A simple CLI to demonstrate a few concepts:
- Reading a file line by line for better memory footprint at the cost of slower performance
- Cryptographic hashes for randomised and uniquely specific checksums
- async/await fs.readFileSync as alternative to fs.readFile's callback
- CLI wrapper for Node
Requires
- Node LTS
yarn
Run yarn at root folder
Use -h to see codified information. Below are some examples:
./index.js -h
Usage: index <input> PLACE*4,4,NORTH_MOVE_LEFT_RIGHT_REPORT
CLI to process multiple instructions in batches, with the ability to resume
Options:
-V, --version output the version number
-f, --file <path> Input file of multi-line commands such as:
PLACE 0,0,NORTH
MOVE
LEFT
RIGHT
REPORT
-d, --debug Debug flag to print out helpful messages during runtime.
-s, --store Create a checksum of input file and store config there to continue next time. Implied by default. Use -r to override.
--reset Ignore stored config and start anew.
-h, --help output usage information
./index.js -f tests/1.txt -d
Input file, tests/1.txt
File checksum da39a3ee5e6b4b0d3255bfef95601890afd80709
Processing line by line...
Previous config { x: 0, y: 0, direction: 'NORTH', linesToSkip: 0 }
Saving current config { x: 0, y: 0, direction: 'NORTH', linesToSkip: 0 } to /tmp/toy-robot-da39a3ee5e6b4b0d3255bfef95601890afd80709
./index.js -f tests/3.txt --reset -d
Input file, tests/3.txt
File checksum b6895a8822defbfad7180ab18cd667ab5db02b52
Processing line by line...
Previous config {}
PLACE 6,6,WEST Unable to place. Co-ordinates (6, 6) are invalid. Direction WEST is valid.
PLACE 5,5,WEST1 Unable to place. Co-ordinates (5, 5) are valid. Direction WEST1 is invalid.
PLACE 4,4,NORTH Placed. Currently at 4, 4, NORTH.
MOVE Successful. Currently at 4, 5, NORTH.
LEFT Rotated from NORTH to WEST.
MOVE Successful. Currently at 5, 5, WEST.
MOVE Unable to move, would go out of bounds. Currently at 5, 5, WEST.
MOVE Unable to move, would go out of bounds. Currently at 5, 5, WEST.
REPORT 5 5 WEST
REPORT 5 5 WEST
Saving current config { x: 5, y: 5, direction: 'WEST', linesToSkip: 10 } to /tmp/toy-robot-b6895a8822defbfad7180ab18cd667ab5db02b52
./index.js -f tests/3.txt -d
Input file, tests/3.txt
File checksum b6895a8822defbfad7180ab18cd667ab5db02b52
Processing line by line...
Previous config { x: 5, y: 5, direction: 'WEST', linesToSkip: 10 }
1 / 10 lines skipped.
2 / 10 lines skipped.
3 / 10 lines skipped.
4 / 10 lines skipped.
5 / 10 lines skipped.
6 / 10 lines skipped.
7 / 10 lines skipped.
8 / 10 lines skipped.
9 / 10 lines skipped.
10 / 10 lines skipped.
Saving current config { x: 5, y: 5, direction: 'WEST', linesToSkip: 10 } to /tmp/toy-robot-b6895a8822defbfad7180ab18cd667ab5db02b52