---
title: "Getting Started with {golem}"
author: "Colin Fay"
date: "`r Sys.Date()`"
output: rmarkdown::html_vignette
vignette: >
  %\VignetteIndexEntry{a_start}
  %\VignetteEngine{knitr::rmarkdown}
  %\VignetteEncoding{UTF-8}
---

<script type="text/javascript">
$(document).ready(function () {
  window.initializeCodeFolding("show" === "show");
});
</script>

```{r setup, include = FALSE}
knitr::opts_chunk$set(
  collapse = TRUE,
  comment = "#>", 
  eval = FALSE
)
```

## Installing {golem}

+ You can install the stable version of `{golem}` from CRAN:

``` {r}
install.packages("golem")
```


The development version of `{golem}` can be installed from GitHub using the `{remotes}` package: 

```{r}
remotes::install_github("Thinkr-open/golem")
```

## Getting started 

Note before using `{golem}`: 

- A `{golem}` app is contained inside a package, so knowing how to build a package is highly recommended. On the plus side, everything you know about package development can be reused in `{golem}`.

- A `{golem}` app works better if you are working with `shiny modules`, so knowing how modules work is recommended, but not mandatory. 

In the rest of the Vignettes, we'll assume you're working in RStudio. 

### Create a package

Once the package is installed, you can got to File > New Project... in RStudio, and choose "Package for Shiny App Using golem" input. 

```{r, echo=FALSE, out.width="80%", fig.align="center", eval=TRUE}
knitr::include_graphics("golemtemplate.png")
```


If you want to do it through command line, you can use:

```{r}
golem::create_golem(path = "path/to/package")
```

```{r include = FALSE, eval = TRUE, error = TRUE}
x <- fs::path(tempdir(), "golex")
try(fs::dir_delete(x), silent = TRUE)
golem::create_golem(path = x, package_name = "golex", open = FALSE)
```

This command allows you to create "illegally-named" package (for example, `1234`) by passing the `check_name` argument to `FALSE`. Note that this is not recommended and __should only be done if you know what you are doing__. 

Once you've got that, a new RStudio project will be launched. Here is the structure of this project:

```{r echo = FALSE, eval = TRUE}
z <- capture.output( fs::dir_tree(x))
z <- z[-1]
w <- lapply(
  z, function(x){
    cat(x, "\n")
  }
)
```


If you're already familiar with R packages, most of these files will seem very familiar to you. That's because a `{golem}` app IS a package.

+ `DESCRIPTION` & `NAMESPACE`: Package meta-data.

+ `R/app_config.R`: Used to read inside `{golem}` config file located at `inst/golem-config.yml`.

+ `R/app_server.R`, `R/app_ui.R`: Top level UI and server elements. 

+ `R/run_app.R`: a function to configure and launch the application.

+ `dev/`: Scripts that will be used along the process of developing your app. You don't need to fill all the script before starting: use them as a notebook for keeping track of what you're doing all along the project life.

+ `inst/app/www`: Where you will add external dependencies in `www` (images, css, etc), notably added with the `golem` functions used to create external resources. 

+ `man`: Package documentation, to be generated by R & `{roxygen2}`.  

## `dev/01_start.R`

Once you've created your project, the first file that opens is `dev/01_start.R`. This file contains a series of commands that you'll have to run once, at the beginning of the project. 

Note that you don't have to fill everything, event thought it's strongly recommended.

### Fill the DESCRIPTION

First, fill the DESCRIPTION by adding information about the package that will contain your app. The first function, `fill_desc()`, can be used to fill your `DESCRIPTION` file.

```{r }
golem::fill_desc(
  pkg_name = "shinyexample", # The Name of the package containing the App 
  pkg_title = "PKG_TITLE", # The Title of the package containing the App 
  pkg_description = "PKG_DESC.", # The Description of the package containing the App 
  author_first_name = "AUTHOR_FIRST", # Your First Name
  author_last_name = "AUTHOR_LAST",  # Your Last Name
  author_email = "AUTHOR@MAIL.COM",      # Your Email
  repo_url = NULL # The (optional) URL of the GitHub Repo
)    
```

About [the DESCRIPTION file](https://r-pkgs.org/description.html).

### Add `{golem}` options

Please DO run this line of code, as it sets a series of global options inside `golem-config.yml` that will be reused inside `{golem}`.

```{r}
golem::set_golem_options()
```

### Set common Files 

If you want to use the MIT license, README, code of conduct, lifecycle badge, a news file, etc.

```{r eval = FALSE}
## See ?usethis for more information
usethis::use_mit_license( name = "Golem User" )  # You can set another license here
usethis::use_readme_rmd( open = FALSE )
usethis::use_code_of_conduct()
usethis::use_lifecycle_badge( "Experimental" )
usethis::use_news_md( open = FALSE )
```

See [`{usethis}`](https://usethis.r-lib.org/) for more info about these functions.

### Init Tests

Create a template for tests:

```{r}
golem::use_recommended_tests()
```

About [tests in a package](https://r-pkgs.org/tests.html).

### Use Recommended Packages

This will add "shiny", "DT", "attempt", "glue", "htmltools", and "golem" as a dependency to your package.

```{r}
golem::use_recommended_deps()
```

### Add various tools

+ If you want to change the default favicon

```{r}
# Remove current favicon
golem::remove_favicon()
# Add a new one
golem::use_favicon( path = "path/to/favicon")
```

Note that you can add an url, and the favicon will be downloaded to the `inst/app/www` folder. 

> **Note**: If you are deploying your app with [ShinyProxy](https://www.shinyproxy.io/), your favicon should have the `.png` extension, otherwise it is not going to work.

+ Utils

These two functions add a file with various functions that can be used along the process of building your app.

See each file in details for a description of the functions.

```{r}
golem::use_utils_ui()
golem::use_utils_server()
```

## Try the app

To run the app, go to the `dev/run_dev.R` file, and launch the all thing.

You're now set! You've successfully initiated the project and can go to dev/02_dev.R.

```{r}
rstudioapi::navigateToFile("dev/02_dev.R")
```

```{r eval = TRUE}
try(fs::dir_delete(x), silent = TRUE)
```

