In ropensci/solrium: General Purpose R Interface to 'Solr'

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Solr search

A general purpose R interface to Apache Solr

Solr info

• Solr home page
• Highlighting help
• Faceting help
• Install and Setup SOLR in OSX, including running Solr

Installation

Stable version from CRAN

install.packages("solrium")

Or the development version from GitHub

install.packages("devtools")
devtools::install_github("ropensci/solrium")

Load

library("solrium")

Setup connection

You can setup for a remote Solr instance or on your local machine.

(conn <- SolrClient$new(host = "api.plos.org", path = "search", port = NULL))

Rundown

solr_search() only returns the docs element of a Solr response body. If docs is all you need, then this function will do the job. If you need facet data only, or mlt data only, see the appropriate functions for each of those below. Another function, solr_all() has a similar interface in terms of parameter as solr_search(), but returns all parts of the response body, including, facets, mlt, groups, stats, etc. as long as you request those.

Search docs

solr_search() returns only docs. A basic search:

conn$search(params = list(q = '*:*', rows = 2, fl = 'id'))

Search in specific fields with :

Search for word ecology in title and cell in the body

conn$search(params = list(q = 'title:"ecology" AND body:"cell"', fl = 'title', rows = 5))

Wildcards

Search for word that starts with "cell" in the title field

conn$search(params = list(q = 'title:"cell*"', fl = 'title', rows = 5))

Proximity search

Search for words "sports" and "alcohol" within four words of each other

conn$search(params = list(q = 'everything:"stem cell"~7', fl = 'title', rows = 3))

Range searches

Search for articles with Twitter count between 5 and 10

conn$search(params = list(q = '*:*', fl = c('alm_twitterCount', 'id'), fq = 'alm_twitterCount:[5 TO 50]', rows = 10))

Boosts

Assign higher boost to title matches than to body matches (compare the two calls)

conn$search(params = list(q = 'title:"cell" abstract:"science"', fl = 'title', rows = 3))

conn$search(params = list(q = 'title:"cell"^1.5 AND abstract:"science"', fl = 'title', rows = 3))

Search all

solr_all() differs from solr_search() in that it allows specifying facets, mlt, groups, stats, etc, and returns all of those. It defaults to parsetype = "list" and wt="json", whereas solr_search() defaults to parsetype = "df" and wt="csv". solr_all() returns by default a list, whereas solr_search() by default returns a data.frame.

A basic search, just docs output

conn$all(params = list(q = '*:*', rows = 2, fl = 'id'))

Get docs, mlt, and stats output

conn$all(params = list(q = 'ecology', rows = 2, fl = 'id', mlt = 'true', mlt.count = 2, mlt.fl = 'abstract', stats = 'true', stats.field = 'counter_total_all'))

Facet

conn$facet(params = list(q = '*:*', facet.field = 'journal', facet.query = c('cell', 'bird')))

Highlight

conn$highlight(params = list(q = 'alcohol', hl.fl = 'abstract', rows = 2))

Stats

out <- conn$stats(params = list(q = 'ecology', stats.field = c('counter_total_all', 'alm_twitterCount'), stats.facet = c('journal', 'volume')))

out$data

out$facet

More like this

solr_mlt is a function to return similar documents to the one

out <- conn$mlt(params = list(q = 'title:"ecology" AND body:"cell"', mlt.fl = 'title', mlt.mindf = 1, mlt.mintf = 1, fl = 'counter_total_all', rows = 5))
out$docs

out$mlt

Groups

solr_groups() is a function to return similar documents to the one

conn$group(params = list(q = 'ecology', group.field = 'journal', group.limit = 1, fl = c('id', 'alm_twitterCount')))

Parsing

solr_parse() is a general purpose parser function with extension methods for parsing outputs from functions in solr. solr_parse() is used internally within functions to do parsing after retrieving data from the server. You can optionally get back raw json, xml, or csv with the raw=TRUE, and then parse afterwards with solr_parse().

For example:

(out <- conn$highlight(params = list(q = 'alcohol', hl.fl = 'abstract', rows = 2), raw = TRUE))

Then parse

solr_parse(out, 'df')

Please report any issues or bugs.

ropensci/solrium documentation built on Sept. 12, 2022, 3:01 p.m.