PayPal IPN – Creating Listener Code to Process IPN Messages

You have finally decided IPN is the solution to your website application. You do not want to pay someone else to do it. It can not be that hard, can it? Where can you get some practical advice from people who have been there, done that. This article will answer these questions and help you decide if you are able to write that code. If you find it too complicated there are a few commercial products out there that will handle everything for you so do not lose heart if you find yourself stuck.

PayPal IPN

Instant Payment Notification is better known as PayPal IPN and is PayPal's interface for handling real time confirmation of purchases. A typical use for IPN is where you want to use the software to download.

PayPal provide 3 different types of account. Personal, Premier and Business. You will need Premier or Business to use IPN.

Listener

PayPal IPN messages are not synchronized with actions on your website. You detect IPN messages from PayPal with a piece of code known as a listener.

You specify the URL of your listener in your PayPal account's profile but you can override this for specific transactions when you setup a button or API operation. You can also temporarily turn off the sending of IPN messages, useful if your site is down for maintenance. They are still generated and stored until you switch sending back on again.

You must perform a number of checks on the IPN message received from PayPal.

  • Check the email address to make sure it is yours
  • Check that you have not already processed the transaction identified by the transaction ID
  • Make sure that the transaction's payment status is "completed"
  • Verify that the payment amount actually matches what you intend to charge

PayPal Sandbox

When you are developing your website you really do not want to be trying to get it working by experimenting on a real money system. Any early bugs in the system could leave security holes but even if you write perfect code it is best not to do your testing using real money.

PayPal provides what they call a sandbox, almost identical to the live PayPal system. You can setup fake customers with fake money and make as many test purchases as you want. The perfect system to fully test your web application.

There is a Sandbox Forum on the developer network. It's a great place for advice.

Testing your Listener

The Sandbox has an excellent IPN Simulator (under Test Tools) which lets you choose the transaction type, fill in all the parameter values ​​and send a test IPN to a specified address.

IPN History

PayPal provides an IPN history page under the My Account tab. Click on History to see it. It includes everything you want to know about each IPN message including the following Status values.

  • Sent: indicates that PayPal sent the message to your IPN listener
  • Failed: indicates that PayPal did not receive an acknowledgment to the message
  • Queued: indicates that PayPal is ready to send the message
  • Retrying: indicates that message was resent between 1 and 15 times and PayPal continues to be resend the message
  • Disabled: indicating that the message will not be resent because the merchant's account has been disabled

Conclusion

The best place to search for information is the PayPal Integration Center which has guides, code and links for everything to do with integrating your website with PayPal.

The one place you MUST visit is the PayPal IPN Forum on the developer website. As well as a constantly changing list of discussion topics about IPN, there are some good sticky posts about troubleshooting tips, IPN variables, template code etc.

PayPal IPN is a difficult subject but the combination of an excellent testing environment in the form of the sandbox and the good quality advice provided through the forums should make it possible for you to get your website application up and running.

Answers To 7 Popular Search Engine Optimization Questions

More and more website owners realize the benefits of top search engine ranking. Therefore, they are willing to invest their time and money in search engine optimization. At the same time, many search engine optimization problems arise. I am trying to address some of them in this article.

Question 1. For the sake of time saving, I just scan our pamphlet as an image file and put it on our main site. Can you help me optimize the website for high ranking?

Your pamphlet may contain lots of text for visitors to read. Since you only scan it as an image file, search engines only recognize that you have a single image file in your webpage. Simply put, they just treat it like a photo or a graphic, and do not convert your image text for analysis and indexing. A solution is to add an alt attribute for the image. It is a bit better because a few HTML text are available for search engines to "understand" your webpage content. However, comparing with rich HTML text in a webpage, text in alt attribute is too few for search engines to analyze significance of your webpage.

Therefore, I do not recommend this approach although it may save you time in building a webpage.

Question 2. If I implement a SEO campaign, does it mean that I can give up my pay per click search engines marketing (PPC marketing)?

SEO campaign and PPC marketing are not mutually exclusive. On the contradiction, they are complementary with each other. First, I suggest you implement both natural SEO and PPC marketing for high conversion keywords. You can get more exposure in the search result pages. Second, because of copywriting or marketing communications consideration, you may not be able to implement SEO for all useful keywords. Under this circumstance, why not use PPC marketing as an alternative? For example, the word "pay-per-click search marketing", "PPC marketing", "search engine marketing", "paid search" are more or less with the same meaning. However, it may be confusing to use all the terms interchangeably through your website.

Question 3. My boss wants to have a full flash website so that our company site is more visually appealing. Can you help me to optimize the website after we make a full flash website?

From experience, many search engines can not "read" content from flash files. In many cases, search engines only treat flash file as if it is a single image file. They do not index the text or follow the navigation links to index content.

Matt Cutts, a Google representative, stated that Google has some improvements in reading textual content of a flash file by utilizing the search engine SDK tool offered by Adobe / Macromedia. However, the tool has not been updated frequently and extract text out of a flash file correctly is difficult. To conclude, reading textual content from flash file is still at a preliminary stage.

It implies that a full flash website is unlicensed to be well indexed by search engines. If natural top search engine ranking is very important to your success, it is not recommended to make a full flash website unless you have a large PPC marketing budget or very confident to create high link popularity over short period of time.

Question 4. Does a dedicated IP address help my search engine rankings?

Dedicated IP address is not an imperative to get top search engine ranking. Many websites with top search engine ranking are using shared web hosting plans. It means that they are sharing the same IP address with other webmasters with low search engine ranking.

However, if your IP address is shared with many search engine spammers, your site's ranking can be adversely affected. Therefore, some search engine marketers prefer to get a dedicated IP address from their web hosts.

Question 5. If I have lots of content in a webpage, is it better to separate the content into 2 webpages?

I think it depends on search engines. For example, Google crawls only about the first 101 kilobytes of a webpage. If your content is more than 101Kb, you're better separating the content into 2 webpages.

Question 6. Why does my site suddenly disappear in Google?

There are several reasons for Google to exclude your site. First, you must make sure that your site meets Google's quality guideline, ie no spamming. For example, you do not put hidden text and links in your website. Second, your site is not hacked. Third, you should check whether your site has some malware. Last but not least, your site may be too new and Google is in the process of refreshing their index. During the process, Google may fall back to the old index version and hence your site suddenly disappears.

Question 7. How can I increase ranking of internal sub-pages?

Many webmasters found that sub-pages of their sites have poor search engine ranking and want to improve rankings of sub-pages. To solve the problem, you should ensure the sub-pages are not buried too deep within a site. Important sub-pages should get more internal links via cross linking related pages. In addition, you should try to get some external site links to your specific sub-pages.

Oh My – Traveling the Yellow Brick Road to Employment

This week I posted a researcher / admin job on Craigslist. Within 90 minutes I had 75 resumes. Here are 14 things that came to mind when reviewing responses to my listing:

  1. Put your employment objectives at the top of your resume but make them about serving your employer not about YOU. Employment is not about you, it's about an agreement to deliver services for $$.
  2. It's not a good idea to have typos in a resume. I rejected those immediately.
  3. Write in complete sentences and check your grammar and punctuation.
  4. Put a greeting with some info into the email. With 75 resumes there was no way in heck I was going to read a resume without an introduction.
  5. Remember to attach the resume.
  6. At least try to match your qualifications with the job description. Please.
  7. Do not write about your interest in learning to do the job. I need an assistant not an intern.
  8. Do not suggest you would love to work in my organization and know all about it because, you do not: It's Craig's List, I'm under cover!
  9. Include references.
  10. If you have a new job every three months, explain yourself.
  11. Respond early. I opened the emails in chronological order and some early responders where eminently qualified.
  12. Do not send a sexy seductive picture (yep, someone did that).
  13. Do not make me guess your abilities. There's too much competition. You have to make me want to hire you based on your qualifications.

It's tough to make the transition from one field of work to another (eg, retail to administration). Think about how your old / current job keep you the right skills for you new job and explain it in a cover letter. Be creative yet honest.

Antique Furniture: The Timeless Classic

When you do a search online for Antique Furniture, one of the first listings that pop up is a Wikipedia article stating just the general basics of how antique furniture is valued. These criteria include how the monetary value of a piece of antique furniture correlates to its age, rarity, and condition.

What exactly does this mean for a consumer looking to add antique decor to a house? The factors vary. While they are highly collectible, acquiring Antique Furniture began as a means to express one's status, and to this day is still an effective means to do so. Antique Furniture captures the essence of the height of style and luxury from the era the furniture originates. Purchasing a table from Leighton Hall for example, captures the grandeur of the old English estate, and can create a similar feeling of ageless rustic royalty in the room. Alternately, a purchase of antique EJ Victor furniture may create the appearance eighth century high class with its hand made craftsmanship.

These days, most furniture stores will offer to sell antiques right along their brand new factory-direct couches, tables, chairs and cabinets. In these situations, caveat emptor is the rule. Without you already happen to be a connoisseur of all things antique, or can bring one with you, it is recommended that you keep your eye open for a couple of things. If you want a real antique, see if you can find some sort of maker's mark. Once locating this, take note of a manufacture date. Take this information to a knowledgeable source to see if they have any more information for you concerning the piece of furniture you have your eye on. Something you can do on your own is to look for imperfections in the restoration of the article you are thinking about purchasing. Uneven finishes, mottle veneer, and other indicators that it was a rushed job are all signs that you should either move on, or expect to spend some extra money fixing it up.

Those looking specifically for Antique Furniture will have much better luck going to an actual antiques furniture store. Many of them have a passion for the business, and these individuals are knowledgeable about their work. Instead of going off site for information about an item of furniture you have in mind, sales staff often times have great insight into the items they sell. You also will be hard pressed to find a better selection of antique furniture than at a store that actually specializes in what you're looking for. At a good antique store you'll be able to find a wide assortment of price, style, and rarity while being met with excellent condition across the board.