Problem

Content-Type: "application/problem+json" or "application/problem+xml"

Iris has builtin support for the Problem Details for HTTP APIs.

The Context.Problem method sends a JSON or XML problem response. Behaves exactly like Context.JSON but with default ProblemOptions.JSON indent of two spaces (" ") and a response content type of "application/problem+json" instead.

Problem(v interface{}, opts ...ProblemOptions) (int, error)

The ProblemOptions looks like that:

// ProblemOptions the optional settings when server replies with a Problem.
// See `Context.Problem` method and `Problem` type for more details.
type ProblemOptions struct {
// JSON are the optional JSON renderer options.
JSON JSON
// RenderXML set to true if want to render as XML doc.
// See `XML` option field too.
RenderXML bool
// XML are the optional XML renderer options.
// Affect only when `RenderXML` field is set to true.
XML XML
// RetryAfter sets the Retry-After response header.
// https://tools.ietf.org/html/rfc7231#section-7.1.3
// The value can be one of those:
// time.Time
// time.Duration for seconds
// int64, int, float64 for seconds
// string for duration string or for datetime string.
//
// Examples:
// time.Now().Add(5 * time.Minute),
// 300 * time.Second,
// "5m",
// 300
RetryAfter interface{}
// A function that, if specified, can dynamically set
// retry-after based on the request. Useful for ProblemOptions reusability.
// Should return time.Time, time.Duration, int64, int, float64 or string.
//
// Overrides the RetryAfter field.
RetryAfterFunc func(Context) interface{}
}

Use the options.RenderXML and XML fields to change this behavior and send a response of content type "application/problem+xml" instead.

func newProductProblem(productName, detail string) iris.Problem {
return iris.NewProblem().
// The type URI, if relative it automatically convert to absolute.
Type("/product-error").
// The title, if empty then it gets it from the status code.
Title("Product validation problem").
// Any optional details.
Detail(detail).
// The status error code, required.
Status(iris.StatusBadRequest).
// Any custom key-value pair.
Key("productName", productName)
// Optional cause of the problem, chain of Problems.
// .Cause(other iris.Problem)
}
func fireProblem(ctx iris.Context) {
response := newProductProblem("product name", "problem details")
options := iris.ProblemOptions{
JSON: iris.JSON{
Indent: " ",
},
RetryAfter: 300,
}
ctx.Problem(response, options)
}

Outputs "application/problem+json"

{
"type": "https://host.domain/product-error",
"status": 400,
"title": "Product validation problem",
"detail": "problem error details",
"productName": "product name"
}

When RenderXML is set to true then the response will look be rendered as XML instead.

Outputs "application/problem+xml"

<Problem>
<Type>https://host.domain/product-error</Type>
<Status>400</Status>
<Title>Product validation problem</Title>
<Detail>problem error details</Detail>
<ProductName>product name</ProductName>
</Problem>