Auto-generated bicep file to read all config files in a directory

README.md

Bicep doesn't support loading all config files in a directory even if all filenames are hardcoded in a constant array.

• Azure/bicep#3607 - for each file in a directory
• Azure/bicep#3816 - loadTextContent() - support variable or parameter as input

A workaround for this is would be to generate a .bicep file that calls loadTextContent multiple times instead of in a loop. This can be done using T4 Text Templates

T4.Build nuget package contains MSBuild logic to generate the .bicep file and can be referenced in a .csproj that compiles the bicep files.

		<PackageReference Include="T4.Build" Version="0.2.4" PrivateAssets="All" />

Note: this works on Windows only

Alerts.tt

<#@ template debug="false" hostspecific="true" language="C#" #>
<#@ assembly name="System.Core" #>
<#@ import namespace="System.IO" #>
<#@ import namespace="System.Collections.Generic" #>
<#@ import namespace="System.Linq" #>
<#@ import namespace="Microsoft.VisualStudio.TextTemplating" #>
<#@ output extension=".bicep" #>
///
/// DO NOT EDIT Alerts.bicep
/// Autogenerated from Alerts.tt during the build
///

param location string
param appInsightsId string

<#
    var alertDefs = Directory.EnumerateFiles(this.Host.ResolvePath("."), "*.json")
                             .Select(f => Path.GetFileNameWithoutExtension(f));
#>
// Load all alerts defined in ./alerts folder
var alertDefinitions = [
<# foreach (var name in alertDefs) { #>
  {
    definition: loadTextContent('./alerts/<#= name #>.json')
  }
<# } #>
]

module monitorAlerts './modules/CreateAlert.bicep' = [for alert in alertDefinitions: {
  name: 'alert-${alert.definition.name}'
  params: {
    location: location
    appInsightsId: appInsightsId
    alertDefinition: alert.definition
    }
}]

sample.json

{
  "name": "sample",
  "severity": 3,
  "enabled": true,
  "evaluationFrequency": "PT10M",
  "windowSize": "PT30M",
  "criteria": {
    "timeAggregation": "Count",
    "dimensions": [],
    "operator": "GreaterThan",
    "threshold": 10,
    "failingPeriods": {
      "numberOfEvaluationPeriods": 1,
      "minFailingPeriodsToAlert": 1
    }
  },
  "autoMitigate": true,
}