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Nikita Titov 9f2ab37162
community[patch]: don't try to parse json in case of errored response (#18317)
Related issue: #13896.

In case Ollama is behind a proxy, proxy error responses cannot be
viewed. You aren't even able to check response code.

For example, if your Ollama has basic access authentication and it's not
passed, `JSONDecodeError` will overwrite the truth response error.

<details>
<summary><b>Log now:</b></summary>

```
{
	"name": "JSONDecodeError",
	"message": "Expecting value: line 1 column 1 (char 0)",
	"stack": "---------------------------------------------------------------------------
JSONDecodeError                           Traceback (most recent call last)
File /opt/miniforge3/envs/.gpt/lib/python3.10/site-packages/requests/models.py:971, in Response.json(self, **kwargs)
    970 try:
--> 971     return complexjson.loads(self.text, **kwargs)
    972 except JSONDecodeError as e:
    973     # Catch JSON-related errors and raise as requests.JSONDecodeError
    974     # This aliases json.JSONDecodeError and simplejson.JSONDecodeError

File /opt/miniforge3/envs/.gpt/lib/python3.10/json/__init__.py:346, in loads(s, cls, object_hook, parse_float, parse_int, parse_constant, object_pairs_hook, **kw)
    343 if (cls is None and object_hook is None and
    344         parse_int is None and parse_float is None and
    345         parse_constant is None and object_pairs_hook is None and not kw):
--> 346     return _default_decoder.decode(s)
    347 if cls is None:

File /opt/miniforge3/envs/.gpt/lib/python3.10/json/decoder.py:337, in JSONDecoder.decode(self, s, _w)
    333 \"\"\"Return the Python representation of ``s`` (a ``str`` instance
    334 containing a JSON document).
    335 
    336 \"\"\"
--> 337 obj, end = self.raw_decode(s, idx=_w(s, 0).end())
    338 end = _w(s, end).end()

File /opt/miniforge3/envs/.gpt/lib/python3.10/json/decoder.py:355, in JSONDecoder.raw_decode(self, s, idx)
    354 except StopIteration as err:
--> 355     raise JSONDecodeError(\"Expecting value\", s, err.value) from None
    356 return obj, end

JSONDecodeError: Expecting value: line 1 column 1 (char 0)

During handling of the above exception, another exception occurred:

JSONDecodeError                           Traceback (most recent call last)
Cell In[3], line 1
----> 1 print(translate_func().invoke('text'))

File /opt/miniforge3/envs/.gpt/lib/python3.10/site-packages/langchain_core/runnables/base.py:2053, in RunnableSequence.invoke(self, input, config)
   2051 try:
   2052     for i, step in enumerate(self.steps):
-> 2053         input = step.invoke(
   2054             input,
   2055             # mark each step as a child run
   2056             patch_config(
   2057                 config, callbacks=run_manager.get_child(f\"seq:step:{i+1}\")
   2058             ),
   2059         )
   2060 # finish the root run
   2061 except BaseException as e:

File /opt/miniforge3/envs/.gpt/lib/python3.10/site-packages/langchain_core/language_models/chat_models.py:165, in BaseChatModel.invoke(self, input, config, stop, **kwargs)
    154 def invoke(
    155     self,
    156     input: LanguageModelInput,
   (...)
    160     **kwargs: Any,
    161 ) -> BaseMessage:
    162     config = ensure_config(config)
    163     return cast(
    164         ChatGeneration,
--> 165         self.generate_prompt(
    166             [self._convert_input(input)],
    167             stop=stop,
    168             callbacks=config.get(\"callbacks\"),
    169             tags=config.get(\"tags\"),
    170             metadata=config.get(\"metadata\"),
    171             run_name=config.get(\"run_name\"),
    172             **kwargs,
    173         ).generations[0][0],
    174     ).message

File /opt/miniforge3/envs/.gpt/lib/python3.10/site-packages/langchain_core/language_models/chat_models.py:543, in BaseChatModel.generate_prompt(self, prompts, stop, callbacks, **kwargs)
    535 def generate_prompt(
    536     self,
    537     prompts: List[PromptValue],
   (...)
    540     **kwargs: Any,
    541 ) -> LLMResult:
    542     prompt_messages = [p.to_messages() for p in prompts]
--> 543     return self.generate(prompt_messages, stop=stop, callbacks=callbacks, **kwargs)

File /opt/miniforge3/envs/.gpt/lib/python3.10/site-packages/langchain_core/language_models/chat_models.py:407, in BaseChatModel.generate(self, messages, stop, callbacks, tags, metadata, run_name, **kwargs)
    405         if run_managers:
    406             run_managers[i].on_llm_error(e, response=LLMResult(generations=[]))
--> 407         raise e
    408 flattened_outputs = [
    409     LLMResult(generations=[res.generations], llm_output=res.llm_output)
    410     for res in results
    411 ]
    412 llm_output = self._combine_llm_outputs([res.llm_output for res in results])

File /opt/miniforge3/envs/.gpt/lib/python3.10/site-packages/langchain_core/language_models/chat_models.py:397, in BaseChatModel.generate(self, messages, stop, callbacks, tags, metadata, run_name, **kwargs)
    394 for i, m in enumerate(messages):
    395     try:
    396         results.append(
--> 397             self._generate_with_cache(
    398                 m,
    399                 stop=stop,
    400                 run_manager=run_managers[i] if run_managers else None,
    401                 **kwargs,
    402             )
    403         )
    404     except BaseException as e:
    405         if run_managers:

File /opt/miniforge3/envs/.gpt/lib/python3.10/site-packages/langchain_core/language_models/chat_models.py:576, in BaseChatModel._generate_with_cache(self, messages, stop, run_manager, **kwargs)
    572     raise ValueError(
    573         \"Asked to cache, but no cache found at `langchain.cache`.\"
    574     )
    575 if new_arg_supported:
--> 576     return self._generate(
    577         messages, stop=stop, run_manager=run_manager, **kwargs
    578     )
    579 else:
    580     return self._generate(messages, stop=stop, **kwargs)

File /opt/miniforge3/envs/.gpt/lib/python3.10/site-packages/langchain_community/chat_models/ollama.py:250, in ChatOllama._generate(self, messages, stop, run_manager, **kwargs)
    226 def _generate(
    227     self,
    228     messages: List[BaseMessage],
   (...)
    231     **kwargs: Any,
    232 ) -> ChatResult:
    233     \"\"\"Call out to Ollama's generate endpoint.
    234 
    235     Args:
   (...)
    247             ])
    248     \"\"\"
--> 250     final_chunk = self._chat_stream_with_aggregation(
    251         messages,
    252         stop=stop,
    253         run_manager=run_manager,
    254         verbose=self.verbose,
    255         **kwargs,
    256     )
    257     chat_generation = ChatGeneration(
    258         message=AIMessage(content=final_chunk.text),
    259         generation_info=final_chunk.generation_info,
    260     )
    261     return ChatResult(generations=[chat_generation])

File /opt/miniforge3/envs/.gpt/lib/python3.10/site-packages/langchain_community/chat_models/ollama.py:183, in ChatOllama._chat_stream_with_aggregation(self, messages, stop, run_manager, verbose, **kwargs)
    174 def _chat_stream_with_aggregation(
    175     self,
    176     messages: List[BaseMessage],
   (...)
    180     **kwargs: Any,
    181 ) -> ChatGenerationChunk:
    182     final_chunk: Optional[ChatGenerationChunk] = None
--> 183     for stream_resp in self._create_chat_stream(messages, stop, **kwargs):
    184         if stream_resp:
    185             chunk = _chat_stream_response_to_chat_generation_chunk(stream_resp)

File /opt/miniforge3/envs/.gpt/lib/python3.10/site-packages/langchain_community/chat_models/ollama.py:156, in ChatOllama._create_chat_stream(self, messages, stop, **kwargs)
    147 def _create_chat_stream(
    148     self,
    149     messages: List[BaseMessage],
    150     stop: Optional[List[str]] = None,
    151     **kwargs: Any,
    152 ) -> Iterator[str]:
    153     payload = {
    154         \"messages\": self._convert_messages_to_ollama_messages(messages),
    155     }
--> 156     yield from self._create_stream(
    157         payload=payload, stop=stop, api_url=f\"{self.base_url}/api/chat/\", **kwargs
    158     )

File /opt/miniforge3/envs/.gpt/lib/python3.10/site-packages/langchain_community/llms/ollama.py:234, in _OllamaCommon._create_stream(self, api_url, payload, stop, **kwargs)
    228         raise OllamaEndpointNotFoundError(
    229             \"Ollama call failed with status code 404. \"
    230             \"Maybe your model is not found \"
    231             f\"and you should pull the model with `ollama pull {self.model}`.\"
    232         )
    233     else:
--> 234         optional_detail = response.json().get(\"error\")
    235         raise ValueError(
    236             f\"Ollama call failed with status code {response.status_code}.\"
    237             f\" Details: {optional_detail}\"
    238         )
    239 return response.iter_lines(decode_unicode=True)

File /opt/miniforge3/envs/.gpt/lib/python3.10/site-packages/requests/models.py:975, in Response.json(self, **kwargs)
    971     return complexjson.loads(self.text, **kwargs)
    972 except JSONDecodeError as e:
    973     # Catch JSON-related errors and raise as requests.JSONDecodeError
    974     # This aliases json.JSONDecodeError and simplejson.JSONDecodeError
--> 975     raise RequestsJSONDecodeError(e.msg, e.doc, e.pos)

JSONDecodeError: Expecting value: line 1 column 1 (char 0)"
}
```

</details>


<details>

<summary><b>Log after a fix:</b></summary>

```
{
	"name": "ValueError",
	"message": "Ollama call failed with status code 401. Details: <html>\r
<head><title>401 Authorization Required</title></head>\r
<body>\r
<center><h1>401 Authorization Required</h1></center>\r
<hr><center>nginx/1.18.0 (Ubuntu)</center>\r
</body>\r
</html>\r
",
	"stack": "---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)
Cell In[2], line 1
----> 1 print(translate_func().invoke('text'))

File /opt/miniforge3/envs/.gpt/lib/python3.10/site-packages/langchain_core/runnables/base.py:2053, in RunnableSequence.invoke(self, input, config)
   2051 try:
   2052     for i, step in enumerate(self.steps):
-> 2053         input = step.invoke(
   2054             input,
   2055             # mark each step as a child run
   2056             patch_config(
   2057                 config, callbacks=run_manager.get_child(f\"seq:step:{i+1}\")
   2058             ),
   2059         )
   2060 # finish the root run
   2061 except BaseException as e:

File /opt/miniforge3/envs/.gpt/lib/python3.10/site-packages/langchain_core/language_models/chat_models.py:165, in BaseChatModel.invoke(self, input, config, stop, **kwargs)
    154 def invoke(
    155     self,
    156     input: LanguageModelInput,
   (...)
    160     **kwargs: Any,
    161 ) -> BaseMessage:
    162     config = ensure_config(config)
    163     return cast(
    164         ChatGeneration,
--> 165         self.generate_prompt(
    166             [self._convert_input(input)],
    167             stop=stop,
    168             callbacks=config.get(\"callbacks\"),
    169             tags=config.get(\"tags\"),
    170             metadata=config.get(\"metadata\"),
    171             run_name=config.get(\"run_name\"),
    172             **kwargs,
    173         ).generations[0][0],
    174     ).message

File /opt/miniforge3/envs/.gpt/lib/python3.10/site-packages/langchain_core/language_models/chat_models.py:543, in BaseChatModel.generate_prompt(self, prompts, stop, callbacks, **kwargs)
    535 def generate_prompt(
    536     self,
    537     prompts: List[PromptValue],
   (...)
    540     **kwargs: Any,
    541 ) -> LLMResult:
    542     prompt_messages = [p.to_messages() for p in prompts]
--> 543     return self.generate(prompt_messages, stop=stop, callbacks=callbacks, **kwargs)

File /opt/miniforge3/envs/.gpt/lib/python3.10/site-packages/langchain_core/language_models/chat_models.py:407, in BaseChatModel.generate(self, messages, stop, callbacks, tags, metadata, run_name, **kwargs)
    405         if run_managers:
    406             run_managers[i].on_llm_error(e, response=LLMResult(generations=[]))
--> 407         raise e
    408 flattened_outputs = [
    409     LLMResult(generations=[res.generations], llm_output=res.llm_output)
    410     for res in results
    411 ]
    412 llm_output = self._combine_llm_outputs([res.llm_output for res in results])

File /opt/miniforge3/envs/.gpt/lib/python3.10/site-packages/langchain_core/language_models/chat_models.py:397, in BaseChatModel.generate(self, messages, stop, callbacks, tags, metadata, run_name, **kwargs)
    394 for i, m in enumerate(messages):
    395     try:
    396         results.append(
--> 397             self._generate_with_cache(
    398                 m,
    399                 stop=stop,
    400                 run_manager=run_managers[i] if run_managers else None,
    401                 **kwargs,
    402             )
    403         )
    404     except BaseException as e:
    405         if run_managers:

File /opt/miniforge3/envs/.gpt/lib/python3.10/site-packages/langchain_core/language_models/chat_models.py:576, in BaseChatModel._generate_with_cache(self, messages, stop, run_manager, **kwargs)
    572     raise ValueError(
    573         \"Asked to cache, but no cache found at `langchain.cache`.\"
    574     )
    575 if new_arg_supported:
--> 576     return self._generate(
    577         messages, stop=stop, run_manager=run_manager, **kwargs
    578     )
    579 else:
    580     return self._generate(messages, stop=stop, **kwargs)

File /opt/miniforge3/envs/.gpt/lib/python3.10/site-packages/langchain_community/chat_models/ollama.py:250, in ChatOllama._generate(self, messages, stop, run_manager, **kwargs)
    226 def _generate(
    227     self,
    228     messages: List[BaseMessage],
   (...)
    231     **kwargs: Any,
    232 ) -> ChatResult:
    233     \"\"\"Call out to Ollama's generate endpoint.
    234 
    235     Args:
   (...)
    247             ])
    248     \"\"\"
--> 250     final_chunk = self._chat_stream_with_aggregation(
    251         messages,
    252         stop=stop,
    253         run_manager=run_manager,
    254         verbose=self.verbose,
    255         **kwargs,
    256     )
    257     chat_generation = ChatGeneration(
    258         message=AIMessage(content=final_chunk.text),
    259         generation_info=final_chunk.generation_info,
    260     )
    261     return ChatResult(generations=[chat_generation])

File /storage/gpt-project/Repos/repo_nikita/gpt_lib/langchain/ollama.py:328, in ChatOllamaCustom._chat_stream_with_aggregation(self, messages, stop, run_manager, verbose, **kwargs)
    319 def _chat_stream_with_aggregation(
    320     self,
    321     messages: List[BaseMessage],
   (...)
    325     **kwargs: Any,
    326 ) -> ChatGenerationChunk:
    327     final_chunk: Optional[ChatGenerationChunk] = None
--> 328     for stream_resp in self._create_chat_stream(messages, stop, **kwargs):
    329         if stream_resp:
    330             chunk = _chat_stream_response_to_chat_generation_chunk(stream_resp)

File /storage/gpt-project/Repos/repo_nikita/gpt_lib/langchain/ollama.py:301, in ChatOllamaCustom._create_chat_stream(self, messages, stop, **kwargs)
    292 def _create_chat_stream(
    293     self,
    294     messages: List[BaseMessage],
    295     stop: Optional[List[str]] = None,
    296     **kwargs: Any,
    297 ) -> Iterator[str]:
    298     payload = {
    299         \"messages\": self._convert_messages_to_ollama_messages(messages),
    300     }
--> 301     yield from self._create_stream(
    302         payload=payload, stop=stop, api_url=f\"{self.base_url}/api/chat\", **kwargs
    303     )

File /storage/gpt-project/Repos/repo_nikita/gpt_lib/langchain/ollama.py:134, in _OllamaCommonCustom._create_stream(self, api_url, payload, stop, **kwargs)
    132     else:
    133         optional_detail = response.text
--> 134         raise ValueError(
    135             f\"Ollama call failed with status code {response.status_code}.\"
    136             f\" Details: {optional_detail}\"
    137         )
    138 return response.iter_lines(decode_unicode=True)

ValueError: Ollama call failed with status code 401. Details: <html>\r
<head><title>401 Authorization Required</title></head>\r
<body>\r
<center><h1>401 Authorization Required</h1></center>\r
<hr><center>nginx/1.18.0 (Ubuntu)</center>\r
</body>\r
</html>\r
"
}
```

</details>

The same is true for timeout errors or when you simply mistyped in
`base_url` arg and get response from some other service, for instance.

Real Ollama errors are still clearly readable:

```
ValueError: Ollama call failed with status code 400. Details: {"error":"invalid options: unknown_option"}
```

---------

Co-authored-by: Bagatur <baskaryan@gmail.com>
2024-03-01 12:17:29 -08:00
.devcontainer Update README.md (#8570) 2023-11-12 22:07:49 -08:00
.github astradb: move to langchain-datastax repo (#18354) 2024-03-01 19:04:43 +00:00
cookbook docs: cookbook on gemma integrations (#18213) 2024-03-01 11:50:55 -08:00
docker community[minor]: Add SQLDatabaseLoader document loader (#18281) 2024-02-28 21:02:28 +00:00
docs docs: Fix typo in baidu_qianfan_endpoint.ipynb & baidu_qianfan_endpoint.ipynb (#18176) 2024-03-01 12:10:23 -08:00
libs community[patch]: don't try to parse json in case of errored response (#18317) 2024-03-01 12:17:29 -08:00
templates templates: Lanceb RAG template (#17809) 2024-03-01 18:52:50 +00:00
.gitattributes Update dev container (#6189) 2023-06-16 15:42:14 -07:00
.gitignore airbyte[patch]: init pkg (#18236) 2024-02-27 19:37:53 -08:00
.readthedocs.yaml infra: update rtd yaml (#17502) 2024-02-13 18:16:44 -08:00
CITATION.cff rename repo namespace to langchain-ai (#11259) 2023-10-01 15:30:58 -04:00
LICENSE Library Licenses (#13300) 2023-11-28 17:34:27 -08:00
Makefile infra: simplify and fix CI for docs-only changes (#18058) 2024-02-23 16:39:08 -08:00
MIGRATE.md Update main readme (#13298) 2023-11-13 17:37:54 -08:00
poetry.lock text-splitters[minor], langchain[minor], community[patch], templates, docs: langchain-text-splitters 0.0.1 (#18346) 2024-02-29 18:33:21 -08:00
poetry.toml Unbreak devcontainer (#8154) 2023-07-23 19:33:47 -07:00
pyproject.toml text-splitters[minor], langchain[minor], community[patch], templates, docs: langchain-text-splitters 0.0.1 (#18346) 2024-02-29 18:33:21 -08:00
README.md Update contact link (#17563) 2024-02-14 22:37:32 -08:00
SECURITY.md Update SECURITY.md email address. (#9558) 2023-08-21 14:52:21 -04:00

🦜🔗 LangChain

Build context-aware reasoning applications

Release Notes CI Downloads License: MIT Twitter Open in Dev Containers Open in GitHub Codespaces GitHub star chart Dependency Status Open Issues

Looking for the JS/TS library? Check out LangChain.js.

To help you ship LangChain apps to production faster, check out LangSmith. LangSmith is a unified developer platform for building, testing, and monitoring LLM applications. Fill out this form to speak with our sales team.

Quick Install

With pip:

pip install langchain

With conda:

conda install langchain -c conda-forge

🤔 What is LangChain?

LangChain is a framework for developing applications powered by language models. It enables applications that:

  • Are context-aware: connect a language model to sources of context (prompt instructions, few shot examples, content to ground its response in, etc.)
  • Reason: rely on a language model to reason (about how to answer based on provided context, what actions to take, etc.)

This framework consists of several parts.

  • LangChain Libraries: The Python and JavaScript libraries. Contains interfaces and integrations for a myriad of components, a basic run time for combining these components into chains and agents, and off-the-shelf implementations of chains and agents.
  • LangChain Templates: A collection of easily deployable reference architectures for a wide variety of tasks.
  • LangServe: A library for deploying LangChain chains as a REST API.
  • LangSmith: A developer platform that lets you debug, test, evaluate, and monitor chains built on any LLM framework and seamlessly integrates with LangChain.
  • LangGraph: LangGraph is a library for building stateful, multi-actor applications with LLMs, built on top of (and intended to be used with) LangChain. It extends the LangChain Expression Language with the ability to coordinate multiple chains (or actors) across multiple steps of computation in a cyclic manner.

The LangChain libraries themselves are made up of several different packages.

  • langchain-core: Base abstractions and LangChain Expression Language.
  • langchain-community: Third party integrations.
  • langchain: Chains, agents, and retrieval strategies that make up an application's cognitive architecture.

Diagram outlining the hierarchical organization of the LangChain framework, displaying the interconnected parts across multiple layers.

🧱 What can you build with LangChain?

Retrieval augmented generation

💬 Analyzing structured data

🤖 Chatbots

And much more! Head to the Use cases section of the docs for more.

🚀 How does LangChain help?

The main value props of the LangChain libraries are:

  1. Components: composable tools and integrations for working with language models. Components are modular and easy-to-use, whether you are using the rest of the LangChain framework or not
  2. Off-the-shelf chains: built-in assemblages of components for accomplishing higher-level tasks

Off-the-shelf chains make it easy to get started. Components make it easy to customize existing chains and build new ones.

Components fall into the following modules:

📃 Model I/O:

This includes prompt management, prompt optimization, a generic interface for all LLMs, and common utilities for working with LLMs.

📚 Retrieval:

Data Augmented Generation involves specific types of chains that first interact with an external data source to fetch data for use in the generation step. Examples include summarization of long pieces of text and question/answering over specific data sources.

🤖 Agents:

Agents involve an LLM making decisions about which Actions to take, taking that Action, seeing an Observation, and repeating that until done. LangChain provides a standard interface for agents, a selection of agents to choose from, and examples of end-to-end agents.

📖 Documentation

Please see here for full documentation, which includes:

💁 Contributing

As an open-source project in a rapidly developing field, we are extremely open to contributions, whether it be in the form of a new feature, improved infrastructure, or better documentation.

For detailed information on how to contribute, see here.

🌟 Contributors

langchain contributors