I'm designing a website with a REST API using Django Rest Framework and Vue for the front end and I'm trying to work out what the proper way to do filtering is.
As far as I can see, I can either:-
a) Allow filtering via the API by using URL parameters like /?foo=bar
or
b) Do all the filtering on the Vue side by only displaying the items that are returned that have foo=bar
Are there any strong reasons for doing one over the other?
The real answer to this question is "it depends".
Here are a few questions to ask yourself to help determine what the best approach is:
How much data will be returned if I don't filter at the API level?
If you're returning just a few records, there won't be a noticeable performance hit when the query runs. If you're returning thousands, you'll likely want to consider server side querying/paging.
If you're building an application where the amount of data will grow over time, it's best to build the server side querying from the get-go.
What do I want the front-end experience to be like?
For API calls that return small amounts of data, the user experience will be much more responsive if you return all records up front and do client-side filtering. That way if users change filters or click through paged data, the UI can update almost instantaneously.
Will any other applications be consuming my API?
If you plan to build other apps that consume the API, you may want to build the filtering at the API level so you don't need to recreate front-end filtering logic in every consuming application.
Hopefully these questions can help guide you to the best answer for your use case.
Whenever I come across this issue I ask myself just one question: How many items are you working with? If you're only returning a few items from the API you can easily do the filtering on the front-end side and save yourself a bunch of requests whenever the results are filtered. Also, if the result set is quite small, it's a lot faster to do it this way rather than sending off a request every time the filters change.
However, if you're working with a very large number of items, it's probably best to just filter them out in the API, or even via your database query if that's what you're working with. This will save you from returning a large number of results to the front-end. Also, filtering large numbers of items on the front-end can significantly impact performance since it usually involves looping over a collection.
Related
I want to develop github alike issue tracker.
For that i have been working on this below api.
https://api.github.com/repos/facebook/react/issues?per_page=100
But this api results only 100 results per request as per docs.
Is there a way i can get all results of issues and not just 100,i can make multiple request but i don't think it is feasible way of doing it.
Issue object itself contain author,label,assignee so needed all results at once.
Is there any way to do it?
No, there is no way to get all of the results without pagination. GitHub, like almost all major web sites, has a time limit on the amount of time a request can take. If you have a repository with, say, 150 000 issues, then any reasonable operation on all of those issues will take longer than the timeout. Therefore, it doesn't make sense for GitHub to allow you to disable pagination in this way because the request would invariably fail anyway.
Even if you use the GraphQL API, you still get a limited number of results. If you want to fetch all of the issues, you'll need to make multiple requests.
I supposed to write an API to provide the data to the front end. I've the following screen with filters by Shift/Day/Week/Month/6Months.
Though it's completely my business logic, In general I want to know the best practice in providing data for such filters.
1) Should I provide an API for each filter on click on each tab? With this approach, I'll have to execute db query for each time based on the filter.
2) Or, Should I provide an API once with all aggregated data with filter keys? So that from front end, client doesn't nave to invoke further API's on each click.
In this case, I'll have to execute multiple db queries at one and provide the data to the front end.
What is the best practice to achieve this? I know these are all part of architectural design and I'm in a learing process. Need a valid suggestion or a useful resource.
I am working with React Native/Redux and an express/postgresql backend.
I have an api call to create a comment that returns the created comment as well as some of the information concerning the user.
Those are two different api calls.
Now I also need the updated comment count to send to the feed reducer so that the count is still correct when they close the comment tab.
I was wondering if it is still okay to have 3 queries in one API call and maybe more general/meta, if there might be a better solution to this if that isn't the case.
Kind regards
It's perfectly fine to do multiple queries in a single API call. You can do as many as are required to complete a single coherent interaction between the server and client.
I want to make a REST API that does spellchecking on text that is passed in, without storing any of the text on the server.
The call would probably look something like `example.com/api/v1/spelling/mistakes', with optional query param for locale and an list of the mistakes as return value.
What would be the best HTTP method to use, given that the text passed in would be too large for a GET. Neither POST, PUT nor PATCH seem to reasonably map to the intended purpose and there don't seem to be any other suitable matches in the less commonly used methods either.
What is the best HTTP method to use for a "translation"-like REST API service, taking and returning large amounts of data?
I would say this is a POST. But it could have been a GET if the data was previously posted. The reason it is not a GET is because you are passing all the data in this API call, as you mentioned. For example, if the data was 'posted' somewhere else previously, then the GET can be used where the address (URI) of the location, or ID, of that 'posted' data is passed to the API as a param in the GET. But because we are both 'posting' the data and retrieving information about that in the same call, I would say then that this is a POST. Grant it the data being posted has a short life span, it is still being posted. If the data being posted was instead a customer order, then it would still be a POST but the data would be persisted somewhere. The difference here is the the short period of time that the data will exist for. And in future iterations of your API, you might actually want to keep that data and refer back to it with some ID. So by using POST you allow for future enhancements also.
By the way, as a precaution, be careful with the memory footprint of these calls. I can see this as being very memory intensive if the data being passed grows large and the API becomes very popular. Not a show stopped but something to consider when designing it.
Hope that helps alleviate what I call REST anxiety when designing an API.
What would be best practice for the following situation. I have an ecommerce store that pulls down inventory levels from a distributor. Should the site, for everytime a user loads a product detail page use the third party API for the most up to date data? Or, should the site using third party APIs and then store that data for a certain amount of time in it's own system and update it periodically?
To me it seems obvious that it should be updated everytime the product detail page is loaded but what about high traffic ecommerce stores? Are completely different solutions used for that case?
In this case I would definitely cache the results from the distributor's site for some period of time, rather than hitting them every time you get a request. However, I would not simply use a blanket 5 minute or 30 minute timeout for all cache entries. Instead, I would use some heuristics. If possible, for instance if your application is written in a language like Python, you could attach a simple script to every product which implements the timeout.
This way, if it is an item that is requested infrequently, or one that has a large amount in stock, you could cache for a longer time.
if product.popularityrating > 8 or product.lastqtyinstock < 20:
cache.expire(productnum)
distributor.checkstock(productnum)
This gives you flexibility that you can call on if you need it. Initially, you can set all the rules to something like:
cache.expireover("3m",productnum)
distributor.checkstock(productnum)
In actual fact, the script would probably not include the checkstock function call because that would be in the main app, but it is included here for context. If python seems too heavyweiaght to include just for this small amount of flexibilty, then have a look at TCL which was specifically designed for this type of job. Both can be embedded easily in C, C++, C# and Java applications.
Actually, there is another solution. Your distributor keeps the product catalog on their servers and gives you access to it via Open Catalog Interface. When a user wants to make an order he gets redirected in-place to the distributor's catalog, chooses items then transfers selection back to your shop.
It is widely used in SRM (Supplier Relationship Management) branch.
It depends on many factors: the traffic to your site, how often the inventory levels change, the business impact of displaing outdated data, how often the supplers allow you to call their API, their API's SLA in terms of availability and performance, and so on.
Once you have these answers, there are of course many possibilities here. For example, for a low-traffic site where getting the inventory right is important, you may want to call the 3rd-party API on every call, but revert to some alternative behavior (such as using cached data) if the API does not respond within a certain timeout.
Sometimes, well-designed APIs will include hints as to the validity period of the data. For example, some REST-over-HTTP APIs support various HTTP Cache control headers that can be used to specify a validity period, or to only retrieve data if it has changed since last request.