xcsrz

Code Snippets

Posting from Dart to a URL with a redirect: Since Dart's stock http package (and even the dio package) chose to handle redirects differently than basically every other language+package out there and disregard redirect responses returned to a POST request you have to do a little extra work. Worse than anything is every solution I have found was #doingItWrong and making the followup request a POST request complete with sending the payload each time. Even those approaches fail to successfully POST to a google app script (GAS). All of this is quite ironic since Dart is itself a product of Google. This is a simple proof of concept and only supports one redirect which all that is needed for a GAS doPost endpoint, but could be modified easily to accomodate other situations.

	import 'dart:convert';
	import 'dart:io';

	import 'package:http/http.dart';

	String url =
	"https://script.google.com/macros/s/YOUR_DEPLOYMENT_HASH_HERE/exec";

	final data = {
	'foo': 456,
	'bar': 'that',
	'biz': 23,
	};

	void main(List<String> args) {
	postRequestWithRedirect(url, jsonEncode(data)).then((r) {
	print('code: ' + r.statusCode.toString());
	print('body: ' + r.responseBody.toString());
	});
	}

	class postRequestWithRedirectResult {
	num? statusCode;
	String? responseBody;
	}


	Future<postRequestWithRedirectResult> postRequestWithRedirect(
	String url,
	String body,
	) async {
	var httpclient = HttpClient();
	HttpClientRequest request;
	HttpClientResponse response;
	postRequestWithRedirectResult result = postRequestWithRedirectResult();
	try {
	request = await httpclient.postUrl(Uri.parse(url));
	request.headers.contentLength = body.length;
	request.write(body);
	response = await request.close();
	final location = response.headers.value(HttpHeaders.locationHeader);
	if (response.statusCode == 302 && location != null) {
	request = await httpclient.getUrl(Uri.parse(location));
	response = await request.close();
	result.statusCode = response.statusCode;
	result.responseBody = await response.transform(utf8.decoder).join();
	} else {
	result.statusCode = response.statusCode;
	result.responseBody = await response.transform(utf8.decoder).join();
	}
	} finally {
	httpclient.close(force: true);
	return result;
	}
	}

view raw post_request_with_redirect_result.dart hosted with ❤ by GitHub

Add a gentle fade-in from black to the beginning and a matching fade-out to the end of a video clip

	#!/bin/bash


	destfile() {
	dir=$(dirname "$1")
	filename=$(basename -- "$1");
	extension="${filename##*.}";
	basename="${filename%.*}";
	filepath="${dir}/${basename}-faded.${extension}";
	c=0
	while [ -f "$filepath" ]; do
	c=$((c+1))
	filepath="${dir}/${basename}-faded-${c}.${extension}";
	done
	echo "${filepath}";
	}


	SRCFILE=$1
	FADEIN=${2:-'1.5'}
	FADEOUT=${3:-$FADEIN}

	if [ "${SRCFILE}" == "" ]; then
	echo "You must provide a source file";
	exit;
	fi

	if [ ! -f "${SRCFILE}" ]; then
	echo "${SRCFILE} does not exists.";
	exit;
	fi

	echo "reading from ${SRCFILE}";
	OUTFILE=$(destfile "${SRCFILE}");
	echo "writing to ${OUTFILE}"

	LENGTH=$(ffprobe -v error -show_entries format=duration -of default=noprint_wrappers=1:nokey=1 "${SRCFILE}")
	STARTFADEOUT=$(echo "${LENGTH} ${FADEOUT}" \| awk '{ print $1-$2 }')

	ffmpeg -i "${SRCFILE}" -vf "fade=t=in:st=0:d=${FADEIN},fade=t=out:st=${STARTFADEOUT}:d=${FADEOUT}" "${OUTFILE}"

	echo "done writing ${OUTFILE}."

view raw add-fades-to-video.sh hosted with ❤ by GitHub

Install Python 3.9 on CentOS or Amazon Linux

	#!/bin/sh

	sudo yum install gcc openssl-devel bzip2-devel libffi-devel zlib-devel
	cd /tmp
	wget https://www.python.org/ftp/python/3.9.6/Python-3.9.6.tgz
	tar -xvf Python-3.9.6.tgz
	cd Python-3.9.6
	./configure --enable-optimizations
	sudo make altinstall
	python3.9 --version

view raw install-python-3.9-on-centos.sh hosted with ❤ by GitHub

Reconcile descrepencies in document counts within elasticsearch

	from requests import get
	from json import dumps, loads
	from prettytable import PrettyTable


	src_server = 'http://localhost:9200'

	def docCount(idx=None, typ=None):
	url = src_server
	if idx:
	url += "/%s" % idx
	if typ:
	url += "/%s" % typ
	url += "/_count"
	res = loads(get(url).content)
	return res['count'] if 'count' in res else 0



	tbl = PrettyTable(['Index', 'Count on Index', 'Docs In Types'])
	tbl.add_row(['entire cluster', docCount(), 'n/a'])
	tbl.add_row(['=====','=====','====='])
	src_state=loads(get("%s/_cluster/state" % (src_server), timeout=600).content)
	docsCountedInIndexes = 0
	docsCountedInTypes = 0
	for idx in src_state['metadata']['indices']:
	docsInIndex = docCount(idx)
	docsCountedInIndexes += docsInIndex
	docsInTypes = 0
	for typ in src_state['metadata']['indices'][idx]['mappings']:
	docsInTypes += docCount(idx, typ)
	docsCountedInTypes += docsInTypes
	tbl.add_row([idx, docsInIndex, docsInTypes])

	tbl.add_row(['-----','------','-----'])
	tbl.add_row(['Totals', docsCountedInIndexes, docsCountedInTypes])

	print(tbl)

view raw es-doc-accounting.py hosted with ❤ by GitHub

This script prints out the current list of Amazon2 Linux AMI's by region (kernel 5.10, HVM, x86_64, gp2). Changing the image variable and the Path filter make this capable of searching for any public/shared image.

	import boto3
	from json import dumps
	from yaml import dump

	image = 'amzn2-ami-kernel-5.10-hvm-x86_64-gp2'

	regions = [
	'ap-northeast-1',
	'ap-northeast-2',
	'ap-northeast-3',
	'ap-south-1',
	'ap-southeast-1',
	'ap-southeast-2',
	'ca-central-1',
	'eu-central-1',
	'eu-north-1',
	'eu-west-1',
	'eu-west-2',
	'eu-west-3',
	'sa-east-1',
	'us-east-1',
	'us-east-2',
	'us-west-1',
	'us-west-2',
	]

	amis = {}
	for region in regions:
	client = boto3.client('ssm', region)

	paginator = client.get_paginator('get_parameters_by_path')
	iterator = paginator.paginate(
	Path='/aws/service/ami-amazon-linux-latest'
	)
	matches = []
	for batch in iterator:
	matches.extend(list(filter(lambda det: image in det['Name'], batch['Parameters'])))

	if len(matches) < 1:
	print('no matches found in', region)
	continue
	elif len(matches) > 1:
	print('multiple matches found in', region, '- perhaps you should narrow your results')
	for match in matches:
	print("\t-", match)

	# grab the first one if we have more than one
	print('found', matches[0]['Name'], matches[0]['Value'], 'in', region)
	amis[region] = {'AMI': matches[0]['Value']}

	print(dumps(amis, indent=4))
	print(dump(amis))

view raw amazon2-linux-amis-for-cloudformation.py hosted with ❤ by GitHub