Response Writers

JSON Response Writer

The default Solr Response Writer is the JsonResponseWriter, which formats output in JavaScript Object Notation (JSON), a lightweight data interchange format specified in specified in RFC 4627. If you do not set the wt parameter in your request, you will get JSON by default.

Here is a sample response for a simple query like q=id:VS1GB400C3:

{
  "responseHeader":{
    "zkConnected":true,
    "status":0,
    "QTime":7,
    "params":{
      "q":"id:VS1GB400C3"}},
  "response":{"numFound":1,"start":0,"maxScore":2.3025851,"docs":[
      {
        "id":"VS1GB400C3",
        "name":["CORSAIR ValueSelect 1GB 184-Pin DDR SDRAM Unbuffered DDR 400 (PC 3200) System Memory - Retail"],
        "manu":["Corsair Microsystems Inc."],
        "manu_id_s":"corsair",
        "cat":["electronics",
          "memory"],
        "price":[74.99],
        "popularity":[7],
        "inStock":[true],
        "store":["37.7752,-100.0232"],
        "manufacturedate_dt":"2006-02-13T15:26:37Z",
        "payloads":["electronics|4.0 memory|2.0"],
        "_version_":1549728120626479104}]
  }}

The default mime type for the JSON writer is application/json, however this can be overridden in the solrconfig.xml - such as in this example from the “techproducts” configuration:

<queryResponseWriter name="json" class="solr.JSONResponseWriter">
  <!-- For the purposes of the tutorial, JSON response are written as
       plain text so that it's easy to read in *any* browser.
       If you are building applications that consume JSON, just remove
       this override to get the default "application/json" mime type.
    -->
  <str name="content-type">text/plain</str>
</queryResponseWriter>

Standard XML Response Writer

The XML Response Writer is the most general purpose and reusable Response Writer currently included with Solr. It is the format used in most discussions and documentation about the response of Solr queries.

Note that the XSLT Response Writer can be used to convert the XML produced by this writer to other vocabularies or text-based formats.

The behavior of the XML Response Writer can be driven by the following query parameters.

XSLT Response Writer

The XSLT Response Writer applies an XML stylesheet to output. It can be used for tasks such as formatting results for an RSS feed.

<!--
  Changes to XSLT transforms are taken into account
  every xsltCacheLifetimeSeconds at most.
-->
<queryResponseWriter name="xslt"
                     class="org.apache.solr.request.XSLTResponseWriter">
  <int name="xsltCacheLifetimeSeconds">5</int>
</queryResponseWriter>

Binary Response Writer

This is a custom binary format used by Solr for inter-node communication as well as client-server communication. SolrJ uses this as the default for indexing as well as querying. See Client APIs for more details.

GeoJSON Response Writer

Returns Solr results in GeoJSON augmented with Solr-specific JSON. To use this, set wt=geojson and geojson.field to the name of a spatial Solr field. Not all spatial fields types are supported, and you’ll get an error if you use an unsupported one.

Python Response Writer

Solr has an optional Python response format that extends its JSON output in the following ways to allow the response to be safely evaluated by the python interpreter:

PHP Response Writer and PHP Serialized Response Writer

Solr has a PHP response format that outputs an array (as PHP code) which can be evaluated. Setting the wt parameter to php invokes the PHP Response Writer.

Example usage:

$code = file_get_contents('http://localhost:8983/solr/techproducts/select?q=iPod&wt=php');
eval("$result = " . $code . ";");
print_r($result);

Solr also includes a PHP Serialized Response Writer that formats output in a serialized array. Setting the wt parameter to phps invokes the PHP Serialized Response Writer.

Example usage:

$serializedResult = file_get_contents('http://localhost:8983/solr/techproducts/select?q=iPod&wt=phps');
$result = unserialize($serializedResult);
print_r($result);

Ruby Response Writer

Solr has an optional Ruby response format that extends its JSON output in the following ways to allow the response to be safely evaluated by Ruby’s interpreter:

Here is a simple example of how one may query Solr using the Ruby response format:

require 'net/http'
h = Net::HTTP.new('localhost', 8983)
hresp, data = h.get('/solr/techproducts/select?q=iPod&wt=ruby', nil)
rsp = eval(data)
puts 'number of matches = ' + rsp['response']['numFound'].to_s
#print out the name field for each returned document
rsp['response']['docs'].each { |doc| puts 'name field = ' + doc['name'\] }

CSV Response Writer

The CSV response writer returns a list of documents in comma-separated values (CSV) format. Other information that would normally be included in a response, such as facet information, is excluded.

The CSV response writer supports multi-valued fields, as well aspseudo-fields, and the output of this CSV format is compatible with Solr’s CSV update format.

id,cat,name,popularity,price,score
IW-02,"electronics,connector",iPod & iPod Mini USB 2.0 Cable,1,11.5,0.98867977
F8V7067-APL-KIT,"electronics,connector",Belkin Mobile Power Cord for iPod w/ Dock,1,19.95,0.6523595
MA147LL/A,"electronics,music",Apple 60 GB iPod with Video Playback Black,10,399.0,0.2446348

Velocity Response Writer

The VelocityResponseWriter processes the Solr response and request context through Apache Velocity templating.

See the Velocity Response Writer section for details.

Smile Response Writer

The Smile format is a JSON-compatible binary format, described in detail here: http://wiki.fasterxml.com/SmileFormat.

XLSX Response Writer

Use this to get the response as a spreadsheet in the .xlsx (Microsoft Excel) format. It accepts parameters in the form colwidth.<field-name> and colname.<field-name> which helps you customize the column widths and column names.

This response writer has been added as part of the extraction library, and will only work if the extraction contrib is present in the server classpath. Defining the classpath with the lib directive is not sufficient. Instead, you will need to copy the necessary .jars to the Solr webapp’s lib directory manually. You can run these commands from your $SOLR_INSTALL directory:

cp contrib/extraction/lib/*.jar server/solr-webapp/webapp/WEB-INF/lib/
cp dist/solr-cell-6.3.0.jar server/solr-webapp/webapp/WEB-INF/lib/

Once the libraries are in place, you can add wt=xlsx to your request, and results will be returned as an XLSX sheet.