamResponseBuilder { /* private fields */ }

Builder for ChatCompletionStreamResponse

Provides a fluent interface for constructing streaming chat completion chunks with sensible defaults.

Implementations

impl ChatCompletionStreamResponseBuilder

pub fn new(id: impl Into<String>, model: impl Into<String>) -> Self

Create a new builder with required fields

Arguments

• id: Completion ID (e.g., “chatcmpl_abc123”)
• model: Model name used for generation

pub fn copy_from_request(self, request: &ChatCompletionRequest) -> Self

Copy common fields from a ChatCompletionRequest

This populates the model field from the request.

pub fn object(self, object: impl Into<String>) -> Self

Set the object type (default: “chat.completion.chunk”)

pub fn created(self, timestamp: u64) -> Self

Set the creation timestamp (default: current time)

pub fn choices(self, choices: Vec<ChatStreamChoice>) -> Self

Set the choices

pub fn add_choice(self, choice: ChatStreamChoice) -> Self

Add a single choice (delta)

pub fn usage(self, usage: Usage) -> Self

Set usage information (typically sent in final chunk)

pub fn maybe_system_fingerprint( self, fingerprint: Option<impl Into<String>>, ) -> Self

Set system fingerprint if provided (handles Option)

pub fn maybe_usage(self, usage: Option<Usage>) -> Self

Set usage if provided (handles Option)

pub fn add_choice_content( self, index: u32, role: impl Into<String>, content: impl Into<String>, ) -> Self

Add a choice delta that sets role and content

pub fn add_choice_content_with_logprobs( self, index: u32, role: impl Into<String>, content: impl Into<String>, logprobs: Option<ChatLogProbs>, ) -> Self

Add a choice delta that sets role, content, and logprobs

pub fn add_choice_role(self, index: u32, role: impl Into<String>) -> Self

Add a choice delta that only sets role

pub fn add_choice_tool_args( self, index: u32, args_delta: impl Into<Cow<'static, str>>, ) -> Self

Add a choice delta that appends a tool-call arguments delta Uses Cow so you can pass &str or String without extra clones

pub fn add_choice_reasoning( self, index: u32, reasoning: impl Into<String>, ) -> Self

Add a choice delta that sets reasoning content (for models that stream reasoning)

pub fn add_choice_tool_name( self, index: u32, tool_call_id: impl Into<String>, function_name: impl Into<String>, ) -> Self

Add a choice delta for tool call with function name and ID

pub fn add_choice_tool_call_delta( self, index: u32, tool_call_delta: ToolCallDelta, ) -> Self

Add a choice delta with a pre-constructed ToolCallDelta Useful when you already have a ToolCallDelta object to emit

pub fn add_choice_finish_reason( self, index: u32, finish_reason: impl Into<String>, matched_stop: Option<Value>, ) -> Self

Add a choice with finish_reason (final chunk) This is used for the last chunk in a stream to signal completion

pub fn build(self) -> ChatCompletionStreamResponse

Build the ChatCompletionStreamResponse

Trait Implementations

impl Clone for ChatCompletionStreamResponseBuilder

fn clone(&self) -> ChatCompletionStreamResponseBuilder

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ChatCompletionStreamResponseBuilder

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.