feat: get access token & refresh tokens for server type SASJS

src/auth/getAccessTokenForViya.ts

@@ -0,0 +1,53 @@
+import { SasAuthResponse } from '@sasjs/utils/types'
+import { prefixMessage } from '@sasjs/utils/error'
+import * as NodeFormData from 'form-data'
+import { RequestClient } from '../request/RequestClient'
+
+/**
+ * Exchanges the auth code for an access token for the given client.
+ * @param requestClient - the pre-configured HTTP request client
+ * @param clientId - the client ID to authenticate with.
+ * @param clientSecret - the client secret to authenticate with.
+ * @param authCode - the auth code received from the server.
+ */
+export async function getAccessTokenForViya(
+  requestClient: RequestClient,
+  clientId: string,
+  clientSecret: string,
+  authCode: string
+): Promise<SasAuthResponse> {
+  const url = '/SASLogon/oauth/token'
+  let token
+  if (typeof Buffer === 'undefined') {
+    token = btoa(clientId + ':' + clientSecret)
+  } else {
+    token = Buffer.from(clientId + ':' + clientSecret).toString('base64')
+  }
+  const headers = {
+    Authorization: 'Basic ' + token
+  }
+
+  let formData
+  if (typeof FormData === 'undefined') {
+    formData = new NodeFormData()
+  } else {
+    formData = new FormData()
+  }
+  formData.append('grant_type', 'authorization_code')
+  formData.append('code', authCode)
+
+  const authResponse = await requestClient
+    .post(
+      url,
+      formData,
+      undefined,
+      'multipart/form-data; boundary=' + (formData as any)._boundary,
+      headers
+    )
+    .then((res) => res.result as SasAuthResponse)
+    .catch((err) => {
+      throw prefixMessage(err, 'Error while getting access token. ')
+    })
+
+  return authResponse
+}