Synapticloop PANL

 anl Server

Rapidly get up and running with a fully featured, SEO friendly, keyword searchable, faceted search engine with an in-built, search page to test it all out.

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Latest release tag:

Latest release:

Major branch release status:

BRANCH	STATUS	TYPE
MAIN		Trunk - integrates with the latest Solr version (currently 9)
SOLR PANL 9		Panl version for integrating with Solr version 9
SOLR PANL 8		Panl version for integrating with Solr version 8
SOLR PANL 7		Panl version for integrating with Solr version 7
hidden-summer		Panl development release version 2.1.0

We always recommend that you use the most recently available release which contains bug fixes and new functionality and is generally backwards compatible.

The Synapticloop Panl project uses major.minor.micro versioning, the meaning of which:

• major - the major version will increment when there is a BREAKING CHANGE to the Panl LPSE URL. Upon increment of the major version, both the minor and micro version number will be reset to 0 (zero).
• minor - the minor version will increment when there is additional functionality added to the release. Upon increment of the minor version, the micro number will be reset to 0 (zero).
• micro - the micro version will increment for bug fixes only.

The book version matches the version of the Synapticloop Project version. Any changes to the book without any changes to the codebase will be updated on the main branch and the ghpages based website will be updated.

ANy out-of-band book updates will not be reflected in the panl code release updates.

Instructions

Download the Panl Server Release

1. https://github.com/synapticloop/panl/releases
2. Read the 5-Step Quick Start section
3. Done.

Upgrading the Panl Server Release

IMPORTANT !!!

Version 2.0.0 is a breaking change with version 1.*.*,

Both the LPSE URL and the JSON response have changes.

Panl is designed to be a drop in replacement for your current version. Although backwards compatibility is always the highest priority, do keep an eye out in the release notes for any breaking features.

Your existing configuration files should just work with the downloaded release package.

Read the Documentation

• Online book ( HTML): https://synapticloop.github.io/panl/
• Offline book ( PDF): Getting Started With Synapticloop Panl.pdf (over 500 pages of documentation, written with you, the integrator, in mind)

Both of the book links above refer to Solr Panl integration 9 with instructions for setting up and running earlier versions of Solr.

Why?

Because...

/Caran d'Ache/true/Black/bDW/

looks A LOT nicer than

q=*:*&facet.mincount=1&rows=10&facet.field=lead_size_indicator&facet.field=grip_material&facet.field=colours&facet.field=nib_shape&facet.field=diameter&facet.field=cap_shape&facet.field=brand&facet.field=mechanism_type&facet.field=length&facet.field=hardness_indicator&facet.field=grip_type&facet.field=cap_material&facet.field=lead_grade_indicator&facet.field=tubing_material&facet.field=in_built_sharpener&facet.field=disassemble&facet.field=category&facet.field=body_shape&facet.field=clip_material&facet.field=mechanism_material&facet.field=lead_length&facet.field=body_material&facet.field=in_built_eraser&facet.field=grip_shape&facet.field=relative_weight&facet.field=name&facet.field=nib_material&facet.field=weight&facet.field=variants&facet=true&fq=brand:"Caran+d'Ache"&fq=disassemble:"true"&fq=colours:"Black"&q.op=AND

Why Synapticloop Panl?

Panl was designed to convert rather long and unfriendly (both in human-readable and SEO terms) to shorter, nicer, and friendlier URL paths throughout the entire search journey.

Working with a Solr schema, the Panl configuration files translate unwieldy URL parameters into concise and precise URL paths.

• Have SEO friendlier URL paths with much shorter URLs than traditional query parameters - This was the primary driver and the base functionality.

• Abstract away the complexities of the Solr query string - Being able to have a simple interface through the URL which could generate complex queries. Not having to fully understand how Solr works in the back-end abstracts away the complexity of a front-end integrator and reduces the need to have the back-end and front-end understand each-other.

• Be quick to start up and easy to configure - During development of a solution, being able to iterate over a solution, or change the way that Panl is configured is a must have. Additionally, being able to upgrade the Panl server and have the configuration files be automatically picked up and work without any changes is a plus.

• Protect Solr from errant queries - Hiding the Solr implementation details from the end user and parsing, decoding, and validating the URL before passing the query through to Solr. Additionally, Solr has a tendency to return an internal server error when the query string is not as it expected, and this should not disturb the return of the results.

• Be able to present the same Solr collection in multiple different ways - A single Solr collection should be able to serve up different fields and facets from the result documents without any back-end logic.

• **Have a configuration file drive the generation of the UI as much as possible ** - Rather than hard-coding facets and then determining how to display them, being able to have a returned JSON response which can be interrogated to determine how the facets should be displayed.

Additional Panl Niceties

1. MULTIPLE ways to 'SLICE and DICE' - From one Solr collection, the Panl server can present the results and facets in multiple different ways, providing individual use cases for specific needs.

2. PREFIXES and SUFFIXES - Panl can also add prefixes and suffixes to the URI path to increase readability, for example, with configuration. For the example LPSE URI path of

   /Caran d'Ache/true/Black/bDW/

   could also have the brand Solr field prefixed with ‘Manufactured By ’ and suffixed by ‘ Company’ to produce the URI path

   /Manufactured By The Caran d'Ache Company/true/Black/bDW/

3. BOOLEAN value translations, for any Solr field that is defined as a solr.BoolField, then an additional translation can be performed. ‘True’ and ‘false’ values can be replaced with arbitrary text, which will be transparently converted between Panl and Solr. For the LPSE URI path of

   /Caran d'Ache/true/Black/bDW/

   the true value (which is defined as whether the mechanical pencil can be disassembled could be changed to ‘Able to be disassembled’ for true values, and ‘Cannot be disassembled’ for false values.

   The above URI path would then become

   /Caran d'Ache/Able to be disassembled/Black/bDW/

4. BOOLEAN checkboxes - Whilst this may seem obvious to have a checkbox for a true/false value, the checkboxes work in a subtly different way. By selecting the checkbox, the only one of facet values will be selected when deselected, the BOOLEAN facet is in a don't care start - the facet value can be either of the values.

5. CONDENSE multiple field values - Rather than having a forward slash URL path separator for multiple values of the same facet (used in OR Facets and Multi-valued REGULAR facets), Panl can be configured to condense these values into a single path part, saving URL characters, and reducing URL length, and making the URL far more human-readable. For example, selecting pencils manufactured by Faber-Castell OR Koh-i-Noor could have the URI path of

   /Manufactured by Koh-i-Noor/Manufactured by Faber-Castell/bb/,

   with condensed multiple field values - this could be configured to become

   /Manufactured by Koh-i-Noor, or Faber-Castell Co./b/

   (with a value separator configured to be , or ).

6. SEARCH ALL OR SPECIFIC SOLR FIELDS - Any Solr field that is analysed can be selected to be searched on, for example, in the Book Store Walkthrough, the user can select to search within the title, the author, the description, or all of them. Also configure the query time boost.

7. FIELD VALUE validation - By default, Solr can error when an invalid value is passed through - for example, if Solr is expecting a numeric value and it could not be parsed. Panl can protect against this, by attempting to parse the value as best it can, and silently dropping the parameter if it cannot be sensibly parsed.

8. HIERARCHICAL facets - Only show facets if a parent facet is currently selected, allowing you to narrow down the facet results and lead users through the search journey.

9. UNLESS facets - Continue to show a facet unless another specified facet is selected. This can be thought of as the inverse of a hierarchical facet.

10. SORTED facets - Each individual facet can be sorted by either the facet count (which is the default), or the facet value (e.g. alphabetic/numeric)

11. MORE facets - Request more facets where the number of facets return does not contain the full set.

12. RESULTS SORTING options - Sort by any of the Solr fields, either ascending, or descending and with multiple sub-sorting available - e.g. sorting by a brand name, than the model number. Additionally Panl generates URLs for the inverse of the sorting without impacting any sub-sorting.

13. INTEGRATED TYPEAHEAD/LOOKAHEAD - Retrieve results suggestions as you type in the query search box.

14. PAGINATION - All the data to easily generate pagination URL paths giving you options and control over your own implementation.

15. STATIC SITE GENERATION - With the exception of a query parameter, all available links for every conceivable URI path can be statically generated ahead of time, all with canonical URLs. Additionally, for search results which do not change frequently, the Panl JSON response Object can be cached for faster lookups.

16. STATELESS - No state is stored in the Panl server, all state is from the URL path part that is passed through. No sessions, no memory, nothing to backup, easy to update and quick to start and restart.

17. CACHEABLE - Unless the underlying Solr search document index changes, each Solr request is able to be cached.

18. TEXT CONFIGURATION - All configuration for Panl is based on text files (Java .properties) files so they can be stored in a source code management system. Additionally, upgrades to the Panl server are easy and with quick startup times, any configuration changes will be seen instantly.

Getting up to Speed... Fast!

The Solr Panl release package was designed to get you up and running as quickly as possible.

With the in-built tool, point it at your existing Solr managed-schema.xml file, run the Panl server and view the results. From there you can tweak the configuration, generate new configurations and see your results in an instant.

The Panl Results Viewer Web App

Image: The features and functionality of the Panl Simple Results Viewer Web App

The image is a screenshot of the in-built Panl Results Viewer Web App available in the release package, and whilst not intended as a production search page, can be used to fine-tune the configuration, or just to have a quick overview of the results.

1. A list of available Collections and FieldSet URI Paths (CaFUPs) that Panl is configured to serve. CaFUPs enable different Solr fields to be returned in the documents with the same search parameters.

2. A textual representation of the CaFUPs that the Panl Results Viewer web app is using.

3. The canonical URI path (which is returned with the Panl results JSON object) - this is important as multiple Panl LPSE URI paths will return exactly the same results - this is the unique URI path for this result set and necessary for de-duplicating the search engine results. This also includes a link to the Panl Results Explainer web app.

4. The search query box, by default, Panl responds to the same parameter name as The Solr server - i.e. 'q'. This can be configured to be a different value should you choose.

   Specific Search Fields (not shown) If multiple fields are configured to be searchable, display the fields that are available to search within, and allow the user to select within the field.

5. Active filters - either queries or any of the selected facets that have been used to refine the search results.

6. Active BOOLEAN filters - if the selected facet is a BOOLEAN facet (i.e. either true/false) then a link () can be included to invert this selection (i.e. change the value from true if currently false and vice versa).

7. Active sorting - sorting options that are currently ordering the results - the link is the URI path that will remove this query, facet, or sorting option from the results. If it is an active sorting filter, the Change to DESC or Change to ASC links will invert the sorting order without affecting any further sub-ordering.

8. BOOLEAN Checkboxes - any facets that have been defined as BOOLEAN checkboxes, which allows the integrator to highlight one of the values (either true or false).

9. RANGE filters - for facets that are defined as ranges - allowing end-users to select a range of values - the values are inclusive (i.e. include the minimum and maximum values).

   DATE Range filters (not shown) - Enabling searching on a range of dates (but not a specific date) in the form of: next/previous <any_integer> hours/days/months/years.

   • For example:
   • Last 30 days
   • Previous 24 hours

10. Available filters - additional facets that can further refine and limit the Solr search results.

11. Number of results found, and whether this is an exact match.

12. Query operand - whether the query is OR, or AND, this affects the search query, not the faceting - i.e. the Solr server q.op parameter.

13. Page information, the number of pages, how many results are shown per page, and how many results are shown on this page.

14. Sorting options - Whether to sort by relevance (the default) or by other configured sorting options with ascending and descending options available. Any Solr field can be configured to be used as a sorting option. And multi-sort orders are available, allowing sorting on more than one field.

15. Pagination options - the Panl server returns all information needed to build a pagination system, number of results, number of results shown per page and the current page number.

16. Number of results per page. Able to dynamically set the number of results to return for the query. Note: In the above image, the values 3, 5, 10 are just examples - this can be set to any positive integer number.

17. Timing information about how long the Panl server took to build and return the results (including how much time the Solr server took to find and return the results).

18. The results - the fields that are returned with the documents and are shown in the results sections which are configured by the CaFUPs. Multiple field sets can be configured for the collection.

The Panl Results Explainer Web App

Image: The features and functionality of the Panl results explainer

The image is a screenshot of the in-built Panl Results Explainer Web App available in the release package, and whilst not intended as a production search page, can be used to look into, troubleshoot, and fine-tune the configuration.

1. A list of available Collections and FieldSet URI Paths (CaFUPs) that Panl is configured to serve. CaFUPs enable different Solr fields to be returned in the documents with the same search parameters.
2. A textual representation of the CaFUPs that the Panl Results Viewer web app is using.
3. The canonical URI path entry field allows you to enter any canonical URI path and have the parsing and tokenising explained to you, including whether the parsed token was valid, the LPSE code found and the original value that Panl attempted to decode.
4. The request token explainer - for any canonical URI entered, this will list the parsing and decoding steps, with the following details
   1. Whether the token is valid (if it is invalid, it will be ignored and not passed through to the Solr search server),
   2. The type of token that was found,
   3. The LPSE code,
   4. The parsed value,
   5. The original value, and
   6. Where pertinent, additional information pertaining to the specific code.
5. Configuration parameters - parameters that are not fields or facets with information about the value, a description, and the property that set the value.
6. Field configuration explainer - for each of the fields or facets that are configured in the LPSE order an explanation of their configuration including:
   1. The type of Java field type,
   2. The LPSE code,
   3. The Solr field name,
   4. The Solr field type, the Panl field name, and
   5. Additional configuration items which may include Prefixes, Suffixes, Ranges, Facet type, or Minimum/maximum values
   6. Any configuration warning messages that were found whilst parsing the properties files.

The Panl Single Page Search Web App

Image: The In-Built Panl Single Page Search Web Application

Panl also ships with a URL that will provide a separate JSON response, allowing you to build a single page search interface, giving your users all the options at a glance.

1. A list of available Collections URI Paths for each available single page search interface.
2. The generated Panl LPSE path from the selections.
3. All the facets and the facet values that can be selected.
4. The generated Panl LPSE path from the selections.
5. A search button that will take you the in-built Panl Results Viewer web app so that you can view the results instantly.

Quick Start - The 5 Steps

At the end of this chapter, you will have a web page up and running with the mechanical-pencils collection indexed and ready to sort and facet on the URL: http://localhost:8181/panl-results-viewer/

Image: The In-Built Panl Results Viewer Web Application

0. Download Solr and Panl

Download the latest release of Synapticloop Panl

https://github.com/synapticloop/panl/releases

Download the latest version of Apache Solr - this book is using the 9.6.1-slim version

https://solr.apache.org/downloads.html

A Note On Running The Commands

These are the commands for either Microsoft Windows or NIX operating systems (Linux/Apple Macintosh). Should there be any errors - see the ‘Getting Started’ section for a more in-depth explanation and approach.

---

WARNING: The Solr Release version 9.7.0 has changed the options for creating a new example cloud. The command line option has changed from -noprompt to --no-prompt

All other commands remain the same

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**IMPORTANT**: You will need to replace the
SOLR_INSTALL_DIRECTORY
and
PANL_INSTALL_DIRECTORY
references in the commands for your particular setup.

Windows Commands

**IMPORTANT**: Each of the commands - either Windows or *NIX must be run on a
 single line - watch out for continuations.

1. Create an example cloud instance

This requires no interaction, will use the default setup, two replicas, and two shards under the 'example' cloud node.

Command(s)

cd SOLR_INSTALL_DIRECTORY
bin\solr start -e cloud -noprompt

2. Create the mechanical pencils collection

This will set up the mechanical pencil collection and schema so that the data can be indexed. Command(s)

cd SOLR_INSTALL_DIRECTORY
bin\solr create -c mechanical-pencils -d PANL_INSTALL_DIRECTORY\sample\solr\mechanical-pencils\ -s 2 -rf 2

3. Index the mechanical pencils data

This will index all mechanical pencil data into the Solr instance. Command(s)

cd SOLR_INSTALL_DIRECTORY
bin\solr post -c mechanical-pencils PANL_INSTALL_DIRECTORY\sample\data\mechanical-pencils.json

4. Start the Panl server

This will start the server and be ready to accept requests. Command(s)

cd PANL_INSTALL_DIRECTORY
bin\panl.bat -properties PANL_INSTALL_DIRECTORY\sample\panl\mechanical-properties\panl.properties

5. Start searching and faceting

Open http://localhost:8181/panl-results-viewer/ in your favourite browser.

Choose a collection/fieldset and search, facet, sort, paginate and view the results

*NIX Commands

**IMPORTANT**: Each of the commands - either Windows or *NIX must be run on
 a single line - watch out for continuations.

1. Create an example cloud instance

No prompting, default setup, two replicas, and two shards under the 'example' cloud node. Command(s)

cd SOLR_INSTALL_DIRECTORY
bin/solr start -e cloud -noprompt

2. Create the mechanical pencils collection

Set up the schema so that the data can be indexed. Command(s)

cd SOLR_INSTALL_DIRECTORY
bin/solr create -c mechanical-pencils -d PANL_INSTALL_DIRECTORY/sample/solr/mechanical-pencils/ -s 2 -rf 2

3. Index the mechanical pencils data

Index all of the data into the Solr instance Command(s)

cd SOLR_INSTALL_DIRECTORY
bin/solr post -c mechanical-pencils PANL_INSTALL_DIRECTORY/sample/data/mechanical-pencils.json

4. Start the Panl server

Ready to go. Command(s)

cd PANL_INSTALL_DIRECTORY
bin/panl -properties PANL_INSTALL_DIRECTORY/sample/panl/mechanical-properties/panl.properties

View the in-built Panl Results Viewer web application

5. Start searching and faceting

Open http://localhost:8181/panl-results-viewer/ in your favourite browser.

Choose a collection/fieldset and search, facet, sort, paginate and view the results.

Quick Info

Starting up the example cloud

WARNING: The Solr Release version 9.7.0 has changed the options for starting a new example cloud. The command line option has changed from -cloud to --cloud

All other commands remain the same - For versions greater than 9.7.0 they have re-added the -cloud option

If you have stopped the example Solr server, starting it up:

Windows

cd SOLR_INSTALL_DIRECTORY
bin\solr start -cloud -p 8983 -s "example\cloud\node1\solr"
bin\solr start -cloud -p 7574 -s "example\cloud\node2\solr" -z localhost:9983

*NIX

cd SOLR_INSTALL_DIRECTORY
bin/solr start -cloud -p 8983 -s "example/cloud/node1/solr"
bin/solr start -cloud -p 7574 -s "example/cloud/node2/solr" -z localhost:9983

Build Related Tasks

Updating the Version Number

Gradle looks in the file src/main/resources/gradle.properties for the Panl release version number and the Solr version number that Panl will integrate with.

The two properties are:

• panl.version - the release version
• panl.solr.version - the Solr version for integration

Both of these properties are used to generate the distributable file versions and are used within the code when generating startup output.

Testing the Code

There are three test suites

1. The regular Java unit tests

2. The integration tests

3. The integration spider tess

4. Unit tests

Windows

gradlew.bat test

*NIX

./gradlew test

Integration tests

Note: A Solr server will need to be running, available, and setup with the appropriate collections indexed for this to work.

Windows

gradlew.bat testIntegration

*NIX

./gradlew testIntegration

Integration Spider tests

Note: A Solr server will need to be running, available, and setup with the appropriate collections indexed for this to work.

These tests will spider a running Panl/Solr server for the output and ensure that all links down to two levels contain valid tokens

Windows

gradlew.bat testIntegrationSpider

*NIX

./gradlew testIntegrationSpider

Building the Code

This will build, test, and assemble the distributable

Windows

gradlew.bat build

*NIX

./gradlew build

Assembling the Distributable

This will assemble the distribution

Windows

gradlew.bat assemble

*NIX

./gradlew assemble

The distributions (both a .zip and a .tar file) will be created in the build distributions directory.

I.e.

• ./build/distributions (*NIX), or
• .\build\distributions (Windows)

with the release files named solr-panl-9-x.x.x where x.x.x is the version number.

Version History

2.1.0 Internal niceties (codename hidden-summer) UNDER DEVELOPMENT

2.0.0 - fluffy stuff (codename billowing-feather)

This is a breaking change for the LPSE URL path part

• Breaking Changes

  • [BREAKING CHANGE] Changed range facets LPSE codes from w-w to w- and w+w to w+ (i.e. removed the trailing LPSE code)

• New Features

  • Added in lookahead query handler for Solr panl including panl results viewer lookahead
  • Added in OR SEPARATOR facets so that OR facets can be separated with a string and only have one LPSE code.
  • Added in solr.numrows.maximum property so that this will always be the limit to the number of results returned, this will default to solr.numrows.default
  • Added in BOOLEAN checkbox functionality
  • Ability to select specific search fields added.
  • Added panl.unless.<lpse_code> fields
  • 'Fixed' the keyword search for multiple word so that they use the defined q.op parameter for both default and Specific Solr Search Fields.

• Bug fixes

  • Bug where Panl client will always look for the 'q' parameter for the query, changed to ensure that the correct configured panl.form.query.respondto is used instead
  • Always reset the page to 1 if there is a panl.form.query.respondto URL parameter
  • (Maybe this was a feature?) Updated Single Page search to allow multiple selections for Facets which are multivalued (as opposed to OR Facets)
  • Fixed where a single value LPSE code for a RANGE facet was the first selected item, and other selections would erroneously add an infix designator.
  • Fixed the URL path encoding
  • Fixed bug in lookahead handler with not properly encoding queries

• Code Changes

  • Fixed the overriding query respond to parameter
  • Added in Testing for the Panl Generator and refactored how it is being done.
  • Refactored PanlFields for the generator to output better comments and helpful information rather than more comments than necessary
  • General code cleanup and refactorings
  • Updated the look and feel for the Panl Simple Results Viewer Web App ( including images)
  • Modularised the JavaScript for common functions.

• Documentation update

  • Added in keyword search integration and 'search within results' integration notes
  • Changed the panl.form.query.respondto documentation to point to search rather than the previously defined q to reduce confusion
  • General spelling and grammatical mistake updates
  • Addition of new functionality and configuration properties pushing the book to be over 400 pages.

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1.2.0 - more like this (codename needy-phanton)

• Bug fixes

  • Fixed JavaScript in Single Page Search results in-built web app to take into account range facets
  • Fixed serving in-built panl testing URLs when run from the script

• Code changes

  • Retrieval of more facets functionality added:
    • Added in facet_limit JSON key for retrieving more facet results
    • Added in handler for retrieving more facets for a specific search field
  • Better output for testing URLs
  • Added Always on OR facets and panl.or.always.<lpse_code> property
  • Moved log4j out of the jar file so that user's con configure their own logging

• Breaking Changes - (which is OK as nobody is using it at the moment :) )

  • Changed the single page search URL binding from /panl-configuration/ to /panl-single-page/ as it makes more sense

• Documentation update

  • General spelling and grammatical mistake updates
  • Update to new functionality and configuration properties
  • Added in the pagination returned JSON Object implementation details
  • Added in URLs bound by the Panl server in the Appendices

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1.1.1 - the fly spray (codename grizzled-pebble)

• Bug fixes

  • Fixed 'OR' facet before and after URL values in the JSON response where a range facet has already been selected

• Code cleanup

  • Updated explanation for DATE Range and RANGE facets

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1.1.0 - the better update (codename broad-firefly)

• Added in empty FieldSet to return no documents

• Added in Single Search Page functionality

• Update Mechanical Pencils

  • Added in hierarchy for the Pencil Model example

• Dynamic range functionality - pulling actual values for the facet

• Suppress facet values for ranges, so that the user may only select from the range UI, and the individual range facet values do not appear

• Documentation update

  • New documentation for additional features and functionality
  • Fixed general spelling and grammar errors
  • Updated mechanical pencils introductory dataset explanations
  • Added in documentation for Fields
  • Panl cookbook

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1.0.0 - the initial release (codename bright-wildflower)

• Initial release with base functionality

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Additional Functionality In The Pipeline (possibly :)

1. Additional support for Solr field types (Low priority)
   • Some will be implemented, some will probably be ignored (anything geospatial is probably not going to be included).
2. Single search page
   • [Released in version 9-1.1.0]
   • Being able to have a search landing page with all options available, with the ability to implement a single search page.
3. Hierarchical facets based on value (Low priority)
   • Being able to only show facets if another facet has been selected with a specific value. This is probably not the best feature to include as it ties the configuration with the data values, which may change over time.
4. Facet value replacement (Low priority)
   • Being able to replace values for specific values of any facet, although this feature would tie the dataset and the Panl configuration together more tightly than I would like. This will probably be a simple lookup table for word replacement, however would also need to be parsed on the way out of the Solr results as well.
5. 'More Like This' functionality (Medium priority)
   1. The ability to return 'more like this' results on a certain field, or FieldSets.
6. Dynamic range functionality
   • [Released in version 9-1.1.0]
   • Dynamically generate the minimum and maximum value for a range for a facet value.
7. Suppress range values
   • [Released in version 9-1.1.0]
   • For a RANGE facet, provide a configuration option to suppress the values that appear in the range as separate values.
8. Returning more facets for a specific facet field
   • [Released in version 9-1.2.0]
   • By default, the facet limit is set to be 100 facet values per facet, in the instance where the returned number of facets are greater than this value, the facets will be truncated. The Panl server should be able to return the remaining facets with a simple query, without returning any documents with it. This should be done on an individual facet and possibly have pagination.
9. Default empty FieldSet
   • [Released in version 9-1.1.0]
   • In addition to the 'default' FieldSet, add another FieldSet always named 'empty' which will return no fields (this links in with the ' Returning more facets for a specific facet field' and 'Single search page' items).
10. Internationalisation
    • [Released in version 9-1.1.0]
    • Floating point digits in particular suffer from using a full stop/period as a decimal place i.e. in the UK, a digit would be formatted e.g. 12,345,678.90, whilst most other European countries use a comma for the decimal place e.g. 12.345.678,90.
11. DATE Range facet update (Medium priority)
    • As an extension to internationalisation, the DATE Range facet could do with an update to ensure that the SEO URL is better suited to international uses. For example, this facet will respond to <range_identifier><value><range_type> - e.g. 'previous 30 days' however for other languages this is not the most suitable - e.g. in French it might be '30 jours précédents' as in <value><range_type><range_identifier>.
12. Integrated typeahead
    • [Released in version 9-2.0.0]
    • An example and implementation of type-ahead in the search results, this is not the suggester feature of the Solr server, rather a way to return documents with no facet information - just the documents. In effect this is the opposite of the 'empty' CaFUP - where documents are returned, just no facets, just relying on the Solr index.
13. Specific Solr field search query options (Medium priority)
    • [Released in version 9-2.0.0]
    • Add in an LPSE code to be able to search on a specific field, fields, or all fields, rather than the default search field, or search for individual fields.
14. Panl configuration editor (Low priority)
    • A GUI to edit (and validate) the Panl configuration files making it easier for a developer to get the configuration correct.
15. Arbitrary Solr query addition (Low priority)
    • Being able to add arbitrary Solr query params to individual collections - there is some Solr functionality which does not require any configuration parameters to be surfaced through the Panl server.
16. Update RANGE LPSE URL encoding
    • [Released in version 9-2.0.0]
    • Changing the RANGE LPSE URL from <lpse_code>(+/-)<lpse_code> to just < lpse_code>(+/-) - not really sure why this wasn't implemented in the initial release, will require backwards compatibility checking.
17. Always on OR facets
    • [Released in version 9-1.2.0]
    • OR facets will not be presented if another facet has been selected, this will force the facet to always be returned, this will allow the results to continue to grow.
18. Arbitrary DATE Ranges (Low priority)
    • Being able to have a way of having arbitrary ranges - e.g. from 3 to 6 months, or 3 to 6 months before - this almost ties in with the DATE Range facet update element.
19. Arbitrary Separated Values for OR facets
    • [Released in version 9-2.0.0]
    • Rather than having a prefix and/or suffix added to the Solr field value for each OR facet, being able to have a separator character (or characters) between the values. E.g. for the following example URL:
    • /Manufactured By The Caran d'Ache Company/Manufactured By The BIC Company/bb/
    • Should be able to be configured to be displayed as (or something along the lines of it):
    • /Manufactured By The Caran d'Ache, or BIC Company/b/
20. Update command line help text (Low priority)
    • Currently, the full help is displayed, which should only be done if no command is given. If a command is given, then only the help for that command should be printed out.
21. Arbitrary Separated Values for REGULAR multi-valued facets
    • [Released in version 9-2.0.0]
    • Rather than having a prefix and/or suffix added to the Solr field value for each REGULAR multi-valued facet, being able to have a separator character (or characters) between the values. E.g. for the following example URL:
    • /Black/Blue/WW/
    • Should be able to be configured to be displayed as (or something along the lines of it):
    • /Colours:Black,Blue/W/
22. BOOLEAN Facet set checkbox value (Low priority)
    • [Released in version 9-2.0.0]
    • Have an additional option for whether a BOOLEAN facet should be displayed as a checkbox, the property either doesn't exist or is set to true or false depending on which of the boolean values should be highlighted.
    • Thought is required as to whether this becomes an additional key in the available facets, and whether it should be permanent.
23. Multiple lookaheads based on query fields (Low priority)
    • This has a dependency on the 'Specific Solr field search query options' and would allow a lookahead to work only on specific fields. Although this is probably better as database driven…
24. JSON configuration file (Low priority)
    • Change the panl.properties file to be JSON based, this makes the parsing a little more difficult, but also easier.
    • Step one would be to generate the properties files in memory from the JSON configuration, then completely replace them.
    • Whilst
    • there are some niceties with JSON files, there are also some parts which make it worse (especially around commenting).
25. Cached OR Facet Values (Medium Priority)
    • Where the user wants to display an OR facet, and also wants to display the original counts (which will display as zero if any of the OR facets are displayed)
26. Panl generator - attempt to keep existing field LPSE codes (Low Priority)
    • For any LPSE codes which are randomly assigned by the generator, keep a lookup map of the codes and attempt to keep this assignment on re-generation.
27. Update the Explainer (Low Priority)
    • The explainer has languished and only returns simple lists of strings this should return JSON and be able to be inspected.
28. Specific Search Field Boosting (Low Priority)
    • [Released in version 9-2.0.0]
    • Being able to boost specific fields when searching on Specific Solr fields this is done on a Panl collection basis.
29. DATE Range and RANGE value replacement (Low Priority)
    • For both of the range facets, it would be nice to be able to configure to replace the URL with a Panl query, for example: The DATE Range Facet could have a replacement of 'Coming Soon' which would be translate to 'Next 3 months' and the RANGE Facet could have a replacement of 'Inexpensive' to translate to 'From 5 to 10 dollars'
30. Unless property (Medium Priority)
    • [Released in version 9-2.0.0]
    • Display this facet 'unless' another facet within the list of 'unless' facets is selected.
    • This is the opposite of the panl.when.<lpse_code>.
31. Remove unneeded Solr JSON Response keys (Low Priority)
    • Solr returns JSON keys that are duplicated in the Panl response (think facet_counts) which are duplicated in the values array for Panl.
    • Provide a property which removes the unneeded/duplicate keys - need to decide whether this is server level, or CaFUP level.