Quick Started for Command Line Tool

This quick started guide assumes the setup page is read and the environment is prepared.
The complete source code is in github.

User Story

For a software development, defining the user story is the first thing. Our quick started user story is this.

My current mapping software needs to work with ShapeFile. But I need to explore what the ShapeFile looks like, such as what shape type it is, how many features it includes and what the fields it has. In my development, I often switch my laptop between home (Windows) and office (macOS), so I want a cross platform light weighted tool to help me out those kind of requirements.

Let’s Get Started

Open your terminal and follow the commands below:

1
2
3
4
5

mkdir quick-started-cmd
cd quick-started-cmd
yarn init -y
yarn add ginkgoch-map
touch main.js

At this step, we already setup a basic command line tool project layout. To make it simple, I will avoid to involve the ES6 or TypeScript, but it is actually compatible with those two. I will introduce the ES6 or TypeScript integration later.

Source Code:

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29

const fs = require('fs');
const G = require('ginkgoch-map').default.all;

function main() {
    // make sure shapefile is specified
    if (process.argv.length < 3) {
        console.info('Specified a shapefile path parameter');
        return;
    }

    // make sure the shapefile does exist
    let filePath = process.argv[2];
    if (!fs.existsSync(filePath)) {
        console.error(`File ${filePath} doesn't exist`);
        return;
    }

    // create a shapefile instance
    let source = new G.Shapefile(filePath);
    source.open();
    
    // get shapefile header and print it
    let header = source.header();
    for(let key of Object.keys(header)) {
        console.log(`${key}\t\t${header[key]}`);
    }
}

main();

Then execute command node main.js [a shapefile path] will print the header information.

1
2
3
4
5
6
7
8

fileCode: 9994
fileLength: 3813840
version: 1000
fileType: 5
minx: -20037508.23146975
miny: -20037508.231469806
maxx: 20037508.23146975
maxy: 18418382.328923147

Get to know more about our API to you can do more powerful functions.

Here is a complete command tool for shapefile node-shapefile-cli for your continue reading.