Azure OpenAI GPT-4 / ChatGPT API

A simple RESTful API of GPT-4 / ChatGPT with Azure OpenAI Service, build with TypeScript and Node.js Express

⚠️ Design for testing and internal use only. ⚠️

Features

• Base on Azure OpenAI Service REST API
• One endpoint for simple usage
• Flexible and easily extensible for future development
• Logit bias & function call are not supported yet
• RESTful API structure
• Ready for use with PM2
• Build with TypeScript, Node.js, Express

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Config

Config Name	Required?	Default Value	Description
HTTP_PORT	✔️	80	The HTTP port number of API
HTTPS_PORT	✅	443	The HTTPS port number of API (if ENABLE_SSL=true)
ENABLE_SSL	✅	false	Use HTTPS or not
SSL_CERT	✅	N/A	The SSL certificate file path (if ENABLE_SSL=true)
SSL_KEY	✅	N/A	The SSL private key file path (if ENABLE_SSL=true)
ENDPOINT	✔️	N/A	The Azure OpenAI Service endpoint URL
DEPLOYMENT_NAME	✔️	N/A	The deployment name of Azure OpenAI Service
API_VERSION	✔️	N/A	The API version of Azure OpenAI Service
KEY	✔️	N/A	The API key for accessing the Azure OpenAI Service
temperature	❌	1 (A)	The default sampling temperature value for GPT model output
top_p	❌	N/A	The default top_p value for GPT model output
n	❌	1 (A)	The default number of chat completion choices to generate for GPT model output
stream	❌	false (A)	The default boolean value indicating whether to stream GPT model output
stop	❌	null (A)	The default sequences where the GPT model stop output
max_tokens	❌	inf (A)	The default maximum number of tokens allowed for GPT model output
presence_penalty	❌	0 (A)	The default presence penalty number for GPT model output
frequency_penalty	❌	0 (A)	The default frequency penalty number for GPT model output
user	❌	N/A	The unique identifier of user for Azure OpenAI

*(A): Azure OpenAI Default value (may be changed by Azure OpenAI Service)

**For the details of GPT options, you may refer to the API doc below or the Official document

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API doc

Chat Completions

• Request Method: POST
• API Endpoint: /v1/gpt/chat

Request Body

Only prompt/userPrompt is required, all other params are optional.

Param Name	Type	Default Value	Description
prompt	string	N/A	Alias of userPrompt
userPrompt	string	N/A	User prompt input for chat completions
systemPrompt	string	N/A	System prompt to instruct or set the behavior of the assistant
assistantPrompt	string	N/A	Assistant prompt provides responses to system-instructed, user-prompted input
temperature	number	1 (A)	What sampling temperature to use, between 0 and 2. Higher values like 0.8 will make the output more random, while lower values like 0.2 will make it more focused and deterministic.\nWe generally recommend altering this or top_p but not both.
top_p	number	1 (A)	An alternative to sampling with temperature, called nucleus sampling, where the model considers the results of the tokens with top_p probability mass. So 0.1 means only the tokens comprising the top 10% probability mass are considered. We generally recommend altering this or temperature but not both.
n	integer	1 (A)	How many chat completion choices to generate for each input message.
stream	boolean	false (A)	If set, partial message deltas will be sent, like in ChatGPT. Tokens will be sent as data-only server-sent events as they become available, with the stream terminated by a data: [DONE] message."
stop	string / array	null (A)	Up to 4 sequences where the API will stop generating further tokens.
max_tokens	integer	inf (A)	The maximum number of tokens allowed for the generated answer. By default, the number of tokens the model can return will be (4096 - prompt tokens).
presence_penalty	number	0 (A)	Number between -2.0 and 2.0. Positive values penalize new tokens based on whether they appear in the text so far, increasing the model's likelihood to talk about new topics.
frequency_penalty	number	0 (A)	Number between -2.0 and 2.0. Positive values penalize new tokens based on their existing frequency in the text so far, decreasing the model's likelihood to repeat the same line verbatim.
user	string	N/A	A unique identifier representing your end-user, which can help Azure OpenAI to monitor and detect abuse.

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Build & Start

1. You must have enabled the Azure AI services - Azure OpenAI of your Azure account first
2. git clone https://github.com/jasonfoknxu/azure-openai-chatgpt-api to download the source code
3. yarn or npm install to install all the dependencies
4. Copy the sample.env file and rename as .env
5. Edit the config in the .env file
6. yarn run build or npm run build to compile the scripts
7. yarn start or npm start to start the API server

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Reference

https://learn.microsoft.com/en-us/azure/ai-services/openai/reference