add recursive search to load_dot_env

[jbowers85]

Added functionality to recursively search parent directories for an .env file. Users can opt-in to this by setting recursive = TRUE. If recursive = TRUE, then load_dot_env will search the directory, and if no .env file is found, parent directories are searched until one is found.

[gaborcsardi]

Is it possibly to get into an infinite loop here with symbolic links? Should we have some limit (100?) for the number of directories to try?

[jbowers85]

Good idea, we can account for symbolic links by keeping track of the visited directories. Here is some updated logic. What are your thoughts?

load_dot_env <- function(file = ".env", recursive = FALSE) {
  # Normalize the initial file path for consistent path handling
  original_path <- normalizePath(file, mustWork = FALSE)
  
  # Initialize the visited directories tracker and the found file path
  visited <- character(0)
  found_file <- character(0)
  
  if (!file.exists(original_path)) {
    if (recursive) {
      # Start with the directory containing the original path
      path <- dirname(original_path)
      
      # Loop until we find the file or reach the root directory
      while (!identical(path, normalizePath(dirname(path)))) {
        # Normalize the current directory path for accurate detection
        normalized_path <- normalizePath(path, mustWork = FALSE)
        
        # Break the loop if a cycle is detected
        if (normalized_path %in% visited) break
        
        # Track the visited directory to prevent cycles
        visited <- c(visited, normalized_path)
        
        # Construct the expected .env file path for the current directory
        test_path <- file.path(normalized_path, basename(original_path))
        
        # If the .env file is found, update `found_file` and exit the loop
        if (file.exists(test_path)) {
          found_file <- test_path
          break
        }
        
        # Move up one directory level
        path <- dirname(normalized_path)
      }
      
      # If no file was found in the entire search, raise an error
      if (length(found_file) == 0) {
        stop(sprintf("No .env file found from '%s' up to the root directory", original_path), call. = TRUE)
      } else {
        file <- found_file
      }
    } else {
      # Raise an error if recursive is FALSE and the .env file does not exist in the specified location
      stop(sprintf(".env file does not exist in the specified path: '%s'", original_path), call. = TRUE)
    }
  }
  
  # Read and process the .env file
  tmp <- readLines(file)
  tmp <- ignore_comments(tmp)
  tmp <- ignore_empty_lines(tmp)
  
  # If no environment variables are found, return invisibly
  if (length(tmp) == 0) return(invisible())
  
  # Parse and set environment variables from the .env file
  tmp <- lapply(tmp, parse_dot_line)
  set_env(tmp)
}

[gaborcsardi]

Yeah, that looks good to me.

[jbowers85]

Friendly ping @gaborcsardi

[cswingle]

Add my +1 to this merge

[skr5k]

+1