ascii-grid - npm Package Compare versions

Comparing version 0.1.2 to 0.2.0

package.json

 {
   "name": "ascii-grid",
-  "version": "0.1.2",
+  "version": "0.2.0",
   "description": "Identify and Read an ARC/INFO ASCII Grid",
   "main": "src",
   "scripts": {
-    "format": "npx prettier --write test.js src/*.js",
-    "test": "npx ava"
+    "format": "prettier --arrow-parens=avoid --trailing-comma=none --write test.js src/*.js",
+    "test": "ava --timeout=2m --verbose"
   },
@@ -32,4 +32,12 @@ "repository": {
   "devDependencies": {
-    "toab": "^1.0.1"
+    "ava": "^3.14.0",
+    "fast-max": "0.0.0",
+    "fast-min": "0.0.0",
+    "prettier": "^2.2.1",
+    "toab": "^1.0.2"
+  },
+  "dependencies": {
+    "get-byte": "0.0.0",
+    "to-typed-array": "0.0.1"
   }
 }

README.md

@@ -1,4 +0,2 @@
-:warning: Work in Progress.  This library is under active development and is not ready for production yet.
-
-# ascii-grid
+# ascii-grid: beta
 Identify and Read an ARC/INFO ASCII Grid
@@ -8,2 +6,3 @@
 ## identify ascii grid files
+isAsciiGrid identifies ASCII GRID files in the following formats: ArrayBuffer, Buffer, DataView, Promise, String, and Uint8Array
 ```javascript
@@ -30,3 +29,5 @@ const isAsciiGrid = require("ascii-grid/is-ascii-grid");
   cellsize: 0.0008333333333,
-  nodata_value: -9999
+  nodata_value: -9999,
+  last_metadata_line: 5,
+  last_metadata_byte: 95
 }
@@ -37,2 +38,7 @@ */
 ## Reading Pixel Values
-Coming Soon!
+```javascript
+const parseAsciiGridData = require("ascii-grid/parse-ascii-grid-data");
+
+const result = await parseAsciiGridData({ data: buffer, debug: true });
+// result is a two-dimensional array of rows with pixel values
+```

src/is-ascii-grid.js

@@ -1,9 +0,10 @@
-module.exports = (input, options = {}) => {
-  const debug = options.debug || false;
-  const max_read_length = options.max_read_length || 500;
+const getByte = require("get-byte");
 
-  if (typeof Buffer !== "undefined" && Buffer.isBuffer(input)) {
-    if (input.toString) {
-      input = input.toString("utf8", 0, max_read_length);
-      if (debug) console.log("converted input to a string");
+module.exports = async ({ data, debug = false, max_read_length = 500 }) => {
+  if (data instanceof Promise) data = await data;
+
+  if (typeof Buffer !== "undefined" && Buffer.isBuffer(data)) {
+    if (data.toString) {
+      data = data.toString("utf8", 0, max_read_length);
+      if (debug) console.log("converted data to a string");
     } else {
@@ -14,28 +15,28 @@ return false;
 
-  if (debug) console.log("input is:", input);
+  if (debug) console.log("[ascii-grid/is-ascii-grid] data is:", data);
 
-  if (input instanceof ArrayBuffer) input = new DataView(input);
+  if (data instanceof ArrayBuffer) data = new DataView(data);
 
-  if (input instanceof DataView) {
+  if (data instanceof DataView) {
     let decoded = "";
-    const length = Math.min(max_read_length, input.byteLength);
+    const length = Math.min(max_read_length, data.byteLength);
     for (let i = 0; i < length; i++) {
-      decoded += String.fromCharCode(input.getUint8(i));
+      decoded += String.fromCharCode(data.getUint8(i));
     }
-    input = decoded;
+    data = decoded;
   }
 
-  if (input instanceof Uint8Array) {
+  if (data instanceof Uint8Array) {
     let decoded = "";
-    for (let i = 0; i < Math.min(max_read_length, input.length); i++) {
-      decoded += String.fromCharCode(input[i]);
+    for (let i = 0; i < Math.min(max_read_length, data.length); i++) {
+      decoded += String.fromCharCode(data[i]);
     }
-    input = decoded;
+    data = decoded;
   }
 
-  if (typeof input === "string") {
-    if (debug) console.log("input is a string");
+  if (typeof data === "string") {
+    if (debug) console.log("data is a string");
     return (
-      Boolean(input.match(/.asc(.gz|.tar|.tar.gz|.tgz|.zip)?$/i)) ||
-      (input.includes("ncols") && input.includes("nrows"))
+      Boolean(data.match(/.asc(.gz|.tar|.tar.gz|.tgz|.zip)?$/i)) ||
+      (data.includes("ncols") && data.includes("nrows"))
     );
@@ -42,0 +43,0 @@ } else {

src/parse-ascii-grid-meta.js

@@ -1,43 +0,40 @@
-const NEWLINE_CHARCODE = "\n".charCodeAt(0);
+const getByte = require("get-byte");
 
-module.exports = (input, options = {}) => {
-  const debug = options.debug || false;
-  const max_read_length = options.max_read_length || 500;
-
+module.exports = async ({ data, debug = false, max_read_length = 500 }) => {
   const result = {};
-  if (typeof Buffer !== "undefined" && Buffer.isBuffer(input)) {
-    let i = 0;
 
-    // parse metadata
-    let line = null;
+  let i = 0;
 
-    const read_length = Math.min(input.length, max_read_length);
-    for (i = 0; i < read_length; i++) {
-      const char = String.fromCharCode(input[i]);
-      if (char === "\n") {
-        const [param, value] = line.split(" ");
-        result[param] = Number.parseFloat(value);
-        line = null;
-      } else if (line === null) {
-        if (
-          ["-", "0", "1", "2", "3", "4", "5", "6", "7", "8", "9"].includes(char)
-        ) {
-          break;
-        } else {
-          line = char;
-        }
+  let line_count = 0;
+  // parse metadata
+  let line = null;
+
+  const read_length = Math.min(data.length, max_read_length);
+  for (i = 0; i < read_length; i++) {
+    const byte = getByte(data, i);
+    const char = String.fromCharCode(byte);
+    if (char === "\n") {
+      const [param, value] = line.split(" ");
+      result[param] = Number.parseFloat(value);
+      line = null;
+      line_count++;
+    } else if (line === null) {
+      if (
+        ["-", "0", "1", "2", "3", "4", "5", "6", "7", "8", "9"].includes(char)
+      ) {
+        break;
       } else {
-        line += char;
+        line = char;
       }
+    } else {
+      line += char;
     }
   }
 
-  if (input instanceof ArrayBuffer) input = new DataView(input);
+  // add line that marks where metadata ends
+  result.last_metadata_line = line_count - 1;
+  result.last_metadata_byte = i - 1;
 
-  if (input instanceof DataView) {
-    const decoded = "";
-    input = decoded;
-  }
   if (debug) console.log("result:", result);
   return result;
 };

test.js

 const { readFileSync } = require("fs");
 const test = require("ava");
 const toab = require("toab");
+const fastMin = require("fast-min");
+const fastMax = require("fast-max");
 
 const isAsciiGrid = require("./src/is-ascii-grid");
 const parseAsciiGridMetaData = require("./src/parse-ascii-grid-meta");
+const parseAsciiGridData = require("./src/parse-ascii-grid-data");
 
-test("identifying ascii grid file extensions", async (t) => {
-  t.true(isAsciiGrid("michigan_lld.asc"));
-  t.true(isAsciiGrid("michigan_lld.asc.tar"));
-  t.true(isAsciiGrid("michigan_lld.asc.tar.gz"));
-  t.true(isAsciiGrid("michigan_lld.asc.zip"));
-  t.false(isAsciiGrid("michigan_lld.asc.json"));
+test("identifying ascii grid file extensions", async t => {
+  t.true(await isAsciiGrid({ data: "michigan_lld.asc" }));
+  t.true(await isAsciiGrid({ data: "michigan_lld.asc.tar" }));
+  t.true(await isAsciiGrid({ data: "michigan_lld.asc.tar.gz" }));
+  t.true(await isAsciiGrid({ data: "michigan_lld.asc.zip" }));
+  t.false(await isAsciiGrid({ data: "michigan_lld.asc.json" }));
 });
 
-test("identifying ascii grid file from buffers", async (t) => {
+test("identifying ascii grid file from buffers", async t => {
   const buffer = readFileSync("./test_data/michigan_lld/michigan_lld.asc");
-  const bufferIsAsciiGrid = isAsciiGrid(buffer, { debug: false });
+  const bufferIsAsciiGrid = await isAsciiGrid({ data: buffer, debug: false });
   t.true(bufferIsAsciiGrid);
-  t.true(isAsciiGrid(Uint8Array.from(buffer)));
-  t.true(isAsciiGrid(toab(buffer)));
+  t.true(await isAsciiGrid({ data: Uint8Array.from(buffer) }));
+  t.true(await isAsciiGrid({ data: await toab(buffer) }));
 });
 
-test("reading ascii metadata", async (t) => {
+test("reading ascii metadata", async t => {
   const buffer = readFileSync("./test_data/michigan_lld/michigan_lld.asc");
-  const meta = parseAsciiGridMetaData(buffer, { debug: false });
+  const meta = await parseAsciiGridMetaData({ data: buffer, debug: false });
 
@@ -35,2 +38,17 @@ // check metadata
   t.is(meta.nodata_value, -9999);
+  t.is(meta.last_metadata_line, 5);
+  t.is(meta.last_metadata_byte, 95);
 });
+
+test("reading ascii values", async t => {
+  const buffer = readFileSync("./test_data/michigan_lld/michigan_lld.asc");
+  const result = await parseAsciiGridData({ data: buffer, debug: true });
+
+  const lastRow = result.values[result.values.length - 1];
+  t.is(fastMin(lastRow, { debug: false }), -0.102997);
+  t.is(fastMax(lastRow, { debug: false }), 165.940948);
+  t.is(result.values.length, 5365);
+  t.deepEqual(Array.from(new Set(result.values[0])).sort(), [-9999, 9999]);
+  t.true(result.values.every(ln => ln.length === 4201));
+  t.deepEqual(new Set(result.values[result.values.length - 1]).size, 3615);
+});

New alerts

Major refactor

Supply chain risk

Package has recently undergone a major refactor. It may be unstable or indicate significant internal changes. Use caution when updating to versions that include significant changes.

Found 1 instance in 1 package

Improved metrics

Total package byte prevSize

15673

increased by17.53%

Lines of code

178

increased by26.24%

Number of lines in readme file

41

increased by13.89%

Worsened metrics

Dependency count

2

increased byInfinity%

Dev dependency count

5

increased by400%

Number of medium supply chain risk alerts

1

increased byInfinity%

Dependency changes

• + Addedget-byte@0.0.0

• + Addedto-typed-array@0.0.1

• + Added@extra-number/significant-digits@2.0.27(transitive)

• + Addedchoose-typed-array@0.0.1(transitive)

• + Addedget-byte@0.0.0(transitive)

• + Addedto-typed-array@0.0.1(transitive)