The Builder

The Connector Builder is implemented as an extension for the Firefox web-browser, and requires a version in the 3.x series. Because of its tight integration with the browser, porting the Builder to IE, Sarafi, Chrome or Opera would be a significant undertaking – most likely not possible at all for some of these browsers, as they do not all make the same facilities available to extensions.

There are two ways to install the Builder: most users will install from a .xpi file, the standard packaging for Firefox extensions. The most recent release of this can be obtained from Index Data – email us for details. Developers and others who need the bleeding-edge version of the Builder can check out the source code and modify their Firefox configuration by hand to run the extension directly from the source. This is done by adding a file named to the extension directory, containing only a single line that specifies the directory holding the Builder source-code: for example /usr/local/src/git/cf/builder (depending on where the source was checked out). The location of the extension directory is different on different platforms – for example, on MacOS X, the global extensions area is /Applications/Firefox.app/Contents/MacOS/extensions/

When running Firefox in a configuration that includes the Builder extension, the browser can be used normally, invoking the Builder only when required. It can be brought up by choosing View → Sidebar → Connector Framework: Builder.

When the Builder is active, the browser is split into two vertical columns. On the left is the Builder; the right column contains the old contents of the browser window. Its contents are unchanged, and all the navigation buttons (Back, Forwards, Reload, Home, etc.) work as usual on it. The Builder does not impinge on the normal use of the browser.

The builder itself is split vertically into three main areas: at the top, and area concerned with the current task; below that, a list of the steps that make up that task; and below that, a display of results generated by the last connector run. Slider bars between these sections adjust the amount of vertical space allotted.

In more detail, top from to bottom, the Builder presents:

• A title bar showing the name cfBuilder and a close button.

• A toolbar containing buttons to create a new connector, load an existing connector, save the current connector or save it as a new file, add a task, remove a task, edit the connector’s metadata, go to the connector repository’s administrative home, or upload the current connector to the repository. These operations will be discussed in more detail below.

• A dropdown for selecting which task to work on. Nearly all connectors have Search, Parse and Next tasks; others can be added, notably Init.

• A list of the selected task’s arguments. For example, Search tasks have arguments for the various fields they might search, and Init tasks have arguments for the username and password that can be used in authentication. When a connector is run as part of a searching solution, values for these arguments are submitted at run-time (e.g. the query terms); the Builder allows example values to be saved, for use when running the connector while developing it.

• A toolbar containing buttons that relate to steps within the selected task: with these, it is possible to add a step after the currently selected one, delete the current step, move it up or down the list, run the current step in isolation, or run the whole sequence of step that make up the task. These operations will be discussed in more detail below.

• The list of the actual steps, showing for each step its type (in bold), a summary of its configuration (in normal font), and an indication of whether or not it is an Alt step (i.e. one that is run when and only when the step before it fails).

• An area containing the results generated by running steps of the selected task. For Search tasks, this is typically a single number, the hit-count; for Parse tasks, it is a list of records, each containing multiple fields.

• An area for creating and running tests for the current task. At present, this requires providing paths through the result structure and regular expressions that the contents of those paths must match.

• Finally, a status line indicates whether or not the connector is considered complete, and if not provides a link to a popup that shows which tasks are missing.