title: Deleting all documents in Firestore collection
body: <p>I'm looking for a way to clear an entire collection. I saw that there is a batch update option, but that would require me to know all of the document IDs in the collection. </p>
  
  <p>I'm looking for a way to simply delete every document in the collection.</p>
  
  <p>Thanks!</p>
  
  <p>Edit: Answer below is correct, I used the following:</p>
  
  <pre><code>  func delete(collection: CollectionReference, batchSize: Int = 100) {
      // Limit query to avoid out-of-memory errors on large collections.
      // When deleting a collection guaranteed to fit in memory, batching can be avoided entirely.
      collection.limit(to: batchSize).getDocuments { (docset, error) in
        // An error occurred.
        let docset = docset
  
        let batch = collection.firestore.batch()
        docset?.documents.forEach { batch.deleteDocument($0.reference) }
  
        batch.commit {_ in
          self.delete(collection: collection, batchSize: batchSize)
        }
      }
    }
  </code></pre>