193 lines
3.6 KiB
Plaintext
193 lines
3.6 KiB
Plaintext
[[lang-python]]
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=== Python Language Plugin
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The Python language plugin enables the use of Python in Elasticsearch
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scripts, via the http://www.jython.org/[Jython] Java implementation of Python.
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[[lang-python-install]]
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[float]
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==== Installation
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This plugin can be installed using the plugin manager:
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[source,sh]
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----------------------------------------------------------------
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sudo bin/elasticsearch-plugin install lang-python
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----------------------------------------------------------------
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The plugin must be installed on every node in the cluster, and each node must
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be restarted after installation.
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[[lang-python-remove]]
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[float]
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==== Removal
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The plugin can be removed with the following command:
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[source,sh]
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----------------------------------------------------------------
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sudo bin/elasticsearch-plugin remove lang-python
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----------------------------------------------------------------
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The node must be stopped before removing the plugin.
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[[lang-python-usage]]
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==== Using Python in Elasticsearch
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Once the plugin has been installed, Python can be used at a scripting
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language by setting the `lang` parameter to `python`.
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Scripting is available in many APIs, but we will use an example with the
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`function_score` for demonstration purposes:
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[[lang-python-inline]]
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[float]
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=== Inline scripts
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WARNING: Enabling inline scripting on an unprotected Elasticsearch cluster is dangerous.
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See <<lang-python-file>> for a safer option.
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If you have enabled {ref}/modules-scripting.html#enable-dynamic-scripting[inline scripts],
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you can use Python as follows:
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[source,json]
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----
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DELETE test
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PUT test/doc/1
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{
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"num": 1.0
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}
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PUT test/doc/2
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{
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"num": 2.0
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}
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GET test/_search
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{
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"query": {
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"function_score": {
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"script_score": {
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"script": {
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"inline": "doc[\"num\"].value * factor",
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"lang": "python",
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"params": {
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"factor": 2
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}
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}
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}
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}
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}
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}
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----
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// AUTOSENSE
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[[lang-python-indexed]]
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[float]
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=== Indexed scripts
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WARNING: Enabling indexed scripting on an unprotected Elasticsearch cluster is dangerous.
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See <<lang-python-file>> for a safer option.
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If you have enabled {ref}/modules-scripting.html#enable-dynamic-scripting[indexed scripts],
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you can use Python as follows:
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[source,json]
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----
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DELETE test
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PUT test/doc/1
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{
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"num": 1.0
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}
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PUT test/doc/2
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{
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"num": 2.0
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}
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POST _scripts/python/my_script <1>
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{
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"script": "doc[\"num\"].value * factor"
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}
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GET test/_search
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{
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"query": {
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"function_score": {
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"script_score": {
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"script": {
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"id": "my_script", <2>
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"lang": "python",
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"params": {
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"factor": 2
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}
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}
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}
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}
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}
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}
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----
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// AUTOSENSE
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<1> We index the script under the id `my_script`.
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<2> The function score query retrieves the script with id `my_script`.
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[[lang-python-file]]
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[float]
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=== File scripts
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You can save your scripts to a file in the `config/scripts/` directory on
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every node. The `.py` file suffix identifies the script as containing
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Python:
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First, save this file as `config/scripts/my_script.py` on every node
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in the cluster:
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[source,python]
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----
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doc["num"].value * factor
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----
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then use the script as follows:
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[source,json]
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----
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DELETE test
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PUT test/doc/1
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{
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"num": 1.0
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}
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PUT test/doc/2
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{
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"num": 2.0
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}
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GET test/_search
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{
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"query": {
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"function_score": {
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"script_score": {
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"script": {
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"file": "my_script", <1>
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"lang": "python",
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"params": {
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"factor": 2
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}
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}
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}
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}
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}
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}
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----
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// AUTOSENSE
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<1> The function score query retrieves the script with filename `my_script.py`.
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