Service-Defaults Reference

The service-defaults section of the Gateway configuration file allows you to configure default values that apply to all services running on the Gateway.

Overview

Use the optional service-defaults element to configure certain default options across all services running on the Gateway. However, note that any elements you specify in individual services (that you configure in the service section of the Gateway configuration file) override the defaults you specify in the service-defaults section of the Gateway configuration file. For example, if there are no explicit accept-options configured for a particular service, then the Gateway uses the values configured in service-defaults.

Structure

The Gateway configuration file (gateway-config.xml) defines the service-defaults configuration element contained in the top-level gateway-config element:

gateway-config
- service-defaults
  - accept-options
    - . . . (Listed in the Service Reference)
  - connect-options
    - . . . (Listed in the Service Reference)
  - mime-mapping
    - . . . (Listed in the Service Reference)

service-defaults

Each service-defaults element can contain any of the following subordinate elements:

Subordinate Element	Description
accept-options	Use the `accept-options` element to add options that apply to all services on the Gateway. The complete list of `accept-options` are fully documented in the Service Reference.
connect-options	Use the `connect-options` element to add options that apply to all services on the Gateway. The complete list of `connect-options` are fully documented in the Service Reference.
mime-mapping	Use the `mime-mappings` element to define the way the Gateway maps a file extension to a MIME type. Each `mime-mapping` entry defines the HTTP Content-Type header value to be returned when a client or browser requests a file that ends with the specified extension. The `service-defaults` section in the default Gateway configuration file contains default MIME type mappings that apply to all services on the Gateway. The complete list of `mime-mapping` extensions and `mime-type`’s are documented in the Service Reference.

Example of setting default accept-options

The following example shows ssl.encryption disabled, sample network protocol bindings, ws.maximum.message.size set to 256k, and http.keepalive.timeout set to 90 seconds, just above the default mime-mapping entries. Note that wss and https can both be bound to the same port (8055) because they are compatible protocols. However, if you try to bind incompatible protocols to the same port, you will receive a port conflict error when the Gateway starts up. For instance, you cannot bind ws and https to the same port.

<service-defaults>
  <accept-options>
    <ssl.encryption>disabled</ssl.encryption>
    <ws.bind>8050</ws.bind>
    <wss.bind>192.168.10.25:8055</wss.bind>
    <http.bind>192.168.10.25:8060</http.bind>
    <https.bind>192.168.10.25:8055</https.bind>
    <ws.maximum.message.size>256k</ws.maximum.message.size>
    <http.keepalive.timeout>90 seconds</http.keepalive.timeout>
  </accept-options>

  <mime-mapping>
    <extension>html</extension>
    <mime-type>text/html</mime-type>
  </mime-mapping>
  ...
  </service-defaults>

Example of Mime Mapping

A service can return files of various types to a client. Generally, HTTP mandates that a response containing a file also specify a Content-Type header describing the file contents. You may use a tag to specify the Content-Type value to be returned for files with a particular name extension.

The following example shows two entries for the same file extension; in this case, when the Gateway receives a request for a file with an HTML extension, the Gateway will respond with a Content-Type header value of text/html (not image/png). This example indicates that for files with names ending in ‘.png’, the header ‘Content-Type: image/png’ should be returned by the Gateway, and ‘Content-Type: text/html’ should be returned for .html files. You can specify mappings in the both the service-defaults block and in any service blocks. If a mapping for a given extension is specified in both the service-defaults block and a service block, the service-level mapping will be used when providing files from that service.

  <mime-mapping>
    <extension>html</extension>
    <mime-type>image/png</mime-type>
  </mime-mapping>
  <mime-mapping>
    <extension>js</extension>
    <mime-type>text/javascript</mime-type>
  </mime-mapping>
  <mime-mapping>
    <extension>html</extension>
    <mime-type>text/html</mime-type>
  </mime-mapping>

Notes

When the Gateway responds to a file request, such as from the directory service, the response includes a Content-Type header based on the filename extension of the requested file. The Content-Type header value is the specified MIME type for that extension. If the file extension is not mapped to a MIME type by a mime-mapping element, the Gateway does not include a Content-Type header in its response.
You can specify MIME types for file extensions either in the service-defaults section or in a service. Specifying MIME types for file extensions in a service overrides any existing corresponding mime-mapping entries in the service-defaults section. See service for more information.
If you specify two or more mime-mapping entries for the same extension in a single service or in service-defaults, the Gateway only applies the last mime-mapping entry for that extension.

The service-defaults section in the default Gateway configuration includes the following standard mappings. You can modify these entries, but keep in mind that all mime-mapping entries must come after any accept-options you add to this section.

Note: The Gateway has hard-coded internal MIME mappings that are equivalent to those provided in the service-defaults section of the gateway-config.xml, for backward compatibility with earlier releases of Kaazing Gateway. You can edit these mappings, as needed (to override them with new MIME-type values), but you cannot remove the initial internal set of mappings.

The default Gateway mime-mapping entries are:

<service-defaults>
  <mime-mapping>
    <extension>html</extension>
    <mime-type>text/html</mime-type>
  </mime-mapping>
  <mime-mapping>
    <extension>htm</extension>
    <mime-type>text/html</mime-type>
  </mime-mapping>
  <mime-mapping>
    <extension>js</extension>
    <mime-type>text/javascript</mime-type>
  </mime-mapping>
  <mime-mapping>
    <extension>png</extension>
    <mime-type>image/png</mime-type>
  </mime-mapping>
  <mime-mapping>
    <extension>gif</extension>
    <mime-type>image/gif</mime-type>
  </mime-mapping>
  <mime-mapping>
    <extension>jpg</extension>
    <mime-type>image/jpeg</mime-type>
  </mime-mapping>
  <mime-mapping>
    <extension>jpeg</extension>
    <mime-type>image/jpeg</mime-type>
  </mime-mapping>
  <mime-mapping>
    <extension>svg</extension>
    <mime-type>image/svg+xml</mime-type>
  </mime-mapping>
  <mime-mapping>
    <extension>css</extension>
    <mime-type>text/css</mime-type>
  </mime-mapping>
  <mime-mapping>
    <extension>htc</extension>
    <mime-type>text/x-component</mime-type>
  </mime-mapping>
  <mime-mapping>
    <extension>jnlp</extension>
    <mime-type>application/x-java-jnlp-file</mime-type>
  </mime-mapping>
  <mime-mapping>
    <extension>manifest</extension>
    <mime-type>text/cache-manifest</mime-type>
  </mime-mapping>
  <mime-mapping>
    <extension>appcache</extension>
    <mime-type>text/cache-manifest</mime-type>
  </mime-mapping>
  <mime-mapping>
    <extension>vtt</extension>
    <mime-type>text/vtt</mime-type>
  </mime-mapping>
  <mime-mapping>
    <extension>aspx</extension>
    <mime-type>text/html</mime-type>
  </mime-mapping>
  </service-defaults>

Summary

In this document, you learned about the Gateway service-defaults configuration element and how to specify it in your Gateway configuration file. For more information about the location of the configuration files and starting the Gateway, see Setting Up the Gateway. For more information about Kaazing Gateway administration, see the documentation.