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PowerShell Requires Chilkat v11.7.0+

Box: Resolve a File Version by Name and Verify the Download

See more Box Examples

Run the reusable setup once per HttpCurl object, then select names and execute the operation. The setup is repeated here only to make this published example independently runnable. One target request requires file_id and file_version_id. The engine uses AddOutput2 for name lookups and AddOutput for version/SHA-1 metadata, then downloads that version to local_path and verifies its digest.

See the Box API guide for setup and the complete workflow.

Chilkat PowerShell Downloads

PowerShell
Add-Type -Path "C:\chilkat\ChilkatDotNet47-x64\ChilkatDotNet47.dll"

$success = $false

#  Requires Chilkat 11.7.0 or later and a previously unlocked Chilkat bundle.
#  See Global Unlock Sample.
#  Guide: Box API Guide.

$success = $false

#  BEGIN ONE-TIME SETUP
#  This block is repeated so each published example can run on its own.
#  In an application, run the setup example once and pass the SAME curl object
#  to operation code below. Do not recreate it for every operation.
#  See Reusable Box HttpCurl Setup.
$curl = New-Object Chilkat.HttpCurl
$curl.SetVar("access_token","BOX_ACCESS_TOKEN")
$curl.SetVar("parent_name","/")
#  Box's fixed root ID is an implementation detail; callers supply names.
$curl.SetVar("parent_id","0")
$setupCommand = New-Object Chilkat.StringBuilder

#  Register findParent; registration sends no request.
$setupCommand.SetString("curl -X GET `"https://api.box.com/2.0/folders/0/items?limit=1000&fields=id,type,name`" -H `"Authorization: Bearer ACCESS_TOKEN`"")
$setupReplacements = $setupCommand.Replace("ACCESS_TOKEN",$curl.GetVar("access_token"))
$success = $curl.AddFunction("findParent",$setupCommand.GetAsString())
if ($success -ne $true) {
    $($curl.LastErrorText)
    exit
}

#  Register findFolder; registration sends no request.
$setupCommand.SetString("curl -X GET `"https://api.box.com/2.0/folders/{{parent_id}}/items?limit=1000&fields=id,type,name`" -H `"Authorization: Bearer ACCESS_TOKEN`"")
$setupReplacements = $setupCommand.Replace("ACCESS_TOKEN",$curl.GetVar("access_token"))
$success = $curl.AddFunction("findFolder",$setupCommand.GetAsString())
if ($success -ne $true) {
    $($curl.LastErrorText)
    exit
}

#  Register findFile; registration sends no request.
$setupCommand.SetString("curl -X GET `"https://api.box.com/2.0/folders/{{folder_id}}/items?limit=1000&fields=id,type,name`" -H `"Authorization: Bearer ACCESS_TOKEN`"")
$setupReplacements = $setupCommand.Replace("ACCESS_TOKEN",$curl.GetVar("access_token"))
$success = $curl.AddFunction("findFile",$setupCommand.GetAsString())
if ($success -ne $true) {
    $($curl.LastErrorText)
    exit
}

#  Register findDestination; registration sends no request.
$setupCommand.SetString("curl -X GET `"https://api.box.com/2.0/folders/0/items?limit=1000&fields=id,type,name`" -H `"Authorization: Bearer ACCESS_TOKEN`"")
$setupReplacements = $setupCommand.Replace("ACCESS_TOKEN",$curl.GetVar("access_token"))
$success = $curl.AddFunction("findDestination",$setupCommand.GetAsString())
if ($success -ne $true) {
    $($curl.LastErrorText)
    exit
}

#  Register getFileDetails; registration sends no request.
$setupCommand.SetString("curl -X GET `"https://api.box.com/2.0/files/{{file_id}}?fields=id,sha1,file_version`" -H `"Authorization: Bearer ACCESS_TOKEN`"")
$setupReplacements = $setupCommand.Replace("ACCESS_TOKEN",$curl.GetVar("access_token"))
$success = $curl.AddFunction("getFileDetails",$setupCommand.GetAsString())
if ($success -ne $true) {
    $($curl.LastErrorText)
    exit
}

#  Register getEnterprise; registration sends no request.
$setupCommand.SetString("curl -X GET `"https://api.box.com/2.0/users/me?fields=enterprise`" -H `"Authorization: Bearer ACCESS_TOKEN`"")
$setupReplacements = $setupCommand.Replace("ACCESS_TOKEN",$curl.GetVar("access_token"))
$success = $curl.AddFunction("getEnterprise",$setupCommand.GetAsString())
if ($success -ne $true) {
    $($curl.LastErrorText)
    exit
}

#  Register output rules once. Chilkat 11.7.0 evaluates {{name}} variables
#  when extracting each output, using the current value at that time.
$success = $curl.AddOutput2("findParent","entries","name","{{parent_name}}",$true,"id","parent_id")
if ($success -ne $true) {
    $($curl.LastErrorText)
    exit
}

$success = $curl.AddOutput2("findFolder","entries","name","{{folder_name}}",$true,"id","folder_id")
if ($success -ne $true) {
    $($curl.LastErrorText)
    exit
}

$success = $curl.AddOutput2("findFile","entries","name","{{file_name}}",$true,"id","file_id")
if ($success -ne $true) {
    $($curl.LastErrorText)
    exit
}

$success = $curl.AddOutput2("findDestination","entries","name","{{destination_name}}",$true,"id","destination_id")
if ($success -ne $true) {
    $($curl.LastErrorText)
    exit
}

$success = $curl.AddOutput("getFileDetails","file_version.id","file_version_id")
if ($success -ne $true) {
    $($curl.LastErrorText)
    exit
}

$success = $curl.AddOutput("getFileDetails","sha1","file_sha1")
if ($success -ne $true) {
    $($curl.LastErrorText)
    exit
}

$success = $curl.AddOutput("getEnterprise","enterprise.id","enterprise_id")
if ($success -ne $true) {
    $($curl.LastErrorText)
    exit
}

#  END ONE-TIME SETUP
#  The name lookups below assume each listing fits in one page (1000 items).
#  Parent and destination names select root children; folder_name selects a child
#  of parent_name. "/" selects the root parent. These are not arbitrary paths.

#  BEGIN OPERATION -- keep the configured object when reusing it.
#  Inputs are names. Retain cached IDs when the selected names have not changed.
$parentName = "/"
$folderName = "images"
$fileName = "penguins.jpg"
if (($curl.GetVar("parent_name") -ne $parentName) -or (($parentName -eq "/") -and ($curl.VarDefined("parent_id") -eq $false))) {
    $curl.SetVar("parent_name",$parentName)
    $curl.ClearVar("parent_id")
    $curl.ClearVar("folder_id")
    $curl.ClearVar("file_id")
    $curl.ClearVar("file_version_id")
    $curl.ClearVar("file_sha1")
    if ($parentName -eq "/") {
        $curl.SetVar("parent_id","0")
    }

}

if ($curl.GetVar("folder_name") -ne $folderName) {
    $curl.SetVar("folder_name",$folderName)
    $curl.ClearVar("folder_id")
    $curl.ClearVar("file_id")
    $curl.ClearVar("file_version_id")
    $curl.ClearVar("file_sha1")
}

if ($curl.GetVar("file_name") -ne $fileName) {
    $curl.SetVar("file_name",$fileName)
    $curl.ClearVar("file_id")
    $curl.ClearVar("file_version_id")
    $curl.ClearVar("file_sha1")
}

$curl.SetVar("local_path","qa_output/penguins-verified.jpg")
#  file_version_id is also unknown, so getFileDetails becomes a prerequisite.
#  Its AddOutput mappings cache both the selected version and its SHA-1.
$curl.ClearTargetOutput("*")
$authorizedCommand1 = New-Object Chilkat.StringBuilder
$authorizedCommand1.SetString("curl -X GET `"https://api.box.com/2.0/files/{{file_id}}/content?version={{file_version_id}}`" -H `"Authorization: Bearer {{access_token}}`" -L -o `"{{local_path}}`"")
$headerReplacement1 = $authorizedCommand1.Replace("{{access_token}}",$curl.GetVar("access_token"))
$success = $curl.DoYourThing($authorizedCommand1.GetAsString())
if (($success -ne $true) -or ($curl.StatusCode -ne 200)) {
    $("Box request failed. HTTP status: " + $curl.StatusCode)
    $("Failure reason: " + $curl.FailReason)
    $($curl.ResponseBodyStr)
    exit
}

$digest = New-Object Chilkat.Crypt2
$digest.HashAlgorithm = "sha1"
$digest.EncodingMode = "hex_lower"
$actualSha1 = $digest.HashFileENC($curl.GetVar("local_path"))
if ($digest.LastMethodSuccess -ne $true) {
    $($digest.LastErrorText)
    exit
}

if ($actualSha1 -ne $curl.GetVar("file_sha1")) {
    $("Downloaded content did not match the selected version's SHA-1.")
    exit
}

$("Version-specific download verified.")