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Expanded Audience – Frontegg – Security (partner)
announcement - icon User management is very complex, when implemented properly. No surprise here.

Not having to roll all of that out manually, but instead integrating a mature, fully-fledged solution - yeah, that makes a lot of sense.
That's basically what Frontegg is - User Management for your application. It's focused on making your app scalable, secure and enjoyable for your users.
From signup to authentication, it supports simple scenarios all the way to complex and custom application logic.

Have a look:

>> Elegant User Management, Tailor-made for B2B SaaS

NPI – Spring Top – Temp – Non-Geo (Lightrun)

Get started with Spring 5 and Spring Boot 2, through the reference Learn Spring course:

NPI – Lightrun – Spring (partner)

We rely on other people’s code in our own work. Every day. It might be the language you’re writing in, the framework you’re building on, or some esoteric piece of software that does one thing so well you never found the need to implement it yourself.

The problem is, of course, when things fall apart in production - debugging the implementation of a 3rd party library you have no intimate knowledge of is, to say the least, tricky. It’s difficult to understand what talks to what and, specifically, which part of the underlying library is at fault.

Lightrun is a new kind of debugger.

It's one geared specifically towards real-life production environments. Using Lightrun, you can drill down into running applications, including 3rd party dependencies, with real-time logs, snapshots, and metrics. No hotfixes, redeployments, or restarts required.

Learn more in this quick, 5-minute Lightrun tutorial:

>> The Essential List of Spring Boot Annotations and Their Use Cases

1. Overview

Swagger is a set of specifications to document and describe REST APIs. It also provides example values for the endpoint parameters.

In this tutorial, we'll show how to produce a default example value for String arrays, as this behavior is not enabled by default.

2. Specify an Array of Strings as Body Parameters in Swagger

The issue arises when we want to specify an array of strings as body parameters in Swagger.

Swagger's default Example Value is a bit opaque, as we can see in the Swagger editor:

swagger description array without example 1

So, here we see that Swagger doesn't really show an example of what the array contents ought to look like. Let's see how to add one.


Firstly, we start by specifying the array of strings in Swagger using YAML notation. In the schema section, we include type: array with items String.

To better document the API and instruct the user, we can use the example label of how to insert values:

  - in: body
    description: ""
    required: true
    name: name
      type: array
        type: string
      example: ["str1", "str2", "str3"]

Let's see how our display is now more informative:

swagger description array 1

4. Springfox

Or, we can achieve the same outcome using Springfox.

We need to use the dataType and example in the data model with @ApiModel and @ApiModelProperty annotations:

public class Foo {
    private long id;
    @ApiModelProperty(name = "name", dataType = "List", example = "[\"str1\", \"str2\", \"str3\"]")
    private List<String> name;

After that, we also need to annotate the Controller to let Swagger point to the data model.

So, let's use @ApiImplicitParams for that:

@RequestMapping(method = RequestMethod.POST, value = "/foos")
@ApiImplicitParams({ @ApiImplicitParam(name = "foo", 
  value = "List of strings", paramType = "body", dataType = "Foo") })
public Foo create(@RequestBody final Foo foo) {

And that's it!

5. Conclusion

When documenting the REST APIs, we may have parameters that are string arrays. Ideally, we'd document these with Example Values.

We can do this in Swagger with the example property. Or, we can use the example annotation attribute in Springfox.

As always, the code is available over on GitHub.

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