Web APIs: `File` and `FormData` (#1056)

1 files changed, 107 insertions, 0 deletions

diff --git a/js/form_data.ts b/js/form_data.ts
new file mode 100644
index 000000000..662643520
--- /dev/null
+++ b/js/form_data.ts
@@ -0,0 +1,107 @@
+// Copyright 2018 the Deno authors. All rights reserved. MIT license.
+import * as domTypes from "./dom_types";
+import * as blob from "./blob";
+import * as file from "./file";
+import { DomIterableMixin } from "./mixins/dom_iterable";
+
+const dataSymbol = Symbol("data");
+
+class FormDataBase {
+  private [dataSymbol]: Array<[string, domTypes.FormDataEntryValue]> = [];
+
+  /** Appends a new value onto an existing key inside a `FormData`
+   * object, or adds the key if it does not already exist.
+   *
+   *       formData.append('name', 'first');
+   *       formData.append('name', 'second');
+   */
+  append(name: string, value: string): void;
+  append(name: string, value: blob.DenoBlob, filename?: string): void;
+  append(name: string, value: string | blob.DenoBlob, filename?: string): void {
+    if (value instanceof blob.DenoBlob) {
+      const dfile = new file.DenoFile([value], filename || name);
+      this[dataSymbol].push([name, dfile]);
+    } else {
+      this[dataSymbol].push([name, String(value)]);
+    }
+  }
+
+  /** Deletes a key/value pair from a `FormData` object.
+   *
+   *       formData.delete('name');
+   */
+  delete(name: string): void {
+    let i = 0;
+    while (i < this[dataSymbol].length) {
+      if (this[dataSymbol][i][0] === name) {
+        this[dataSymbol].splice(i, 1);
+      } else {
+        i++;
+      }
+    }
+  }
+
+  /** Returns an array of all the values associated with a given key
+   * from within a `FormData`.
+   *
+   *       formData.getAll('name');
+   */
+  getAll(name: string): domTypes.FormDataEntryValue[] {
+    const values = [];
+    for (const entry of this[dataSymbol]) {
+      if (entry[0] === name) {
+        values.push(entry[1]);
+      }
+    }
+
+    return values;
+  }
+
+  /** Returns the first value associated with a given key from within a
+   * `FormData` object.
+   *
+   *       formData.get('name');
+   */
+  get(name: string): domTypes.FormDataEntryValue | null {
+    for (const entry of this[dataSymbol]) {
+      if (entry[0] === name) {
+        return entry[1];
+      }
+    }
+
+    return null;
+  }
+
+  /** Returns a boolean stating whether a `FormData` object contains a
+   * certain key/value pair.
+   *
+   *       formData.has('name');
+   */
+  has(name: string): boolean {
+    return this[dataSymbol].some(entry => entry[0] === name);
+  }
+
+  /** Sets a new value for an existing key inside a `FormData` object, or
+   * adds the key/value if it does not already exist.
+   *
+   *       formData.set('name', 'value');
+   */
+  set(name: string, value: string): void;
+  set(name: string, value: blob.DenoBlob, filename?: string): void;
+  set(name: string, value: string | blob.DenoBlob, filename?: string): void {
+    this.delete(name);
+    if (value instanceof blob.DenoBlob) {
+      const dfile = new file.DenoFile([value], filename || name);
+      this[dataSymbol].push([name, dfile]);
+    } else {
+      this[dataSymbol].push([name, String(value)]);
+    }
+  }
+}
+
+// tslint:disable-next-line:variable-name
+export const FormData = DomIterableMixin<
+  string,
+  domTypes.FormDataEntryValue,
+  typeof FormDataBase
+>(FormDataBase, dataSymbol);