Class: Langfuse::ChatPromptClient

Inherits:
Object
  • Object
show all
Defined in:
lib/langfuse/chat_prompt_client.rb

Overview

Chat prompt client for compiling chat prompts with variable substitution

Handles chat-based prompts from Langfuse, providing Mustache templating for variable substitution in role-based messages.

Examples:

Basic usage

prompt_data = api_client.get_prompt("support_chat")
chat_prompt = Langfuse::ChatPromptClient.new(prompt_data)
chat_prompt.compile(variables: { user_name: "Alice", issue: "login" })
# => [{ role: "system", content: "You are a support agent..." }, ...]

Accessing metadata

chat_prompt.name      # => "support_chat"
chat_prompt.version   # => 1
chat_prompt.labels    # => ["production"]

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(prompt_data) ⇒ ChatPromptClient

Initialize a new chat prompt client

Parameters:

  • prompt_data (Hash) —

    The prompt data from the API

Raises:

  • (ArgumentError) —

    if prompt data is invalid



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# File 'lib/langfuse/chat_prompt_client.rb', line 45

def initialize(prompt_data)
  validate_prompt_data!(prompt_data)

  @name = prompt_data["name"]
  @version = prompt_data["version"]
  @prompt = prompt_data["prompt"]
  @labels = prompt_data["labels"] || []
  @tags = prompt_data["tags"] || []
  @config = prompt_data["config"] || {}
end

Instance Attribute Details

#config ⇒ Hash (readonly)

Returns Prompt configuration.

Returns:

  • (Hash) —

    Prompt configuration



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# File 'lib/langfuse/chat_prompt_client.rb', line 36

def config
  @config
end

#labels ⇒ Array<String> (readonly)

Returns Labels assigned to this prompt.

Returns:

  • (Array<String>) —

    Labels assigned to this prompt



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# File 'lib/langfuse/chat_prompt_client.rb', line 30

def labels
  @labels
end

#name ⇒ String (readonly)

Returns Prompt name.

Returns:

  • (String) —

    Prompt name



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# File 'lib/langfuse/chat_prompt_client.rb', line 24

def name
  @name
end

#prompt ⇒ Array<Hash> (readonly)

Returns Array of message hashes with role and content.

Returns:

  • (Array<Hash>) —

    Array of message hashes with role and content



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# File 'lib/langfuse/chat_prompt_client.rb', line 39

def prompt
  @prompt
end

#tags ⇒ Array<String> (readonly)

Returns Tags assigned to this prompt.

Returns:

  • (Array<String>) —

    Tags assigned to this prompt



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# File 'lib/langfuse/chat_prompt_client.rb', line 33

def tags
  @tags
end

#version ⇒ Integer (readonly)

Returns Prompt version number.

Returns:

  • (Integer) —

    Prompt version number



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# File 'lib/langfuse/chat_prompt_client.rb', line 27

def version
  @version
end

Instance Method Details

#compile(**kwargs) ⇒ Array<Hash>

Compile the chat prompt with variable substitution

Returns an array of message hashes with roles and compiled content. Each message in the prompt will have its content compiled with the provided variables using Mustache templating.

Examples:

chat_prompt.compile(name: "Alice", topic: "Ruby")
# => [
#   { role: :system, content: "You are a helpful assistant." },
#   { role: :user, content: "Hello Alice, let's discuss Ruby!" }
# ]

Parameters:

  • kwargs (Hash) —

    Variables to substitute in message templates (as keyword arguments)

Returns:

  • (Array<Hash>) —

    Array of compiled messages with :role and :content keys



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# File 'lib/langfuse/chat_prompt_client.rb', line 71

def compile(**kwargs)
  prompt.map do |message|
    compile_message(message, kwargs)
  end
end