Write data to a flat file with type schema preservation

Writes a data frame to a flat file format (CSV by default) and stores the column type schema in a companion parquet file. This enables type-preserving round-trips for formats that don't natively preserve types, while keeping data in human-readable flat files suitable for GitHub collaboration.

Usage

ngr_fs_type_write(
  x,
  path,
  format = "csv",
  schema_suffix = "schema",
  schema_only = FALSE
)

Arguments

x

A data.frame or tibble::tibble to write.

path

Character. Path to write the file to.

format

Character. File extension to replace when creating the schema file. Default is "csv".

schema_suffix

Character. Suffix to append to base filename for the schema file. Default is "schema" (e.g., data.csv -> data_schema.parquet). Use "" for no suffix (e.g., data.csv -> data.parquet).

schema_only

Logical. If TRUE, only write the schema parquet file, not the data file. Default is FALSE.

Value

Invisibly returns the file path.

See also

ngr_fs_type_read() for reading files with preserved types

Other fs: ngr_fs_copy_if_missing(), ngr_fs_id_missing(), ngr_fs_type_read()

Other serialization: ngr_fs_type_read()

Examples

if (FALSE) { # \dontrun{
# Create example data with various types
df <- data.frame(
  int_col = 1:3L,
  dbl_col = c(1.1, 2.2, 3.3),
  chr_col = c("a", "b", "c"),
  date_col = as.Date(c("2024-01-01", "2024-01-02", "2024-01-03")),
  lgl_col = c(TRUE, FALSE, TRUE)
)

# Write to temporary file
path <- tempfile(fileext = ".csv")
ngr_fs_type_write(df, path)

# Schema file is created alongside
schema_path <- sub("\\.csv$", "_schema.parquet", path)
file.exists(schema_path)

# Read back with types preserved
df2 <- ngr_fs_type_read(path)
str(df2)
} # }