Migrate from Azure OpenAI to Railwail

Before (Azure OpenAI):

import { AzureOpenAI } from "openai";

const azure = new AzureOpenAI({
  apiKey: process.env.AZURE_OPENAI_API_KEY,
  endpoint: "https://my-resource.openai.azure.com",
  apiVersion: "2025-01-01",
  deployment: "my-gpt4o-deployment",
});

const res = await azure.chat.completions.create({
  model: "my-gpt4o-deployment",  // Same as deployment name
  messages: [{ role: "user", content: "Hello" }],
});

After (Railwail):

import OpenAI from "openai";

const client = new OpenAI({
  apiKey: process.env.RAILWAIL_API_KEY,
  baseURL: "https://railwail.com/api/v1",
});

const res = await client.chat.completions.create({
  model: "gpt-4o",  // Real model ID, no deployment name
  messages: [{ role: "user", content: "Hello" }],
});

from openai import OpenAI

client = OpenAI(
    api_key=os.environ["RAILWAIL_API_KEY"],
    base_url="https://railwail.com/api/v1",
)

resp = client.chat.completions.create(
    model="gpt-4o",
    messages=[{"role": "user", "content": "Hello"}],
)
print(resp.choices[0].message.content)

Before (Azure):

curl https://my-resource.openai.azure.com/openai/deployments/my-gpt4o-deployment/chat/completions?api-version=2025-01-01 \
  -H "api-key: $AZURE_OPENAI_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"messages":[{"role":"user","content":"Hello"}]}'

After (Railwail):

curl https://railwail.com/api/v1/chat/completions \
  -H "Authorization: Bearer $RAILWAIL_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model":"gpt-4o","messages":[{"role":"user","content":"Hello"}]}'

Notice the URL is no longer parameterised by resource and deployment, and you use the standard Authorization: Bearer header instead of api-key.