Elasticsearch提供單文檔API和多文檔API,其中API調(diào)用分別針對(duì)單個(gè)文檔和多個(gè)文檔。
當(dāng)使用特定映射對(duì)相應(yīng)索引發(fā)出請(qǐng)求時(shí),它有助于在索引中添加或更新JSON文檔。 例如,以下請(qǐng)求將JSON對(duì)象添加到索引學(xué)校和學(xué)校映射下。
POST http://localhost:9200/schools/school/4
請(qǐng)求正文
{
"name":"City School", "description":"ICSE", "street":"West End", "city":"Meerut",
"state":"UP", "zip":"250002", "location":[28.9926174, 77.692485], "fees":3500,
"tags":["fully computerized"], "rating":"4.5"
}
響應(yīng)
{
"_index":"schools", "_type":"school", "_id":"4", "_version":1,
"_shards":{"total":2, "successful":1,"failed":0}, "created":true
}
當(dāng)請(qǐng)求將JSON對(duì)象添加到特定索引時(shí),如果該索引不存在,那么此API會(huì)自動(dòng)創(chuàng)建該索引以及該特定JSON對(duì)象的基礎(chǔ)映射。 可以通過將以下參數(shù)的值更改為false
來(lái)禁用此功能,這個(gè)值是存在于elasticsearch.yml
文件中,打開elasticsearch.yml
文件設(shè)置如下 。
action.auto_create_index:false
index.mapper.dynamic:false
還可以限制自動(dòng)創(chuàng)建索引,其中通過更改以下參數(shù)的值只允許指定模式的索引名稱 -
action.auto_create_index:+acc*,-bank*
(其中+
表示允許, -
表示不允許)
Elasticsearch還提供版本控制功能。我們可以使用版本查詢參數(shù)指定特定文檔的版本。 例如,
POST http://localhost:9200/schools/school/1?version = 1
請(qǐng)求正文
{
"name":"Central School", "description":"CBSE Affiliation", "street":"Nagan",
"city":"paprola", "state":"HP", "zip":"176115", "location":[31.8955385, 76.8380405],
"fees":2200, "tags":["Senior Secondary", "beautiful campus"], "rating":"3.3"
}
響應(yīng)內(nèi)容
{
"_index":"schools", "_type":"school", "_id":"1", "_version":2,
"_shards":{"total":2, "successful":1,"failed":0}, "created":false
}
有兩種最重要的版本控制類型: 內(nèi)部版本控制是以1
開頭的默認(rèn)版本,每次更新都會(huì)增加,包括刪除。版本號(hào)可以在外部設(shè)置。要啟用此功能,我們需要將version_type
設(shè)置為external
。
版本控制是一個(gè)實(shí)時(shí)過程,它不受實(shí)時(shí)搜索操作的影響。
操作類型用于強(qiáng)制創(chuàng)建操作,這有助于避免覆蓋現(xiàn)有文檔。
POST http://localhost:9200/tutorials/chapter/1?op_type = create
請(qǐng)求正文
{
"Text":"this is chapter one"
}
響應(yīng)內(nèi)容
{
"_index":"tutorials", "_type":"chapter", "_id":"1", "_version":1,
"_shards":{"total":2, "successful":1, "failed":0}, "created":true
}
當(dāng)在索引操作中未指定ID
時(shí),Elasticsearch自動(dòng)為文檔生成ID
。
可以通過在父URL查詢參數(shù)中傳遞父文檔的ID來(lái)定義任何文檔的父級(jí)。
POST http://localhost:9200/tutorials/article/1?parent = 1
請(qǐng)求正文
{
"Text":"This is article 1 of chapter 1"
}
注意 - 如果在執(zhí)行此示例時(shí)遇到異常,請(qǐng)通過在索引中添加以下內(nèi)容來(lái)重新創(chuàng)建索引。
{ "mappings": { "chapter": {}, "article": { "_parent": { "type": "chapter" } } } }
默認(rèn)情況下,索引操作將在主分片上最多等待1分鐘,超過后就會(huì)失敗并響應(yīng)錯(cuò)誤。 可以通過將值傳遞給timeout
參數(shù)來(lái)顯式更改這個(gè)超時(shí)值。
POST http://localhost:9200/tutorials/chapter/2?timeout = 3m
請(qǐng)求正文
{
"Text":"This is chapter 2 waiting for primary shard for 3 minutes"
}
API通過對(duì)特定文檔執(zhí)行get
請(qǐng)求來(lái)幫助提取JSON對(duì)象。 例如,
GET http://localhost:9200/schools/school/1
響應(yīng)
{
"_index":"schools", "_type":"school", "_id":"1", "_version":2,
"found":true, "_source":{
"name":"Central School", "description":"CBSE Affiliation",
"street":"Nagan", "city":"paprola", "state":"HP", "zip":"176115",
"location":[31.8955385,76.8380405], "fees":2200,
"tags":["Senior Secondary", "beautiful campus"], "rating":"3.3"
}
}
_all
,以便Elasticsearch可以在每種類型中搜索該文檔ID
,并且它將返回第一個(gè)匹配的文檔。GET http://localhost:9200/schools/school/1?fields = name,fees
響應(yīng)
……………………..
"fields":{
"name":["Central School"], "fees":[2200]
}
……………………..
還可以通過在get
請(qǐng)求中添加_source
字段來(lái)獲取結(jié)果中的源部分。
GET http://localhost:9200/schools/school/1/_source
響應(yīng)
{
"name":"Central School", "description":"CBSE Afiliation", "street":"Nagan",
"city":"paprola", "state":"HP", "zip":"176115", "location":[31.8955385, 76.8380405],
"fees":2200, "tags":["Senior Secondary", "beatiful campus"], "rating":"3.3"
}
還可以在通過將 refresh
參數(shù)設(shè)置為true
進(jìn)行get
操作之前刷新碎片。
可以通過向Elasticsearch發(fā)送HTTP DELETE
請(qǐng)求來(lái)刪除指定的索引,映射或文檔。 例如,
DELETE http://localhost:9200/schools/school/4
響應(yīng)
{
"found":true, "_index":"schools", "_type":"school", "_id":"4", "_version":2,
"_shards":{"total":2, "successful":1, "failed":0}
}
refresh
)和超時(shí)(timeout
)選項(xiàng)。腳本用于執(zhí)行此操作,版本控制用于確保在獲取和重建索引期間沒有發(fā)生更新。 例如,使用下面腳本更新學(xué)校的費(fèi)用 -
POST http://localhost:9200/schools_gov/school/1/_update
請(qǐng)求正文
{
"script":{
"inline": "ctx._source.fees+ = inc", "params":{
"inc": 500
}
}
}
響應(yīng)結(jié)果
{
"_index":"schools_gov", "_type":"school", "_id":"1", "_version":2,
"_shards":{"total":2, "successful":1, "failed":0}
}
注意 - 如果獲取腳本異常,建議在
elastcisearch.yml
中添加以下行
script.inline: on
script.indexed: on
可以通過向更新的文檔發(fā)送獲取請(qǐng)求來(lái)檢查更新。
GET http://localhost:9200/schools_gov/school/1
它具有相同的功能,如GET API
,但此get
請(qǐng)求可以返回多個(gè)文檔。使用doc
數(shù)組來(lái)指定需要提取的所有文檔的索引,類型和ID。
POST http://localhost:9200/_mget
請(qǐng)求正文
{
"docs":[
{
"_index": "schools", "_type": "school", "_id": "1"
},
{
"_index":"schools_gev", "_type":"school", "_id": "2"
}
]
}
響應(yīng)結(jié)果
{
"docs":[
{
"_index":"schools", "_type":"school", "_id":"1",
"_version":1, "found":true, "_source":{
"name":"Central School", "description":"CBSE Afiliation",
"street":"Nagan", "city":"paprola", "state":"HP", "zip":"176115",
"location":[31.8955385,76.8380405], "fees":2000,
"tags":["Senior Secondary", "beatiful campus"], "rating":"3.5"
}
},
{
"_index":"schools_gev", "_type":"school", "_id":"2", "error":{
"root_cause":[{
"type":"index_not_found_exception", "reason":"no such index",
"index":"schools_gev"
}],
"type":"index_not_found_exception", "reason":"no such index",
"index":"schools_gev"
}
}
]
}
此API用于通過在單個(gè)請(qǐng)求中進(jìn)行多個(gè)索引/刪除操作來(lái)批量上傳或刪除JSON對(duì)象。 需要添加“_bulk
”關(guān)鍵字來(lái)調(diào)用此API。此API的示例已在Elasticsearch填充文章中執(zhí)行。所有其他功能與GET API相同。