Hui 辉 Build Status Hex pm Coverage Status

Hui 辉 (“shine” in Chinese) is a Solr client and library for Elixir.

Usage

Hui enables Solr querying, updating and other forms of interaction in Elixir or Phoenix applications. Typical Solr data can be contained within a core (index) held on a single server or a data collection in distributed server architecture (cloud).

Example - searching


  Hui.q("scott") # keywords search
  Hui.q(q: "loch", rows: 5) # arbitrary keyword list
  
  # with query structs
  alias Hui.Query.{Standard,DisMax,Common,Facet,FacetRange,Suggest,MoreLikeThis,Highlight}

  Hui.q([%Standard{q: "author:I*"}, %Facet{field: ["cat", "author_str"], mincount: 1}])

  # `:library` is a URL reference key - see below
  Hui.search(:library, [%Standard{q: "loch"}, %Common{fq: ["type:illustration", "format:image/jpeg"]}])

  # Suggester query
  suggest_query = %Suggest{q: "ha", count: 10, dictionary: ["name_infix", "ln_prefix", "fn_prefix"]}
  Hui.suggest(:library, suggest_query)

  # DisMax and SolrCloud query
  x = %DisMax{q: "market", qf: "description^2.3 title", mm: "2<-25% 9<-3", pf: "title", ps: 1, qs: 3}
  y = %Common{collection: "library,commons", rows: 10, distrib: true, "shards.tolerant": true, "shards.info": true}
  Hui.search(:library, [x, y])

  # with MoreLikeThis
  z = %MoreLikeThis{fl: "manu,cat", mindf: 10, mintf: 200, "match.include": true, count: 10}
  Hui.search(:library, [x, y, z])

  # with faceting
  z = %Facet{field: ["cat", "author_str"], mincount: 1}
  Hui.search(:library, [x, y, z])

  # with results highlighting
  z = %Highlight{fl: "features", usePhraseHighlighter: true, fragsize: 250, snippets: 3 } 
  Hui.search(:library, [x, y, z])

  # more elaborated faceting query
  range1 = %FacetRange{range: "price", start: 0, end: 100, gap: 10, per_field: true}
  range2 = %FacetRange{range: "popularity", start: 0, end: 5, gap: 1, per_field: true}
  z = %Facet{field: ["cat", "author_str"], mincount: 1, range: [range1, range2]}
  Hui.search(:library, [x, y, z])

  # the above spawns a request with the following query string
  #
  # q=...&
  # f.price.facet.range.end=100&
  # f.price.facet.range.gap=10&facet.range=price&
  # f.price.facet.range.start=0&
  # f.popularity.facet.range.end=5&
  # f.popularity.facet.range.gap=1&
  # facet.range=popularity&
  # f.popularity.facet.range.start=0

  # convenience functions
  Hui.search(:library, "apache documentation", 1, 5, "stream_content_type_str:text/html", ["subject"])
  Hui.suggest(:autocomplete, "ha", 5, ["name_infix", "ln_prefix", "fn_prefix"], "1939")

The q examples send requests to a :default configured endpoint (see Configuration below). Query parameters could be a string, a Keyword list or built-in query Structs providing a structured way for invoking the comprehensive and powerful features of Solr.

Queries may also be issued to other endpoints and request handlers:

  # URL binary string
  Hui.search("http://localhost:8983/solr/collection", q: "loch")

  # URL key referring to an endpoint in configuration - see "Configuration"
  url = :library
  Hui.search(url, q: "edinburgh", rows: 10)

  # URL in a struct
  url = %Hui.URL{url: "http://localhost:8983/solr/collection", handler: "suggest"}
  Hui.search(url, %Hui.Query.Suggest{q: "el", dictionary: "mySuggester"})
  # spawns => http://http://localhost:8983/solr/collection/suggest?suggest=true&suggest.dictionary=mySuggester&suggest.q=el

See the API reference and Solr reference guide for more details on available search parameters.

Example - updating

Hui provides functions to add, update and delete Solr documents, as well as optimised search indexes.

  # Specify an update handler endpoint for JSON-formatted update
  headers = [{"Content-type", "application/json"}]
  url = %Hui.URL{url: "http://localhost:8983/solr/collection", handler: "update", headers: headers}

  # Solr documents
  doc1 = %{
    "actors" => ["Ingrid Bergman", "Liv Ullmann", "Lena Nyman", "Halvar Björk"],
    "desc" => "A married daughter who longs for her mother's love is visited by the latter, a successful concert pianist.",
    "directed_by" => ["Ingmar Bergman"],
    "genre" => ["Drama", "Music"],
    "id" => "tt0077711",
    "initial_release_date" => "1978-10-08",
    "name" => "Autumn Sonata"
  }
  doc2 = %{
    "actors" => ["Bibi Andersson", "Liv Ullmann", "Margaretha Krook"],
    "desc" => "A nurse is put in charge of a mute actress and finds that their personas are melding together.",
    "directed_by" => ["Ingmar Bergman"],
    "genre" => ["Drama", "Thriller"],
    "id" => "tt0060827",
    "initial_release_date" => "1967-09-21",
    "name" => "Persona"
  }

  # Add the docs and commit them to the index immediately
  Hui.update(url, [doc1, doc2])

  # Send documents to another pre-configured endpoint
  Hui.update(:updater, [doc1, doc2])

  Hui.delete(url, "tt0077711") # delete one doc
  Hui.delete(url, ["tt0077711", "tt0060827"]) # delete a list of docs
  Hui.delete_by_query(url, ["genre:Drama", "name:Persona"]) # delete via filter queries

More advanced update requests can be issued using the Hui.Query.Update struct, as well as through any valid binary data encapsulating Solr documents and commands.

  # url, doc1, doc2 from the above example
  ...

  # Hui.Query.Update struct command for updating and committing the docs to Solr immediately

  alias Hui.Query.Update

  x = %Update{doc: [doc1, doc2], commit: true, waitSearcher: true}
  Hui.update(url, x)

  # Commits docs within 5 seconds
  x = %Update{doc: [doc1, doc2], commitWithin: 5000, overwrite: true}
  Hui.update(url, x)

  # Commit and optimise index
  Hui.update(url, %Update{commit: true, waitSearcher: true, optimize: true, maxSegments: 10})

  # Binary mode, e.g. delete a document via XML binary
  headers = [{"Content-type", "application/xml"}]
  url = %Hui.URL{url: "http://localhost:8983/solr/collection", handler: "update", headers: headers}
  Hui.update(url, "<delete><id>9780141981727</id></delete>")

See Solr reference for more details on update commands, data types and formats.

HTTP headers and options

HTTP headers and options can be specified via the Hui.URL.t/0 struct.

  # setting up a header and a 10s receiving connection timeout
  url = %Hui.URL{url: "..", headers: [{"accept", "application/json"}], options: [recv_timeout: 10000]}
  Hui.search(url, q: "solr rocks")

Headers and options for a specific endpoint may also be configured - see “Configuration”.

Software library

Hui modules and data structures can be used for building Solr application in Elixir and Phoenix.

The following struct modules provide an idiomatic and structured way for creating and encoding Solr parameters:

For example, multiple filters and facet fields can be specified using fq: ["field1", "field2"], field: ["field1", "field2"], gap: 10 Elixir codes.

“Per-field” faceting for multiple ranges and intervals can be specified in a succinct and unified way, e.g. gap instead of the long-winded f.[fieldname].facet.range.gap (per field) or facet.range.gap (single field). Per-field use case for a facet can be set via the per_field key - see below.

Hui includes a protocol (with implementation):

  • Hui.Encoder for encoding the query structs into binary (JSON format forthcoming)

A custom query struct may be developed by implementing the Encoder protocol.

  alias Hui.Query.{DisMax,Common,Facet,FacetRange}

  x = %DisMax{q: "loch"}
  y = %Common{fq: ["type:image/jpeg", "year:2001"], fl: "id,title", rows: 20}
  [x,y] |> Hui.Encoder.encode
  # -> "q=loch&fl=id%2Ctitle&fq=type%3Aimage%2Fjpeg&fq=year%3A2001&rows=20"

  x = %Facet{field: ["type", "year", "subject"], query: "edited:true"}
  x |> Hui.Encoder.encode
  # -> "facet=true&facet.field=type&facet.field=year&facet.field=subject&facet.query=edited%3Atrue"
  # there's no need to set "facet: true" as it is implied and a default setting in the struct

  # a unified way to specify per-field or singe-field range
  x = %FacetRange{range: "age", gap: 10, start: 0, end: 100}
  x |> Hui.Encoder.encode
  # -> "facet.range.end=100&facet.range.gap=10&facet.range=age&facet.range.start=0"

  x = %{x | per_field: true} # toggle per field faceting
  x |> Hui.Encoder.encode
  # -> "f.age.facet.range.end=100&f.age.facet.range.gap=10&facet.range=age&f.age.facet.range.start=0"

The Hui.Query.Update struct module enables various JSON-formatted update and grouped commands to be created.

  alias Hui.Query.Update
  alias Hui.Encoder

  # doc1, doc2 are Maps of Solr documents
  x = %Update{doc: [doc1, doc2], commit: true, commitWithin: 1000}
  x |> Encoder.encode
  # -> "{\"add\":{\"commitWithin\":1000,\"doc\":{...}},\"add\":{\"commitWithin\":1000,\"doc\":{...}},\"commit\":{}}"

  # Delete the documents by ID
  %Update{delete_id: ["tt1316540", "tt1650453"]} |> Encoder.encode
  # -> "{\"delete\":{\"id\":\"tt1316540\"},\"delete\":{\"id\":\"tt1650453\"}}"

The structs and their associated type spec also provide binding to and introspection of the available fields.

  iex> %Hui.Query.Facet{field: ["type", "year"], query: "year:[2000 TO NOW]"}
  %Hui.Query.Facet{
    contains: nil,
    "contains.ignoreCase": nil,
    "enum.cache.minDf": nil,
    excludeTerms: nil,
    exists: nil,
    facet: true,
    field: ["type", "year"],
    interval: nil,
    limit: nil,
    matches: nil,
    method: nil,
    mincount: nil,
    missing: nil,
    offset: nil,
    "overrequest.count": nil,
    "overrequest.ratio": nil,
    pivot: [],
    "pivot.mincount": nil,
    prefix: nil,
    query: "year:[2000 TO NOW]",
    range: nil,
    sort: nil,
    threads: nil
  }

Parsing Solr results

Hui returns Solr results as HTTP response struct containing the Solr response.

  {:ok,
   %Hui.Http{
    body: "...[Solr reponse]..",
    headers: [
      {"Content-Type", "application/json;charset=utf-8"},
      {"Content-Length", "4005"}
    ],
    method: :get,
    options: [], 
    status: 200,
    url: "http://localhost:8983/solr/gettingstarted/select?q=%2A"
   }
  }

JSON response is automatically parsed and decoded as Map. It is accessible via the body key.

  {status, resp} = Hui.q(solr_params)

  # getting a list of Solr documents (Map)
  solr_docs = resp.body["response"]["docs"]
  total_hits = resp.body["response"]["numFound"]

Note: other response formats such as XML, are currently being returned in raw text.

Installation

Hui is available in Hex, the package can be installed by adding hui to your list of dependencies in mix.exs:

  def deps do
    [
      {:hui, "~> 0.10.1"}
    ]
  end

Then run $ mix deps.get.

Documentation can be found at https://hexdocs.pm/hui.

Configuration

A default Solr endpoint may be specified in the application configuration as below:

  config :hui, :default,
    url: "http://localhost:8983/solr/gettingstarted",
    handler: "select", # optional
    headers: [{"accept", "application/json"}], # optional
    options: [recv_timeout: 10000] # optional

HTTP headers and options may also be configured.

See Hui.URL.default_url!/0.

Solr provides various request handlers for many purposes (search, autosuggest, spellcheck, indexing etc.). The handlers are configured in different custom or normative names in Solr configuration, e.g. “select” for search queries.

Additional endpoints and request handlers can be configured in Hui using arbitrary config keys (e.g. :suggester):

  config :hui, :suggester,
    url: "http://localhost:8983/solr/collection",
    handler: "suggest"

Use the config key in functions such as Hui.search/2, Hui.search/3 to send queries to the endpoint or retrieve URL settings from configuration e.g. Hui.URL.configured_url/1.

License

Hui is released under Apache 2 License. Check the LICENSE file for more information.