I have been plagued by this thing for a few weeks: every time I turn on the Wi-Fi, then turn it off, something starts turning the Bluetooth on. Turn it off and it goes back up in a minute. The only solution was to turn off the phone and then back again without turning Wi-fi or Bluetooth on. Strangely enough, there is no way to disable Bluetooth on the phone and no way to know who turned it on last.

As an investigation, I tried something called Event Logger, which logs when Bluetooth is turned on or off, but fails to notify you of what did it. In fact, I am still not sure how I was supposed to determine what software did it and this demonstrates a systemic issue with mobile phones: you have no real control or even knowledge over what happens in it.

Long story short, I've uninstalled a lot of applications just to see if the problem goes away. In the end it was Firechat! After uninstalling it, the problem went away. Apparently I am not the only one experiencing this, although one of the few pages on the Internet regarding Firechat and Bluetooth claims Firechat does not turn it on by itself, although numerous reviews on the app's Google Store page say differently.

Update 17 June 2016: I've changed the focus of the extension to simply change the aspect of stories based on status, so that stories with content are highlighted over simple shares. I am currently working on another extension that is more adaptive, but it will be branded differently.

Update 27 May 2016: I've published the very early draft of the extension because it already does a cool thing: putting original content in the foreground and shrinking the reposts and photo uploads and feeling sharing and all that. You may find and install the extension here.

Have you ever wanted to decrease the spam in your Facebook page but couldn't do it in any way that would not make you miss important posts? I mean, even if you categorize all your contacts into good friends, close friends, relatives, acquaintances, then you unfollow the ones that really spam too much and you hide all posts that you don't like, you have no control over how Facebook decides to order what you see on the page. Worse than that, try to refresh repeatedly your Facebook page and see wildly oscillating results: posts appear, disappear, reorder themselves. It's a mess.

Well, true to this and my word I have started work on a Chrome extension to help me with this. My plan is pretty complicated, so before I publish the extension on the Chrome Webstore, like I did with my previous two efforts, I will publish this on GitHub while I am still working on it. So, depending on where I am, this might be alpha, beta or stable. At the moment of this writing - first commit - alpha is a pretty big word.

Here is the plan for the extension:
  1. Detect the user has opened the Facebook page
  2. Inject jQuery and extension code into the page
  3. Detect any post as it appears on the page
  4. Extract as many features as possible
  5. Allow the user to create categories for posts
  6. Allow the user to drag posts into categories or out of them
  7. Use AI to determine the category a post most likely belongs to
  8. Alternatively, let the user create their own filters, a la Outlook
  9. Show a list of categories (as tabs, perhaps) and hide all posts under the respective categories
This way, one might skip the annoying posts, based on personal preferences, while still enjoying the interesting ones. At the time of this writing, the first draft, the extension only works on https://www.facebook.com, not on any subpages, it extracts the type of the post and sets a CSS class on it. It also injects a CSS which makes posts get dimmer and smaller based on category. Mouse over to get the normal size and opacity.

How to make it work for you:
  1. In Chrome, go to Manage Extensions (chrome://extensions/)
  2. Click on the Developer Mode checkbox
  3. Click on the Load unpacked extension... button
  4. Select a folder where you have downloaded the source of this extension
  5. Open a new tab and load Facebook there
  6. You should see the posts getting smaller and dimmer based on category.
Change statusProcessor.css to select your own preferences (you may hide posts altogether or change the background color, etc).

As usual, please let me know what you think and contribute with code and ideas.

I've written another Chrome extension that I consider in beta, but so far it works. Really ugly makeshift code, but I am not gathering data about the way I will use it, then I am going to refactor it, just as I did with Bookmark Explorer. You may find the code at GitHub and the extension at the Chrome webstore.

This is how it works: Every time you access anything with the browser, the extension will remember the IPs for any given host. It will hold a list of the IPs, in reverse order (last one first), that you can just copy and paste into your hosts file. The hosts file is found in c:/Windows/System32/drivers/etc/hosts and on Linux in /etc/hosts. Once you add a line in the format "IP host" in it, the computer will resolve the host with the provided IP. Every time there is a problem with DNS resolution, the extension will add the latest known IP into the hosts text. Since the extension doesn't have access to your hard drive, you need to edit the file yourself. The icon of DNS resolver will show the number of hosts that it wants to resolve locally or nothing, if everything is OK.

The extension allows manual selection of an IP for a host and forced inclusion or exclusion from the list of IP/host lines. Data can be erased (all at once for now) as well. The extension does not communicate with the outside, but it does store a list of all domains you visit, so it is a slight privacy risk - although if someone has access to the local store of a browser extension, it's already too late. There is also the possibility of the extension to replace the host with IP directly in the browser requests, but this only works for the browser and fails in case the host name is important, as in the case of multiple servers using the same IP, so I don't recommend using it.

There are two scenarios for which this extension is very useful:
  • The DNS server fails for some reason or gives you a wrong IP
  • Someone removed the IP address from DNS servers or replaced it with one of their own, like in the case of governments censorship

I have some ideas for the future:
  • Sharing of working IP/host pairs - have to think of privacy before that, though
  • Installing a local DNS server that can communicate locally with the extension, so no more hosts editing - have to research and create one
  • Upvoting/Downvoting/flagging shared pairs - with all the horrible head-ache this comes with

As usual, let me know what you think here, or open issues on GitHub.

Update 29 August 2017 - Version 3.0.4: The extension has been rewritten in EcmaScript6 and tested on Chrome, Firefox and Opera.

Update 03 March 2017 - Version 2.9.3: added a function to remove marketing URLs from all created bookmarks. Enable it in the Advanced settings section. Please let me know of any particular parameters you need purged. So far it removes utm_*, wkey, wemail, _hsenc, _hsmi and hsCtaTracking.

Update 26 February 2017: Version (2.9.1): added customizing the URL comparison function. People can choose what makes pages different in general or for specific URL patterns
Update 13 June 2016: Stable version (2.5.0): added Settings page, Read Later functionality, undelete bookmarks page and much more.
Update 8 May 2016: Rewritten the extension from scratch, with unit testing.
Update 28 March 2016: The entire source code of the extension is now open sourced at GitHub.

Whenever I read my news, I open a bookmark folder containing my favorite news sites, Twitter, Facebook, etc. I then proceed to open new tabs for each link I find interesting, closing the originating links when I am done. Usually I get a number of 30-60 open tabs. This wreaks havoc on my memory and computer responsiveness. And it's really stupid, because I only need to read them one by one. In the end I've decided to fight my laziness and create my first browser extension to help me out.

The extension is published here: Siderite's Bookmark Explorer and what it does is check if the current page is found in any bookmark folder, then allow you to go forward or backwards inside that folder.

So this is my scenario on using it:
  1. Open the sites that you want to get the links from.
  2. Open new tabs for the articles you want to read or YouTube videos you want to watch,etc.
  3. Bookmark all tabs into a folder.
  4. Close all the tabs.
  5. Navigate to the bookmark folder and open the first link.
  6. Read the link, then press the Bookmark Navigator button and then the right arrow. (now added support for context menu and keyboard shortcuts)
  7. If you went too far by mistake, press the left arrow to go back.

OK, let's talk about how I did it. In order to create your own Chrome browser extension you need to follow these steps:

1. Create the folder


Create a folder and put inside a file called manifest.json. It's possible structure is pretty complex, but let's start with what I used:
{
"manifest_version" : 2,

"name" : "Siderite's Bookmark Explorer",
"description" : "Gives you a nice Next button to go to the next bookmark in the folder",
"version" : "1.0.2",

"permissions" : [
"tabs",
"activeTab",
"bookmarks",
"contextMenus"
],
"browser_action" : {
"default_icon" : "icon.png",
"default_popup" : "popup.html"
},
"background" : {
"scripts" : ["background.js"],
"persistent" : false
},
"commands" : {
"prevBookmark" : {
"suggested_key" : {
"default" : "Ctrl+Shift+K"
},
"description" : "Navigate to previous bookmark in the folder"
},
"nextBookmark" : {
"suggested_key" : {
"default" : "Ctrl+Shift+L"
},
"description" : "Navigate to next bookmark in the folder"
}
}
}

The manifest version must be 2. You need a name, a description and a version number. Start with something small, like 0.0.1, as you will want to increase the value as you make changes. The other thing is that mandatory is the permissions object, which tells the browser what Chrome APIs you intend to use. I've set there activeTab, because I want to know what the active tab is and what is its URL, tabs, because I might want to get the tab by id and then I don't get info like URL if I didn't specify this permission, bookmarks, because I want to access the bookmarks, and contextMenus, because I want to add items in the page context menu. More on permissions here.

Now, we need to know what the extension should behave like.

If you want to click on it and get a popup that does stuff, you need to specify the browser_action object, where you specify the icon that you want to have in the Chrome extensions bar and/or the popup page that you want to open. If you don't specify this, you get a default button that does nothing on click and presents the standard context menu on right click. You may only specify the icon, though. More on browserAction here.

If you want to have an extension that reacts to background events, monitors URL changes on the current page, responds to commands, then you need a background page. Here I specify that the page is a javascript, but you can add HTML and CSS and other stuff as well. More on background here.

Obviously, the files mentioned in the manifest must be created in the same folder.

The last item in the manifest is the commands object. For each command you need to define the id, the keyboard shortcut (only the 0..9 and A..Z are usable unfortunately) and a description. In order to respond to commands you need a background page as shown above.

2. Test the extension


Next you open a Chrome tab and go to chrome://extensions, click on the 'Developer mode' checkbox if it is not checked already and you get a Load unpacked extension button. Click it and point the following dialog to your folder and test that everything works OK.

3. Publish your extension


In order to publish your extension you need to have a Chrome Web Store account. Go to Chrome Web Store Developer Dashboard and create one. You will need to pay a one time 5$ fee to open it. I know, it kind of sucks, but I paid it and was done with it.

Next, you need to Add New Item, where you will be asked for a packed extension, which is nothing but the ZIP archive of all the files in your folder.

That's it.

Let's now discuss actual implementation details.

Adding functionality to popup elements


Getting the popup page elements is easy with vanilla Javascript, because we know we are building for only one browser: Chrome! So getting elements is done via document.getElementById(id), for example, and adding functionality is done via elem.addEventListener(event,handler,false);

One can use the elements as objects directly to set values that are related to those elements. For example my prev/next button functionality takes the URL from the button itself and changes the location of the current tab to that value. Code executed when the popup opens sets the 'url' property on the button object.

Just remember to do it when the popup has finished loading (with document.addEventListener('DOMContentLoaded', function () { /*here*/ }); )

Getting the currently active tab


All the Chrome APIs are asynchronous, so the code is:
chrome.tabs.query({
'active' : true,
'lastFocusedWindow' : true
}, function (tabs) {
var tab = tabs[0];
if (!tab) return;
// do something with tab
});

More on chrome.tabs here.

Changing the URL of a tab


chrome.tabs.update(tab.id, {
url : url
});

Changing the icon in the Chrome extensions bar


if (chrome.browserAction) chrome.browserAction.setIcon({
path : {
'19' : 'anotherIcon.png'
},
tabId : tab.id
});

The icons are 19x19 PNG files. browserAction may not be available, if not declared in the manifest.

Get bookmarks


Remember you need the bookmarks permission in order for this to work.
chrome.bookmarks.getTree(function (tree) {
//do something with bookmarks
});

The tree is an array of items that have title and url or children. The first tree array item is the Bookmarks Bar, for example. More about bookmarks here.

Hooking to Chrome events


chrome.tabs.onUpdated.addListener(refresh);
chrome.tabs.onCreated.addListener(refresh);
chrome.tabs.onActivated.addListener(refresh);
chrome.tabs.onActiveChanged.addListener(refresh);
chrome.contextMenus.onClicked.addListener(function (info, tab) {
navigate(info.menuItemId, tab);
});
chrome.commands.onCommand.addListener(function (command) {
navigate(command, null);
});

In order to get extended info on the tab object received by tabs events, you need the tabs permission. For access to the contextMenus object you need the contextMenus permission.

Warning: if you install your extension from the store and you disable it so you can test your unpacked extension, you will notice that keyboard commands do not work. Seems to be a bug in Chrome. The solution is to remove your extension completely so that the other version can hook into the keyboard shortcuts.

Creating, detecting and removing menu items


To create a menu item is very simple:
chrome.contextMenus.create({
"id" : "menuItemId",
"title" : "Menu item description",
"contexts" : ["page"] //where the menuItem will be available
});
However, there is no way to 'get' a menu item and if you try to blindly remove a menu item with .remove(id) it will throw an exception. My solution was to use an object to store when I created and when I destroyed the menu items so I can safely call .remove().

To hook to the context menu events, use chrome.contextMenus.onClicked.addListener(function (info, tab) { }); where info contains the menuItemId property that is the same as the id used when creating the item.

Again, to access the context menu API, you need the contextMenus permission. More about context menus here.

Commands


You use commands basically to define keyboard shortcuts. You define them in your manifest and then you hook to the event with chrome.commands.onCommand.addListener(function (command) { });, where command is a string containing the key of the command.

Only modifiers, letters and digits can be used. Amazingly, you don't need permissions for using this API, but since commands are defined in the manifest, it would be superfluous, I guess.

That's it for what I wanted to discuss here. Any questions, bug reports, feature requests... use the comments in the post.

In the previous post I was discussing Firebase, used in Javascript, and that covered initialization, basic security, read all and insert. In this post I want to discuss about complex queries: filtering, ordering, limiting, indexing, etc. For that I will get inspiration (read: copy with impunity) from the Firebase documentation on the subject Retrieving Data, but make it quick and dirty... you know, like sex! Thank you, ma'am!

OK, the fluid interface for getting the data looks a lot like C# LInQ and I plan to work on a Linq2Firebase thing, but not yet. Since LInQ itself got its inspiration from SQL, I was planning to structure the post in a similar manner: how to do order by, top/limit, select conditions, indexing and so on, so we can really use Firebase like a database. An interesting concept to explore is joining, since this is an object database, but we still need it, because we want to filter by the results of the join before we return the result, like getting all the transaction of users that have the name 'Adam'. Aggregating is another thing that I feel Firebase needs to support. I don't want a billion records in order to compute the sum of a property.

However, the Firebase API is rather limited at the moment. You get .orderByChild, then stuff like .equalTo, .startAt and .endAt and then .limitToFirst and .limitToLast. No aggregation, no complex filters, no optimized indexing, no joining. As far as I can see, this is by design, so that the server is as dumb as possible, but think about that 1GB for the free plan. It is a lot.

So, let's try a complex query, see were it gets us.
ref.child('user')
.once('value',function(snapshot) {
var users=[];
snapshot.forEach(function(childSnapshot) {
var item=childSnapshot.val();
if (/adam/i.test(item.name)) {
users.push(item.userId);
}
});
getInvoiceTotalForUsers(users,DoSomethingWithSum);
});


function getInvoiceTotalForUsers(users,callback)
{
var sum=0;
var count=0;
for (var i=0; i<users.length; i++) {
var id=users[i];
ref.child('invoice')
.equalTo(id,'userId')
.orderByChild('price')
.startAt(10)
.endAt(100)
.once('value',function(snapshot) {
snapshot.forEach(function(childSnapshot) {
var item = childSnapshot.val();
sum+=item.price;
count++;
if (count==users.length) callback(sum);
});
});
}
}

First, I selected the users that have 'adam' in the name. I used .once instead of .on because I don't want to wait for new data to arrive, I want the data so far. I used .forEach to enumerate the data from the value event. With the array of userIds I call getInvoiceTotalForUsers, which gets all the invoices for each user, with a price bigger or equal to 10 and less or equal to 100, which finally calls a callback with the resulting sum of invoice prices.

For me this feels very cumbersome. I can think of several methods to simplify this, but the vanilla code would probably look like this.

I have been looking for a long time for this kind of service, mainly because I wanted to monitor and persist stuff for my blog. Firebase is all of that and more and, with a free plan of 1GB, it's pretty awesome. However, as it is a no SQL database and as it can be accessed via Javascript, it may be a bit difficult to get it at first. In this post I will be talking about how to use Firebase as a traditional database using their Javascript library.

So, first off go to the main website and signup with Google. Once you do, you get a page with a 5 minute tutorial, quickstarts, examples, API docs... but you want the ultra-quick start! Copy pasted working code! So click on the Manage App button.

Take note of the URL where you are redirected. It is the one used for all data usage as well. Ok, quick test code:
var testRef = new Firebase('https://*******.firebaseio.com/test');
testRef.push({
val1: "any object you like",
val2: 1,
val3: "as long as it is not undefined or some complex type like a Date object",
val4: "think of it as JSON"
});
What this does is take that object there and save it in your database, in the "test" container. Let's say it's like a table. You can also save objects directly in the root, but I don't recommend it, as the path of the object is the only one telling you what type of object it is.

Now, in order to read inserted objects, you use events. It's a sort of reactive way of doing things that might be a little unfamiliar. For example, when you run the following piece of code, you will get after you connect all the objects you ever inserted into "test".
var testRef = new Firebase('https://*******.firebaseio.com/test');
testRef.on('child_added', function(snapshot) {
var obj = snapshot.val();
handle(obj); //do what you want with the object
});

Note that you can use either child_added or value, as the retrieve event. While 'child_added' is fired on each retrieved object, 'value' returns one snapshot containing all data items, then proceeds to fire on each added item with full snapshots. Beware!, that means if you have a million items and you do a value query, you get all of them (or at least attempt to, I think there are limits), then on the next added item you get a million and one. If you use .limitToLast(50), for example, you will get the last 50 items, then when a new one is added, you get another 50 item snapshot. In my mind, 'value' is to be used with .once(), while 'child_added' with .on(). More details in my Queries post

Just by using that, you have created a way to insert and read values from the database. Of course, you don't want to leave your database unprotected. Anyone could read or change your data this way. You need some sort of authentication. For that go to the left and click on Login & Auth, then you go to Email & Password and you configure what are the users to log in to your application. Notice that every user has a UID defined. Here is the code to use to authenticate:
var testRef = new Firebase('https://*******.firebaseio.com/test');
testRef.authWithPassword({
email : "some@email.com",
password : "password"
}, function(error, authData) {
if (error) {
console.log("Login Failed!", error);
} else {
console.log("Authenticated successfully with payload:", authData);
}
});
There is an extra step you want to take, secure your database so that it can only be accessed by logged users and for that you have to go to Security & Rules. A very simple structure to use is this:
{
"rules": {
"test": {
".read": false,
".write": false,
"$uid": {
// grants write access to the owner of this user account whose uid must exactly match the key ($uid)
".write": "auth !== null && auth.uid === $uid",
// grants read access to any user who is logged in with an email and password
".read": "auth !== null && auth.provider === 'password'"
}
}
}
}
This means that:
  1. It is forbidden to write to test directly, or to read from it
  2. It is allowed to write to test/uid (remember the user UID when you created the email/password pair) only by the user with the same uid
  3. It is allowed to read from test/uid, as long as you are authenticated in any way

Gotcha! This rule list allows you to read and write whatever you want on the root itself. Anyone could just waltz on your URL and fill your database with crap, just not in the "test" path. More than that, they can just listen to the root and get EVERYTHING that you write in. So the correct rule set is this:
{
"rules": {
".read": false,
".write": false,
"test": {
".read": false,
".write": false,
"$uid": {
// grants write access to the owner of this user account whose uid must exactly match the key ($uid)
".write": "auth !== null && auth.uid === $uid",
// grants read access to any user who is logged in with an email and password
".read": "auth !== null && auth.provider === 'password'"
}
}
}
}

In this particular case, in order to get to the path /test/$uid you can use the .child() function, like this: testRef.child(authData.uid).push(...), where authData is the object you retrieve from the authentication method and that contains your logged user's UID.

The rule system is easy to understand: use ".read"/".write" and a Javascript expression to allow or deny that operation, then add children paths and do the same. There are a lot more things you could learn about the way to authenticate: one can authenticate with Google, Twitter, Facebook, or even with custom tokens. Read more at Email & Password Authentication, User Authentication and User Based Security.

But because you want to do a dirty little hack and just make it work, here is one way:
{
"rules": {
".read": false,
".write": false,
"test": {
".read": "auth.uid == 'MyReadUser'",
".write": "auth.uid == 'MyWriteUser'"
}
}
}
This tells Firebase that no one is allowed to read/write except in /test and only if their UID is MyReadUser, MyWriteUser, respectively. In order to authenticate for this, we use this piece of code:
testRef.authWithCustomToken(token,success,error);
The handlers for success and error do the rest. In order to create the token, you need to do some cryptography, but nevermind that, there is an online JsFiddle where you can do just that without any thought. First you need a secret, for which you go into your Firebase console and click on Secrets. Click on "Show" and copy paste that secret into the JsFiddle "secret" textbox. Then enter MyReadUser/MyWriteUser in the "uid" textbox and create the token. You can then authenticate into Firebase using that ugly string that it spews out at you.

Done, now you only need to use the code. Here is an example:
var testRef = new Firebase('https://*****.firebaseio.com/test');
testRef.authWithCustomToken(token, function(err,authData) {
if (err) alert(err);
myDataRef.on('child_added', function(snapshot) {
var message = snapshot.val();
handle(message);
});
});
where token is the generated token and handle is a function that will run with each of the objects in the database.

In my case, I needed a way to write messages on the blog for users to read. I left read access on for everyone (true) and used the token idea from above to restrict writing. My html page that I run locally uses the authentication to write the messages.

There you have it. In the next post I will examine how you can query the database for specific objects.

I have implemented a system that logs what people do on my blog, with the intent of making it more useful to my readers. In doing so I created a live dashboard where people going and leaving are displayed in real time. The conclusion is pretty humbling, but I have also noticed a pattern that might reflect badly on the state of the Internet today.

The conclusion I was talking about is that, even if I write about a lot of things, from books to software, from WPF to Javascript, the most visited posts by far are about why the Bittorrent client gets stuck, how to remove ads by installing Privoxy and Sift3, my string comparison algorithm. All of that info one can get from the Popular posts column in the right of the blog, but I had no idea how many people visit it only to find how they can download their movies faster!

And then there are the programming blog posts. I am filled with pride when people open a link to learn something from my experiences. And then I see that they are looking at the posts about Crystal Reports, AjaxControlToolkit and the old ASP.Net Ajax calls. Occasionally they come for the WPF bit, which is great, but the conclusion is clear: people are mostly interested in the old posts, the ones describing older technologies that no one is talking about anywhere anymore. True, I have not posted anything significant in the last two years, but still, I feel disappointed. My blog's merit here seems to be that it is still online!

But then I realized something else. Sometimes I feel joy at seeing that a visitor opens a post that no one has opened recently. Yet, in a very short time, other people are starting to open the same link. It has happened repeatedly several days in a row, so it can't be a coincidence. And people are coming from all over: Canada, US, Brazil, Mozambique, Ghana! I can only explain it with the theory that once visited, a link increases in visibility, its Google rank goes up, thus passing a threshold that makes it appear on the first search pages. It is a snowball effect, which in part I understand and agree with, but can't stop wondering if it doesn't apply everywhere. Instead of going for the relevance that Google and other big search engines aspire towards, they cheat by treating each click as a Facebook Like! More people read it, so more people should read it, which they do, and so on and so on.

The bottom line is that I wouldn't want to see a race towards a common goal be treated as a common race towards a goal. Let all pages share the glory, rank them based on content, not the preferences of people searching for stuff. How long before Google will helpfully suggest to me to go download a movie rather than search for something for work?

Today I wanted to read a PDF. Nothing more than that, just read a damn file. Instead, I got the first use of the Adobe Reader DC, which I may have inadvertently updated to when asked for an update (rather than a complete redesign). But I was OK with it, you know. Adobe Reader was always a lightweight reader of files and the updates have mostly been about security. So now they want to redesign it, what could possibly go wrong? Just rearrange some menus or something, right? Wrong.

I skipped EULAs and bloating features for a while until I got to (surprise!) an online login screen. I didn't want to log in anywhere, I just wanted to read the PDF, so I closed the login popup window. It reopened. I started looking for buttons or links for skipping, cancelling, ignoring, doing it later, but none were there. Quite literally I was locked until I chose to log in. You know what I did? I forcefully closed the process and installed Sumatra PDF reader. 10 seconds later I was reading my damn PDF.

And you know what? I have used Sumatra PDF on other computers in the past. What I found is that, besides some features for PDF that I will never use, like forms and such, Sumatra was better than Adobe Reader. Way faster, that's obvious, but then it read correctly some PDFs that could not be even opened by the default reading application from the company that invented the damn document standard. Once, I remember, we had a weird PDF that we had to wait for about a minute in Adobe Reader in order to render a single page. Sumatra opened it instantly. Not only it is smaller, leaner, faster, better, but Sumatra also reads a lot of other formats: ePub, MOBI, CHM, XPS, DjVu, CBZ, CBR.

Bottom line: I have abandoned the last Adobe tool that I was regularly using on my computer. Will they ever learn?

Whenever you want to test a REST API, Postman is a great tool. It allows configuring all aspects of a request: Method (GET, POST, etc), Headers, keeps previous attempts in history, manages collections of requests and saves them and it is installed as a Chrome extension, bringing it only two clicks away. It does everything! ... or does it? Short story long: no!

Reported as a problem here: Referer header is not sent when set in Postman, the issue appears to be that some headers are "protected" by Chrome, therefore unusable. Well, it is a bug in the sense that Postman should tell you that when you write something there it is completely ignored! There is a solution, that can be found as a link in the bug report, but it involves installing other crap and running Python scripts. Ugh!

Here is a list of the Chrome protected headers:
  • Accept-Charset
  • Accept-Encoding
  • Access-Control-Request-Headers
  • Access-Control-Request-Method
  • Connection
  • Content-Length
  • Cookie
  • Cookie 2
  • Content-Transfer-Encoding
  • Date
  • Expect
  • Host
  • Keep-Alive
  • Origin
  • Referer
  • TE
  • Trailer
  • Transfer-Encoding
  • Upgrade
  • User-Agent
  • Via

So whenever you believe that some web site has used a magical solution to detect your sneaky attempts to access their web API or site and you are wondering what, just remember that it is most likely a Referer header that Postman (via Chrome) silently ignored.

I was trying to do a simple thing: configure a daily rolling log for log4net, meaning that I wanted that log files would be created daily and the name of the files would contain the date. The log was already configured and working with a normal FileAppender, so all I had to do was find the correct configuration. There are several answers on the Internet regarding this. I immediately went to the trusty StackOverflow and read the first answers, copy pasted lazily, and it seemed to work. But it did not. So warning, the first answer on StackOverflow about this is wrong.

So, my logs had to be named something like Application_20150420.log. That means several things:
  • The name of the appender class has to be set to log4net.Appender.RollingFileAppender
  • The name of the log files need to start with Application_ and end in .log
  • The name of the log files need to contain the date in the correct format
  • The logger needs to know that the files need to be created daily

This is the working configuration:
<appender name="FileAppender" type="log4net.Appender.RollingFileAppender">
<filter type="log4net.Filter.LevelRangeFilter">
<acceptOnMatch value="true" />
<levelMin value="DEBUG" />
</filter>

<file type="log4net.Util.PatternString" value="c:\logfiles\Application_.log" />
<appendToFile value="true" />
<rollingStyle value="Date" />
<datePattern value="yyyyMMdd" />
<preserveLogFileNameExtension value="true"/>
<staticLogFileName value="false" />

<lockingModel type="log4net.Appender.FileAppender+MinimalLock"/>
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date %-5level %logger - %message%newline"/>
</layout>
</appender>

As you can see, it is a little counter-intuitive. You do not need to specify the date in the file name, it will be added automatically, and you absolutely need to use preserveLogFileNameExtension, otherwise your files would look like Application_.log20140420

Because of idiotic firewall rules at my workplace I am forced to use Hangouts rather than Yahoo Messenger as an instant messenger. I am not going to rant here about which one is best, enough to say that most of my friends are on YM and being on Hangouts doesn't help. Hangouts has many annoyances for me, like its propensity to freeze when you lose Internet connection often or the lack of features that YM had. In fact I was so annoyed that I planned to do my own professional messenger to rule them all. But that's another story.

I am writing this post because of a behaviour of the Google Hangouts instant messenger (which, to be fair, is only a Chrome extension), mainly that after a while, the green traybar icon of the messenger goes in the "hidden icons" group. I have to customize it every day, sometimes twice, as it seems to reset this behavior after a period of use, not just on restarts. There is a Google product forum that discusses this here: System tray icon resets every time Chrome is started where you also see a few comments from your truly.

I immediately wanted to create a script or a C# program to fix this, but at first I just searched for a solution on the web and I found TrayManager, a C# app that does what the "Customize..." tray link does and more. One of the best features is a command line! So here is what you do after downloading the software and installing it somewhere: TrayManager.exe -t "Hangouts" 2. Now, probably that doesn't solve the problem long term. It is just as you would go into the Customize... link, but it's faster. Also, it has no side effects if run multiple times, so you can use Task Scheduler to run it periodically. Yatta!

I've heard of for some time now, but never actually tried anything on the site. Today I tried a course that teaches the basics of R, a statistics programming language akin to Matlab, and I thought the site was great. I suspect it all depends on the quality of the course, but at least this one was very nice. You can see my "report card" here, although I doubt I am going to visit the site very often. However, for beginners or people who quickly want to "get" something, it is a good place to start, as it gives one a "hands on" experience, like actually coding to get results, but in a carefully explained step by step tutorial format.

I have at work a very annoying HTTP proxy that requires a basic authentication. This translates in very inconsistent behaviour between applications and the annoying necessity of entering the username and password whenever the system wants it. So I've decided to add another local proxy to the chain that handles the authentication for me forever.

This isn't as easy as it sounds. Sure, proxies are a dime a dozen, but for some reason most of them seem to be coming from the Linux world. That is really bad user interaction, vague documentation and unhelpful forums where any request for help ends up in some version of "read the fucking manual". Hence I've decided to help out by creating this lovely post that explains how you can achieve the purpose described above with very little headache. These are the very easy steps that you have to undertake:
  1. Download and install Privoxy
  2. Go to the Program Files folder and look for Privoxy. You will need to edit two files: config.txt and user.action
  3. Optional: change the listen-address port, otherwise the proxy will function on port 8118
  4. Enter your proxy authentication username and password in the fields below and press Help me configure Privoxy - this is strictly a client base Javascript so don't worry that I am going to steal your proxy credentials...
  5. Edit user.action and add the bit of text that appeared as destined for that file.
  6. Edit config.txt, look for examples of forward and add to it the bit that belongs to config.txt and replace proxy:port and the domains and IP masks with the correct values for you
  7. Restart Privoxy
  8. Configure your internet settings to use a proxy on 127.0.0.1 and the port you configured in step 2 (or the default 8118)

This should be it. Enjoy!

Username:
Password:


I realize that the original format of the post was confusing, so, before you start reading it, here is a summary of solutions. You should read on afterwards in order to understand the context of each solution in part, though:
  • Torrents seem to keep a reference to some of the proxy settings when they started downloading. I don't have a clear solution for this, in my case changing the configuration of the proxy and restarting both proxy and Bittorrent eventually solved it. An aggressive solution is to remove all of your torrents and readd them later.
  • Sometimes the settings file gets corrupted or the settings don't make a lot of sense. Save all your ongoing downloads, remember all the relevant settings - like download folder -, stop Bittorrent, go to your user's Application Data folder and remove the settings.dat and settings.dat.old files in the Bittorrent folder. (usually C:\Documents and Settings\YourUser\Application Data\Bittorrent or.and C:\Users\YourUser\Application Data\Bittorrent). After restarting Bittorrent you will have a fresh set of settings, so change them to what you need and reload the list of torrents that you saved.
  • Check the connection settings. Sometimes you want to minimize the number of connections Bittorrent makes because your provider gives you only a limited connection pool. Make sure the value is not too small. Bittorrent needs a lot of connections: to find peers, to download and upload stuff, to open new connections in order to find the faster one, etc. In my case 15 was too little and I had to restore it to the original 150, even it 15 worked with previous versions of the program.
  • Solution from a comment: check your firewall settings and the firewall settings of your router/modem
  • Solution from a comment: check your internet provider. Some, like Comcast, are throttling some types of traffic. This link might help: Stop your ISP from Throttling Bittorrent Speeds
  • Solution from a comment: enable Bittorrent protocol encryption and restart the application
  • Solution from a forum: disable DHT from the Bittorrent client settings (or enable it, if it is disabled?)
  • Solution from YouTube: start the torrent client 'As Administrator', suggesting there may be some file access issues you have.
  • Solution from a comment: enable DHT. If only some torrents seem to be stuck, see if you can enable DHT in those torrents' properties.

Hope that helps. Now for the original post:

Update (again): While resetting the settings did solve my problem temporarily, I had the same problem the next day as well. The only meaningful thing that I had changed was the global maximum number of connections (Preferences -> Bandwith) from 150, which seemed excessive, to 15. I changed the value back to 150 and it started downloading immediately! This is strange, since the value was 15 for years, I think. Well, I am getting tired of these solutions that only work until the next day. Hopefully this is the last time the problem appears.

Update: The enthusiasm I had after making some of the torrents work faded when I noticed most of the other torrents were still not working. My only solution was to go to the Application Data folder, then Bittorrent, and delete settings.dat and settings.dat.old while the program was closed, then restart Bittorrent. Warning! You will lose all the torrents and settings so save them first (I selected them all and copied the magnet links, then added them back one by one afterwards). The weird thing is that, while it worked, the software also looked quite different from what I was used to. Perhaps just blindly updating the version of Bittorrent all the time is not the best option. Sometimes we need to reset the setting to take advantage of the new software settings.

I've had a problem with a router which prompted me to remove it and put the Internet cable directly into my computer port. I wouldn't recommend it for you, since a router adds a level of protection against outside access, but still, I was not home and a friend of mine "fixed" the problem. Since then, I couldn't download anything on Bittorrent, as it got stuck at "Connecting to peers", even if it connected to the trackers, and saw all the seeds and leechers. Googling around I found a suggestion to remove "resume.dat" from the Bittorrent Application Data folder, but it didn't work for me. I tried a lot of things, but none worked until I found an obscure forum asking about a proxy server. And it dawned on me that it could be from there.
You see, I had previously installed a free proxy program called Privoxy, but I had bound it to the previous IP address of the computer. As a result, it didn't load anymore. The Internet settings were OK, I had removed any reference to a proxy, but strangely enough something in the Bittorrent client kept some information relating to the proxy. After I only bound the proxy to the local address, Privoxy started and miraculously also did the Bittorrent downloads (after a restart of the program).

So, if you have issues with the Bittorent client getting stuck at "Connecting to peers", check if you have recently changed your Internet proxy settings.

Update 12 Feb 2016: As an alternative, if you have access to your hosts file, you can use a generated list of domains to immediately block any access to those IPs, courtesy of Steven Black: StevenBlack/hosts, and you don't have to install anything and works on most operating systems.

Update 19 Feb 2016: Here are the latest files to directly download and use. Do read the rest of the article, as these files might not be what you are looking for:
user.action
user.filter

Now for the rest of the article:

I discovered today a new tool called Privoxy. It is a proxy software that has extra features, like ad blocking and extra privacy. What that means is that you can install the proxy, point your browser to that proxy and have an almost ad free untracked by marketing firms or FaceBook experience. The only problem, though, is that the default filters are not so comprehensive. Would it be great if one could take the most used list for ad blocking (Adblock Plus' Easylist) and convert it to Privoxy? Well it would, only that no one seems to want to do it for Windows. You get a few folks that have created Linux scripts to do the conversion, but they won't work for Windows. Nor do they deem it necessary to make an online tool or a web service or at least publish the resulting files so that we, Windows people, can also use the list!

Well, I intend to do a small script that will allow for this, preferably embedded in this blog post, but until then, I had no script, no files, only Privoxy installed. Luckily, I also have Cygwin installed, which allows me to run a ridiculous flavour of Linux inside Windows. I had to hack the script in order for it to work on Cygwin, but in the end, at last, I managed to make it work. For now, I will publish the resulting files here and give you instructions to install them. When they become obsolete, send me a comment and I will refresh them.

So, the instructions:
  • Install Privoxy
  • Go to the installation folder of Privoxy and look for files named 'user.action' and 'user.filter'
  • Download the user.action file from here and replace the default one.
  • Download the user.filter file from here and replace the default one.
  • Restart Privoxy
  • Of course, then you have to go to your browser settings and set the proxy to Privoxy (usually localhost, port 8118)

Warning! The filter file is quite big and it will cause some performance issues. You might want to use only the action file with the filter actions removed.

Update: If you can't download the files, let me know. I am using Github pages and it seems sometimes it doesn't work as I expected.

Also, I have lost faith that AdBlockPlus rules can be completely and correctly translated to Privoxy and I lack the time, so I am publishing my crappy program as it is and if you want to use it or fix it, be my guest. You can find the program here: AdblockPlus to Privoxy. I would ask that you share with me those modifications, though, so that everybody can benefit from them.

Update October 2014: Other people have contributed by making their own translation software. Here are the links for the binary and source code of adblock2privoxy made by Zubr, in Haskell mind you, which is pretty cool:

Binary: https://www.dropbox.com/s/69u1iqbubzft1yl/adblock2privoxy-1.2.4.rar?dl=0
Source code: https://projects.zubr.me/wiki/adblock2privoxy