The local auditor reporting application presents the opinions of local auditors on local public bodies’ financial statements and conclusions on whether they have proper arrangements in place to secure value for money. The data is presented through an interactive map which allows users to explore auditor reporting for nine different types of local body and two different audit years. The interactive map also contains pop-ups to enable users to access further information about the body, such as the local auditor’s report or annual audit letter.
The application was developed using the open source programming language R and specifically through the use of the R package called Shiny. Further information about how to develop Shiny applications within R can be found at: https://shiny.rstudio.com/.
Outline of application functionality
As with most Shiny-based applications, the application comprises two key files: a server file and a user interface (UI) file.
The UI file governs the look and feel of the app as rendered on the internet. It provides users with two drop down options that allow a specific type of local body to be selected and one of three different types of audit reporting. A radio button is provided to allow users to select an audit year of interest and a further drop-down option to enable a user to zoom to the results for a particular local body. A further tab panel is provided within the app containing additional information about the different types of local auditor reporting.
The server file:
- loads the datasets that underpin the application;
- takes the user choices from the various drop downs and radio buttons in the UI;
- renders the requested output in the form of an interactive map, built using the leaflet package in R; and,
- applies a custom level of zoom and highlighting according a user’s selection in the final UI dropdown
Within the server file, these steps take place through a series of reactive shiny functions, with the appropriate dataset selected and then applied to the leaflet object, along with an appropriate legend according to user selections. Pop up functionality is also provided through the leaflet package, with the audit report links in the pop-ups referencing local copies of these documents.
The datasets used in the application consist of a series of spatial polygon data frames, providing the geographical outlines of each local body, along with their respective auditor reporting and links to the appropriate audit reports. These datasets are read into the app in .RDS format in order to improve application performance.
Separate spatial datasets are held within the application for each type of local body and each audit year and are controlled through the UI selections and server-based functions described previous.