/elasticsearch-river-web

Web Crawler for Elasticsearch

Primary LanguageJavaApache License 2.0Apache-2.0

(River Web does not sync up with the latest elasticsearch. Fess is Enterprise Search Server and contains the same features as River Web. See Fess)

Elasticsearch River Web

Overview

Elasticsearch River Web is a web crawler application for Elasticsearch. This application provides a feature to crawl web sites and extract the content by CSS Query. (As of version 1.5, River Web is not Elasticsearch plugin)

If you want to use Full Text Search Server, please see Fess.

Version

River Web Tested on ES Download
master 2.4.X Snapshot
2.4.0 2.4.0 Download
2.0.2 2.3.1 Download
2.0.1 2.2.0 Download
2.0.0 2.1.2 Download

For old version, see README_ver1.md or README_ver1.5.md.

Issues/Questions

Please file an issue. (Japanese forum is here.)

Installation

Install River Web

Zip File

$ unzip elasticsearch-river-web-[VERSION].zip

Tar.GZ File

$ tar zxvf elasticsearch-river-web-[VERSION].tar.gz

Usage

Create Index To Store Crawl Data

An index for storing crawl data is needed before starting River Web. For example, to store data to "webindex/my_web", create it as below:

$ curl -XPUT 'localhost:9200/webindex' -d '
{  
  "settings":{  
    "index":{  
      "refresh_interval":"1s",
      "number_of_shards":"10",
      "number_of_replicas" : "0"
    }
  },
  "mappings":{  
    "my_web":{  
      "properties":{  
        "url":{  
          "type":"string",
          "index":"not_analyzed"
        },
        "method":{  
          "type":"string",
          "index":"not_analyzed"
        },
        "charSet":{  
          "type":"string",
          "index":"not_analyzed"
        },
        "mimeType":{  
          "type":"string",
          "index":"not_analyzed"
        }
      }
    }
  }
}'

Feel free to add any properties other than the above if you need them.

Register Crawl Config Data

A crawling configuration is created by registering a document to .river_web index as below. This example crawls sites of http://www.codelibs.org/ and http://fess.codelibs.org/.

$ curl -XPUT 'localhost:9200/.river_web/config/my_web' -d '{
    "index" : "webindex",
    "type" : "my_web",
    "urls" : ["http://www.codelibs.org/", "http://fess.codelibs.org/"],
    "include_urls" : ["http://www.codelibs.org/.*", "http://fess.codelibs.org/.*"],
    "max_depth" : 3,
    "max_access_count" : 100,
    "num_of_thread" : 5,
    "interval" : 1000,
    "target" : [
      {
        "pattern" : {
          "url" : "http://www.codelibs.org/.*",
          "mimeType" : "text/html"
        },
        "properties" : {
          "title" : {
            "text" : "title"
          },
          "body" : {
            "text" : "body"
          },
          "bodyAsHtml" : {
            "html" : "body"
          },
          "projects" : {
            "text" : "ul.nav-list li a",
            "isArray" : true
          }
        }
      },
      {
        "pattern" : {
          "url" : "http://fess.codelibs.org/.*",
          "mimeType" : "text/html"
        },
        "properties" : {
          "title" : {
            "text" : "title"
          },
          "body" : {
            "text" : "body",
            "trimSpaces" : true
          },
          "menus" : {
            "text" : "ul.nav-list li a",
            "isArray" : true
          }
        }
      }
    ]
}'

The configuration is:

Property Type Description
index string Stored index name.
type string Stored type name.
urls array Start point of URL for crawling.
include_urls array White list of URL for crawling.
exclude_urls array Black list of URL for crawling.
max_depth int Depth of crawling documents.
max_access_count int The number of crawling documents.
num_of_thread int The number of crawler threads.
interval int Interval time (ms) to crawl documents.
incremental boolean Incremental crawling.
overwrite boolean Delete documents of old duplicated url.
user_agent string User-agent name when crawling.
robots_txt boolean If you want to ignore robots.txt, false.
authentications object Specify BASIC/DIGEST/NTLM authentication info.
target.urlPattern string URL pattern to extract contents by CSS Query.
target.properties.name string "name" is used as a property name in the index.
target.properties.name.text string CSS Query for the property value.
target.properties.name.html string CSS Query for the property value.
target.properties.name.script string Rewrite the property value by Script(Groovy).

Start Crawler

./bin/riverweb --config-id [config doc id] --cluster-name [Elasticsearch Cluster Name] --cleanup

For example,

./bin/riverweb --config-id my_web --cluster-name elasticsearch --cleanup

Unregister Crawl Config Data

If you want to stop the crawler, kill the crawler process and then delete the config document as below:

$ curl -XDELETE 'localhost:9200/.river_web/config/my_web'

Examples

Full Text Search for Your site (ex. http://fess.codelibs.org/)

$ curl -XPUT 'localhost:9200/.river_web/fess/fess_site' -d '{
    "index" : "webindex",
    "type" : "fess_site",
    "urls" : ["http://fess.codelibs.org/"],
    "include_urls" : ["http://fess.codelibs.org/.*"],
    "max_depth" : 3,
    "max_access_count" : 1000,
    "num_of_thread" : 5,
    "interval" : 1000,
    "target" : [
      {
        "pattern" : {
            "url" : "http://fess.codelibs.org/.*",
            "mimeType" : "text/html"
        },
        "properties" : {
            "title" : {
                "text" : "title"
            },
            "body" : {
                "text" : "body",
                "trimSpaces" : true
            }
        }
      }
    ]
}'

Aggregate a title/content from news.yahoo.com

$ curl -XPUT 'localhost:9200/.river_web/config/yahoo_site' -d '{
    "index" : "webindex",
    "type" : "my_web",
    "urls" : ["http://news.yahoo.com/"],
    "include_urls" : ["http://news.yahoo.com/.*"],
    "max_depth" : 1,
    "max_access_count" : 10,
    "num_of_thread" : 3,
    "interval" : 3000,
    "user_agent" : "Mozilla/5.0 (Windows NT 6.3; Trident/7.0; rv:11.0) like Gecko",
    "target" : [
      {
        "pattern" : {
          "url" : "http://news.yahoo.com/video/.*html",
          "mimeType" : "text/html"
        },
        "properties" : {
          "title" : {
            "text" : "title"
          }
        }
      },
      {
        "pattern" : {
          "url" : "http://news.yahoo.com/.*html",
          "mimeType" : "text/html"
        },
        "properties" : {
          "title" : {
            "text" : "h1.headline"
          },
          "content" : {
            "text" : "section#mediacontentstory p"
          }
        }
      }
    ]
}'

(if news.yahoo.com is updated, the above example needs to be updated.)

Others

BASIC/DIGEST/NTLM authentication

River Web supports BASIC/DIGEST/NTLM authentication. Set authentications object.

...
"num_of_thread" : 5,
"interval" : 1000,
"authentications":[
  {
    "scope": {
      "scheme":"BASIC"
    },
    "credentials": {
      "username":"testuser",
      "password":"secret"
    }
  }],
"target" : [
...

The configuration is:

Property Type Description
authentications.scope.scheme string BASIC, DIGEST or NTLM
authentications.scope.host string (Optional)Target hostname.
authentications.scope.port int (Optional)Port number.
authentications.scope.realm string (Optional)Realm name.
authentications.credentials.username string Username.
authentications.credentials.password string Password.
authentications.credentials.workstation string (Optional)Workstation for NTLM.
authentications.credentials.domain string (Optional)Domain for NTLM.

For example, if you want to use an user in ActiveDirectory, the configuration is below:

"authentications":[
  {
    "scope": {
      "scheme":"NTLM"
    },
    "credentials": {
      "domain":"your.ad.domain",
      "username":"taro",
      "password":"himitsu"
    }
  }],

Use attachment type

River Web supports attachment type. For example, create a mapping with attachment type:

curl -XPUT "localhost:9200/web/test/_mapping?pretty" -d '{
  "test" : {
    "properties" : {
...
      "my_attachment" : {
          "type" : "attachment",
          "fields" : {
            "file" : { "index" : "no" },
            "title" : { "store" : "yes" },
            "date" : { "store" : "yes" },
            "author" : { "store" : "yes" },
            "keywords" : { "store" : "yes" },
            "content_type" : { "store" : "yes" },
            "content_length" : { "store" : "yes" }
          }
      }
...

and then start your river. In "properties" object, when a value of "type" is "attachment", the crawled url is stored as base64-encoded data.

curl -XPUT localhost:9200/.river_web/config/2 -d '{
      "index" : "web",
      "type" : "data",
      "urls" : "http://...",
...
      "target" : [
...
        {
          "settings" : {
            "html" : false
          },
          "pattern" : {
            "url" : "http://.../.*"
          },
          "properties" : {
            "my_attachment" : {
              "type" : "attachment"
            }
          }
        }
      ]
...

Use Multibyte Characters

An example in Japanese environment is below. First, put some configuration file into conf directory of Elasticsearch.

$ cd $ES_HOME/conf    # ex. /etc/elasticsearch if using rpm package
$ sudo wget https://raw.github.com/codelibs/fess-server/master/src/tomcat/solr/core1/conf/mapping_ja.txt
$ sudo wget http://svn.apache.org/repos/asf/lucene/dev/trunk/solr/example/solr/collection1/conf/lang/stopwords_ja.txt 

and then create "webindex" index with analyzers for Japanese. (If you want to use uni-gram, remove cjk_bigram in filter)

$ curl -XPUT "localhost:9200/webindex" -d '
{
  "settings" : {
    "analysis" : {
      "analyzer" : {
        "default" : {
          "type" : "custom",
          "char_filter" : ["mappingJa"],
          "tokenizer" : "standard",
          "filter" : ["word_delimiter", "lowercase", "cjk_width", "cjk_bigram"]
        }
      },
      "char_filter" : {
        "mappingJa": {
          "type" : "mapping",
          "mappings_path" : "mapping_ja.txt"
        }
      },
      "filter" : {
        "stopJa" : {
          "type" : "stop",
          "stopwords_path" : "stopwords_ja.txt"
        }
      }
    }
  }
}'

Rewrite a property value by Script

River Web allows you to rewrite crawled data by Java's ScriptEngine. "javascript" is available. In "properties" object, put "script" value to a property you want to rewrite.

...
        "properties" : {
...
          "flag" : {
            "text" : "body",
            "script" : "value.indexOf('Elasticsearch') > 0 ? 'yes' : 'no';"
          },

The above is, if a string value of body element in HTML contains "Elasticsearch", set "yes" to "flag" property.

Use HTTP proxy

Put "proxy" property in "crawl" property.

curl -XPUT 'localhost:9200/.river_web/config/my_web' -d '{
    "index" : "webindex",
    "type" : "my_web",
...
        "proxy" : {
          "host" : "proxy.server.com",
          "port" : 8080
        },

Specify next crawled urls when crawling

To set "isChildUrl" property to true, the property values is used as next crawled urls.

...
    "target" : [
      {
...
        "properties" : {
          "childUrl" : {
            "value" : ["http://fess.codelibs.org/","http://fess.codelibs.org/ja/"],
            "isArray" : true,
            "isChildUrl" : true
          },

Intercept start/execute/finish/close actions

You can insert your script to Executing Crawler(execute)/Finished Crawler(finish). To insert scripts, put "script" property as below:

curl -XPUT 'localhost:9200/.river_web/config/my_web' -d '{
    "script":{
      "execute":"your script...",
      "finish":"your script...",
    },
    ...

FAQ

What does "No scraping rule." mean?

In a river setting, "url" is starting urls to crawl a site, "include_urls" filters urls whether are crawled or not, and "target.pattern.url" is a rule to store extracted web data. If a crawling url does not match "target.pattern.url", you would see the message. Therefore, it means the crawled url does not have an extraction rule.

How to extract an attribute of meta tag

For example, if you want to grab a content of description's meta tag, the configuration is below:

...
"target" : [
...
  "properties" : {
...
    "meta" : {
      "attr" : "meta[name=description]",
      "args" : [ "content" ]
    },

Incremental crawling dose not work?

"url" field needs to be "not_analyzed" in a mapping of your stored index. See Create Index To Store Crawl Data.

Where is crawled data stored?

crawled data are stored to ".s2robot" index during cralwing, data extracted from them are stored to your index specified by a river setting, and then data in "robot" index are removed when the crawler is finished.

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