Solr: where to find the Luke request handler - solr

I'm trying to get a list of all the fields, both static and dynamic, in my Solr index. Another SO answer suggested using the Luke Request Handler for this.
It suggests finding the handler at this url:
http://solr:8983/solr/admin/luke?numTerms=0
When I try this url on my server, however, I get a 404 error.
The admin page for my core is here http://solr:8983/solr/#/mycore, so I also tried http://solr:8983/solr/#/mycore/admin/luke. This also gave me another 404.
Does anyone know what I'm doing wrong? Which url should I be using?

First of all you have to enable the Luke Request Handler. Note that if you started from the example solrconfig.xml you probably don't need to enable it explicitly because
<requestHandler name="/admin/" class="solr.admin.AdminHandlers" />
does it for you.
Then if you need to access the data programmatically you have to make an HTTP GET request to http://solr:8983/solr/mycore/admin/luke (no hash mark!). The response is in XML but specifying wt parameter you can obtain different formats (e.g. http://solr:8983/solr/mycore/admin/luke?wt=json)
If you only want to see fields in SOLR web interface select your core from the drop down menu and then click on "Schema Browser"

In Solr 6, the solr.admin.AdminHandlers has been removed. If your solrconfig.xml has the line <requestHandler name="/admin/" class="solr.admin.AdminHandlers" />, it will fail to load. You will see errors in the log telling you it failed to load the class org.apache.solr.handler.admin.AdminHandlers.
You must include in your solrconfig.xml the line,
<requestHandler name="/admin/luke" class="org.apache.solr.handler.admin.LukeRequestHandler" />
but the URL is core-specific, i.e. http://your_server.com:8983/solr/your_core_name/admin/luke
And you can specify the parameters fl,numTerms,id,docId as follows:
/admin/luke
/admin/luke?fl=cat
/admin/luke?fl=id&numTerms=50
/admin/luke?id=SOLR1000
/admin/luke?docId=2

You can use this Luke tool which allows you to explore Lucene index.
You can also use the solr admin page :
http://localhost:8983/solr/#/core/schema-browser

Related

How to prevent crawling external links with apache nutch?

I want to crawl only specific domains on nutch. For this I set the db.ignore.external.links to true as it was said in this FAQ link
The problem is nutch start to crawl only links in the seed list. For example if I put "nutch.apache.org" to seed.txt, It only find the same url (nutch.apache.org).
I get the result by running crawl script with 200 depth. And it's finished with one cycle and generate the out put below.
How can I solve this problem ?
I'm using apache nutch 1.11
Generator: starting at 2016-04-05 22:36:16
Generator: Selecting best-scoring urls due for fetch.
Generator: filtering: false
Generator: normalizing: true
Generator: topN: 50000
Generator: 0 records selected for fetching, exiting ...
Generate returned 1 (no new segments created)
Escaping loop: no more URLs to fetch now
Best Regards
You want to fetch only pages from a specific domain.
You already tried db.ignore.external.links but this restrict anything but the seek.txt urls.
You should try conf/regex-urlfilter.txt like in the example of the nutch1 tutorial:
+^http://([a-z0-9]*\.)*your.specific.domain.org/
Are you using "Crawl" script? If yes make sure you giving level which is greater than 1. If you run something like this "bin/crawl seedfoldername crawlDb http://solrIP:solrPort/solr 1". It will crawl only urls which are listed in the seed.txt
And to crawl specific domain you can use regex-urlfiltee.txt file.
Add following property in nutch-site.xml
<property>
<name>db.ignore.external.links</name>
<value>true</value>
<description>If true, outlinks leading from a page to external hosts will be ignored. This is an effective way to limit the crawl to include only initially injected hosts, without creating complex URLFilters. </description>
</property>

Solr Adding PDF via ExtractRequestHandler

I am trying to use the Solr handler to add a PDF document to the index but keep getting a missing Unique field error (even though I am providing the field). Here is the request:
D:\Downloads\solr-4.6.0\solr-4.6.0\example\exampledocs>c:\temp\curl "http://loca
lhost:8983/solr/update/extract?commit=true&literal.MessageID=2b071dce-d7a6-4b7c-
9a09-33cc93f96db9" -F "myfile=#Wizards vs Warriors tickets.pdf"
The error I get back is:
<?xml version="1.0" encoding="UTF-8"?>
<response>
<lst name="responseHeader"><int name="status">400</int><int name="QTime">135</in
t></lst><lst name="error"><str name="msg">Document is missing mandatory uniqueKe
y field: MessageID</str><int name="code">400</int></lst>
</response>
In my REST call I am using literal.MessageID=... but it still seems to not find it.
Any ideas on how I can troubleshoot this? (NOTE: I did find an article on SO about problems with fields ending in ID so I removed the ID from the field in the schema and modified the literal.Message but still same issue.
Thanks,
I tried your test case and found the same result. Then I did several test cases and found that the required unique key field name should be always in lowercase. That's why when you try with MessageID, it doesn't work.
Try with messageid. It'll work.

Map static field between nutch and solr

I use nutch 1.4 and I would like to map static field to Solr.
I know there is the index-static plugin. I configured it in nutch-site.xml like this :
<property>
<name>index-static</name>
<value>field:value</value>
</property>
However, the value is not sent to Solr.
Does anyone have a solution ?
It looks like the entry in nutch-default.xml is wrong.
According to the plugin source "index.static" instead of "index-static" is the right name for the property.
String fieldsString = conf.get("index.static", null);
After using that in my nutch-site.xml I was able to send multiple fields to my solr server.
Also make sure that the plugin is added to list of included plugins in the "plugin.includes" property.

how to configure XsltUpdateRequestHandler

I'm looking for a simple example of configuring XsltUpdateRequestHandler.
The SOLR config in 3.4.0 is minimal:
<!-- XSLT Update Request Handler
Transforms incoming XML with stylesheet identified by tr=
-->
<requestHandler name="/update/xslt"
startup="lazy"
class="solr.XsltUpdateRequestHandler" />
And the SOLR wiki page is virtually non-existent ("TODO: Write a better documentation"):
http://wiki.apache.org/solr/XsltUpdateRequestHandler
I guess I really want to know how to point to a specific XSL file, because I find the line "Transforms incoming XML with stylesheet identified by tr=" a bit cryptic.
You could simply add an XSL style sheet to the solr/conf/xslt directory.
You can then use the XsltUpdateRequestHandler, and specify that stylesheet when you index the document.
For example:
curl "http://localhost:8983/solr/update/xslt?commit=true&tr=rss2solr.xsl" -H "Content-Type: text/xml" --data-binary #blogrss.xml
For details, a nice article explains in detail. (Free to download)

Indexing PDF with Solr

Can anyone point me to a tutorial.
My main experience with Solr is indexing CSV files. But I cannot find any simple instructions/tutorial to tell me what I need to do to index pdfs.
I have seen this: http://wiki.apache.org/solr/ExtractingRequestHandler
But it makes very little sense to me. Do I need to install Tika?
Im lost - please help
With solr-4.9 (the latest version as of now), extracting data from rich documents like pdfs, spreadsheets(xls, xlxs family), presentations(ppt, ppts), documentation(doc, txt etc) has become fairly simple.
The sample code examples provided in the downloaded archive from
here contains a basic solr template project to get you started quickly.
The necessary configuration changes are as follows:
Change the solrConfig.xml to include following lines :
<lib dir="<path_to_extraction_libs>" regex=".*\.jar" />
<lib dir="<path_to_solr_cell_jar>" regex="solr-cell-\d.*\.jar" />
create a request handler as follows:
<requestHandler name="/update/extract"
startup="lazy"
class="solr.extraction.ExtractingRequestHandler" >
<lst name="defaults" />
</requestHandler>
2.Add the necessary jars from the solrExample to your project.
3.Define the schema as per your needs and fire a query like :
curl "http://localhost:8983/solr/collection1/update/extract?literal.id=1&literal.filename=testDocToExtractFrom.txt&literal.created_at=2014-07-22+09:50:12.234&commit=true" -F "myfile=#testDocToExtractFrom.txt"
go to the GUI portal and query to see the indexed contents.
Let me know if you face any problems.
You could use the dataImportHandler. The DataImortHandle will be defined at the solrconfig.xml, the configuration of the DataImportHandler should be realized in an different XML config file (data-config.xml)
For indexing pdf's you could
1.) crawl the directory to find all the pdf's using the FileListEntityProcessor
2.) reading the pdf's from an "content/index"-XML File, using the XPathEntityProcessor
If you have the list of related pdf's, use the TikaEntityProcessor
look at this http://solr.pl/en/2011/04/04/indexing-files-like-doc-pdf-solr-and-tika-integration/ (example with ppt) and this Solr : data import handler and solr cell
The hardest part of this is getting the metadata from the PDFs, using a tool like Aperture simplifies this. There must be tonnes of these tools
Aperture is a Java framework for extracting and querying full-text content and metadata from PDF files
Apeture grabbed the metadata from the PDFs and stored it in xml files.
I parsed the xml files using lxml and posted them to solr
Use the Solr, ExtractingRequestHandler. This uses Apache-Tika to parse the pdf file. I believe that it can pull out the metadata etc. You can also pass through your own metadata.
Extracting Request Handler
public class SolrCellRequestDemo {
public static void main (String[] args) throws IOException, SolrServerException {
SolrClient client = new
HttpSolrClient.Builder("http://localhost:8983/solr/my_collection").build();
ContentStreamUpdateRequest req = new
ContentStreamUpdateRequest("/update/extract");
req.addFile(new File("my-file.pdf"));
req.setParam(ExtractingParams.EXTRACT_ONLY, "true");
NamedList<Object> result = client.request(req);
System.out.println("Result: " +enter code here result);
}
This may help.
Apache Solr can now index all sort of binary files like PDF, Words, etc ... check out this doc:
https://lucene.apache.org/solr/guide/8_5/uploading-data-with-solr-cell-using-apache-tika.html

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