All geek questions in one place

Recommended approach for loading CouchDB documentation in Python?

I am very new to the couch, but I am trying to use it in a new Python project, and I would like to use python to write project documents (views). I have already configured Couch to use the couchpy view server, and I can confirm this by introducing some simple map / reduce functions in Futon.

Are there any official recommendations on how to load / sync project documents when using the couchdb Python module?

I understand that I can publish design documents to “install” them on Couch, but my question is really related to best practices. I need some kind of strategy for deployment, both in development and production environments. My intuition is to create a directory and store all my project documents there, and then write some kind of synchronization script that will load each of them into the couch (maybe just blindly rewriting what is already there). Is that a good idea?

Documentation for Writing Views in Python "is 5 suggestions, and actually just explains how to install couchpy. On a website

+6
source share
1 answer

Here's an approach that seems reasonable. First, I subclass couchdb.design.ViewDefinition. (Comments and pydocs are removed for brevity.)

import couchdb.design import inflection DESIGN_NAME="version" class CurrentVersion(couchdb.design.ViewDefinition): def __init__(self): map_fun = self.__class__.map if hasattr(self.__class__, "reduce"): reduce_fun = self.__class__.reduce else: reduce_fun = None super_args = (DESIGN_NAME, inflection.underscore(self.__class__.__name__), map_fun, reduce_fun, 'python') super(CurrentVersion, self).__init__(*super_args) @staticmethod def map(doc): if 'version_key' in doc and 'created_ts' in doc: yield (doc['version_key'], [doc['_id'], doc['created_ts']]) @staticmethod def reduce(keys, values, rereduce): max_index = 0 for index, value in enumerate(values): if value[1] > values[max_index][1]: max_index = index return values[max_index]

Now if I want to sync:

 import couchdb.design from couchview.version import CurrentVersion db = get_couch_db() # omitted for brevity couchdb.design.ViewDefinition.sync_many(db, [CurrentVersion()], remove_missing=True)

The advantages of this approach are as follows:

  • Organization. All constructions / representations exist as modules / classes (respectively), located in one package.
  • Real code. My text editor will highlight the syntax. I can write unit tests against my map / reduce functions.

The ViewDefinition subprocess can also be used for queries.

 current_version_view = couchview.version.CurrentVersion() result = current_version_view(self.db, key=version_key)

It's not ready for production yet, but I think this is a big step compared to storing map / reduce functions inside string literals.

Edit: I eventually wrote a couple of blog posts on this topic, as I could not find any other sources of advice:

+3
source

Source: https://habr.com/ru/post/916384/

More articles:


All Articles