Use https proxy agent (#132)

package.json

@@ -35,7 +35,9 @@
     "@slack/web-api": "^6.7.2",
     "axios": "^0.27.2",
     "flat": "^5.0.2",
-    "markup-js": "^1.5.21"
+    "https-proxy-agent": "^5.0.1",
+    "markup-js": "^1.5.21",
+    "whatwg-url": "^11.0.0"
   },
   "devDependencies": {
     "@vercel/ncc": "^0.34.0",

src/slack-send.js

@@ -5,6 +5,8 @@ const axios = require('axios');
 const { promises: fs } = require('fs');
 const path = require('path');
 const markup = require('markup-js');
+const HttpsProxyAgent = require('https-proxy-agent');
+const { parseURL } = require('whatwg-url');
 
 const SLACK_WEBHOOK_TYPES = {
   WORKFLOW_TRIGGER: 'WORKFLOW_TRIGGER',
@@ -106,8 +108,24 @@ module.exports = async function slackSend(core) {
         payload = flatPayload;
       }
 
+      const axiosOpts = {};
       try {
-        await axios.post(webhookUrl, payload);
+        if (parseURL(webhookUrl).scheme === 'https') {
+          const httpsProxy = process.env.HTTPS_PROXY || process.env.https_proxy || '';
+          if (httpsProxy && parseURL(httpsProxy).scheme === 'http') {
+            const httpsProxyAgent = new HttpsProxyAgent(httpsProxy);
+            axiosOpts.httpsAgent = httpsProxyAgent;
+
+            // Use configured tunnel above instead of default axios proxy setup from env vars
+            axiosOpts.proxy = false;
+          }
+        }
+      } catch (err) {
+        console.log('failed to configure https proxy agent for http proxy. Using default axios configuration');
+      }
+
+      try {
+        await axios.post(webhookUrl, payload, axiosOpts);
       } catch (err) {
         console.log('axios post failed, double check the payload being sent includes the keys Slack expects');
         console.log(payload);

test/slack-send-test.js

@@ -187,6 +187,33 @@ describe('slack-send', () => {
         await slackSend(fakeCore);
         assert(AxiosMock.post.calledWith('https://someurl', payload));
       });
+      describe('proxy config', () => {
+        beforeEach(() => {
+          delete process.env.HTTPS_PROXY;
+        });
+        it('should use https proxy agent when proxy uses HTTP', async () => {
+          process.env.HTTPS_PROXY = 'http://test.proxy:8080/';
+          await slackSend(fakeCore);
+          assert(AxiosMock.post.calledWith('https://someurl', payload, sinon.match.has('httpsAgent').and(sinon.match.has('proxy'))));
+        });
+        it('should use default axios config when no proxy set', async () => {
+          await slackSend(fakeCore);
+          assert(AxiosMock.post.calledWithExactly('https://someurl', payload, {}));
+        });
+        it('should use default axios config when proxy uses HTTPS', async () => {
+          process.env.HTTPS_PROXY = 'https://test.proxy:8080/';
+          await slackSend(fakeCore);
+          assert(AxiosMock.post.calledWithExactly('https://someurl', payload, {}));
+        });
+        it('should use default axios config when proxy URL is invalid', async () => {
+          process.env.HTTPS_PROXY = 'invalid string';
+          const consoleSpy = sinon.spy(console, 'log');
+          await slackSend(fakeCore);
+
+          assert(consoleSpy.calledWith('failed to configure https proxy agent for http proxy. Using default axios configuration'));
+          assert(AxiosMock.post.calledWithExactly('https://someurl', payload, {}));
+        });
+      });
     });
     describe('sad path', () => {
       it('should set an error if the POST to the webhook fails without a response', async () => {