Customize JSON Responses

This page has moved to docs.servicestack.net/customize-json-responses

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The JSON Responses for all ServiceStack Services can be configured Globally, individually per-Service or customized per-request by the client using the ?jsconfig QueryString modifier.

Global Default JSON Configuration

ServiceStack uses the ServiceStack.Text Serializers for its built-in JSON/JSV and CSV serialization. The serialization can be customized globally by configuring the JsConfig or type-specific JsConfig<T> static classes with your preferred defaults, e.g:

public override void Configure(Container container)
{
    JsConfig.EmitLowercaseUnderscoreNames = true; 
    JsConfig.ExcludeDefaultValues = true;

    JsConfig<Guid>.SerializeFn = guid => guid.ToString("D");
    JsConfig<TimeSpan>.SerializeFn = time => 
        (time.Ticks < 0 ? "-" : "") + time.ToString("hh':'mm':'ss'.'fffffff");
}

Customize JSON Responses in Service

The Global Defaults can be overridden on a adhoc basis by returning your Response DTO in a custom HttpResult configured with a custom JS Config Scope, e.g:

return new HttpResult(responseDto) {
    ResultScope = () => JsConfig.With(
        emitLowercaseUnderscoreNames:true, excludeDefaultValues:true)
};

Customize JSON Responses from Client

The JSON and JSV Responses for all Services (inc. Auto Query Services) can also be further customized with the new ?jsconfig QueryString param which lets your Service consumers customize the returned JSON Response to their preference. This works similar to having wrapped your Service response in a HttpResult with a Custom ResultScope in the Service implementation to enable non-default customization of a Services response, e.g:

/service?jsconfig=EmitLowercaseUnderscoreNames,ExcludeDefaultValues

Works similarly to:

return new HttpResult(new { TheKey = "value", Foo=0 }) {
    ResultScope = () => JsConfig.With(
        emitLowercaseUnderscoreNames:true, excludeDefaultValues:true)
};

Which results in lowercase_underscore key names with any properties with default values removed:

{"the_key":"value"}

It also supports cascading server and client ResultScopes, with the client ?jsconfig taking precedence.

Nearly all JsConfig scope options are supported other than delegates and complex type configuration properties.

Camel Humps Notation

JsConfig also supports Camel Humps notation letting you target a configuration by just using the Uppercase Letters in the property name which is also case-insensitive so an equivalent shorter version of the above config can be:

?jsconfig=ELUN,edv

Camel Humps also works with Enum Values so both these two configurations are the same:

?jsconfig=DateHandler:UnixTime
?jsconfig=dh:ut

Custom JSON Live Example

AutoQuery Viewer makes use of this feature in order to return human readable dates using the new ISO8601DateOnly DateHandler Enum Value as well as appending ExcludeDefaultValues when specifying custom fields so that any unpopulated value type properties with default values are excluded from the JSON Response. Here's a live example of this comparing the default Response with the customized JSON Response:

• http://github.servicestack.net/repos.json?fields=Name,Homepage,Language,Updated_At
• http://github.servicestack.net/repos.json?fields=Name,Homepage,Language,Updated_At&jsconfig=edv,dh:iso8601do

Custom JSON Settings

The presence of a bool configuration property will be set to true unless they have a false or 0 value in which case they will be set to false, e.g:

?jsconfig=ExcludeDefaultValues:false

For a quick reference the following bool customizations are supported:

Name	Alias
EmitCamelCaseNames	eccn
EmitLowercaseUnderscoreNames	elun
IncludeNullValues	inv
IncludeNullValuesInDictionaries	invid
IncludeDefaultEnums	ide
IncludePublicFields	ipf
IncludeTypeInfo	iti
ExcludeTypeInfo	eti
ConvertObjectTypesIntoStringDictionary	cotisd
TreatEnumAsInteger	teai
TryToParsePrimitiveTypeValues	ttpptv
TryToParseNumericType	ttpnt
ThrowOnDeserializationError	tode
EscapeUnicode	eu
PreferInterfaces	pi
SkipDateTimeConversion	sdtc
AlwaysUseUtc	auu
AssumeUtc	au
AppendUtcOffset	auo
DateHandler (dh)
TimestampOffset	to
DCJSCompatible	dcjsc
ISO8601	iso8601
ISO8601DateOnly	iso8601do
ISO8601DateTime	iso8601dt
RFC1123	rfc1123
UnixTime	ut
UnixTimeMs	utm
TimeSpanHandler (tsh)
DurationFormat	df
StandardFormat	sf
PropertyConvention (pc)
Strict	s
Lenient	l

Create Custom Scopes using String config

You can also create a scope from a string manually using JsConfig.CreateScope(), e.g:

using (JsConfig.CreateScope("EmitLowercaseUnderscoreNames,ExcludeDefaultValues,dh:ut")) 
{
    var json = dto.ToJson();
}

If you don't wish for consumers to be able to customize JSON responses this feature can be disabled with Config.AllowJsConfig=false.