Archive for the ‘Solr’ Category

Search System Audit

by Karen Lynn

Selecting a search platform is a big decision. You may already have a solution in place that is ineffective and you need a change. But what’s not working, and why? Which search engine is best for my needs? We perform an audit and full evaluation of your current search architecture and report our recommendations for optimizing what you already have, and list attributes of alternative technologies like Solr, LucidWorks Enterprise, ElasticSearch, SearchBlox or other solutions. Our full evaluation includes:

  1. Audit of existing enterprise search solution and evaluation of available options for improvement.
  2. Report on current performance, areas of targeted improvement, and recommendations
  3. Migration Plan. At the conclusion of the audit engagement, we provide a step by step plan on what needs to be done to migrate to a search solutions that supports your business goals and needs

Our audits are conducted by one of our senior software developers and takes place over a 3 day period. We will interviewing relevant staff members to gain valuable insights to pain points on performance. Our developer will access your back-end systems and review the following areas:

  • Review all source code, if available and applicable
  • Crawling web resources: pages and documents, forums, blogs Content processing and conversion
  • Content enhancement and extraction
  • PDF search by page
  • Search and database integration architecture design, scaling, performance, tuning, hardware requirements, and related expertise
  • Related searches, database indexing, vertical search engines, custom scoring/ranking, etc.
  • Performance troubleshooting (slow queries, high memory usage)
  • Database and file-system indexing, web crawling and searching
  • Document parsing and information extraction
  • Large-scale indexing and searching, distributed search
  • Crawling web resources: CMS based sites, blogs, forums, static html, PDFs, docs
  • Content processing and conversion
  • Content enhancement and extraction
  • PDF search results by page, mutli-page indexing, and multi-page image caching
  • Search and database integration

After this extensive review, we can better advise on which search platform to move your systems. Your business needs are weighed heavily in this evaluation, because after all, your search system is a core technology that enables knowledge management and data extraction for business decision making. We conduct search architecture audits for web portals, online directories, online databases, for the enterprise, and for virtually any web based application. Audits are the first step in making the right decision about a search platform. For more information on how a search audit can assist you in making a smarter technology decision for your organization, contact us.

Migration from FAST to Solr White Paper to be Released

by Karen Lynn

TNR Global plans to release a White Paper on FAST to Solr Migration by the end of this week on Friday the 13th, 2012 Wednesday, January 18, 2012. The paper will build upon Michael McIntosh’s presentation at Apache Lucene EuroCon.  Newer information will be included including different tools used for implementation.

The paper will be free and available to those who sign up here.

With the dwindling support for FAST customers on a Linux operating system, TNR believes that migrating off FAST ESP to another search engine like Lucene Solr will be mission critical for many companies over the next few years.  TNR has worked with the FAST search engine for many years now and understands the qualities that many companies have grown to love and depend upon for the search needs.  We have turned to Solr to take the best features of FAST and enhance it with some of Solr’s own strengths.  It is a highly reliable, scalable, lightweight technology with fast searching and indexing speeds. Solr has powerful result relevance and ranking, faceting.  And because Solr is open source, it’s a lot easier to make adjustments to the engine–something that was always a challenge with any proprietary search engine–including FAST.

Contact us if you want to talk to us about how we can help your team migrate off FAST to Solr or another search engine.  We’re happy to assist with a short consultation, a partial, or a full implementation.

FAST ESP to Lucene Solr Presentation: Open Call for Questions

by Karen Lynn

TNR Global is excited to be participating in the Apache Lucene EuroCon conference in Barcelona.  Our own Michael McIntosh is scheduled to present:  “Enterprise Search: FAST ESP to Lucene Solr” Here is your chance to pre-load the discussion. Before Michael puts the final touches on his talk, he wants to know what issues or questions you may be have.  In the following video, he touches on some of the highlights of his upcoming talk, and asks for your input.

Enterprise Search: FAST ESP to Lucene Solr pre-conferece video - Click to Watch

Enterprise Search: FAST ESP to Lucene Solr pre-conf video

To participate in advance, send you questions or comments to:  fast2solr@tnrglobal.com.  While Michael cannot promise he will include your question or commentary in his actual talk, he will work to address them in an upcoming White Paper, to be released after the conference in November 2011. We look forward to hearing from you!

Crawling Solr

by Karen Lynn

Recently there has been a lively discussion on Linked In’s Enterprise Search Engine Professionals Group started with this question:


“Is it an handicap for Solr to depend on third party solutions for crawling the Web like Nutch?


Our own Michael McIntosh felt compelled to respond. What follows is his post to this topic in it’s entirety.


“This topic makes me think of the saying “Write programs that do one thing and do it well.” The longer version of this philosophy, as expressed by Doug McIlroy, is this: “Write programs that do one thing and do it well. Write programs to work together. Write programs to handle text streams, because that is a universal interface.” Solr stands very well on its own and, based upon my impression of the Solr community so far, more people currently use Solr for structured content vs unstructured like web documents. I think that Solr should have some ‘out of the box’ web crawler implementation available, but it should not be the core focus. It can serve to allow new users of Solr to focus more on the Solr/Lucene side of things and not have to worry about rolling their own crawler or figuring out which is the best third-party crawling solution to use. I suspect that many people who need to do crawling can get by with a fairly basic crawler. My impression of Nutch so far is that is more complicated than most Solr users need out of the starting gate. That said, if you have a business that deals with large amounts of crawled unstructured content, its very likely they will need something more robust than you can reasonably ship & support as part of the Solr project. For one of our clients, the size of our dataset has grown from needed just a couple boxes, to multiple clusters with many machines each. One of the newest developments is the growth of the amount of unstructured content has grown to a size where we now need a crawler CLUSTER. When we first started on this, it never occurred to us that we might need multiple machines for the crawling side of the equation, but it has happened. But I think our case its less common. All in all, I think Solr should have a bare-bones reference implementation of a crawler that can easily be expanded upon, but it is probably not an effective use of effort to Solr developers to focus on the crawling side. Let a third party focus on the issues of crawling, it is a deceptively complicated issue.”


After his post I caught him in the office and asked where he was going with this line of thinking. “We are looking at creating a suitable enterprise crawler to replace the one provided by ESP to support customers doing a ESP to Solr migration.” He revealed. Sounds like a very promising solution to a fairly big, and common problem for companies with vast amounts of metadata. And as for unstructured content? Well, it’s the proverbial elephant in the room, don’t you think?


To see the entire conversation, with contributions from experts in the field of search architecture, click here. To get in touch with Michael directly to discuss your architecture and crawling needs, contact us.

Migration Still Looms Large on the Horizon for FAST ESP Customers

by Karen Lynn

Microsoft acquired FAST all the way back in 2008 and then in early 2010 disclosed it’s plans to stop updating the FAST product on a Linux operating system after 2010, making FAST ESP 5.3 the latest and greatest, and very last update Linux users will see involving any improvements to the proprietary search platform. It was clear to anyone on Linux that a migration would need to occur, and as content grows, depending upon the size of your organization, that migration should probably happen sooner than later.

Buzz about migration ensued–an inevitable certainty for many companies, especially ones with huge amounts of data. But how many companies have jumped in with both feet? I had the opportunity to speak with an open source search engine expert who, along with the industry, believed that the move from Microsoft was a windfall for anyone in the business of enterprise search design and implementation. However, she admitted “we haven’t seen as large a response as we expected.”

This isn’t exactly surprising to everyone. “It’s coming” says our VP of Search Technologies, Michael McIntosh. “Corporations have an enormous investment in FAST ESP and it makes sense that they would be reluctant to move to something new until they absolutely have to.” That means, when their licenses expire.

“They will likely weigh the performance and support, or lack thereof, for the FAST ESP technical team with the timing of renewing a license and wait until they absolutely have to change to something else,” says McIntosh.

The purchase of Autonomy and the shift of HP from hardware to software could signal a recognition from Goliath HP the kind of growth opportunity enterprise search software offers, and that the “great shift” from FAST ESP to another search platform is very much on the horizon.

But as the clock continues to tick, companies using FAST ESP should be strategizing for migration now. “It’s an enormous undertaking to migrate an entire search solution from FAST to another platform. Designing a non-trivial search solution to fully meet your needs from scratch is hard enough on its own. If you are migrating an existing solution, it is very unlikely that you will find a one to one mapping of all of the features in a new search engine that you have come to depend upon with your existing implementation. Solving challenging issues like that requires both creativity and expertise to address your needs.” says McIntosh. If a need for migration is eminent, there will be a real need for expertise in the field of enterprise search on both proprietary and open source platforms, depending upon several factors like size, in house talent, and growth expectations.

How is your company preparing for the discontinuation of support of FAST ESP?  Need guidance?  Contact us for pointers, analysis, or architecture for a full migration.

Open Source Search Engines vs. Proprietary Search Engines

by Karen Lynn

There are plenty of articles about the pros and cons of open source software vs. proprietary software. I sat down with our VP of Search Technologies Michael McIntosh to discuss the benefits of each in terms of search engines.

Karen: You’ve been working with proprietary search engines for some time now. Tell me your thoughts on that. What’s the upside of proprietary?

Michael: I’ve worked with proprietary search engines for several years, specifically with FAST ESP since 2003 back when it was known as FAST Data Search (FDS). Proprietary software products often have better documentation, better support; more thought out design and are more aggressively tested. Because the product supports an entire company—it must succeed. They have nicer tools, nicer interfaces.

Karen: And the downsides?

Michael: “Over the years, we’ve run into a number of difficulties with proprietary search engines. One thing that comes up is that if a problem isn’t outlined in user troubleshooting documentation, it can become incredibly difficult to diagnosis and correct, and doing that is a frustrating, time intensive problem. The black box nature of the product is very limiting. If it’s not in documentation, it might as well not exist at all.”

Karen: There are gaps in the user manual?

Michael: “Yes. But in defense of FAST ESP, the documentation has improved by leaps and bounds over the years. However, one anomaly we find is that the clean, easy to read PDF form of user documentation (the original) for ESP is often not as up-to-date or helpful as the searchable online documentation—which is harder to read, but usually more current and correct. Sometimes even the online documentation is wrong—which is also frustrating. But it has become something we cope with regard to FAST”

Karen: Give me an example of what kind of problems you run into when integrating the proprietary search engine into a client’s website.

Michael: “The enterprise search platform uses Service Oriented Architecture (SOA). That is a bunch of different components that are able communicate with each other as services. With this type of architecture, it doesn’t matter which language you write something in as long as it’s a service another language can communicate with via RESTful interfaces, SOAP or something like XML-RPC. These services can all work together, despite the fact you don’t have a unified api—and that’s actually awesome.

Karen: Why?

Michael: “Indexers for one—you generally don’t want them written in an interpreted language for performance reasons. Indexing can be a CPU intensive operation, which can be a weak spot for interpreted languages such as Python or Ruby compared to languages like C/C++ or Java. It is both CPU and disk intensive process so a scripting language can be great if you’re writing an application that’s not CPU intensive because code speed doesn’t matter so much. The true slow-down is something outside the script. You can optimize the speed of the script to make it run as fast as humanly possible but you’re limited because the disk can only rotate so fast. Your indexing service can be written in a low level language like C vs. some of the other services in languages like Python or Ruby or Java and get good performance. BUT if you don’t have documentation for compiled programs that make up the search engine product you’re going to have a terrible time trying to figure out how to fix issues when they arise.

Karen: “So basically, because you have so many different languages being used that you lack the source code for, and documentation is spotty, it becomes a needle in a haystack trying to figure out where the problem occurs.”

Michael: “Yes. And this is not such a problem for anyone using a search engine for really basic applications. The place where you run into problems is if you push the search engine technology to its limits or you are using it in ways outside its typical usage, which is almost everything we do. We are always trying to get the best possible performance out of the search engine. We’re trying to get the search engine to deal with features we need but it doesn’t natively support.

Karen: “What is it you’re pushing specifically for the search engine to do?”

Michael: “One thing we want is for FAST ESP to have is a feature to deal with creating a faceted search for arbitrary fields. The way ESP works is that it has an index profile which is a statically defined set of fields that it indexes. Inside its index profile you can mark certain fields to have navigators. One of our customers deals with product verticals. They have a whole bunch of products that aren’t unified—all with completely different attributes. We’ve managed to work around these roadblocks in ESP to create faceted navigation on arbitrary fields.

Karen: “So you get creative to make it better.”

Michael: “Yes we constantly get creative to make it better to use its strengths and find ways to work around its limitations.”

“Another issue we have with ESP is we have a number of websites we need crawled and each website has metadata associated with it. Unfortunately the way the ESP crawler works, there are not many straightforward ways to preserve metadata associated with the seed URL which we use to crawl a website and pass the meta information along to any associated links. We can’t do this easily inside the ESP crawler. Since its proprietary and black box, we can’t look at the source code to the crawler, and can’t modify the source code to the crawler. When it does something mysterious, we can have no idea why it might be behaving in an unwanted way. We had one instance when we had a number of websites the crawler was temporarily blacklisting for some reason. When the ESP crawler automatically blacklists a site, it stops crawling the site for 30 minutes and then begins again after 30 minutes. We learned one thing that triggers blacklisting is if a website has HTTP 503 errors. If a site has more than 20 or so of those errors, the crawler temporarily blacklists the site. The problem was that the documentation is too sparse on details for that topic. When we ran into that problem—it was really difficult to know what was going on so we could properly explain the issue to the client and address the problem. Conversely, if we had an open source search engine, I could have just searched the source code and speed up the diagnosis of the problem.”

Karen: So from a business prospective—using open source allows you to invest in a technology that gives you the power to modify the code to better meet your business needs.

Michael: “It certainly can. It can accelerate development time and speed of diagnosing problems when issues pop up. And issues always do pop up. If something is not working very well, we can look at the problem which a much higher degree of granularity.

If it’s a simple problem, we never contact support. We only contact support when we’re stumped. And we’re not easily stumped. Usually, they can’t answer they question immediately because if we’re asking for help, the problem is complex. Our ticket is escalated, and eventually we talk to someone who can help us. But it does take time. Even if a support staff is top notch, there is the time is costs to deal with that, and that costs us and our clients’ time. We have a highly customized ESP installation for one of our clients it always take an enormous amount of time to explain over and over how we have our systems set up, the different parts work, and it’s a big pain to go through that every time I run across a problem. If it were open source, I can simply look at the source code and solve the problem.”

Karen: Let’s talk in more detail about open source search engines. Upsides?

Michael: “If you choose a popular open source search engine solution like Lucene Solr, you have an active, passionate community behind that solution. There are several developers looking at that engine, working on it, and actively posting in publicly available forums. You can often get your questions answered there by top notch experts in search technology. You can potentially talk to the original coders and creators of the product—and they are often happy to help you. I’ve seen people post a Solr question on their twitter feed and within 7 seconds, the creator has responded with a link to a forum explaining the solution.

Karen: Wow, that’s amazing. Other advantages?

Michael: “It’s free. That’s attractive to most companies. The downside is the formal documentation isn’t usually as good as the proprietary, and there isn’t a dedicated support team for the product. But if you have some savvy software developers on your team, the open source community is robust and willing to share information about the product. And having access to the source code is extremely valuable.”

Karen: So in your opinion, what’s the bottom line on Open Source Search Engines vs. Proprietary Search Engines?

Michael: “If you are a cutting edge company, you will be severely limited by a proprietary search engine as a solution. The more open the technology, the more able we are to refine it to meet our client’s needs.”

If you’d like more information on the pros and cons of Open Source Search Engines vs. Proprietary Search Engines that are specific to your business or organization’s needs, feel free to contact us for a free consultation.

Dynamic Fields in Apache Solr

by Jeff Peck

So, you’ve installed a fresh copy of Apache Solr. You have tested it out running the examples from the Solr tutorial. And now you are ready to start indexing some of your own data. Just one problem. The fields for your data are not recognized by the default Solr instance. You notice in the schema.xml file that the default fields have names like cat, weight, subject, includes, author, title, payloads, popularity, price, etc. These fields are defined for the purpose of being used with the sample data provided with Solr. Most of their names are likely not relevant to your dataset, and even if you can manage to make things “fit” with misnamed fields even just for the purpose of experimenting, you also face the problem that their set properties may not be what you would expect them to be.

Of course you can modify the schema.xml file and apply strong data-typing to each field that you plan to use to fit the exact needs of your project, reload Solr, and then start to index your data. But if you are just getting started with Solr, or starting a new project and experimenting with adding to your dataset, you may not know exactly what fields you need to define or what properties to define for them. Or you might be interested updating an existing index with some additional fields, but do not want to explicitly add them to the schema.

Fortunately, Solr gives the option to define dynamic fields. Further, there are pre-defined dynamic fields for many of the common data-types in the default schema. Here are the some of the dynamic fields that are found in the default schema.xml:

<dynamicField name="*_i"  type="int"    indexed="true"  stored="true"/>
<dynamicField name="*_s"  type="string"  indexed="true"  stored="true"/>
<dynamicField name="*_l"  type="long"   indexed="true"  stored="true"/>
<dynamicField name="*_t"  type="text"    indexed="true"  stored="true"/>
<dynamicField name="*_b"  type="boolean" indexed="true"  stored="true"/>
<dynamicField name="*_f"  type="float"  indexed="true"  stored="true"/>
<dynamicField name="*_d"  type="double" indexed="true"  stored="true"/>
<dynamicField name="*_dt" type="date"    indexed="true"  stored="true"/>

The field names are defined with a glob-like pattern that is either at the beginning or end of the name. With the above dynamic fields, you can index data with field names that begin with any valid string and end in one of the suffixes in the name attributes (i.e. article_title_s, article_content_t, posted_date_dt, etc.) and Solr will dynamically create any dynamic field of the particular type with the name that you give it.

<add>
<doc>
<field name="article_title_s">My Article</field>
<field name="article_content_t">Lorem Ipsum...</field>
<field name="posted_date_dt">1995-12-31T23:59:59Z</field>
</doc>
</add>

After you’ve indexed some data, you can actually view the dynamic field names in the schema viewer, located at http://YOUR-INSTANCE/admin/schema.jsp

Using dynamic fields is a great way to get started at using Apache Solr with minimal setup.  If you need assistance with setting up or integrating Solr, contact us.  We can step in at any point in a project to offer assistance or perform and entire upgrade to Solr.

How to Index a Site with Python Using solrpy and a Sitemap

by Jeff Peck

If you are looking for a fast and easy way to populate a Solr instance using Python, read on.

The script provided here is a basic starting point to building the Solr index for any website with a sitemap, within minutes.  Simply modify the script to use your Solr instance and run with a path to your valid XML sitemap and it will begin populating your Solr index.

While you certainly can modify this script to fit your specific needs, you may even find that this script satisfies your Solr indexing requirements as-is.

To start, you need to be running Python 2.6 and have the following modules installed:

You can install these using easy_install or manually.

You will also require an Apache Solr instance.  (If you are looking for fully managed solution for hosting your Solr search application with a wide range of services, feel free to contact us.)

Ideally you will use this script on your own sitemap.  For detailed information on how to construct your sitemap click here: http://www.sitemaps.org/protocol.php.  You can search the web for other scripts that will automatically make sitemaps out of common CMS’s like WordPress and Joomla.  There are also sitemap generators available. You can also find a valid sitemap for testing here: http://www.google.com/sitemap.xml (~4Mb). We will assume that you have have a valid sitemap.

We will also assume that you have the default Solr schema.xml installed.

Write the following python script sitemap-indexer.py, replacing the value for solrUrl with the location of your own instance:

#! /usr/bin/env python
""" Index links from a sitemap to a SOLR instance"""

import sys
from BeautifulSoup import BeautifulSoup
import solr
import hashlib
import urllib2
from xml.etree.ElementTree import parse

# How many iterations max?  Enter 0 for no limit.
limit = 0 

# The URL of the solr instance
solrUrl = 'http://localhost:8080/sitemap-indexer-test'

# The xmlns for the sitemap schema
sitemaps_ns = 'http://www.sitemaps.org/schemas/sitemap/0.9'

if len(sys.argv) != 2:
	print 'Usage: ./sitemap-indexer.py path'
	sys.exit(1)

sitemapTree = parse(sys.argv[1])

solrInstance = solr.SolrConnection(solrUrl) # Solr Connection object

counter = 0
numAdded = 0

# Find all of the URLs in the form <url>...<loc>URL</loc>...</url>
for urlElem in sitemapTree.findall('{%s}url/{%s}loc'%(sitemaps_ns,sitemaps_ns)):
	counter = counter + 1 # Increment counter

	if limit > 0 and counter > limit:
		# For testing, if the limit is reached, break
		break;

	url = urlElem.text # Get the url text from the element

	try: # Try to get the page at url
		response = urllib2.urlopen(url)
	except:
		print "Error: Cannot get content from URL: "+url
		continue # Cannot get HTML.  Skip.

	try: # Try to parse the HTML of the page
		soup = BeautifulSoup(response.read())
	except:
		print "Error: Cannot parse HTML from URL: "+url
		continue # Cannot parse HTML.  Skip.

	if soup.html == None: # Check if there is an <html> tag
		print "Error: No HTML tag found at URL: "+url
		continue #No <html> tag.  Skip.

	try: # Try to set the title
		title = soup.html.head.title.string.decode("utf-8")
	except:
		print "Error: Could not parse title tag found at URL: "+url
		continue #Could not parse <title> tag.  Skip.

	try: # Try to set the body
		body = str(soup.html.body).decode("utf-8")
	except:
		print "Error: Could not parse body tag found at URL: "+url
		continue #Could not parse <body> tag.  Skip.

	# Get an md5 hash of the url for the unique id
	url_md5 = hashlib.md5(url).hexdigest()

	try: # Add to the Solr instance
		solrInstance.add(id=url_md5,url_s=url,text=body,title=body)
	except Exception as inst:
		print "Error adding URL: "+url
		print "\tWith Message: "+str(inst)
	else:
		print "Added Page \""+title+"\" with URL "+url
		numAdded = numAdded + 1

try: # Try to commit the additions
	solrInstance.commit()
except:
	print "Could not Commit Changes to Solr Instance - check logs"
else:
	print "Success. "+str(numAdded)+" documents added to index"

Make the script executable and run it:
./sitemap-indexer.py /path/to/sitemap.xml

It will start to go through the sitemap, parsing the content of each URL and if no errors found will add it to the Solr index. This process can take several minutes. There may be errors parsing many of the documents. They will simply be skipped, you may have to fine-tune the parser to fit your specific needs.

Once finished, it will output the number of documents that were committed to the Solr index.

You should be able to access your Solr Instance and run queries. There are numerous resources on the web to help you form query strings. There is also a query form in your Solr web admin interface that allows setting the various request parameters.

If you experience Solr Exceptions, check your Solr logs. If you modified your schema, be sure to reload your Solr instance as this may be the cause of Unrecognized Field Exceptions. You can find the default Solr schema in the example/solr/ directory of a new install of Solr.

If you need assistance with any part of the Solr implementation, feel free to contact us.  We can get you started, step in and assist, or perform and entire integration of a Solr solution.

If you would like to parse the documents for more specific tags than simply taking the entire body element (as this script does), refer to this documentation:
http://www.crummy.com/software/BeautifulSoup/documentation.html.