add support for FormData

index.js

@@ -10,6 +10,33 @@ function md5(str) {
   return crypto.createHash('md5').update(str).digest('hex');
 }
 
+function getFormDataCacheKey(formData) {
+  const cacheKey = { ...formData };
+
+  if (typeof formData.getBoundary === 'function') {
+    const boundary = formData.getBoundary();
+
+    // eslint-disable-next-line no-underscore-dangle
+    delete cacheKey._boundary;
+
+    // eslint-disable-next-line no-underscore-dangle
+    if (Array.isArray(cacheKey._streams)) {
+      const boundaryReplaceRegex = new RegExp(boundary, 'g');
+
+      // eslint-disable-next-line no-underscore-dangle
+      cacheKey._streams = cacheKey._streams.map((s) => {
+        if (typeof s === 'string') {
+          return s.replace(boundaryReplaceRegex, '');
+        }
+
+        return s;
+      });
+    }
+  }
+
+  return cacheKey;
+}
+
 function getBodyCacheKeyJson(body) {
   if (!body) {
     return body;
@@ -19,6 +46,8 @@ function getBodyCacheKeyJson(body) {
     return body.toString();
   } if (body instanceof fs.ReadStream) {
     return body.path;
+  } if (body.toString && body.toString() === '[object FormData]') {
+    return getFormDataCacheKey(body);
   }
 
   throw new Error('Unsupported body type');

package-lock.json

@@ -156,6 +156,12 @@
       "integrity": "sha512-+Ryf6g3BKoRc7jfp7ad8tM4TtMiaWvbF/1/sQcZPkkS7ag3D5nMBCe2UfOTONtAkaG0tO0ij3C5Lwmf1EiyjHg==",
       "dev": true
     },
+    "asynckit": {
+      "version": "0.4.0",
+      "resolved": "https://registry.npmjs.org/asynckit/-/asynckit-0.4.0.tgz",
+      "integrity": "sha1-x57Zf380y48robyXkLzDZkdLS3k=",
+      "dev": true
+    },
     "balanced-match": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/balanced-match/-/balanced-match-1.0.0.tgz",
@@ -310,6 +316,15 @@
       "integrity": "sha1-p9BVi9icQveV3UIyj3QIMcpTvCU=",
       "dev": true
     },
+    "combined-stream": {
+      "version": "1.0.8",
+      "resolved": "https://registry.npmjs.org/combined-stream/-/combined-stream-1.0.8.tgz",
+      "integrity": "sha512-FQN4MRfuJeHf7cBbBMJFXhKSDq+2kAArBlmRBvcvFE5BB1HZKXtSFASDhdlz9zOYwxh8lDdnvmMOe/+5cdoEdg==",
+      "dev": true,
+      "requires": {
+        "delayed-stream": "~1.0.0"
+      }
+    },
     "compare-versions": {
       "version": "3.6.0",
       "resolved": "https://registry.npmjs.org/compare-versions/-/compare-versions-3.6.0.tgz",
@@ -418,6 +433,12 @@
         "object-keys": "^1.0.12"
       }
     },
+    "delayed-stream": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/delayed-stream/-/delayed-stream-1.0.0.tgz",
+      "integrity": "sha1-3zrhmayt+31ECqrgsp4icrJOxhk=",
+      "dev": true
+    },
     "diff": {
       "version": "4.0.2",
       "resolved": "https://registry.npmjs.org/diff/-/diff-4.0.2.tgz",
@@ -829,6 +850,17 @@
       "integrity": "sha512-r5wGx7YeOwNWNlCA0wQ86zKyDLMQr+/RB8xy74M4hTphfmjlijTSSXGuH8rnvKZnfT9i+75zmd8jcKdMR4O6jA==",
       "dev": true
     },
+    "form-data": {
+      "version": "3.0.0",
+      "resolved": "https://registry.npmjs.org/form-data/-/form-data-3.0.0.tgz",
+      "integrity": "sha512-CKMFDglpbMi6PyN+brwB9Q/GOw0eAnsrEZDgcsH5Krhz5Od/haKHAX0NmQfha2zPPz0JpWzA7GJHGSnvCRLWsg==",
+      "dev": true,
+      "requires": {
+        "asynckit": "^0.4.0",
+        "combined-stream": "^1.0.8",
+        "mime-types": "^2.1.12"
+      }
+    },
     "fs.realpath": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/fs.realpath/-/fs.realpath-1.0.0.tgz",
@@ -1433,6 +1465,21 @@
         }
       }
     },
+    "mime-db": {
+      "version": "1.44.0",
+      "resolved": "https://registry.npmjs.org/mime-db/-/mime-db-1.44.0.tgz",
+      "integrity": "sha512-/NOTfLrsPBVeH7YtFPgsVWveuL+4SjjYxaQ1xtM1KMFj7HdxlBlxeyNLzhyJVx7r4rZGJAZ/6lkKCitSc/Nmpg==",
+      "dev": true
+    },
+    "mime-types": {
+      "version": "2.1.27",
+      "resolved": "https://registry.npmjs.org/mime-types/-/mime-types-2.1.27.tgz",
+      "integrity": "sha512-JIhqnCasI9yD+SsmkquHBxTSEuZdQX5BuQnS2Vc7puQQQ+8yiP5AY5uWhpdv4YL4VM5c6iliiYWPgJ/nJQLp7w==",
+      "dev": true,
+      "requires": {
+        "mime-db": "1.44.0"
+      }
+    },
     "mimic-fn": {
       "version": "2.1.0",
       "resolved": "https://registry.npmjs.org/mimic-fn/-/mimic-fn-2.1.0.tgz",

package.json

@@ -29,6 +29,7 @@
     "eslint": "^6.8.0",
     "eslint-config-airbnb-base": "^14.1.0",
     "eslint-plugin-import": "^2.20.2",
+    "form-data": "^3.0.0",
     "husky": "^4.3.0",
     "mocha": "^8.2.1",
     "rimraf": "^3.0.2"

test/tests.js

@@ -1,4 +1,5 @@
 const fs = require('fs');
+const FormData = require('form-data');
 const assert = require('assert');
 const rimraf = require('rimraf');
 const path = require('path');
@@ -163,6 +164,34 @@ describe('Cache tests', function() {
     res = await fetch(TWO_HUNDRED_URL, post(s1));
     assert.strictEqual(res.fromCache, true);
   });
+
+  it('Gives different form data different cache keys', async function() {
+    const data1 = new FormData();
+    data1.append('a', 'a');
+
+    const data2 = new FormData();
+    data2.append('b', 'b');
+
+    res = await fetch(TWO_HUNDRED_URL, post(data1));
+    assert.strictEqual(res.fromCache, false);
+
+    res = await fetch(TWO_HUNDRED_URL, post(data2));
+    assert.strictEqual(res.fromCache, false);
+  });
+
+  it('Gives same form data same cache keys', async function() {
+    const data1 = new FormData();
+    data1.append('a', 'a');
+
+    const data2 = new FormData();
+    data2.append('a', 'a');
+
+    res = await fetch(TWO_HUNDRED_URL, post(data1));
+    assert.strictEqual(res.fromCache, false);
+
+    res = await fetch(TWO_HUNDRED_URL, post(data2));
+    assert.strictEqual(res.fromCache, true);
+  });
 }).timeout(10000);
 
 describe('Data tests', function() {