Overview of the Historian REST APIs

Introduction

The REST APIs are used to fetch data from the Historian database. You can fetch data such as the latest data point of a tag or data points for a duration. Using these APIs, you can also work on aggregation techniques like average, minimum, and maximum values.

Modify REST API User on Azure

To modify the REST API on Azure, follow these steps:

  1. Login to Azure portal.
  2. Go to the resource group in which CloudHistorian is deployed.
  3. Go to <cluster-name> Kubernetes service -> Configuration.
  4. Under the Config maps section, filter by default namespace.
  5. Select rest-api-cm and then click on YAML and scroll down to the data section.

  6. Modify user name under HISTORIAN_USERNAME field and password under HISTORIAN_PASSWORD field.

  7. Click Review and Save.

  8. Go to <cluster-name> Kubernetes service -> Workloads -> Filter by default namespace.

  9. Select rest-api-deployment under deployment section.

  10. Under Pods section select rest-api-deployment-xxxxxx.

  11. Click Delete.

    This will restart rest API pod with new changes.

Change Debug mode of Data Archiver

To change the debug mode for the Data Archiver, follow these steps:

  1. Login to Azure portal.
  2. Go to the resource group in which CloudHistorian is deployed.
  3. Go to <cluster-name> Kubernetes service -> Configuration.
  4. Under the Config maps section, filter by default namespace.
  5. Select hist-config, and then click on YAML and scroll down to the data section.
  6. Modify debug field to on / off .
  7. Click Review and Save.

  8. Go to <cluster-name> Kubernetes service.
  9. Select Workloads and choose the Filter default namespace.
  10. Under the Stateful sets section, select historian-archiver-sts.

  11. Under Pods section select historian-archiver-sts-0.

  12. Click Delete.

    This action will restart Data Archiver pod with new changes.