Using Powershell, I'm trying to PUT data into an API, but I'm having trouble using a variable within the JSON:
This code below does not generate an error from the API, but it PUTS the singer as, literally, "$var_currentsinger" and doesn't use the intended variable
$currentsinger = "Michael Jackson"
$headers.Add("Content-Type", "application/json")
$response = Invoke-WebRequest -Uri https://stackoverflow.com -Method PUT -Headers $headers -Body '{
"album": {
"name": "Moonlight Sonata",
"custom_fields": [{
"singer": "$currentsinger",
"songwriter": "Etta James"
}]
}
}'
This version below does not work, I assume because there are no quotes around the singer name. The API returns a value that the data is invalid
$currentsinger = "Michael Jackson"
$headers.Add("Content-Type", "application/json")
$response = Invoke-WebRequest -Uri https://stackoverflow.com -Method PUT -Headers $headers -Body '{
"album": {
"name": "Moonlight Sonata",
"custom_fields": [{
"singer": $currentsinger,
"songwriter": "Etta James"
}]
}
}'
The only thing I have tried is double quotes and triple quotes around the variable, but I either get the $currentsinger variable within the JSON and have it submit the variable value and not the variable name.
JSON requires double-quotes, so one example way to handle is by escaping the quotes or with a double-quoted here-string:
# here-string
$json = #"
"singer": $currentsinger,
"songwriter": "Etta James"
"#
# escaped
$json = "
`"singer`": $currentsinger,
`"songwriter`": `"Etta James`"
"
Related
I have the following call to an API in a powershell script (Powershell 4.0):
$Json = Invoke-WebRequest -Uri $RequestURL -UseBasicParsing -Headers $headers -ContentType 'application/json; charset=utf-8' -Method POST -Body $postParams -TimeoutSec 40
...and the content of the response (which is a string in JSON format) is written to a file:
Set-Content $path -Value $Json.Content
An example of a typical response...
{
"MyArray": [{
"MyField": "A1",
"MyField2": "A2"
}, {
"MyField": "B1",
"MyField2": "B2"
}]
}
All well and good, but now I have a requirement to parse the returned content as JSON and query some properties from within this Powershell script.
I presume I need to convert my string to 'proper' JSON and then to a powershell object in order to access the properties...so I have tried combinations of ConvertTo-Json and ConvertFrom-Json but can't ever seem to access it in anything other than a string. For example...
$x = $Json.Content | ConvertTo-Json
Write-Host $x.MyArray[0].MyField
$y = $x | ConvertFrom-Json
Write-Host $y[0].MyArray[0].MyField
In both cases above I get an error "Cannot index into a null array" suggesting that MyArray is null.
How do I convert my $Json response object into an object I can drill down into?
See ConvertFrom-Json
Converts a JSON-formatted string to a custom object or a hash table.
The ConvertFrom-Json cmdlet converts a JavaScript Object Notation
(JSON) formatted string to a custom PSCustomObject object that has a
property for each field in the JSON string.
Once you get the response converted to custom object or a hash table, you can access the individual properties
The link includes coding examples
This seems to work...
[void][System.Reflection.Assembly]::LoadWithPartialName("System.Web.Extensions")
$x = (New-Object -TypeName System.Web.Script.Serialization.JavaScriptSerializer -Property #{MaxJsonLength=67108864}).DeserializeObject($Json.Content)
Write-Host $x.MyArray[0].MyField
...although not sure why yet.
I need to perform an Invoke-Webrequest with a specifically formatted body to add devices to a product. Here is what it looks like in json (example straight from the vendor's documentation):
$body_json = '{"datasource": [{
"parentId": "123456789000",
"name": "(name)",
"id": "(value)",
"typeId": 0,
"childEnabled": false,
"childCount": 0,
"childType": 0,
"ipAddress": "(ipAddress)",
"zoneId": 0,
"url": "(url)",
"enabled": false,
"idmId": 123456789000,
"parameters": [{
"key": "(key)",
"value": "(value)"
}]
}]}'
When I try to submit this in its json representation though, I get the following error:
Invoke-WebRequest : Can not deserialize instance of
com.vendor.etc.DataSourceDetail out of START_ARRAY token at [Source:
java.io.StringReader#22c614; line: 1, column: 1] At
C:\powershell_script_location\ps.ps1:114 char 9
+ $request = Invoke-WebRequest $url -Method Post -Headers $headers -Body $body_json - ...
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : InvalidOperation:
(System.Net.HttpWebRequest:HttpWebRequest) [Invoke-WebRequest],
WebException + FullyQualifiedErrorId :
WebCmdletWebResponseException,Microsoft.PowerShell.Commands.InvokeWebRequestCommand
The issue is with the format of the "parameters", parameter because the request submits fine when omitting the "parameters", but then the
devices that I'm adding are missing important parameter details.
Is there something wrong with Invoke-WebRequest, JavaScriptSerializer,
the vendor's code, or is this a user error? Let me know if any clarification is needed.
Unfortunately I don't know what a com.vendor.etc.DataSourceDetail instance looks like, as I am using an API and I don't have access to it directly.
Use Invoke-RestMethod instead of Invoke-WebRequest.
If you have the body as a string use:
Invoke-RestMethod -Uri http://your-url.com -Method POST -Body $body_json -ContentType "application/json"
If the body must be constructed from data/parameters, it might be easier to build a hashtable and convert it to json via ConvertTo-Json:
$body_json = #{
datasource = #(
#{
parentId = 123456789000
name = "name"
id = "value"
typeId = 0
childEnabled = $false
childCount = 0
childType = 0
ipAddress = "ipAddress"
zoneId = 0
url = "url"
enabled = $false
idmId = 123456789000
parameters = #( #{
key = "key"
value = "value"
})
})} | ConvertTo-Json -Depth 4
Invoke-RestMethod -Method 'Post' -Uri http://your-url.com -Body $body_json -ContentType "application/json"
Body Undefined
I couldn't understand why the req.body on the server was undefined (NodeJS Azure Function). It turns out I had a header that was an empty string.
It's not clear whether is was invoke-restmethod or azure-functions-core-tools that has a bug.
FWIW.
I'm trying to make a POST request to my server. Everything was fine until I decided to convert my object to JSON. Here's my code:
$postParams = #{
Login = "JonSnow66";
Password = "LetItSnow";
Email = "Jon.Snow#wall.com";
Name = "Jon Snow";
Desc = "I know nothing";
BirthDate = "1572 2 16";
Img = Get-Content -Path ./PH_img.txt | Out-String;
Type = "Admin";
}
Invoke-WebRequest -Uri http://localhost:3000/api/add/user -Method POST -Body (ConvertTo-Json $postParams -Compress)
Instead of returning regular JSON object like:
{
"Login": "JonSnow66"
...
}
It returns:
{{
"Login": "JonSnow66",
"BirthDate": "1572 2 16",
"Desc": "I know nothing",
"Name": "Jon Snow",
"Type": "Admin",
"Password": "LetItSnow",
"Img": "/9j/4<BASE64>/Z\r\n",
"Email": "Jon.Snow#wall.com"
}: ""}
I'm just a powershell beginner.
I think you need to specify ContentType on Invoke-WebRequest to be 'application/json'. If you don't specify a content type and are performing a Post then I think the cmdlet assumes you are submitting a form by default, and that might explain the extra { } characters you are seeing in the result.
Here's the modified code:
Invoke-WebRequest -Uri 'http://localhost:3000/api/add/user' -Method POST -ContentType 'application/json' -Body (ConvertTo-Json $postParams -Compress)
I am trying to add a parent link to a TFS work item using powershell and json. We have an internal TFS server (ie, not team services).
I get answers to my queries, so my connection to TFS is working, but when I try to update I get the following error:
"You must pass a valid patch document in the body of the request."
I am a json noob and got my json skeleton from this MSDN page
Here is my json:
[
{
"op": "add",
"path": "/relations/-",
"value":
{
"rel": "System.LinkTypes.Hierarchy-Reverse",
"url": "https://tfs.myCompany.org/tfs/DefaultCollection/_apis/wit/workitems/259355",
"attributes":
{
{ "isLocked": false }
}
}
}
]
I tested with square brackets in a few places based on some other json samples I found but they didn't help so I returned to the syntax from the MSDN page above.
And this is the powershell script I am using.
param(
[System.String]$TaskId=288346
)
$username = "myUserInfo"
$password = "myPassword"
$securePassword = $password | ConvertTo-SecureString -AsPlainText -Force
$credential = New-Object System.Management.Automation.PSCredential($username, $securePassword)
$taskItemURL ="https://tfs.myCompanynet.org/tfs/DefaultCollection/_apis/wit/workitems/$TaskId"
$taskItemRequest = $taskItemUrl+'?$expand=relations'
$taskItemJson = Invoke-RestMethod -uri "$taskItemRequest" -Method get -
Credential $credential
if($taskItemJson.relations)
{
write-host "relation exists: " $taskItemJson.relations[0].url
}
else
{
write-host "relation does not exist. Creating it."
$jsonTemplate = Get-Content E:\scripts\JsonTemplate.txt # | ConvertTo-Json
$result = Invoke-RestMethod -uri $taskItemURL"?api-version=1.0" -Method patch -UseDefaultCredentials -ContentType application/json-patch+json -body $jsonTemplate
}
As you can see I have commented out the convertTo-json because I was getting this error:
ConvertTo-Json : The converted JSON string is in bad format.
I wasn't sure if I was getting that error because it is already json.
I also tested skipping the get-content and using the -inFile parameter but it resulted in the same error above.
$result = Invoke-RestMethod -uri $taskItemURL"?api-version=1.0" -Method patch -Credential $credential -ContentType application/json-patch+json -InFile E:\scripts\JsonTemplate.txt
Any ideas on what is wrong with my json?
Thanks!
Aargh! I was so close. I chanced a guess that the double curly brackets under attribrutes were wrong even though the documentation looks like it should be so. When I removed those it worked beautifully.
Now my json looks like this:
[
{
"op": "add",
"path": "/relations/-",
"value":
{
"rel": "System.LinkTypes.Hierarchy-Reverse",
"url": "https://tfs.myCompany.org/tfs/DefaultCollection/_apis/wit/workitems/259355",
"attributes":
{
"isLocked": false
}
}
}
]
I was able to pass the dynamic json object if the object creation code is in single line.
Invoke-RestMethod -ContentType "application/json" -Method Post -Body '{ "name" : "azurefunctionapp2email", "appname": "Applicationnamehere", "requestedBy" : "requestedby", "reqdate" : "requestdate", "status" : "Successfully Deployed", "AppsCount" : "2" }' `
-Uri “https://implementurihere"
Since the dynamic JSON object in real world need be longer, I seperated created with new line and referenced in the above as below. But new line shift causes the json to break. I tried to pipe to ConvertTo-Json function and then found the output to hold '`\r\n' getting introduced:
$body = '{ "name" : "azurefunctionapp2email", `
"appname": "Applicationnamehere", `
"requestedBy" : "requestedby", `
"reqdate" : "requestdate",
"status" : "Successfully Deployed",
"AppsCount" : "2" }' `
Invoke-RestMethod -ContentType "application/json" -Method Post -Body $body `
-Uri “https://implementurihere"
Note: The above works if the $body is single line.
How to approach in such scenarios where we create a dynamic json , long file and feed?
Your example doesn't work because the last line containing a backtick which you have to omit.
You could use a here string to define your JSON so you don't need to seperate each line by a backtick:
$body =
#'
{ "name" : "azurefunctionapp2email",
"appname": "Applicationnamehere",
"requestedBy" : "requestedby",
"reqdate" : "requestdate",
"status" : "Successfully Deployed",
"AppsCount" : "2" }
'#
You could also consider to use a PowerShell hashtable to define your object which will allows you to use variables without the need of a format string:
$bodyObject = #{
name = 'azurefunctionapp2email'
appname = 'Applicationnamehere'
requestedBy = 'requestedby'
reqdate = 'requestdate'
status = 'Successfully Deployed'
AppsCount = '2'
}
$bodyObject | ConvertTo-Json