Sagar Ganatra's Blog

I was experimenting with a new method 'onAbort' introduced in ColdFuion 10 which can be defined in an Application.cfc file. This method is invoked when cfabort is called. What if showerror attribute is also present in the cfabort tag? Would it still invoke the onAbort method and then onError? The onAbort method would be ignored and the onError method would be invoked. Even in a case wherein the onError method is not defined in Application.cfc, the onAbort method wouldn't be invoked. In this case the error message would be shown on the standard error template.

There are various complex types in ColdFusion – Array, Struct, Query. When a REST service in ColdFusion returns one of these complex types, it has to be serialized to either JSON or XML format. As explained in my previous post , the HTTP protocol can be used in content type negotiation. You can specify the desired content type either by specifying it at the end of the URL or in the Accept header of HTTP request. In this post, I’ll explain the format in which the complex types are returned from a ColdFusion REST service.

Prior to ColdFusion 10, to write or append to a file one had to specify the file content in the output attribute of CFFILE tag. In ColdFusion 10, you can specify the file content in the body of the cffile tag. In cases where the file content is specified in body as well as in the output attribute, the output attribute would be ignored.

In ColdFusion 10, you can now show the users location on a Google map created with the CFMAP tag. The CFMAP and CFMAPITEM tags now have a boolean attribute showuser . When set to true the browser would ask for the users permission and then display users geo-location on the map. This is now supported in most of the modern browsers. In cases where the browser doesn’t support Geo-location API then the values provided in centeraddress or centerlatitude\centerlongitude attributes will be used to add a marker in the Google map.

Following with my previous post on how content negotiation between the client and server help in invoking an appropriate REST service. In this post I’ll explain how one can specify multiple mime types in the request header and also the quality factor that enables server to decide which mime type to serve for the incoming request. The client sends a HTTP request to the Server along with several headers, one of them is the Accept header. The Accept header can contain a list of mime types that the client (user agent) is willing to process. These mime types are separated by a comma and may optionally be combined with the quality factor. A CFC can contain several methods with produces attribute set to a specific mime type. The Accept header may contain several mime types: text/html, text/plain, application/xml, application/json, */* Server would parse the Accept header and will search for a REST service that matches the mime type specified first in the Accept header list. In this cas

The HTTP protocol provides a Content negotiation mechanism using which different formats of the document can be served using the same URI. For example, a JavaScript application can request the content in JSON format and an external system say a Java client can request for the same content in XML format. Here the clients need to specify the content format in the Accept attribute of the HTTP request. The REST service can specify the format in which the data will be returned to the client in ‘produces’ attribute.

As mentioned in my earlier post there are various ways in which data can passed to a REST service. The cfargument tag has a new attribute restargsource, it can take one of these values – path, query, matrix, form, cookie and header.

In my previous post, I’d explained how REST services can be created, published and accessed in ColdFusion 10 . Andy , asked me “Is there any way to avoid having the /rest/restapp/ in the URL?”. In short Yes. ‘rest’ in the URL lets the ColdFusion Server know that the incoming request is for a REST service. As mentioned in my previous post, you can update the servlet mapping defined in web.xml located at cfusion_home\wwwroot\WEB-INF directory. But it can't be avoided. Coming to the ‘restapp’ in the URL which indicates the Application name or the Servlet mapping. It can be removed from the URL by placing the CFCs in a default directory. While registering a REST service in the ColdFusion Administrator, there is an option to set the service as a default service, meaning all the CFCs placed in the directory would not require the Application name or Service mapping to be provided in the URL.