Add -m renaming files to MXF date/time

Use getopts native unknown method.
Add -v for logging of files as they are written.

Author: jimt

README.md

@@ -5,12 +5,18 @@ webcam still images and save them to the current directory.
 
 ## Use
 
-`node {-t nnn} URL`
+```
+node [options] URL
 
-where `nnn` is the fetch interval (default 5000).
+  -i nnn, --interval nnn    mS between fetches [default: 5000]
+  -m, --mxf                 rename files to MXF creation time
+  -v, --verbose             show filenames as they are written
+  -h, --help                show this help
+```
 
 If URL ends in a `=` an incrementing integer is appended
 to it for each fetch in an attempt to avoid aggressive
 request caching.
 
-Files are named for the number of mS past the epoch when the fetch started.
+By default, files are named for the number of mS past the
+epoch when the fetch started.

package-lock.json

@@ -1,6 +1,6 @@
 {
   "name": "webstills",
-  "version": "1.0.0",
+  "version": "1.1.0",
   "description": "fetch webcam still images to local disk",
   "main": "index.js",
   "scripts": {
@@ -22,10 +22,10 @@
   },
   "eslintConfig": {
     "env": {
-        "browser": false,
-        "commonjs": true,
-        "es6": true,
-        "node": true
+      "browser": false,
+      "commonjs": true,
+      "es6": true,
+      "node": true
     },
     "extends": "eslint:recommended",
     "parser": "typescript-eslint-parser",
@@ -36,7 +36,11 @@
       }
     },
     "rules": {
-        "no-console": "off"
+      "no-console": "off"
     }
+  },
+  "repository": {
+    "type": "git",
+    "url": "git+https://github.com/jimt/webstills"
   }
 }

package.json

@@ -6,25 +6,37 @@ const DEFAULT_MS = 5000; // time between fetches
 const fs = require("fs");
 const got = require("got");
 const getopts = require("getopts");
+
 var count = 0;
 var start = 0;
 var dup = 0;
 var filename;
 var lastImage;
 
-const options = getopts(process.argv.slice(2), {
-  boolean: ["h"],
-  string: ["t"],
+var invalidOption = false;
+const OPTIONSDOC = {
+  boolean: ["m", "v", "h"],
+  string: ["i"],
   alias: {
-    interval: ["t"],
+    mxf: ["m"],
+    interval: ["i"],
+    verbose: ["v"],
     help: ["h"]
+  },
+  unknown: option => {
+    invalidOption = true;
+    console.error(`Unknown option: ${option}`);
+    return false;
   }
-});
+};
+const options = getopts(process.argv.slice(2), OPTIONSDOC);
 
 function usage() {
   console.log(`
 Usage: webstills [options] URL
-  -t nnn, --interval nnn    mS between fetches [default: 5000]
+  -i nnn, --interval nnn    mS between fetches [default: 5000]
+  -m, --mxf                 rename files to MXF creation time
+  -v, --verbose             show filenames as they are written
   -h, --help                show this help
 N.B.  If URL ends with =, an incrementing counter is added to
       the URL to improve cache busting.
@@ -36,23 +48,53 @@ N.B.  If URL ends with =, an incrementing counter is added to
   }
 }
 
+function mxfdtname(d) {
+  let daterxarr = /DAT=(\d{4}-\d\d-\d\d)[\r\n]/.exec(d);
+  let timerxarr = /TIM=(\d\d:\d\d:\d\d\.\d{3})[\r\n]/.exec(d);
+  if (daterxarr && timerxarr) {
+    return `${daterxarr[1].replace(/-/g, "")}-${timerxarr[1].replace(
+      /:/g,
+      ""
+    )}.jpg`;
+  }
+  return null;
+}
+
 function writeImage(filename, data) {
-  fs.writeFile(filename + ".jpg", data, err => {
-    if (err) console.log(`${count}: error writing: ${filename}.jpg`);
+  let newname;
+  filename = `${filename}.jpg`;
+  fs.writeFile(filename, data, err => {
+    if (err) {
+      console.error(`${count}: error writing: ${filename}.jpg`);
+    } else {
+      if (options.m) {
+        newname = mxfdtname(data.toString("binary", 0, 2047));
+        if (newname) {
+          fs.rename(filename, newname, err => {
+            if (err) {
+              console.error(`error renaming ${filename} to ${newname}`);
+            }
+          });
+        }
+      }
+    }
+    if (options.v) {
+      console.log(newname ? newname : filename);
+    }
   });
 }
 
 function writeDup(filename, data) {
   let dupstr = ("0000" + dup).slice(-5);
-  console.log(`Write ${filename}.${dupstr}`);
+  console.log(`Write duplicate ${filename}.${dupstr}`);
   writeImage(`${filename}.${dupstr}`, data);
   dup++;
 }
 
 async function fetcher() {
   let gotOptions = {
     retries: 0,
-    timeout: Math.min(1000, options.t),
+    timeout: Math.min(1200, options.i),
     encoding: null,
     headers: {
       "user-agent":
@@ -91,10 +133,11 @@ async function fetcher() {
 
 if (
   options._.length !== 1 ||
-  (options.t.length && isNaN(parseInt(options.t, 10)))
+  invalidOption ||
+  (options.i.length && isNaN(parseInt(options.i, 10)))
 ) {
   usage();
 } else {
-  options.t = parseInt(options.t, 10) || DEFAULT_MS;
-  setInterval(fetcher, options.t);
+  options.i = parseInt(options.i, 10) || DEFAULT_MS;
+  setInterval(fetcher, options.i);
 }