server.R and ui.R need to be refactored for correctness and readability

[bryce-carson]

The server and UI code is chaotic and not written in a clear style using the syntax of R to its fullest. The server and UI code needs to be refactored so that it is more maintainable after I leave the project.

spatialEpisim/server.R

Lines 846 to 865 in df70041

	if(input$modelSelect == "SEIRD"){
	if (input$selectedCountry == "Czech Republic"){
	lambdaValue <- as.numeric(filter(epiparms, ISONumeric == "CZE" & model == "SEIRD")[1,"lambda"])
	} else if (input$selectedCountry == "Nigeria"){
	lambdaValue <- as.numeric(filter(epiparms, ISONumeric == "NGA" & model == "SEIRD")[1,"lambda"])}
	else if (input$selectedCountry == "Uganda"){
	lambdaValue <- 5}
	else if (input$selectedCountry == "Democratic Republic of Congo"){
	lambdaValue <- as.numeric(filter(epiparms, ISONumeric == "COD" & model == "SEIRD")[1,"lambda"])}
	} else if (input$modelSelect == "SVEIRD"){
	if (input$selectedCountry == "Czech Republic"){
	lambdaValue <- as.numeric(filter(epiparms, ISONumeric == "CZE" & model == "SVEIRD")[1,"lambda"])
	} else if (input$selectedCountry == "Nigeria"){
	lambdaValue <- as.numeric(filter(epiparms, ISONumeric == "NGA" & model == "SVEIRD")[1,"lambda"])
	}
	else if (input$selectedCountry == "Uganda"){
	lambdaValue <- as.numeric(filter(epiparms, ISONumeric == "COD" & model == "SVEIRD")[1,"lambda"])}
	else if (input$selectedCountry == "Democratic Republic of Congo"){
	lambdaValue <- as.numeric(filter(epiparms, ISONumeric == "COD" & model == "SVEIRD")[1,"lambda"])}
	}

If the names of the countries are added as a new column to the epiparms data file, these lines can be simplified to the following pipeline.

lambdaValue <-
filter(epiparms, model == input$modelSelect, country == input$selectedCountry)[1, "lambda"] |>
as.numeric()

[bryce-carson]

This is just an example of what can be improved in server.

[bryce-carson]

This is just an example of what can be improved in server.

To justify this issue being an example I am labelling it duplicate of the less specific #32 which represents the needed work to refactor the entire application architecture and implementation.

[bryce-carson]

I removed the duplicate label and renamed the issue to make it clearer that this issue was originally opened to track the refactoring of the server and UI code. At the time I opened this issue I was unaware that the contents of the R/ sub-folder would need to be refactored as well, so this issue tracks a separate but linked refactoring.

The server code will take advantage of the functionality provided by the functions defined in one or more files in the R/ sub-folder, so this issue is related to the refactoring occurring in #32 in that way and they will be closed at the same time when the unstable branch is merged in to main.

[bryce-carson]

As of today

Before

[bryce@fedora]~/Documents/src/r/spatialEpisim% scc --no-cocomo ~/src/r/spatialEpisim.stable/server.R 
───────────────────────────────────────────────────────────────────────────────
Language                 Files     Lines   Blanks  Comments     Code Complexity
───────────────────────────────────────────────────────────────────────────────
R                            1       792      129        53      610         84
───────────────────────────────────────────────────────────────────────────────
Total                        1       792      129        53      610         84
───────────────────────────────────────────────────────────────────────────────
Processed 28001 bytes, 0.028 megabytes (SI)
───────────────────────────────────────────────────────────────────────────────

After

[bryce@fedora]~/Documents/src/r/spatialEpisim% scc --no-cocomo server.R                             
───────────────────────────────────────────────────────────────────────────────
Language                 Files     Lines   Blanks  Comments     Code Complexity
───────────────────────────────────────────────────────────────────────────────
R                            1       614       86        81      447         50
───────────────────────────────────────────────────────────────────────────────
Total                        1       614       86        81      447         50
───────────────────────────────────────────────────────────────────────────────
Processed 23659 bytes, 0.024 megabytes (SI)
───────────────────────────────────────────────────────────────────────────────