Public/Add-Relation.ps1
|
function Add-Relation { <# .SYNOPSIS Add a relation to a erDiagram. .DESCRIPTION Add a relation to a er diagram. Used entities do not to be defined before. .INPUTS Mermaid diagram definition object. .OUTPUTS None. .EXAMPLE PS C:\> $diagram = New-MermaidDiagram -Type erDiagram PS C:\> $diagram | Add-MermaidRelation Exactly-one Customer places Zero-or-more Order PS C:\> $diagram | Add-MermaidRelation Exactly-one Order contains One-or-more LineItem PS C:\> $diagram | Add-MermaidRelation One-or-more Customer uses One-or-more DeliveryAddress -NonIdentifying PS C:\> $diagram | ConvertTo-MermaidString erDiagram Customer ||--o{ Order : places Order ||--|{ LineItem : contains Customer }|..|{ DeliveryAddress : uses Create a erDiagram, add a few relations and convert it to a diagram string. .LINK https://mermaid-js.github.io/mermaid/#/entityRelationshipDiagram?id=entities-and-relationships #> [CmdletBinding()] param ( # The diagram, that the relation is added to. [Parameter(ValueFromPipeline)] $Diagram, # The first entity of the relation. [Parameter(Mandatory, ParameterSetName='Entity')] [ValidateNotNullOrEmpty()] [string] $Entity, # The first entity of the relation. [Parameter(Mandatory, Position = 1, ParameterSetName='Relation')] [ValidateNotNullOrEmpty()] [string] $FirstEntity, # How often the first entity exists in the relation. [Parameter(Mandatory, Position = 0, ParameterSetName='Relation')] [ValidateSet('Zero-or-one', 'Exactly-one', 'Zero-or-more', 'One-or-more')] [string] $FirstCardinality, # The second entity of the relation. [Parameter(Mandatory, Position = 4, ParameterSetName='Relation')] [ValidateNotNullOrEmpty()] [string] $SecondEntity, # How often the second entity exists in the relation. [Parameter(Mandatory, Position = 3, ParameterSetName='Relation')] [ValidateSet('Zero-or-one', 'Exactly-one', 'Zero-or-more', 'One-or-more')] [string] $SecondCardinality, # Describes the relationship. [Parameter(Mandatory, Position = 2, ParameterSetName='Relation')] [string] $Label, # Specifies if one of the entities may exist without the other. [Parameter(ParameterSetName='Relation')] [switch] $NonIdentifying ) switch ( $PSCmdlet.ParameterSetName ) { Relation { $Diagram.Relations += [PSCustomObject]@{ FirstEntity = $FirstEntity Relationship = [PSCustomObject]@{ FirstCardinality = $FirstCardinality SecondCardinality = $SecondCardinality Identifying = -Not $NonIdentifying.IsPresent } SecondEntity = $SecondEntity Label = $Label } } Entity { $Diagram.Relations += [PSCustomObject]@{ FirstEntity = $Entity } } } } |