Query Pipeline#

Concept#

LlamaIndex provides a declarative query API that allows you to chain together different modules in order to orchestrate simple-to-advanced workflows over your data.

This is centered around our QueryPipeline abstraction. Load in a variety of modules (from LLMs to prompts to retrievers to other pipelines), connect them all together into a sequential chain or DAG, and run it end2end.

NOTE: You can orchestrate all these workflows without the declarative pipeline abstraction (by using the modules imperatively and writing your own functions). So what are the advantages of QueryPipeline?

  • Express common workflows with fewer lines of code/boilerplate

  • Greater readability

  • Greater parity / better integration points with common low-code / no-code solutions (e.g. LangFlow)

  • [In the future] A declarative interface allows easy serializability of pipeline components, providing portability of pipelines/easier deployment to different systems.

Our query pipelines also propagate callbacks throughout all sub-modules, and these integrate with our observability partners.

To see an interactive example of QueryPipeline being put in use, check out the RAG CLI.

Usage Pattern#

Here are two simple ways to setup a query pipeline - through a simplified syntax of setting up a sequential chain to setting up a full compute DAG.

from llama_index.core.query_pipeline import QueryPipeline

# sequential chain
p = QueryPipeline(chain=[prompt_tmpl, llm], verbose=True)

# DAG
p = QueryPipeline(verbose=True)
p.add_modules({"prompt_tmpl": prompt_tmpl, "llm": llm})
p.add_link("prompt_tmpl", "llm")

# run pipeline
p.run(prompt_key1="<input1>", ...)

More information can be found in our usage pattern guides below.