Questions tagged [api-design]
Application Programming Interface (API) Design discusses best practises for creating libraries intended for general purpose or public use.
904
questions
335
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14answers
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Should you write your back-end as an API?
I had a heated discussion today about our MVC application. We have a website written in MVC (ASP.NET), and it usually follows the pattern of do something in the view -> hit the controller -> ...
168
votes
4answers
60k views
What is an Anti-Corruption layer, and how is it used?
I'm trying to figure out what the Anti-Corruption layer really means. I know that it's a way to transition/work around legacy code or bad APIs. What I don't understand is how it works and what makes ...
165
votes
7answers
91k views
How do searches fit into a RESTful interface?
When designing a RESTful interface, the semantics of the request types are deemed vital to the design.
GET - List collection or retrieve element
PUT - Replace collection or element
POST - Create ...
129
votes
14answers
19k views
Should the solution be as generic as possible or as specific as possible?
Say I have a entity that has "type" attribute. There could be 20+ possible types.
Now I'm asked to implement something that would allow changing the type from A->B, which is the only use case.
So ...
83
votes
5answers
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Should I return an HTTP 400 (Bad Request) status if a parameter is syntactically correct, but violates a business rule?
Say that I have a REST endpoint that takes an integer as a parameter:
/makeWaffles?numberOfWaffles=3
In this case, I want the number to be positive because I can't make a negative number of waffles (...
78
votes
8answers
60k views
RESTFul: state changing actions
I am planning to build a RESTfull API but there are some architectural questions that are creating some problems in my head. Adding backend business logic to clients is an option that I would like to ...
61
votes
3answers
18k views
Why PATCH method is not idempotent?
I was wondering about this.
Suppose I have a user resource with id and name fields.
If I want to update a field I could just do a PATCH request to the resource like this
PATCH /users/42
{"name": "...
58
votes
6answers
56k views
Many small requests vs. few large requests (API Design)
I'm currently working on a project with an organization as follows:
Client - Gets data from the main server via REST api.
Server - Requests data from various other servers via third-party APIs
Third-...
54
votes
14answers
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RESTful API design. What should I return if there are no rows?
I'm currently coding an API for a social network with the Slim Framework. My question is: What are the best practices when there are no rows to return in the json structure?
Lets say that this call /...
51
votes
10answers
14k views
What should be the http status code for “Service not available in your area” error?
Our service is in 5 cities right now. If someone tries to call our service API from any other city, we want to throw this error Service not available in your area.
The question is, what is the ...
51
votes
9answers
11k views
Should you guard against unexpected values from external APIs?
Lets say you are coding a function that takes input from an external API MyAPI.
That external API MyAPI has a contract that states it will return a string or a number.
Is it recommended to guard ...
47
votes
4answers
11k views
What's so bad about the DOM?
I keep hearing people (Crockford in particular) saying the DOM is a terrible API, but not really justifying this statement. Apart from cross-browser inconsistencies, what are some reasons why the DOM ...
47
votes
1answer
56k views
null vs missing key in REST API Response [closed]
Say in my application, some users give us their last name, and others do not. In a REST API response, which body is preferred:
With a "null" value:
{"firstName": "Bob",
"lastName": null}
Or just a ...
46
votes
3answers
44k views
REST API - Should API Return Nested JSON Objects?
When it comes to JSON APIs is it good practice to flatten out responses and avoid nested JSON objects?
As an example lets say we have an API similar to IMDb but for video games. There are a couple ...
45
votes
6answers
7k views
How necessary is it to follow defensive programming practices for code that will never be made publicly available?
I'm writing a Java implementation of a card game, so I created a special type of Collection I'm calling a Zone. All modification methods of Java's Collection are unsupported, but there's a method in ...
41
votes
8answers
134k views
Why does java.util.ArrayList allow to add null?
I wonder why java.util.ArrayList allows to add null. Is there any case where I would want to add null to an ArrayList?
I am asking this question because in a project we had a bug where some code was ...
40
votes
11answers
56k views
Should a REST API return a 500 Internal Server Error to indicate that a query references an object that does not exist?
I am working with a REST API which resides on a server that handles data for a multitude of IoT devices.
My task is to query the server using the API to collect specific performance information about ...
39
votes
1answer
3k views
How to design a REST API that can “prompt” the client about long-running operations?
Say you were to develop a REST API that provides access to a set of complex, long-running, operations.
The typical paradigm for an API like this (as I understand it) usually involves (the client) ...
39
votes
3answers
28k views
Should Microservices talk to each other?
I'm designing an application using Micro-Services and I'm unsure on the best mechanism to use to collect data from multiple services.
I believe there are two options:
Integrate an 'inter-service' ...
38
votes
6answers
7k views
Is there a pattern for handling conflicting function parameters?
We have an API function that breaks down a total amount into monthly amounts based on given start and end dates.
// JavaScript
function convertToMonths(timePeriod) {
// ... returns the given time ...
38
votes
5answers
6k views
How to describe an architectural shift that intentionally breaks REST standards?
I'm proposing changes to a very poorly architected software project that suffers from a multitude of problems. At a high level the project utilizes Angular on the front-end and consumes various REST ...
37
votes
7answers
16k views
How do I convince my boss to use REST over SOAP? [duplicate]
We need to create an API to our system. How do I convince my boss that REST is a better option than SOAP (or XML-RPC)?
I say REST is...
easier to implement and maintain
not much new to learn -- ...
37
votes
6answers
63k views
Should an HTTP API always return a body?
Is there some sort of standard regarding HTTP API responses?
After reading this discourse thread I started to wonder. We are developing our public HTTP JSON API at my work, and we do not return ...
33
votes
5answers
21k views
How does a REST API fit for a command/action based domain?
In this article the author claims that
Sometimes, it is required to expose an operation in the API that inherently is non RESTful.
and that
If an API has too many actions, then that’s an ...
31
votes
10answers
9k views
Why is Math.Sqrt() a static function?
In a discussion about static and instance methods, I always think, that Sqrt() should be a instance method of number types instead of a static method. Why is that? It obviously works on a value.
// ...
31
votes
3answers
17k views
Recommended HTTP status code for “plan limit exceeded” response
I'm designing a REST API for a project where users are always on one of several "plans" - each plan defines some resource limits, such as the max number of users an account may have or the max number ...
31
votes
4answers
8k views
Microservices and data storage
I'm considering moving a monolithic REST API to a microservice architecture, and I'm getting a bit confused about data storage.
As I see it, some of the benefits of microservices would be:
...
30
votes
2answers
41k views
REST API Design: Multiple calls vs. single call to the API
We are developing a Rest API for eCommerce website which will be consumed by mobile apps.
In the home page of an app we need to call multiple resources like Sliders, Top Brands, Best Selling Products,...
29
votes
3answers
17k views
Is there a list of common usernames to reserve in a new system?
I need to reserve usernames in my new website.
These generally fall into three categories
1) usernames no-one should have (eg: admin, user, service, help, root, etc)
2) names of super famous people ...
27
votes
7answers
12k views
Why use an opaque “handle” that requires casting in a public API rather than a typesafe struct pointer?
I'm evaluating a library whose public API currently looks like this:
libengine.h
/* Handle, used for all APIs */
typedef size_t enh;
/* Create new engine instance; result returned in handle */
int ...
27
votes
2answers
16k views
What is the best pattern for adding an existing item to a collection in REST API?
I'm designing a pragmatic REST API and I'm a little stuck on how best to add existing entities to a collection. My domain model includes a Project that has a collection of Sites. This is a strict many-...
26
votes
3answers
6k views
RESTful API: HTTP verbs with shared or specific URLs?
While creating a RESTful API, should I use HTTP Verbs on the same URL (when it's possible) or should I create an specific URL per action?
For example:
GET /items # Read all items
GET /...
26
votes
3answers
45k views
Is it OK to return HTML from a JSON API?
On my current project I am responsible for the implementation of a service which involves the consumption of newly created RESTful APIs, documented as solely supporting JSON.
The client consistently ...
26
votes
5answers
30k views
How best do you represent a bi-directional sync in a REST api?
Assuming a system where there's a Web Application with a resource, and a reference to a remote application with another similar resource, how do you represent a bi-directional sync action which ...
25
votes
4answers
2k views
When creating an api should I stick with small functions and many calls, or a few calls and large functions?
I have a rails platform that I maintain. It has a lot of different web applications built on top of it. However now a client is asking for an API so that they can keep users on their site, but take ...
25
votes
2answers
17k views
Should I make up my own HTTP status codes? (a la Twitter 420: Enhance Your Calm)
I'm currently implementing an HTTP API, my first ever.
I've been spending a lot of time looking at the Wikipedia page for HTTP status codes, because I'm determined to implement the right codes for ...
25
votes
10answers
6k views
API design: concrete vs. abstract approach - best practices?
When discussing APIs between systems (on the business level) there are often two different point of views in our team: some people prefer a more - lets say - generic abstract approach, other a ...
24
votes
5answers
26k views
Function returning true/false vs. void when succeeding and throwing an exception when failing
I'm building an API, a function that uploads a file. This function will return nothing/void if the file was uploaded correctly and throws an exception when there was some problem.
Why an exception ...
23
votes
3answers
11k views
When should I use string_view in an interface?
I'm using an internal library that was designed to mimic a proposed C++ library, and sometime in the past few years I see its interface changed from using std::string to string_view.
So I dutifully ...
21
votes
9answers
6k views
Declaring that a function never returns
If I have a function that never returns (it contains an infinite loop) how do I declare/communicate that it will never return to the user of the function?
The user does not see the source code, only ...
20
votes
8answers
2k views
“Public APIs are forever: Only one chance to get it right”?
In an OS book I just read that, "Public APIs are forever: Only one chance to get it right". Is it true? Is it applicable only in APIs of Operating Systems or other APIs too? For example, will this be ...
20
votes
2answers
2k views
Should one always know what an API is doing just by looking at the code?
Recently I have been developing my own API and with that invested interest in API design I have been keenly interested how I can improve my API design.
One aspect that has come up a couple times is (...
19
votes
4answers
7k views
Why does the Java collections APIs not have a last method? [closed]
This is for ordered collections e.g. java.util.List. Why did the language designers not include a last method? The only reasons I can think of are:
ambiguity when the collection is empty (return null ...
18
votes
4answers
609 views
Database abstraction — is it being overdone?
After being exposed to numerous database abstraction layers, I'm starting to wonder what the point is of every library inventing their own different paradigm to access data. Picking up a new DAL feels ...
asked Apr 15 '11 at 19:21
Note to self - think of a name
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17
votes
4answers
5k views
Why doesn't Java String have static string manipulation methods?
Why didn't Java designers create static versions of string manipulation methods in the java.lang.String class? The following methods are what I refer to, but the question can be extended to other non-...
17
votes
3answers
2k views
Detecting IEnumerable “State Machines”
I just read an interesting article called Getting too cute with c# yield return
It made me wonder what the best way is to detect whether an IEnumerable is an actual enumerable collection, or if it's a ...
17
votes
1answer
12k views
RESTful API and i18n: how to design the response?
We are designing a RESTful API that is mainly intended to meet the needs of a single client. Because of its very particular circumstances, this client has to make as few requests as possible.
The ...
16
votes
2answers
15k views
When to use nested resources in a RESTful API
I have two resources: users and links.
Users can have several links associated with them. I have designed my RESTful API so that you can reach the links associated with a user at the following URI:
/...
15
votes
3answers
3k views
Versioning REST APIs. Each API has its own version
It's very common to specify the version of REST APIs in the URL, specifically at the beginning of path, i.e. something like:
POST /api/v1/accounts
GET /api/v1/accounts/details
However, I haven't ...
15
votes
6answers
1k views
What do great APIs have in common? [closed]
What is it about great APIs that makes them great? I think that adhering to the "do one thing and do it well" mantra is a good sign and being is a good mapping to the problem domain is important, but ...
