dplyr as a CLI. Never use awk again.

dplyr.R

#!/usr/bin/env Rscript
# (Don't forget: `chmod +x dplyr`)
# Copyright 2018 Eoin Travers <[email protected]>
#
#  This file is free software: you may copy, redistribute and/or modify it
#  under the terms of the GNU General Public License as published by the
#  Free Software Foundation, either version 2 of the License, or (at your
#  option) any later version.
#
#  This file is distributed in the hope that it will be useful, but
#  WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
#  General Public License for more details.
#
#  You should have received a copy of the GNU General Public License
#  along with this program.  If not, see <http://www.gnu.org/licenses/>.
suppressMessages(library(optparse))
suppressMessages(library(dplyr))
option_list <- list(
    make_option(c("-p", "--pretty"), action="store_true", default=FALSE,
                help="Print result tibble, rather than raw csv. [default FALSE]")
)
parser <- OptionParser(
    usage = "dplyr [options] data.csv 'data %>% command1() %>% command2()'",
    option_list=option_list)
arguments <- parse_args(parser, positional_arguments = 2)
args  <- arguments$args
stopifnot(length(args)==2)
inp <- args[[1]]
cmd <- args[[2]]

data  <- read.csv(inp) %>% as.tbl
result  <- parse(text=cmd) %>% eval()
if(arguments$options$pretty){
    print(result)
} else {
    txt  <- textConnection('csv_result', 'w')
    write.csv(result, txt, quote=F, row.names=F)
    paste(csv_result, collapse='\n') %>% paste0('\n') %>% cat()
}