How To Call WCF Services Properly

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No matter how many client sites I visit, invariably I stumble across Windows Communication Foundation (WCF) client-side code that leaks memory and resources. This can result in an application crashing or connection limits being reached resulting in further service calls being rejected. Not only can the client-side code cause problems on the client machine, but if connections are not correctly closed on the client then that can cause the server to hit its maximum connection limit and reject service calls from other clients as well!

These types of issues are caused by developers performing incorrect error handling and incorrect disposal of the client and connection. Microsoft really is to blame for starting this mess, as they created an API that does not conform to typical practices - or even their own guidelines! For instance, Microsoft's guideline is never to throw an exception from a Dispose method - but the WCF client code does exactly that. At the end of the day however, it is the responsibility of individual developers to be aware of the issues and design restrictions and create software that works properly.

In many cases, WCF client-side code resides in small or medium-sized user applications that do not get used hard or long enough to exhibit a noticeable degradation in system resources and upset users. But as previously stated, depending on the number of users, it still may be causing issues on servers.

When it goes wrong - for instance, on a server - there can be a spectacular flurry of activity! It can be amazing to see how quickly IT departments can move when a server hosting core business services starts failing due to custom server applications leaking resources and using many Gigabytes of memory. Unfortunately it takes such an event for many businesses to pay attention to the need for higher-quality software development practices and testing.

In the past I have seen proud companies who develop and sell custom n-tier products "work around" known problems in their proprietary code by recommending to their clients that they recycle the IIS Application Pools frequently and run an excessive numbers of servers. I never really appreciated that band-aid attitude towards software development practices or clients.

This series of articles will show you how to fix the root cause - by correctly calling WCF services, handling errors and disposing of WCF clients.

Update 2014-10-01: The focus of this article is not about the overall design of WCF. Other parts of WCF are designed very well - especially with regards to its extensible nature. This article is a narrow focus on the design decisions that cause the common issues I see too often on so many client sites.

The Problems

The "Using" Statement and Understanding States

One of the problems that Microsoft caused was by not following their own guideline of not throwing exceptions in the Dispose method. The using statement is an excellent and common pattern for automatically disposing IDisposable objects at the end of the code block. Avoiding Problems with the Using Statement describes how even though the WCF client is disposable, developers should NOT use the using statement with them.

The C# "using" statement results in a call to Dispose(). This is the same as Close(), which may throw exceptions when a network error occurs. Because the call to Dispose() happens implicitly at the closing brace of the "using" block, this source of exceptions is likely to go unnoticed both by people writing the code and reading the code. This represents a potential source of application errors.

Microsoft demonstrates in that article how to clean up "correctly" when an exception occurs.

try
{
    ...
    client.Close();
}
catch (CommunicationException e)
{
    ...
    client.Abort();
}
catch (TimeoutException e)
{
    ...
    client.Abort();
}
catch (Exception e)
{
    ...
    client.Abort();
    throw;
}

It is important to understand that if the client is in a State of Faulted, then the only action that should be taken by client code is the Abort method. As documented in Expected Exceptions the TimeoutException, CommunicationException and any derived class of CommunicationException are 'expected' exceptions from the WCF client.

If an expected exception occurs, the client may or may not be usable afterwards. To determine if the client is still usable, check that the State property is CommunicationState.Opened. If it is still opened, then it is still usable. Otherwise you should abort the client and release all references to it.

Caution: You may observe that clients that have a session are often no longer usable after an exception, and clients that do not have a session are often still usable after an exception. However, neither of these is guaranteed, so if you want to try to continue using the client after an exception your application should check the State property to verify the client is still opened.

Code that calls a client communication method must catch the TimeoutException and CommunicationException.

However, all this talk of checking for the State property is cautioned by Accessing Services Using a WCF Client:

Checking the value of the ICommunicationObject.State property is a race condition and is not recommended to determine whether to reuse or close a channel.

If you were to check the State property in order to determine whether to Abort or Close, depending on your approach there could be a race condition. For instance the following code could result in a race condition:

if (this.State == CommunicationState.Faulted) 
{ 
    this.Abort();
}
else 
{
    this.Close();
}

The race condition could occur because when the State property is checked to see if it is Faulted it might be Opened at that point in time. However, by the short time that Close method is reached, the State might now be Faulted, and when Close is called an exception would be thrown. This code alone is not sufficient.

The Communication State Enumeration documentation explains the meaning of each possible State:

The Closed state is equivalent to being disposed and the configuration of the object can still be inspected.

The Faulted state is used to indicate that the object has transitioned to a state where it can no longer be used. There are two primary scenarios where this can happen:

  • If the Open method fails for any reason, the object transitions to the faulted state.
  • If a session-based channel detects an error that it cannot recover from, it transitions to the faulted state. This can happen for instance if there is a protocol error (that is, it receives a protocol message at an invalid time) or if the remote endpoint aborts the session.

An object in the Faulted state is not closed and may be holding resources. The Abort method should be used to close an object that has faulted. If Close is called on an object in the Faulted state, a CommunicationObjectFaultedException is thrown because the object cannot be gracefully closed.

The article Understanding State Changes describes how the State property can transition to different states. This article expands upon and somewhat contradicts the previous by indicating that if the object is in the Faulted state then the Close method will call Abort for you and return.

The Close() method can be called at any state. It tries to close the object normally. If an error is encountered, it terminates the object. The method does nothing if the current state is Closing or Closed. Otherwise it sets the state to Closing. If the original state was Created, Opening or Faulted, it calls Abort().

I'm confused - how about you?

To remedy my confusion, I went to the source of truth - the code. The reference source for CommunicationObject shows us that the Close method handles being called from any State value, and that it will perform an Abort if required. In addition, if the State was Faulted, the Close method actually will throw a CommunicationObjectFaultedException.

...
               switch (originalState)
                {
                    case CommunicationState.Created:
                    case CommunicationState.Opening:
                    case CommunicationState.Faulted:
                        this.Abort();
                        if (originalState == CommunicationState.Faulted)
                        {
                            throw TraceUtility.ThrowHelperError(this.CreateFaultedException(), Guid.Empty, this);
                        }
                        break;
...

The article Understanding State Changes also explicitly states that the Abort method can throw exceptions.

The Abort() method does nothing if the current state is Closed or if the object has been terminated before (for example, possibly by having Abort() executing on another thread). Otherwise it sets the state to Closing and calls OnClosing() (which raises the Closing event), OnAbort(), and OnClosed() in that order (does not call OnClose because the object is being terminated, not closed). OnClosed() sets the state to Closed and raises the Closed event. If any of these throw an exception, it is re-thrown to the caller of Abort.

No sample code from Microsoft or anywhere else that I have seen handles the situation where the Abort method throws an exception.

Stack Overflow has an interesting thread about how to work around the using block issue and perform the close/abort pattern. Their top-voted solution for the close/abort pattern, to fix the race condition is:

bool success = false; 
try 
{
    if (State != CommunicationState.Faulted) 
    {
        Close(); 
        success = true;
    }
}
finally 
{ 
    if (!success) 
    {
        Abort();
    }
}

In this code, if the State is already Faulted or the execution of the Close method throws an exception (which is implicitly caught and ignored), then finally the Abort method will be called. That's pretty good. But as we now know, the Abort method can throw exceptions, and that code does not handle it.

Exception Catching Order

The article Sending and Receiving Faults shows us that we need to catch the exceptions in a specific order - especially in relation to the SOAP-based FaultException.

Because FaultException derives from FaultException, and FaultException derives from CommunicationException, it is important to catch these exceptions in the proper order. If, for example, you have a try/catch block in which you first catch CommunicationException, all specified and unspecified SOAP faults are handled there; any subsequent catch blocks to handle a custom FaultException exception are never invoked.

Remember that one operation can return any number of specified faults. Each fault is a unique type and must be handled separately.

Closing the channel can throw exceptions if the connection cannot be cleanly closed or is already closed, even if all the operations returned properly.

Typically, client object channels are closed in one of the following ways:

  • When the WCF client object is recycled.
  • When the client application calls ClientBase.Close.
  • When the client application calls ICommunicationObject.Close.
  • When the client application calls an operation that is a terminating operation for a session.

In all cases, closing the channel instructs the channel to begin closing any underlying channels that may be sending messages to support complex functionality at the application level. For example, when a contract requires sessions a binding attempts to establish a session by exchanging messages with the service channel until a session is established. When the channel is closed, the underlying session channel notifies the service that the session is terminated. In this case, if the channel has already aborted, closed, or is otherwise unusable (for example, when a network cable is unplugged), the client channel cannot inform the service channel that the session is terminated and an exception can result.

Abort the Channel If Necessary

Because closing the channel can also throw exceptions, then, it is recommended that in addition to catching fault exceptions in the correct order, it is important to abort the channel that was used in making the call in the catch block. If the fault conveys error information specific to an operation and it remains possible that others can use it, there is no need to abort the channel (although these cases are rare). In all other cases, it is recommended that you abort the channel. For a sample that demonstrates all of these points, see Expected Exceptions.

And here is the sample code from that article:

using System;
using System.ServiceModel;
using System.ServiceModel.Channels;
using Microsoft.WCF.Documentation;

public class Client
{
  public static void Main()
  {
    SampleServiceClient wcfClient = new SampleServiceClient();

    try
    {
      wcfClient.SampleMethod("hello");

      wcfClient.Close();
    }
    catch (TimeoutException timeProblem)
    {
      wcfClient.Abort();
    }
    catch (FaultException<MyCustomFault> myCustomFault)
    {
      wcfClient.Abort();
    }
    catch (FaultException<MyOtherCustomFault> myOtherCustomFault)
    {
      wcfClient.Abort();
    }
    catch (FaultException unknownFault)
    {
      wcfClient.Abort();
    }
    catch (CommunicationException commProblem)
    {
      wcfClient.Abort();
    }
  }
}

Note the following about this sample code:

  • The client is not closed or aborted if there is an unexpected exception; and
  • There is no concern about catching exceptions from the Abort method.

Other Exceptions

There is one more type of exception that never seems to be mentioned in sample code or in any literature I have seen related to WCF, and that is the ThreadAbortException.

When this exception is raised, the runtime executes all the finally blocks before ending the thread. Because the thread can do an unbounded computation in the finally blocks or call Thread.ResetAbort to cancel the abort, there is no guarantee that the thread will ever end.

The ThreadAbortException is a special exception that can occur asynchronously. If the WCF client is called from within a thread, and if the thread is aborted, then it might be prudent to clean up the client before the thread finishes.

The top-voted solution from Stack Overflow does partially and elegantly handle this situation, as well as the other asynchronous exceptions such as OutOfMemoryException and StackOverflowException.

Oh My!

So does all that sound complicated enough? No wonder so many don't get it right...

How To Do It Correctly?

In my opinion, the most correct solution would:

  • Perform the Close/Abort pattern without a race condition
  • Handle the situation when the service operation throws exceptions
  • Handle the situations when both the Close and Abort methods throw exceptions
  • Handle asynchronous exceptions such as the ThreadAbortException

Below is my proposed solution for correctly using a WCF client.

SampleServiceClient client = null;

try
{
    client = new SampleServiceClient();

    var response = client.SampleOperation(1234);

    // Do some business logic
}
catch (FaultException<MyCustomException>)
{
    // Do some business logic for this SOAP Fault Exception
}
catch (FaultException)
{
    // Do some business logic for this SOAP Fault Exception
}
catch (CommunicationException)
{
    // Catch this expected exception so it is not propagated further.
    // Perhaps write this exception out to log file for gathering statistics...
}
catch (TimeoutException)
{
    // Catch this expected exception so it is not propagated further.
    // Perhaps write this exception out to log file for gathering statistics...
}
catch (Exception)
{
    // An unexpected exception that we don't know how to handle.
    // Perhaps write this exception out to log file for support purposes...
    throw;
}
finally
{
    // This will:
    // - be executed if any exception was thrown above in the 'try' (including ThreadAbortException); and
    // - ensure that CloseOrAbortServiceChannel() itself will not be interrupted by a ThreadAbortException
    //   (since it is executing from within a 'finally' block)
    CloseOrAbortServiceChannel(client);

    // Unreference the client
    client = null;
}



private void CloseOrAbortServiceChannel(ICommunicationObject communicationObject)
{
    bool isClosed = false;

    if (communicationObject == null || communicationObject.State == CommunicationState.Closed)
    {
        return;
    }

    try 
    {
        if (communicationObject.State != CommunicationState.Faulted)
        {
            communicationObject.Close();
            isClosed = true;
        }
    }
    catch (CommunicationException)
    {
        // Catch this expected exception so it is not propagated further.
        // Perhaps write this exception out to log file for gathering statistics...
    }
    catch (TimeoutException)
    {
        // Catch this expected exception so it is not propagated further.
        // Perhaps write this exception out to log file for gathering statistics...
    }
    catch (Exception)
    {
        // An unexpected exception that we don't know how to handle.
        // Perhaps write this exception out to log file for support purposes...
        throw;
    }
    finally
    {
        // If State was Faulted or any exception occurred while doing the Close(), then do an Abort()
        if (!isClosed)
        {
            AbortServiceChannel(communicationObject);
        }
    }
}

private static void AbortServiceChannel(ICommunicationObject communicationObject)
{
    try
    {
        communicationObject.Abort();
    }
    catch (Exception)
    {
        // An unexpected exception that we don't know how to handle.
        // If we are in this situation:
        // - we should NOT retry the Abort() because it has already failed and there is nothing to suggest it could be successful next time
        // - the abort may have partially succeeded
        // - the actual service call may have been successful
        //
        // The only thing we can do is hope that the channel's resources have been released.
        // Do not rethrow this exception because the actual service operation call might have succeeded
        // and an exception closing the channel should not stop the client doing whatever it does next.
        //
        // Perhaps write this exception out to log file for gathering statistics and support purposes...
    }
}

Well, that's quite depressing, isn't it! Imagine that you have an application that calls many services. If you were to tell me that I should duplicate all that code every time I want to make a service operation call, as a developer I won't be happy.

Unfortunately that is exactly the situation that Microsoft has forced upon developers.

You could take some short-cuts and not do all the exception handling, but no doubt on the day that one of those perhaps rare exceptions happen (and it will!), you will be glad that you handled those edge cases.

Please Tell Me There Is a Better Way!

In my next article, I will show you how to use some programming tricks to significantly reduce the amount of code that developers have to write and provide a nice, clean API for working with WCF clients.

Thoughts on the Naming of SOA Services and Operations

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Recently I was having some discussions on the naming of Service-Oriented Architecture (SOA) services and their operations. There were some differing opinions on the length of the names and concerns about the duplication of some words in both the service name and operation names.

Naming Principles

As a general set of principles, I prefer to use names that are: intuitive, understandable, more readable in typical English, discoverable and allow for extensibility.

Microsoft has some useful naming conventions and guidelines for .NET that are reasonably mature and generally can be applied to SOA service names.

Service Names

As an example, let us assume that in a domain we have products/stock/inventory that is acquired and sold. We could say that there should be a service for the management of inventory items.

We therefore could propose an "Inventory Management" service to record the addition and removal of stock. A valid alternative name also could be "Inventory" service. "Inventory" as a service name obviously is shorter than "Inventory Management". So is that better?

One could at this point perhaps flip a coin and naively settle on either option. But I wouldn't recommend that...

Do those service names comply with the above-stated principles? Maybe - it depends on the domain.

Let me now give you some more possible information about the domain. When inventory is sold or moved to another department, there are typically corresponding accounting entries that need to be recorded. We therefore could propose an "Inventory Movement" service to encapsulate this.

So now in this domain, we optionally could have the following:

  1. "Inventory" and "Inventory Movement" services, or
  2. "Inventory Management" and "Inventory Movement" services.

For me, seeing the juxtaposition of both service names in option (1) makes me feel uneasy, highlights ambiguity and causes me confusion. Since there is "Inventory Movement", what is the role of "Inventory"?

Additionally, "Inventory" sounds very much like a data entity that one might perform CRUD operations on - as opposed to a Business Service.

Option (2) however is more intuitive, less ambiguous and causes me less confusion. "Inventory Management" intuitively sounds like it could be related to the management of inventory items (whatever that may be...). Overall for me, this makes more common sense than option (1).

So now, if you agree, we can see that the more specific service name of "Inventory Management" (even though it is longer and slightly more annoying to repeatedly type) better allows for business changes within a domain. In other words, more specific service names allow for future extensibility of the domain with less ambiguity. Having said this, we do need to remain vigilant and be careful that we are not overtly specific with our service names such that we make our services to narrowly focused...

Ok, let's now look at the operation names.

Operation Names

As an example, let us assume that we have an "Order Management" service. In this service we need to have operations for adding new orders to the system. We might therefore have an operation named "Add Order". Alternatively, we could have an operation just named "Add". "Add" is obviously shorter than "Add Order", and does not repeat the word "Order" - which you know from the service name. So is that better?

One could at this point perhaps flip a coin and naively settle on either option. But I wouldn't recommend that...

Do those operation names comply with the above-stated principles? Maybe - it depends on the service.

Let me now give you some more possible information about the service. Existing orders may need to be adjusted. In fact, there might be a need to add new order items to an existing order. We therefore could propose another operation named "Add Order Item" or "Add Item".

So now in this service, we optionally could have the following:

  1. "Add" and "Add Item" operations, or
  2. "Add Order" and "Add Order Item" operations.

Again, for me, seeing the juxtaposition of both operations names in option (1) makes me feel uneasy, highlights ambiguity and causes me confusion. Since there is "Add Item", what does the operation "Add" actually add?

Option (2) however is more intuitive, less ambiguous and causes me less confusion. Overall for me, this makes more common sense than option (1), and provides extensibility to allow for other operations in the future with less ambiguity.

Summary

I recommend erring on the safe side and selecting names that remain intuitive when taken out of the context of its grouping/category, and be carefully explicit with names - because you don't know how the business is going to change and how that could affect the domain. This is especially true if your team is operating in an agile fashion and developing and evolving the services and operations as you go.

The length of names and duplication of words in operation and service names should be less of a concern than using names that are intuitive and allow for change with less ambiguity. If you are not explicit enough, then you increase the risk of future services or operations making your existing names ambiguous. Alternatively, if you are too explicit, you could narrow the scope too much and reduce extensibility in other ways.

A Comparison of Website Hosting Solutions

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When I recently started building ChannelAdam and this Software Development Zone, I considered many different types of website technologies including various blog engines, content management systems and programming languages.

However, I couldn't decide which technology I should use until I had a better idea of how I would host the sites. As a polyglot programmer, the language and technology was the least of my concerns. I had 4 overarching principles that would guide the hosting and development of this site.

My Principles / Technology Selection Criteria

The principles I wanted to follow, and thus the selection criteria for hosting were:

  1. Low cost. Since this is a hobby, I want to keep the cost of hosting this operation very low or even better, free.
  2. Branding. I must have a custom domain.
  3. Trustworthiness and security. I must have SSL. I consider it to be my duty to you, in good conscience. When you visit my website, I want you to be assured that the content you see was not tampered with between my server and your browser (i.e. no Man-in-the-Middle attacks - especially with so many public, unsecured Wi-Fi access points these days. For this reason, I agree with the SSL/HTTPS Everywhere movement, and I think that all websites should be HTTPS, even if they don't specifically have any sensitive content. Let's keep the web safer!
  4. Search Engine Optimisation. I must have SEO and page redirection capability for changing the structure of the site in the future.
  5. Stability, scalability and availability. The host must be stable and have high availability.

Tell Me the Results Already!

After researching the various hosts and platform providers, I was a little disappointed. Hosting a website, with a custom domain and SSL is not commonly done cheaply.

Having said that, RedHat OpenShift won outright - they are the ONLY host offering free hosting, with a custom domain and SSL, and scaling up to 3 'gears' for free. In order to get the SSL however, you apparently need to register and upgrade to the zero dollar Bronze plan and enter your credit card details. The only problem is that they do not yet accept billing addresses for people in Australia - so sadly I cannot yet use OpenShift.

The next best host I found, after some positive word of mouth, was Digital Ocean. $5 a month for a Linux box under my complete control, with a custom domain and SSL.

At the moment, Digital Ocean has my business...

The Long Version of the Results

The Plan to Reduce Costs

I quickly determined that the easiest way to reduce costs is to have a static website only. This reduces cost because the size of the server can remain small and still perform under high load.

In addition, it is possible to use Content Delivery Networks (CDNs) to serve your static files. The problem with CDNs however, is that the free ones I found do not support SSL.

After researching the current state of Static Site Generators (SSGs), I was sufficiently convinced that I could develop the majority of Channel Adam as a static website with the help of a SSG.

The cost of SSL certificates was mitigated with StartSSL - where anyone can get a free SSL certificate (for their non-commercial website).

The Comparison

Below are some of the hosts that I researched. Not every cell in the table is filled out, either because the host does not offer the service or I quickly lost interest in them due to other criteria not being met...

Host Free Tier Expansion Technologies Custom Domain Support SSL Support Redirects
Heroku 1x Dyno (512 mb RAM, 1x CPU Share)

Dev/Hobby Postgres Database with up to 10k rows (and up to 4 hours downtime per month)

Standard support 1+ Day response times
2x Dynos (512 mb RAM, 1x CPU Share)

$0.05c/dyno-hour ($34.50/month)

Basic 10M rows $9/month

Premium Support 24/7, 1-hour response SLA, $1000/month
Node.js, Java, Ruby, Python

See Heroko Addons
Free

See Custom Domains
$20/month for a SSL Endpoint

Available in US and Europe regions

See: SSL Endpoint
SSL
dotCloud None Static site, 1 instance, 32mb RAM

$0.06/hour ($4.32/month)

Postgres $8.64/month
PHP, Node.js, Python, Ruby, Perl, ... Yes, unlimited SSL Load Balancer $21.60/month

See: SSL
AppFog None Basic $20/month

Unlimited apps within 2GB RAM. Up to 8 service instances.

200mb storage per MySQL or Postgres instance

10GB total data transfer

40 requests per second per app instance
Java, Node.js, Ruby, Python, PHP Unlimited 2 dedicated SSL endpoints (on AWS) for the Developer $50/month plan or better.
Amazon S3 1 year only Free Usage Tier.

5 GB of Amazon S3 standard storage, 20000 Get Requests, 2000 Put Requests, and 15GB of data transfer out each month.
First 1 TB / month $0.0330/GB, plus data transfer fees. Files

See:
Website Hosting

Gotcha using virtual host

How to server S3 over https with CloudFront
Yes - Amazon S3 with Amazon Route 53 DNS

Custom domain walkthrough

Custom SSL domain names
Yes - with Amazon CloudFront

Custom SSL

SNI Custom SSL - no upfront or monthly fees for certificate management; simply pay normal Amazon CloudFront rates for data transfer and HTTPS requests.
e.g. $0.0125 per 10K HTTPS requests plus data transfer of $0.190 for the first 10TB per month.

Dedicated-IP - $600 for each custom SSL certificate you associate with your CloudFront distributions, pro-rated by the hour.

How to serve S3 over https with CloudFront
Gondor None Shared Hosting. A slot is 1 Python WSGI process or 2.5 GB PostgreSQL database or 64 MB Redis cache or 1 Celery process
$10/month
Python Yes Yes. Dedicated-IP SSL
OpenShift 1-3 Gears

Custom domain

Shared SSL certificate for rhcloud.com

SNI SSL for custom domain

512mb RAM

1GB storage per gear

As an example, this is suitable for a Drupal-based app with:
15 pages/second
Hundreds of articles
~50k visitors per month
Small gears

$0.02/hour

Medium gear

$0.05/hour

(recommended for Java)
PHP, Perl, Python, Ruby, Node.js, Java Yes for $0/month Yes for $0/month Yes, depending on the technology used.
Google App Engine 28 instance hours
5GB cloud storage
1GB/app per day incoming data
1GB/app per day outgoing data
See: Quotas
Static resources are placed in the cache and are therefore not part of instance hours
$0.05 / instance / hour
Cloud storage $0.026 / GB / month
Incoming data free
Outgoing data $0.12 / GB
See: App Engine
Python, Java, PHP, Go

See:
Static files in Python

Host on Google Server

Implementing a static website in Google App Engine

Git push to deploy
Yes.

Domain
SNI SSL certificate slots are offered for no additional charge for accounts that have billing activated.

See:
Pricing
SSL

Virtual IP - $39/month
NOT FOR STATIC CONTENT
Google Compute Engine 1 core, 3.75 GB RAM, $0.07/hour Node.js
Microsoft Azure Websites Up to 10 free websites, 1GB storage, *.azurewebsites.net subdomain and SSL Shared preview price: $0.013/hour (~$10/month)

Basic Plan: Small instance, 1 CPU core, 1.75MB RAM, $0.075/hour, (~$56/month)

Standard Plan: Small instance, $0.10/hour, (~75/month)
.NET, PHP, Node.js, Python, Java Not on Free plan. On Shared plan and above. Not on Free or Shared plans.

On Basic plan: SNI SSL $9/month, IP SSL $39/month

On Standard plan: 5 SNI SSL and 1 IP SSL included.
Microsoft Azure CDN

Storage block blob with a CDN endpoint and custom domain
Locally redundant storage: $0.069 per GB for the first TB
Geo Redundant, Read Only Geo Redundant

$0.005 per 100,000 transactions across all Storage types

See: Pricing
See:
How to use CDN

How to enable CDN

How to map CDN content to a custom domain

Configure custom domain name in Azure Storage
Yes Yes, but NOT on custom domain.

See: SSL cert for custom domain endpoint on CDN
GitHub Pages 1GB per repository, 100mb per file Html, Markdown, Jekyll

See: Using Jekyll
Yes

See: My custom domain isn't working
No
BitBucket

Static website hosting
Digital Ocean None 512mb RAM, 1 Core processor, 20GB SSD Disk, 1TB Transfer, $0.015/hour ($5 / month)
Websites hosted on Google Drive
Modulus.io $0.02/hour, 296MB RAM + 512MB Swap

Conclusion

It is possible to run a website cheaply, with a custom domain and a free SSL certificate - you just have to do the research in order to find the best deal.

For me, RedHat OpenShift and Digital Ocean are leaders in their field.

Coming Soon!

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ChannelAdam and this Software Development Zone have just been reconstructed. As is typically the case, there is still more work required that is related to the reconstruction...

Once all that has been completed though, I will be writing quite a few articles I already have queued up - so watch this space!