bf(UTAPI-113): Support POST based auth in Vault mock

Author: tmacro

tests/utils/mock/Vault.js

@@ -19,11 +19,29 @@ class Vault {
             return;
         }
 
-        const reqCtx = JSON.parse(query.requestContext);
-        if (reqCtx.headers['x-amz-security-token'] && !query.securityToken) {
-            res.writeHead(400, { 'Content-Type': 'application/json' });
-            res.write(JSON.stringify({ code: 'InvalidSecurityToken', message: 'Security token is missing' }));
-            res.end();
+        if (req.method == 'GET') {
+            const reqCtx = JSON.parse(query.requestContext);
+            if (reqCtx.headers['x-amz-security-token'] && !query.securityToken) {
+                res.writeHead(400, { 'Content-Type': 'application/json' });
+                res.write(JSON.stringify({ code: 'InvalidSecurityToken', message: 'Security token is missing' }));
+                res.end();
+                return;
+            }
+        } else if (req.method == 'POST') {
+            const body = [];
+            req.on('data', chunk => {
+                body.push(chunk);
+            });
+            req.on('end', () => {
+                const bodyString = Buffer.concat(body).toString();
+                const bodyJson = JSON.parse(bodyString);
+                if (bodyJson.requestContext.headers['x-amz-security-token'] && !query.securityToken) {
+                    res.writeHead(400, { 'Content-Type': 'application/json' });
+                    res.write(JSON.stringify({ code: 'InvalidSecurityToken', message: 'Security token is missing' }));
+                    res.end();
+                    return;
+                }
+            });
             return;
         }