Classes/OpenAiChat.psm1
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using module "..\Private\OutHelper.psm1" using namespace System using namespace System.Text using namespace System.IO using namespace System.Net.Http using namespace System.Net.Http.Formatting using namespace System.Net.Http.Headers using namespace System.Web using namespace System.Web.Extensions class OpenAiChatFunctionCall { [string]$Name [object]$Arguments static [OpenAiChatFunctionCall] Parse([object]$rawFunctionCall) { $fc = [OpenAiChatFunctionCall]::new() $fc.Name = $rawFunctionCall.name #Write-Debug "$($rawFunctionCall.arguments), type=$($rawFunctionCall.arguments.GetType())" if($rawFunctionCall.arguments -ne "()") { try { $fc.Arguments = $rawFunctionCall.arguments | ConvertFrom-Json -AsHashtable } catch { Write-Debug "Failed to parse arguments: $($_)" } } #Write-Debug "Successfully parsed function call: $($fc | ConvertTo-Json -Depth 10)" return $fc } } class OpenAiChatMessage { [string]$Role [string]$Content [OpenAiChatFunctionCall]$FunctionCall = $null [OpenAiChatMessage[]]$AltChoices = @() OpenAiChatMessage() { } OpenAiChatMessage([string]$role, [string]$content) { $this.Role = $role $this.Content = $content } [object] AsRaw() { $raw = @{ "role" = $this.Role "content" = $this.Content } if($this.FunctionCall) { $raw.name = $this.FunctionCall.Name } return $raw } static [OpenAiChatMessage] ParseChoices([object[]]$rawMessages) { if($rawMessages.Count -eq 0) { return $null } $messages = @() foreach($rawMessage in $rawMessages) { $messages += [OpenAiChatMessage]::Parse($rawMessage) } $message = $messages[0] if($messages.Count -gt 1) { $message.AltChoices = $messages[1..($messages.Count-1)] } return $message } static [OpenAiChatMessage] Parse([object]$rawMessage) { $message = [OpenAiChatMessage]::new($rawMessage.role, $rawMessage.content) if($rawMessage.function_call) { $message.FunctionCall = [OpenAiChatFunctionCall]::Parse($rawMessage.function_call) } return $message } static [OpenAiChatMessage] FromUser([string]$message) { return [OpenAiChatMessage]::new("user", $message) } static [OpenAiChatMessage] FromFunction([string]$functionName, [object]$contentObject) { $contentJson = $contentObject | ConvertTo-Json -Depth 10 $message = [OpenAiChatMessage]::new("function", $contentJson) $message.FunctionCall = [OpenAiChatFunctionCall]::new() $message.FunctionCall.Name = $functionName return $message } static [OpenAiChatMessage] FromAssistant([string]$message) { return [OpenAiChatMessage]::new("assistant", $message) } } class OpenAiResponseReader { } class OpenAiStreamingResponseReader { # delegate to call on each delta } class OpenAiChat { [string]$AuthToken [string]$Model = "gpt-3.5-turbo" [decimal]$Temperature [decimal]$Top_p [int]$N [HttpClient]$httpClient [string]$httpContentType = "application/json" [bool]$_debug = $false [string]$Baseurl = "https://api.openai.com/v1/" [bool]$Stream = $false [object]$Functions [int]$Max_Tokens = 0 [object]$Response_Format OpenAiChat([string]$authToken) { $this.AuthToken = $authToken if(!$this.AuthToken) { throw "OpenAiChat requires an auth token (authToken argument on constructor)" } } [object] ChatCompletion([OpenAiChatMessage[]]$messages, [Func[HttpResponseMessage, object]]$success) { # translate OpenAiChatMessages to raw json-ready messages $rawMessages = @() $messages | ForEach-Object { $rawMessages += $_.AsRaw() } # construct body $body = @{ "model" = $this.Model "messages" = $rawMessages } if($this.Functions) { $body.functions = $this.Functions } # set optional parameters for the request if($this.Temperature) { $body.temperature = $this.Temperature } if($this.Top_p) { $body.top_p = $this.Top_p } if($this.N) { $body.n = $this.N } if($this.Stream) { $body.stream=$true } if($this.Max_Tokens -ne 0) { $body.max_tokens = $this.Max_Tokens } if($this.Response_Format) { $body.response_format = $this.Response_Format | ConvertTo-Json } return $this.InvokeRequestObject("chat/completions", $body, $success) } # call the api, requestObject is a object/hashtable with the full request body [object] InvokeRequestObject($url, [object]$requestBody, [Func[HttpResponseMessage, object]]$success) { # $useStream = $true $url = "$($this.Baseurl)$url" $headers = @{ "Authorization" = "Bearer $($this.AuthToken)" } $requestBodyJson = $requestBody | ConvertTo-Json -Depth 10 $response = $null if($this._debug) { Write-Debug "Request:`n$requestBodyJson" } if(!$this.httpClient) { $this.httpClient = [HttpClient]::new() } # create an HTTP request with a range header to receive only a specific chunk of data $request = [HttpRequestMessage]::new([HttpMethod]::Post, [Uri]::new($url)) foreach($key in $headers.Keys) { $request.Headers.Add($key, $headers[$key]) } if($this.Stream) { $request.Headers.Range = [RangeHeaderValue]::new(0, 1024) } $request.Content = [StringContent]::new($requestBodyJson, [Encoding]::UTF8, $this.httpContentType) # send the HTTP request and get the response try { $response = $this.httpClient.SendAsync($request, [HttpCompletionOption]::ResponseHeadersRead).Result if(!$response.IsSuccessStatusCode) { throw "An error occurred: $($response.StatusCode)" } if($success) { if($this._debug) { Write-Debug "Response:`n$($response | ConvertTo-Json -Depth 10)" } return $success.Invoke($response) } else { Write-Debug "Success handler not provided (is null)" } } catch { $failureBody = "" # try to get the response body try { $failureBody = $response.Content.ReadAsStringAsync().Result } catch { } if($this._debug) { [OutHelper]::NonCriticalError("Error while calling api", $_) [OutHelper]::NonCriticalError("Request:`n$requestBodyJson") [OutHelper]::NonCriticalError("Response:`n$failureBody") } if($failureBody.StartsWith("{")) { $failure = $failureBody | ConvertFrom-Json [OutHelper]::NonCriticalError("$($failure.error.message)") } else { [OutHelper]::NonCriticalError("$($failureBody)") } } return $null } [object] ApplyDelta($obj, $objDelta) { #Write-Debug "obj-before: $($obj | ConvertTo-Json -Depth 10)" foreach($nameValue in $objDelta.PSObject.Properties) { $key = $nameValue.Name $value = $nameValue.Value if($null -eq $value) { $value = "" } if(!$obj.$key) { $obj.$key = $value } else { if($value -is [PSObject]) { $obj.$key = $this.ApplyDelta($obj.$key, $value) } else { $obj.$key += $value } } } #Write-Debug "obj-after: $($obj | ConvertTo-Json -Depth 10)" return $obj } # calls the api and streams the response as it comes in [object] ReadAndStreamResponse($response) { $choices = @{} $streamReader = [StreamReader]::new($response.Content.ReadAsStreamAsync().Result) $firstContent = $true try { # read the response content as a stream of JSON data $dataPrefix = "data: " while (!$streamReader.EndOfStream) { # allow escape from streaming if ([Console]::KeyAvailable) { $key = [Console]::ReadKey($true) if($key.Key -eq [ConsoleKey]::Escape) { break } } # each line will begin with "data: ", the final line will be "data: [DONE]" $line = $streamReader.ReadLine() if (!$line.StartsWith($dataPrefix)) { continue } $line = $line.Substring($dataPrefix.Length) if($line -eq "[DONE]") { break } # [OutHelper]::Gpt($line) if($this._debug) { Write-Host "($line)" -ForegroundColor DarkGray -NoNewLine } $chunk = $line | ConvertFrom-Json if(!$chunk.choices -or $chunk.choices.Count -lt 1) { continue } # update the choices array with the new choice foreach($choice in $chunk.choices) { # $delta = $chunk.choices[0].delta # {"content":" you"} # $index = "i$($chunk.choices[0].index)" # 0 $delta = $choice.delta # eg. {"content":" you"} $index = "i$($choice.index)" # eg. 0 $c = $choices[$index] if($null -eq $c) { $c = $choices[$index] = @{} $c.content = "" } $contentPreDelta = $c.content $c = $choices[$index] = $this.ApplyDelta($c, $delta) # only stream first choice (index: 0) if($index -ne "i0") { continue } # output content-delta if any $contentDelta = $c.content.Substring($contentPreDelta.Length) if($contentDelta -ne "") { if($firstContent) { [OutHelper]::GptDelta("", $true) # writes GPT: $firstContent = $false } [OutHelper]::GptDelta($contentDelta, $false) } } } } catch { [OutHelper]::NonCriticalError("Error while streaming response", $_) } finally { $streamReader.Dispose() } if(!$firstContent) { [OutHelper]::GptDelta("`n", $false) } Write-Debug "Choices: $($choices | ConvertTo-Json -Depth 10)" return [OpenAiChatMessage]::ParseChoices($choices.Values) } [string] Ask([string]$message) { return $this.GetAnswer(@([OpenAiChatMessage]::ToAssistant($message))).Content } [object] ReadResponseAsObject([HttpResponseMessage]$response) { if($this.PsClassic()) { return [HashTable]($response.Content.ReadAsStringAsync().Result | ConvertFrom-Json) } else { return $response.Content.ReadAsStringAsync().Result | ConvertFrom-Json -AsHashtable } } [OpenAiChatMessage] ReadChoices([HttpResponseMessage]$response) { $res = $this.ReadResponseAsObject($response) # Write-Debug $($res | ConvertTo-Json -Depth 10) if($null -eq $res) { return $null } return [OpenAiChatMessage]::ParseChoices($res.choices.message) } [OpenAiChatMessage] GetAnswer([OpenAiChatMessage[]]$messages) { $cb = if($this.Stream) { # this is purposely kept clumsy to support PS 5.1 (which may be removed in the future) [System.Func[HttpResponseMessage, object]]{param($response) return $this.ReadAndStreamResponse($response) } } else { [System.Func[HttpResponseMessage, object]]{param($response) return $this.ReadChoices($response) } } $message = $this.ChatCompletion($messages, $cb) # Write-Debug "$($message.AltChoices.Count) alt choices" return $message } [bool] PsClassic() { return (Get-Host).Version.Major -lt 6 } } |