Simple template variable usage

Prerequisites

Modules

• osp-web

• osp-variables

Checkout branches

git checkout origin/osp-web-configuration .
git checkout origin/osp-waveforms-configuration .

Example configuration

git checkout origin/example-variables-usage .

Description

In this tutorial, the usage of template variables is described. The focus is done to to understand the prevalence of usage and all the types of variables available.

Example

Steps

1. Create a waveform value constant

root/template/final/owner.waveforms

{
    "moduleId": "modules.waveforms.waveforms-1",
    "waveformConfigurationEntity" : {
        "value": 10,
        "type": "CONSTANT"
    },
    "samplePeriod": {
        "unit": "DAYS",
        "value": 1
    }
}

root/template/final/value.ospp

{
    "name" : "Final value",
    "description": "${description} - ${from-template-of-template}",
    "type": "INTEGER",
    "preTransform": "${pre-transform-var}",
    "templateId": "root.template",
    "templateVariables" : {
        "description" : "Description variable",
        "pre-transform-var" : {
            "transform": "add(value,1)"
        }
    }
}

• The pre-transform value come from the value.ospp file (to show the same file templateVariable definition).

• The description use two variables ${description} who is defined inside the same file

• The from-template-of-template variable who is undefined (will be done in next step)

• A reference is done to root.template via the templateId key

2. Create a first level of template

root/template/template/value.ospp.template

{
    "templateId" : "root.template-of-template",
    "templateVariables" : {
        "from-template-of-template": "This description is overriden"
    }
}

• This value describe a variable who is not used (description), because the variable is defined in the root.final/value.ospp

• A sub-template is defined by the templateVariables key

3. Create a second level of template

root/template/from-template-of-template/value.ospp.template

{
    "templateVariables" : {
        "description": "from-template of template value"
    }
}

• This file declare the variable from-template-of-template. Used by the root.final/value.ospp

4. Add dashboard to visualize the result

This files are used to visualize the example

{
    "configuration": [
      {
        "type": "ValueSubscription",
        "id": "xMkAMwzR",
        "title": "",
        "valueSubscriptions": {
          "values": [
            {
              "id": "root.final",
              "right": "READ_WRITE"
            }
          ]
        }
      }
    ],
    "layout": {
      "lg": [
        {
          "w": 12,
          "h": 5,
          "x": 0,
          "y": 0,
          "i": "xMkAMwzR"
        }
      ]
    },
    "breakpoints": {
      "lg": 1200,
      "md": 996,
      "sm": 768,
      "xs": 480,
      "xxs": 0
    },
    "cols": {
      "lg": 12,
      "md": 10,
      "sm": 6,
      "xs": 4,
      "xxs": 2
    },
    "rowHeight": 150
  }

{
    "moduleId": "modules.web.web-1",
    "title": "Home",
    "description": "OnSphere home",
    "tags": []
}

5. Check result

See the result on the dashbaord (hostname:5000), log with default user (user) and password (onsphere)

This schema show from where each value come from and the rules.

1. In red, we have a value declared inside a template, but override locally

2. In green, we have the value who override the red value

3. In purple, we have a variable declared in template of template

4. In Orange, we have a node insertion (locally defined)