Tableau Web Data Connector for Elasticsearch
This is an instance of a Tableau Web Data Connector for Elasticsearch. This will extract a set of data from Elasticsearch based on the cluster URL, index name, type and optional custom query and create a Tableau extract of the data. The connector will query the specified type's mapping in Elasticsearch to report the fields and data types that Tableau can expect to see.
This connector should be periodically refreshed, as the extract only includes data from the point in time that it was executed.
The connector works by retrieving 'pages' of data from Elasticsearch up to either the limit specified, or up to the total number of hits. The user can override the batch size to retrieve more records per page if desired.
- Fields with
arrayorobjectthey will be ignored
- You must enable CORS support in your Elasticsearch server. Set the following setting in
elasticsearch.yml:
http.cors.enabled: trueAdditionally, in current versions of Elasticsearch (2.3+), it is required to define which origins
are allowed to send CORS requests (this is defined by the origin HTTP request header). The following configuration in elasticsearch.yml will allow ALL origins but is
considered insecure:
http.cors.allow-origin: "*"If you use some other front end HTTP proxy in front of your Elasticsearch cluster, you will need to make sure that CORS requests are allowed, including authorization headers.
For more detailed information on Elasticsearch configuration options refer to: Elasticsearch Configuration Reference
Install grunt:
npm install -g grunt
Install bower:
npm install -g bower
Run the following from the command line:
npm install
bower install
From the command line execute:
grunt build:dist
This will package the connector files in the dist folder, combining javascript and CSS into single files.
You can build, watch sources for changes, and run the application at the command line with grunt with:
grunt
This will watch all sub-directories for changes and reload the application if anything changes. Running this app will simply host all the connector resources but when requested stand alone will not do anything useful. You should either use the connector within the Web Data Connector SDK test harness, or use the connector from Tableau Desktop or Server.
Note that internally there are tasks that run the
build:devtarget, to perform HTML templating, and copy all source files to thepublic/source folder where the NodeJS server will serve static resources from
Make note of the URL that the connector app is running on, e.g.:
Elasticsearch Tableau Web Data connector server listening at http://0.0.0.0:3000
Simply choose the 'Web Data Connector' as your data source from within Tableau Desktop, or use the Web Connector SDK and enter the URL..
A Dockerfile is supplied in docker/Dockerfile that will build an image that creates a development build of the
latest source from Github, and runs the node server.
You can build an image from the root of the project:
docker build docker -t <name of tag>
and can then start a container, which will map the server to the host's port 3000 from this image with:
docker run <name of tag> -p 3000:3000
For convenience, the connector comes with winser to install the connector web server as a Windows service.
To install as a Windows service:
npm run-script install-service
This will install a service named elasticsearch-tableau-connector. Open the
Windows service manager (services.msc) to start the service.
To uninstall the service:
npm run-script uninstall-service
Execute the build for this project from the command line:
grunt build:dist
For each file in the dist/ folder, import into Tableau Server by:
- Ensure the Tableau command line tools are in your PATH
- From a command line (and your working director is the
dist/folder) execute the following:
tabadmin import_webdataconnector elasticsearch-connector.html
tabadmin import_webdataconnector elasticsearch-connector.min.css
tabadmin import_webdataconnector elasticsearch-connector.min.js
Get the URL of the elasticsearch-connector.html on the Tableau Server by executing:
tabadmin list_webdataconnectors --urls
And from Tableau go to 'Web Data Connector' and enter the URL of the connector:
http://<your tableau server>/webdataconnectors/elasticsearch-connector.html
If you are running this web app locally, and testing from the Tableau Web Data Connector SDK, simply enter:
http://localhost:3000/elasticsearch-connector.html
into the Web Connector URL input field in the SDK's form.
From there you should see this connector's UI:
The Elasticsearch connector UI includes the following fields:
| Field Name | Data Type | Description |
|---|---|---|
| Connection Name | String | Name of the data source connection displayed in the Tableau workbook |
| Elasticsearch URL | String | [Required] URL of the Elasticsearch cluster |
| Use HTTP Basic authentication | Boolean | [Required] Indicates if the Elasticsearch cluster requires HTTP Basic Auth |
| Username | String | If 'Use HTTP Basic Auth' is checked, this is the user name |
| Password | String | If 'Use HTTP Basic Auth' is checked, this is the password |
| Index name | String | [Required] Name of the index in the Elasticsearch cluster |
| Type | String | [Required] Name of the type in the Elasticsearch cluster to query |
| Use custom query? | Boolean | If true, indicates if the extract should use a custom query against Elasticsearch, if false extract will be a 'match all' |
| Query | String | If Use custom query? is true, this will be the JSON request payload sent to Elasticsearch. from, and size will be overwritten if supplied. Refer to Elasticsearch Query DSL for a reference on writing a query |
| Batch size of per request to Elasticsearch | Integer | Number of rows to retrieve at once, defaults to 10, should probably be 1000+ |
| Total limit on numnber of rows to sync | Integer | Limit of rows to include in extract, defaults to 100, but generally should be left blank to indicate that all matching rows should be included |
The 'Submit' button will execute the extract and report the total number of rows and the executing time when completed.
For geo_point fields in Elasticsearch, this connector will create two separate Tableau fields by parsing the lat, lon value:
- Latitude - field will be named
<field-name>_latitude- float type - Longitude - field will be named
<field-name>_longitude- float type