Recent breaking changes & Migration guidance

[tholor]

In preparation for Haystack 1.0, we conduct some major refactorings in the next weeks incl. several breaking changes.

We will keep a list of breaking changes here to help you migrate your own Haystack scripts and applications.

Refactoring of primitives (#1398)

We improved the basic datatypes. This might particularly break your code to

• write Documents to the doc store
• process Answers from a pipeline / reader

Document

• Renamed Document.text -> Document.content
• Removed Document.question (was only used a while ago in FAQ search cases)
• Rename text_field -> content_field in ElasticsearchDocumentStore & Weaviate init
• Remove faq_question_field in ElasticsearchDocumentStore & Weaviate init

Label

• Rename Label.question -> Label.query
• Make Label.answer an Answer obj rather than plain str
• Remove Label.document_id (can now be accessed via Label.document.id)
• Rename Label.model_id -> Label.pipeline_id
• Remove Label.offset_start_in_doc (can now be accessed via label.answer.offsets_in_document[0].start`

Answer

The reader returns now an Answer object rather than a dict.
It follows this new structure:

Particularly the handling of offsets has changed to be more explicit and allow for other multiple spans (e.g. TableQA):

# Old -> New 

answer["offset_start_in_doc"] -> answer.offsets_in_document[0].start
answer["offset_end_in_doc"] -> answer.offsets_in_document[0].end

answer["offset_start"] -> answer.offset_in_context[0].start
answer["offset_end"] -> answer.offset_in_context[0].end

[pk1130]

Hey @tholor! Apologies for commenting on a pinned message. I have recently installed haystack on my local machine using the git+https method. Since I haven't used the repo too much yet, would it work to do a pip reinstall to get the newest version of Haystack working on my machine? I'm specifically using Haystack for building a retriever using DPR.

Thanks a ton!

[ZanSara]

Hey @pk1130, if you installed Haystack with:

pip install git+https://github.com/deepset-ai/haystack.git

then you should reinstall it with pip.

Instead, if you installed it with:

git clone https://github.com/deepset-ai/haystack.git
cd haystack
pip install --editable .

then you should go in the root haystack folder and pull the latest master with:

git pull
pip install dataclasses-json

There is no need to pip reinstall Haystack after that (given that you used the option --editable as above).

Hope it helps!

---

PS: next time please open a separate issue 😉

[ZanSara]

As we have now a migrating guide and this is becoming obsolete, I will close this issue. Please open a new one if you face migration issues 🙂