Difference between revisions of "Defining New Protocol"

Latest revision as of 21:11, 22 July 2008

General

This article demonstrate the way to extend Eiffel Information System (EIS) within EiffelStudio to support more protocols. To support a new protocol in EiffelStudio, the only thing to do is to provide a new Help Provider.

Steps to Create a New Help Provider

Inherit ES_EIS_ENTRY_HELP_PROVIDER

• Create your own help provider which inherits from {ES_EIS_ENTRY_HELP_PROVIDER}.
• Implement `document_protocol' and `document_description'.

Existing sample:

document_protocol: !STRING_32
			-- Document protocol used by a URI to navigate to the help accessible from the provider.
		once
			create Result.make_empty
			Result.append ("PDF")
		end
 
	document_description: !STRING_32
			-- Document short description
		once
			create Result.make_empty
			Result.append ("PDF")
		end

• Redefine `show_help'. `show_help' does all works to analyze the EIS entry node and perform required behaviors accordingly.
  • One can object test against `a_section', and get the instance of {HELP_SECTION_EIS_ENTRY} from which {EIS_ENTRY} is available. In {EIS_ENTRY}, basic attributes such as name, tags, source and so on are available, as well as extended elements that are stored in `others' which maybe needed by the new protocol.
  • In this circumstance, `a_context_id' is always the name of current EIS entry.
  • `format_uris' is available to expand a `source' to support variables described at HERE.
  • `launch_uri' is available to launch a URI in a web browser.
  • One needs to implement specific launcher if he wants the source to be opened in specific tools.

Adding a New Kind of Help Provider

All known kinds of help providers should be written in class {HELP_PROVIDER_KINDS}. An instance of {UUID} and a string of that uuid are needed in the class. Existing example:

...
	frozen pdf: !UUID
			-- PDF help system
		once
			create Result.make_from_string (pdf_uuid_string)
		end
...
	pdf_uuid_string: !STRING_8		= "BA35A9BB-5B69-4BD3-88B3-FB8DAE5CA08E"
...

Registering Help Provider

Doing this to make the system really take the new protocol into account. Added a line at {ES_SERVICE_INITIALIZER}.register_help_provider This is an existing example:

 a_service.register_provider (l_kinds.pdf, {PDF_HELP_PROVIDER})