script to set id

1 files changed, 68 insertions, 0 deletions

diff --git a/bin/id.js b/bin/id.js
new file mode 100755
index 0000000..de60e99
--- /dev/null
+++ b/bin/id.js
@@ -0,0 +1,68 @@
+#!/usr/bin/env node
+
+/**
+ * Set GeoJSON id
+ */
+
+const fs = require('fs')
+const { Transform, pipeline } = require('stream')
+const ndjson = require('ndjson')
+
+const argv = require('yargs/yargs')(process.argv.slice(2))
+  .option('property', {
+    type: 'boolean',
+    description: 'Also set id as a property'
+  })
+  .argv
+
+if (argv._.length < 2) {
+  console.error("Usage: ./id.js input.geojson output.geojson")
+  process.exit(1)
+}
+
+const inputFile = argv._[0]
+const outputFile = argv._[1]
+
+if (!fs.existsSync(inputFile)) {
+  console.error(`${inputFile} not found`)
+  process.exit(1)
+}
+
+let index = 0
+const id = new Transform({
+  readableObjectMode: true,
+  writableObjectMode: true,
+  transform(feature, encoding, callback) {
+    index++
+
+    if (process.stdout.isTTY && index % 10000 === 0) {
+      process.stdout.write(` ${index.toLocaleString()}\r`)
+    }
+
+    feature.id = index
+
+    if (argv.property) {
+      feature.properties.id = index
+    }
+
+    this.push(feature)
+
+    callback()
+  }
+})
+
+pipeline(
+  fs.createReadStream(inputFile),
+  ndjson.parse(),
+  id,
+  ndjson.stringify(),
+  fs.createWriteStream(outputFile),
+  err => {
+    if (err) {
+      console.log(err)
+      process.exit(1)
+    } else {
+      process.exit(0)
+    }
+  }
+)