Components of an adaptor
Last updated
Last updated
Behind the scenes, an adaptor consists of a JavaScript function and a metadata manifest, wrapped up and presented in a graphical format in the Data-flo interface.
In the interface, the entire adaptor is portrayed as a card (or step in the data-flo, or box), and the metadata manifest is portrayed as arguments.
An adaptor's arguments are variables that affect the adaptor's outcome. They define the specifics of the Javascript function underlying the adaptor, allowing the adaptor to transform data. Each argument is portrayed on the adaptor card by a radio button, or socket.
On the left side of the card are inputs (arguments representing information the user needs to define to complete the adaptor function). Many arguments have a default value that will be used if nothing else is specified, but input arguments without default values require definition -- these are marked with an asterix/star (see example below)
On the right side of the card are outputs (the data and/or any other information resulting from the adaptor function).
Each argument has a pre-defined **** data type, which is relevant for connecting adaptors to each other (also known as Binding to another transformation)
In this "Select columns" adaptor, the output data contains the input data for all the columns specified in the columns input argument.
Entering the name of an output file is still an input argument, because the user is inputting the filename.