1 files changed, 76 insertions, 0 deletions
diff --git a/node_modules/mongodb/lib/write_concern.js b/node_modules/mongodb/lib/write_concern.js
new file mode 100644
index 0000000..1ba0380
--- /dev/null
+++ b/node_modules/mongodb/lib/write_concern.js
@@ -0,0 +1,76 @@
+'use strict';
+
+const kWriteConcernKeys = new Set(['w', 'wtimeout', 'j', 'fsync']);
+
+/**
+ * The **WriteConcern** class is a class that represents a MongoDB WriteConcern.
+ * @class
+ * @property {(number|string)} w The write concern
+ * @property {number} wtimeout The write concern timeout
+ * @property {boolean} j The journal write concern
+ * @property {boolean} fsync The file sync write concern
+ * @see https://docs.mongodb.com/manual/reference/write-concern/index.html
+ */
+class WriteConcern {
+  /**
+   * Constructs a WriteConcern from the write concern properties.
+   * @param {(number|string)} [w] The write concern
+   * @param {number} [wtimeout] The write concern timeout
+   * @param {boolean} [j] The journal write concern
+   * @param {boolean} [fsync] The file sync write concern
+   */
+  constructor(w, wtimeout, j, fsync) {
+    if (w != null) {
+      this.w = w;
+    }
+    if (wtimeout != null) {
+      this.wtimeout = wtimeout;
+    }
+    if (j != null) {
+      this.j = j;
+    }
+    if (fsync != null) {
+      this.fsync = fsync;
+    }
+  }
+
+  /**
+   * Construct a WriteConcern given an options object.
+   *
+   * @param {object} options The options object from which to extract the write concern.
+   * @return {WriteConcern}
+   */
+  static fromOptions(options) {
+    if (
+      options == null ||
+      (options.writeConcern == null &&
+        options.w == null &&
+        options.wtimeout == null &&
+        options.j == null &&
+        options.fsync == null)
+    ) {
+      return;
+    }
+
+    if (options.writeConcern) {
+      if (typeof options.writeConcern === 'string') {
+        return new WriteConcern(options.writeConcern);
+      }
+
+      if (!Object.keys(options.writeConcern).some(key => kWriteConcernKeys.has(key))) {
+        return;
+      }
+
+      return new WriteConcern(
+        options.writeConcern.w,
+        options.writeConcern.wtimeout,
+        options.writeConcern.j,
+        options.writeConcern.fsync
+      );
+    }
+
+    return new WriteConcern(options.w, options.wtimeout, options.j, options.fsync);
+  }
+}
+
+module.exports = WriteConcern;