Advanced crawler configuration
The crawler handles on-going indexing for website content, which means that it will add, update, and delete pages from your Collection as the content is added, updated, and removed from the associated sites. Here we outline some more advanced features of the Crawler, see Crawling a website for a quick way to get up and running.
What data is indexed by default?
The crawler extracts metadata from each page and condenses it into a standard set of fields to be added to the search index.
The crawler uses page metadata and content to construct a standardized set of fields:
- URL (
url). The full URL of the page
- Title (
title). The meta-title of the page
- Image (
image). URL for the page image
- Language (
lang). Language of the page content (
- Description (
description). The meta description of the page
- Keywords (
keywords). List of keywords for the page
- Modified Time (
modified_time). The time when the page was last modified
- Published Time (
published_time). The time when the page was first published
- Headings (
headings). List of headings from the body of the page
Fields derived from the URL are also included for common queries (e.g. limiting to a domain or particular sub-URL structure of a site):
- Domain (
domain). The domain of the URL
- First directory (
dir1). The first directory of the URL, or empty if none
- Secondary directory (
dir2). The second directory of the URL, or empty if none
In addition to the above, the following metadata is also extracted if available:
- All meta tags within head
- OpenGraph tags
- Custom SJ tags
- Body content (
Note: The page
<body> is indexed but not added as a field. This means that queries can match against the content, but the text cannot be returned in a search result.
When multiple metadata types are used for a given field, the crawler will use OpenGraph values over others.
- Page title:
- Page description:
<body> is summarised to provide a more concise base for searching. This process discards text inside
To test what content of a webpage is indexed, use our Page debug tool
Indexing additional fields
- Add a schema field (e.g.
authors) and select the desired schema field type.
- Add custom tags to your webpage or content.
- Index a page containing the custom field via diagnose tool. Use the preview section to check that the additional field was indexed correctly.
- Re-index all domains so all records are updated.
Adding custom meta tags to your webpage:
Filters and facets often use additional fields to provide better searching and filtering capabilities. For example, a news site might want to filter by topic or a documentation site by version.
Custom meta tags allow you to add those additional fields to your records. Meta tags are defined in HTML by adding
data attributes to elements. To avoid name clashes with other systems, data attributes must contain the prefix
Defining custom fields in
By default the crawler reads
<meta> tags within
<head>, but only keeps standard fields (title, description, keywords, etc). Add a
data-sj-field="fieldname" attribute to override this behaviour and create a custom field from the meta tag's
content attribute. This example shows an otherwise ignored
<meta> tag being converted into a custom field
<meta property="custom meta field" data-sj-field="fieldname" content="fieldvalue" />
Defining custom fields in
To capture data already rendered within an element, add
data-sj-field="fieldname" to it:
<span data-sj-field="random">This text is the value</span>
This will set custom field
random="This text is the value".
If you don't want the data rendered on the page, then you can also set the field value using the data attribute.
<span data-sj-field="fieldname" data-sj-value="fieldvalue"> This text is not used because the data attribute has a value </span>
Adding data to a list field type
It is possible to add a list of values by repeating the same tag multiple times. You just need to ensure that the schema field type is a 'List of String/Integers/etc'.
<meta data-sj-field="topics" content="Art"/> <meta data-sj-field="topics" content="Biology"/> <meta data-sj-field="topics" content="Chemistry"/>
In the example above, the strings "Art, Biology, Chemistry" will be stored as a list against the field
Note: If you have multiple meta tags on your page for a specific field but the schema field type is not a list, we will not index that webpage.
Problem: I have very locally targeted content and wish to recommend local content based on my site visitor location. Solution: On each "locally" targeted content page, add two pieces of meta information as follows. e.g.
<span data-sj-field="lat" data-sj-value="-33.867487"></span> <span data-sj-field="lng" data-sj-value="181.3615434"></span>
In the above case, the prefix data-sj-field indicates this is information specific to the page.
data-sj-field="lat" indicates this page has a property called "lat" with corresponding value -33.867487.
Processed meta data vs Raw meta data
Processed metadata is the metadata that is stored in the index. Raw metadata is read by the crawler, but may not be indexed in the search index. An example of raw metadata is links on a webpage that may be useful for the crawler to find linked pages, but do not need to be recorded in the search index.
All indexed pages are recrawled every 3-6 days. See instant-indexing for detecting changes and updating them immediately.
Canonicals and redirects
Canonicals and redirects are followed.
Indexing non-linked pages
It is common to find pages that are not linked in header, footer, navigation or from anywhere else on the website. There are two ways to make sure such pages are also added to the search index:
Preventing pages from being indexed
To stop a page from being indexed, add the attribute
data-sj-noindex to an HTML element on the page.
<meta name="noindex" content="noindex" data-sj-noindex />
Note: although this will prevent our crawler from indexing the page, it will not stop other crawlers. Use the attribute on the standard "robots noindex meta tag" to prevent all crawlers from indexing the page:
<meta name="robots" content="noindex" data-sj-noindex />
Debugging a page
The 'Page debug' tool allows you to see how data is extracted from your pages by our crawler.
After Diagnosing a page click on 'See extended debug information' to use the Page debug tool. The Page debug tool crawls your webpage or document and gives you details of all the extracted metadata, content, open graph data, and schema.org data from your web page.
The Page debug tool allows you to identify existing issues with your pages that deteriorate the quality of search data such as missing metadata, missing canonicals, incorrect mark-up, lack of content, and incorrect redirects.
Site Search Health Report
Another tool that you can use to check for errors across your whole domain rather than a specific web page is the Search Health Report.
The Search Health Report contains helpful information about your content, meta data, URL structure, query parameters, and server configuration. You also get this report emailed to you when you add a new domain or create a new collection using Sajari console.