Easy way to reference JSON arrays [duplicate] - json

I want to get a JSON representation of a Hashtable such as this:
#{Path="C:\temp"; Filter="*.js"}
ConvertTo-Json results in:
{
"Path": "C:\\temp",
"Filter": "*.js"
}
However, if you convert that JSON string back with ConvertFrom-Json you don't get a HashTable but a PSCustomObject.
So how can one reliably serialize the above Hashmap?

$json = #{Path="C:\temp"; Filter="*.js"} | ConvertTo-Json
$hashtable = #{}
(ConvertFrom-Json $json).psobject.properties | Foreach { $hashtable[$_.Name] = $_.Value }
Adapted from PSCustomObject to Hashtable

A little late to the discussion here, but in PowerShell 6 (Core) there is a -AsHashtable parameter in ConvertFrom-Json.

JavaScriptSerializer is available since .NET3.5 (may be installed on XP, included in Win7 and newer), it's several times faster than Convert-FromJSON and it properly parses nested objects, arrays etc.
function Parse-JsonFile([string]$file) {
$text = [IO.File]::ReadAllText($file)
$parser = New-Object Web.Script.Serialization.JavaScriptSerializer
$parser.MaxJsonLength = $text.length
Write-Output -NoEnumerate $parser.DeserializeObject($text)
}

The answer for this post is a great start, but is a bit naive when you start getting more complex json representations.
The code below will parse nested json arrays and json objects.
[CmdletBinding]
function Get-FromJson
{
param(
[Parameter(Mandatory=$true, Position=1)]
[string]$Path
)
function Get-Value {
param( $value )
$result = $null
if ( $value -is [System.Management.Automation.PSCustomObject] )
{
Write-Verbose "Get-Value: value is PSCustomObject"
$result = #{}
$value.psobject.properties | ForEach-Object {
$result[$_.Name] = Get-Value -value $_.Value
}
}
elseif ($value -is [System.Object[]])
{
$list = New-Object System.Collections.ArrayList
Write-Verbose "Get-Value: value is Array"
$value | ForEach-Object {
$list.Add((Get-Value -value $_)) | Out-Null
}
$result = $list
}
else
{
Write-Verbose "Get-Value: value is type: $($value.GetType())"
$result = $value
}
return $result
}
if (Test-Path $Path)
{
$json = Get-Content $Path -Raw
}
else
{
$json = '{}'
}
$hashtable = Get-Value -value (ConvertFrom-Json $json)
return $hashtable
}

I believe the solution presented in Converting JSON to a hashtable is closer to the PowerShell 6.0 implementation of ConvertFrom-Json
I tried with several JSON sources and I always got the right hashtable.
$mappings = #{
Letters = (
"A",
"B")
Numbers = (
"1",
"2",
"3")
Yes = 1
False = "0"
}
# TO JSON
$jsonMappings = $mappings | ConvertTo-JSON
$jsonMappings
# Back to hashtable
# In PowerShell 6.0 would be:
# | ConvertFrom-Json -AsHashtable
$jsonMappings | ConvertFrom-Json -As hashtable

you can write a function convert psobject to hashtable.
I wrote a answer here:enter link description here

Related

Powershell Parse Swagger Json

The following works to parse a Swagger json into resource, method, httptype but probably... the $path.Definition part is weirdly, how can i get $path.Definition to be an array not a string that i need to parse for the array symbol.
$json = Get-Content -Path "$PSScriptRoot/Test/example_swagger.json" | ConvertFrom-Json
$paths = Get-Member -InputObject $json.paths -MemberType NoteProperty
$result = ""
foreach($path in $paths) {
$elements = $path.Name.Substring(5).split("/") -join ","
$httpmethods = $path.Definition.Substring($path.Definition.IndexOf("#{"))
if ($httpmethods.Contains("get")) {
$result += $elements + ", GET" + "`n"
}
if ($httpmethods.Contains("post")) {
$result += $elements + ", POST" + "`n" #same methodnames different http methods
}
}
$result
As detailed in my answer to Iterating through a JSON file PowerShell, the output of ConvertFrom-Json is hard to iterate over. This makes "for each key in object" and "keys of object not known ahead of time" kinds of situations more difficult to handle, but not impossible.
You need a helper function:
# helper to turn PSCustomObject into a list of key/value pairs
function Get-ObjectMember {
[CmdletBinding()]
Param(
[Parameter(Mandatory=$True, ValueFromPipeline=$True)]
[PSCustomObject]$obj
)
$obj | Get-Member -MemberType NoteProperty | ForEach-Object {
$key = $_.Name
[PSCustomObject]#{Key = $key; Value = $obj."$key"}
}
}
with this, the approach gets a whole lot simpler:
$swagger = Get-Content -Path "example_swagger.json" -Encoding UTF8 -Raw | ConvertFrom-Json
$swagger.paths | Get-ObjectMember | ForEach-Object {
[pscustomobject]#{
path = $_.Key
methods = $_.Value | Get-ObjectMember | ForEach-Object Key
}
}
Applied to the default Swagger file from https://editor.swagger.io/ as a sample, this is printed
path methods
---- -------
/pet {post, put}
/pet/findByStatus get
/pet/findByTags get
/pet/{petId} {delete, get, post}
/pet/{petId}/uploadImage post
/store/inventory get
/store/order post
/store/order/{orderId} {delete, get}
/user post
/user/createWithArray post
/user/createWithList post
/user/login get
/user/logout get
/user/{username} {delete, get, put}

Find and Replace Nested JSON Values with Powershell

I have an appsettings.json file that I would like to transform with a PowerShell script in a VSTS release pipeline PowerShell task. (BTW I'm deploying a netstandard 2 Api to IIS). The JSON is structured like the following:
{
"Foo": {
"BaseUrl": "http://foo.url.com",
"UrlKey": "12345"
},
"Bar": {
"BaseUrl": "http://bar.url.com"
},
"Blee": {
"BaseUrl": "http://blee.url.com"
}
}
I want to replace BaseUrl and, if it exists, the UrlKey values in each section which are Foo, Bar and Blee. (Foo:BaseUrl, Foo:UrlKey, Bar:BaseUrl, etc.)
I'm using the following JSON structure to hold the new values:
{
"##{FooUrl}":"$(FooUrl)",
"##{FooUrlKey}":"$(FooUrlKey)",
"##{BarUrl}":"$(BarUrl)",
"##{BleeUrl}":"$(BleeUrl)"
}
So far I have the following script:
# Get file path
$filePath = "C:\mywebsite\appsettings.json"
# Parse JSON object from string
$jsonString = "$(MyReplacementVariablesJson)"
$jsonObject = ConvertFrom-Json $jsonString
# Convert JSON replacement variables object to HashTable
$hashTable = #{}
foreach ($property in $jsonObject.PSObject.Properties) {
$hashTable[$property.Name] = $property.Value
}
# Here's where I need some help
# Perform variable replacements
foreach ($key in $hashTable.Keys) {
$sourceFile = Get-Content $filePath
$sourceFile -replace $key, $hashTable[$key] | Set-Content $filePath
Write-Host 'Replaced key' $key 'with value' $hashTable[$key] 'in' $filePath
}
Why are you defining your replacement values as a JSON string? That's just going to make your life more miserable. If you're defining the values in your script anyway just define them as hashtables right away:
$newUrls = #{
'Foo' = 'http://newfoo.example.com'
'Bar' = 'http://newbaz.example.com'
'Blee' = 'http://newblee.example.com'
}
$newKeys = #{
'Foo' = '67890'
}
Even if you wanted to read them from a file you could make that file a PowerShell script containing those hashtables and dot-source it. Or at least define the values as lists of key=value lines in text files, which can easily be turned into hashtables:
$newUrls = Get-Content 'new_urls.txt' | Out-String | ConvertFrom-StringData
$newKeys = Get-Content 'new_keys.txt' | Out-String | ConvertFrom-StringData
Then iterate over the top-level properties of your input JSON data and replace the nested properties with the new values:
$json = Get-Content $filePath | Out-String | ConvertFrom-Json
foreach ($name in $json.PSObject.Properties) {
$json.$name.BaseUrl = $newUrls[$name]
if ($newKeys.ContainsKey($name)) {
$json.$name.UrlKey = $newKeys[$name]
}
}
$json | ConvertTo-Json | Set-Content $filePath
Note that if your actual JSON data has more than 2 levels of hierarchy you'll need to tell ConvertTo-Json via the parameter -Depth how many levels it's supposed to convert.
Side note: piping the Get-Content output through Out-String is required because ConvertFrom-Json expects JSON input as a single string, and using Out-String makes the code work with all PowerShell versions. If you have PowerShell v3 or newer you can simplify the code a little by replacing Get-Content | Out-String with Get-Content -Raw.
Thank you, Ansgar for your detailed answer, which helped me a great deal. Ultimately, after having no luck iterating over the top-level properties of my input JSON data, I settled on the following code:
$json = (Get-Content -Path $filePath) | ConvertFrom-Json
$json.Foo.BaseUrl = $newUrls["Foo"]
$json.Bar.BaseUrl = $newUrls["Bar"]
$json.Blee.BaseUrl = $newUrls["Blee"]
$json.Foo.Key = $newKeys["Foo"]
$json | ConvertTo-Json | Set-Content $filePath
I hope this can help someone else.
To update values of keys at varying depth in the json/config file, you can pass in the key name using "." between the levels, e.g. AppSettings.Setting.Third to represent:
{
AppSettings = {
Setting = {
Third = "value I want to update"
}
}
}
To set the value for multiple settings, you can do something like this:
$file = "c:\temp\appSettings.json"
# define keys and values in hash table
$settings = #{
"AppSettings.SettingOne" = "1st value"
"AppSettings.SettingTwo" = "2nd value"
"AppSettings.SettingThree" = "3rd value"
"AppSettings.SettingThree.A" = "A under 3rd"
"AppSettings.SettingThree.B" = "B under 3rd"
"AppSettings.SettingThree.B.X" = "Z under B under 3rd"
"AppSettings.SettingThree.B.Y" = "Y under B under 3rd"
}
# read config file
$data = Get-Content $file -Raw | ConvertFrom-Json
# loop through settings
$settings.GetEnumerator() | ForEach-Object {
$key = $_.Key
$value = $_.Value
$command = "`$data.$key = $value"
Write-Verbose $command
# update value of object property
Invoke-Expression -Command $command
}
$data | ConvertTo-Json -Depth 10 | Out-File $file -Encoding "UTF8"

PowerShell JSON adding value format

I am adding data to a json file. I do this by
$blockcvalue =#"
{
"connectionString":"server=(localdb)\\mssqllocaldb; Integrated Security=true;Database=$database;"
}
"#
$ConfigJson = Get-Content C:\Users\user\Desktop\myJsonFile.json -raw | ConvertFrom-Json
$ConfigJson.data | add-member -Name "database" -value (Convertfrom-Json $blockcvalue) -MemberType NoteProperty
$ConfigJson | ConvertTo-Json| Set-Content C:\Users\user\Desktop\myJsonFile.json
But the format comes out like this:
{
"data": {
"database": {
"connectionString": "server=(localdb)\\mssqllocaldb; Integrated Security=true;Database=mydatabase;"
}
}
}
but I need it like this:
{
"data": {
"database":"server=(localdb)\\mssqllocaldb; Integrated Security=true;Database=mydatabase;"
}
}
}
Can someone help please?
Here's my function to prettify JSON output:
function Format-Json {
<#
.SYNOPSIS
Prettifies JSON output.
.DESCRIPTION
Reformats a JSON string so the output looks better than what ConvertTo-Json outputs.
.PARAMETER Json
Required: [string] The JSON text to prettify.
.PARAMETER Indentation
Optional: The number of spaces to use for indentation. Defaults to 2.
.PARAMETER AsArray
Optional: If set, the output will be in the form of a string array, otherwise a single string is output.
.EXAMPLE
$json | ConvertTo-Json | Format-Json -Indentation 4
#>
[CmdletBinding()]
Param(
[Parameter(Mandatory = $true, Position = 0, ValueFromPipeline = $true)]
[string]$Json,
[int]$Indentation = 2,
[switch]$AsArray
)
# If the input JSON text has been created with ConvertTo-Json -Compress
# then we first need to reconvert it without compression
if ($Json -notmatch '\r?\n') {
$Json = ($Json | ConvertFrom-Json) | ConvertTo-Json -Depth 100
}
$indent = 0
$Indentation = [Math]::Abs($Indentation)
$regexUnlessQuoted = '(?=([^"]*"[^"]*")*[^"]*$)'
$result = $Json -split '\r?\n' |
ForEach-Object {
# If the line contains a ] or } character,
# we need to decrement the indentation level unless it is inside quotes.
if ($_ -match "[}\]]$regexUnlessQuoted") {
$indent = [Math]::Max($indent - $Indentation, 0)
}
# Replace all colon-space combinations by ": " unless it is inside quotes.
$line = (' ' * $indent) + ($_.TrimStart() -replace ":\s+$regexUnlessQuoted", ': ')
# If the line contains a [ or { character,
# we need to increment the indentation level unless it is inside quotes.
if ($_ -match "[\{\[]$regexUnlessQuoted") {
$indent += $Indentation
}
$line
}
if ($AsArray) { return $result }
return $result -Join [Environment]::NewLine
}
Use it like so:
$ConfigJson | ConvertTo-Json | Format-Json | Set-Content C:\Users\user\Desktop\myJsonFile.json
Replace
(Convertfrom-Json $blockcvalue)
with
(Convertfrom-Json $blockcvalue).connectionString
Then your output object's data.database property will directly contain the "server=(localdb)\\..." value, as desired, not via a nested object that has a connectionString property.
There is one simple Newtonsoft.Json Parser which makes it rly simple to get required format:
Import-Module Newtonsoft.Json
$path = "C:\..."
$json = Get-Content -Path $path -Raw
$parsedJson = [Newtonsoft.Json.Linq.JToken]::Parse($json);
Set-Content $path $parsedJson.ToString();
Enjoy ;)

Create Hashtable from JSON

I want to get a JSON representation of a Hashtable such as this:
#{Path="C:\temp"; Filter="*.js"}
ConvertTo-Json results in:
{
"Path": "C:\\temp",
"Filter": "*.js"
}
However, if you convert that JSON string back with ConvertFrom-Json you don't get a HashTable but a PSCustomObject.
So how can one reliably serialize the above Hashmap?
$json = #{Path="C:\temp"; Filter="*.js"} | ConvertTo-Json
$hashtable = #{}
(ConvertFrom-Json $json).psobject.properties | Foreach { $hashtable[$_.Name] = $_.Value }
Adapted from PSCustomObject to Hashtable
A little late to the discussion here, but in PowerShell 6 (Core) there is a -AsHashtable parameter in ConvertFrom-Json.
JavaScriptSerializer is available since .NET3.5 (may be installed on XP, included in Win7 and newer), it's several times faster than Convert-FromJSON and it properly parses nested objects, arrays etc.
function Parse-JsonFile([string]$file) {
$text = [IO.File]::ReadAllText($file)
$parser = New-Object Web.Script.Serialization.JavaScriptSerializer
$parser.MaxJsonLength = $text.length
Write-Output -NoEnumerate $parser.DeserializeObject($text)
}
The answer for this post is a great start, but is a bit naive when you start getting more complex json representations.
The code below will parse nested json arrays and json objects.
[CmdletBinding]
function Get-FromJson
{
param(
[Parameter(Mandatory=$true, Position=1)]
[string]$Path
)
function Get-Value {
param( $value )
$result = $null
if ( $value -is [System.Management.Automation.PSCustomObject] )
{
Write-Verbose "Get-Value: value is PSCustomObject"
$result = #{}
$value.psobject.properties | ForEach-Object {
$result[$_.Name] = Get-Value -value $_.Value
}
}
elseif ($value -is [System.Object[]])
{
$list = New-Object System.Collections.ArrayList
Write-Verbose "Get-Value: value is Array"
$value | ForEach-Object {
$list.Add((Get-Value -value $_)) | Out-Null
}
$result = $list
}
else
{
Write-Verbose "Get-Value: value is type: $($value.GetType())"
$result = $value
}
return $result
}
if (Test-Path $Path)
{
$json = Get-Content $Path -Raw
}
else
{
$json = '{}'
}
$hashtable = Get-Value -value (ConvertFrom-Json $json)
return $hashtable
}
I believe the solution presented in Converting JSON to a hashtable is closer to the PowerShell 6.0 implementation of ConvertFrom-Json
I tried with several JSON sources and I always got the right hashtable.
$mappings = #{
Letters = (
"A",
"B")
Numbers = (
"1",
"2",
"3")
Yes = 1
False = "0"
}
# TO JSON
$jsonMappings = $mappings | ConvertTo-JSON
$jsonMappings
# Back to hashtable
# In PowerShell 6.0 would be:
# | ConvertFrom-Json -AsHashtable
$jsonMappings | ConvertFrom-Json -As hashtable
you can write a function convert psobject to hashtable.
I wrote a answer here:enter link description here

ConvertFrom-Json in Powershell v2

Code
I have the following script, largely based off information on this site:
cls
if ($PSVersionTable.PSVersion.Major -lt 3) {
function ConvertTo-Json([psobject] $item){
[System.Reflection.Assembly]::LoadWithPartialName("System.Web.Extensions") | out-null
$ser = New-Object System.Web.Script.Serialization.JavaScriptSerializer
$hashed = #{}
$item.psobject.properties | %{ $hashed.($_.Name) = $_.Value }
write-output $ser.Serialize($hashed)
}
function ConvertFrom-Json([string] $json){
[System.Reflection.Assembly]::LoadWithPartialName("System.Web.Extensions") | out-null
$ser = New-Object System.Web.Script.Serialization.JavaScriptSerializer
write-output (new-object -type PSObject -property $ser.DeserializeObject($json))
}
}
$jsonObj = (new-object -type psobject -property #{
MyDummyData = #{
Version = '1.0.4'
CreationDate = ("{0:yyyy-MM-ddTHH:mm:ss.fffZ}" -f ((Get-Date).ToUniversalTime()))
Demo = 'hello'
Recurse = #{
Hello = "hi"
Greetings = #{
what = "now"
}
}
}
})
"`n`nobj"
$jsonObj
"`n`nobj to json"
$jsonx = ConvertTo-Json($jsonObj)
$jsonx
"`n`njson to obj"
$x = ConvertFrom-Json($jsonx)
$x
"Compare"
$x -eq $jsonObj
Output
obj
MyDummyData
-----------
{Version, Demo, CreationDate, Recurse}
obj to json
{"MyDummyData":{"Version":"1.0.4","Demo":"hello","CreationDate":"2015-07-23T18:
59:04.265Z","Recurse":{"Greetings":{"what":"now"},"Hello":"hi"}}}
json to obj
{[Version, 1.0.4], [Demo, hello], [CreationDate, 2015-07-23T18:59:04.265Z], ...
Compare
False
Problem
When I test it ConvertTo-Json works perfectly.
However ConvertFrom-Json doesn't resolve to the object I started with, but rather gives me an object containing a number of name-value pairs.
Question
Can anyone spot what I've missed; or are the methods proposed on here only suitable in certain scenarios?
Related
Example of existing answer: PowerShell 2.0 ConvertFrom-Json and ConvertTo-Json implementation