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Firestoreのすべてのサブコレクションとネストされたサブコレクションを含むドキュメントを削除する

すべてのコレクションとネストされたサブコレクションを含むドキュメントを削除するにはどうすればよいですか? (機能環境内)

RTDBでref.child('../someNode).setValue(null)を実行すると、目的の動作が完了します。

望みの削除動作を実現できる2つの方法を考えることができますが、どちらも非常に恐ろしい欠点があります。

  1. すべてのドキュメントをスパイダーし、バッチで削除する「スーパー」機能を作成します。この関数は複雑で、変更に対して脆弱であり、実行時間が長くなる可能性があります。

  2. 各ドキュメントタイプに「onDelete」トリガーを追加し、直接のサブコレクションを削除します。ルートドキュメントでdeleteを呼び出すと、削除呼び出しは「ツリー」に伝播します。これは遅く、拡張性がひどく、関数実行の膨大な負荷のためにコストがかかります。

「GROUP」とそのすべての子を削除する必要があると想像してください。 #1では非常に混oticとし、#2では高価です(ドキュメントごとに1つの関数呼び出し)

groups > GROUP > projects > PROJECT > files > FILE > assets > ASSET
                                                   > urls > URL
                                    > members > MEMBER
               > questions > QUESTION > answers > ANSWER > replies > REPLY
                                      > comments > COMMENT
               > resources > RESOURCE > submissions > SUBMISSION
                                      > requests > REQUEST

文書とそのすべてのネストされたサブコレクションを削除するための優れた/好まれる/きれいな方法はありますか?

コンソールから実行できることを考えれば、それは可能であるべきです。

21
Linxy

firebaseのドキュメントによると:
https://firebase.google.com/docs/firestore/solutions/delete-collections
ネストされたサブコレクションを使用したコレクションの削除は、サーバー側のnode-JSを使用して簡単かつ適切に実行できます。

const client = require('firebase-tools');
await client.firestore
      .delete(collectionPath, {
        project: process.env.GCLOUD_PROJECT,
        recursive: true,
        yes: true
      }); 
2
Oleg Bondarenko

残念ながら、あなたの分析はスポットオンであり、実際、このユースケースは多くの儀式を必要とします。公式ドキュメントによると、firestoreの単一のshotでの深い削除のサポートはありません。クライアントライブラリも rest-apicliツール。

cliはオープンソースであり、その実装は次のとおりです。 https://github.com/firebase/firebase-tools/blob/master/src/firestore/delete.js 。基本的に、オプション1を実装しました。質問で説明したので、そこからインスピレーションを得ることができます。

オプション1と2はどちらも理想的な状況とはほど遠いものであり、ソリューションを100%信頼できるものにするためには、削除タスクでpersistentキューを維持する必要があります。長時間実行中の手順でエラーが発生すると、システムが不明確な状態のままになります。

再帰的なクラウド関数呼び出しが非常に簡単に間違っている可能性があるため、未加工のオプション2を使用することはお勧めしません。制限。

リンクが変更された場合、 https://github.com/firebase/firebase-tools/blob/master/src/firestore/delete.js の完全なソースの下:

"use strict";

var clc = require("cli-color");
var ProgressBar = require("progress");

var api = require("../api");
var firestore = require("../gcp/firestore");
var FirebaseError = require("../error");
var logger = require("../logger");
var utils = require("../utils");

/**
 * Construct a new Firestore delete operation.
 *
 * @constructor
 * @param {string} project the Firestore project ID.
 * @param {string} path path to a document or collection.
 * @param {boolean} options.recursive true if the delete should be recursive.
 * @param {boolean} options.shallow true if the delete should be shallow (non-recursive).
 * @param {boolean} options.allCollections true if the delete should universally remove all collections and docs.
 */
function FirestoreDelete(project, path, options) {
  this.project = project;
  this.path = path;
  this.recursive = Boolean(options.recursive);
  this.shallow = Boolean(options.shallow);
  this.allCollections = Boolean(options.allCollections);

  // Remove any leading or trailing slashes from the path
  if (this.path) {
    this.path = this.path.replace(/(^\/+|\/+$)/g, "");
  }

  this.isDocumentPath = this._isDocumentPath(this.path);
  this.isCollectionPath = this._isCollectionPath(this.path);

  this.allDescendants = this.recursive;
  this.parent = "projects/" + project + "/databases/(default)/documents";

  // When --all-collections is passed any other flags or arguments are ignored
  if (!options.allCollections) {
    this._validateOptions();
  }
}

/**
 * Validate all options, throwing an exception for any fatal errors.
 */
FirestoreDelete.prototype._validateOptions = function() {
  if (this.recursive && this.shallow) {
    throw new FirebaseError("Cannot pass recursive and shallow options together.");
  }

  if (this.isCollectionPath && !this.recursive && !this.shallow) {
    throw new FirebaseError("Must pass recursive or shallow option when deleting a collection.");
  }

  var pieces = this.path.split("/");

  if (pieces.length === 0) {
    throw new FirebaseError("Path length must be greater than zero.");
  }

  var hasEmptySegment = pieces.some(function(piece) {
    return piece.length === 0;
  });

  if (hasEmptySegment) {
    throw new FirebaseError("Path must not have any empty segments.");
  }
};

/**
 * Determine if a path points to a document.
 *
 * @param {string} path a path to a Firestore document or collection.
 * @return {boolean} true if the path points to a document, false
 * if it points to a collection.
 */
FirestoreDelete.prototype._isDocumentPath = function(path) {
  if (!path) {
    return false;
  }

  var pieces = path.split("/");
  return pieces.length % 2 === 0;
};

/**
 * Determine if a path points to a collection.
 *
 * @param {string} path a path to a Firestore document or collection.
 * @return {boolean} true if the path points to a collection, false
 * if it points to a document.
 */
FirestoreDelete.prototype._isCollectionPath = function(path) {
  if (!path) {
    return false;
  }

  return !this._isDocumentPath(path);
};

/**
 * Construct a StructuredQuery to find descendant documents of a collection.
 *
 * See:
 * https://firebase.google.com/docs/firestore/reference/rest/v1beta1/StructuredQuery
 *
 * @param {boolean} allDescendants true if subcollections should be included.
 * @param {number} batchSize maximum number of documents to target (limit).
 * @param {string=} startAfter document name to start after (optional).
 * @return {object} a StructuredQuery.
 */
FirestoreDelete.prototype._collectionDescendantsQuery = function(
  allDescendants,
  batchSize,
  startAfter
) {
  var nullChar = String.fromCharCode(0);

  var startAt = this.parent + "/" + this.path + "/" + nullChar;
  var endAt = this.parent + "/" + this.path + nullChar + "/" + nullChar;

  var where = {
    compositeFilter: {
      op: "AND",
      filters: [
        {
          fieldFilter: {
            field: {
              fieldPath: "__name__",
            },
            op: "GREATER_THAN_OR_EQUAL",
            value: {
              referenceValue: startAt,
            },
          },
        },
        {
          fieldFilter: {
            field: {
              fieldPath: "__name__",
            },
            op: "LESS_THAN",
            value: {
              referenceValue: endAt,
            },
          },
        },
      ],
    },
  };

  var query = {
    structuredQuery: {
      where: where,
      limit: batchSize,
      from: [
        {
          allDescendants: allDescendants,
        },
      ],
      select: {
        fields: [{ fieldPath: "__name__" }],
      },
      orderBy: [{ field: { fieldPath: "__name__" } }],
    },
  };

  if (startAfter) {
    query.structuredQuery.startAt = {
      values: [{ referenceValue: startAfter }],
      before: false,
    };
  }

  return query;
};

/**
 * Construct a StructuredQuery to find descendant documents of a document.
 * The document itself will not be included
 * among the results.
 *
 * See:
 * https://firebase.google.com/docs/firestore/reference/rest/v1beta1/StructuredQuery
 *
 * @param {boolean} allDescendants true if subcollections should be included.
 * @param {number} batchSize maximum number of documents to target (limit).
 * @param {string=} startAfter document name to start after (optional).
 * @return {object} a StructuredQuery.
 */
FirestoreDelete.prototype._docDescendantsQuery = function(allDescendants, batchSize, startAfter) {
  var query = {
    structuredQuery: {
      limit: batchSize,
      from: [
        {
          allDescendants: allDescendants,
        },
      ],
      select: {
        fields: [{ fieldPath: "__name__" }],
      },
      orderBy: [{ field: { fieldPath: "__name__" } }],
    },
  };

  if (startAfter) {
    query.structuredQuery.startAt = {
      values: [{ referenceValue: startAfter }],
      before: false,
    };
  }

  return query;
};

/**
 * Query for a batch of 'descendants' of a given path.
 *
 * For document format see:
 * https://firebase.google.com/docs/firestore/reference/rest/v1beta1/Document
 *
 * @param {boolean} allDescendants true if subcollections should be included,
 * @param {number} batchSize the maximum size of the batch.
 * @param {string=} startAfter the name of the document to start after (optional).
 * @return {Promise<object[]>} a promise for an array of documents.
 */
FirestoreDelete.prototype._getDescendantBatch = function(allDescendants, batchSize, startAfter) {
  var url;
  var body;
  if (this.isDocumentPath) {
    url = this.parent + "/" + this.path + ":runQuery";
    body = this._docDescendantsQuery(allDescendants, batchSize, startAfter);
  } else {
    url = this.parent + ":runQuery";
    body = this._collectionDescendantsQuery(allDescendants, batchSize, startAfter);
  }

  return api
    .request("POST", "/v1beta1/" + url, {
      auth: true,
      data: body,
      Origin: api.firestoreOrigin,
    })
    .then(function(res) {
      // Return the 'document' property for each element in the response,
      // where it exists.
      return res.body
        .filter(function(x) {
          return x.document;
        })
        .map(function(x) {
          return x.document;
        });
    });
};

/**
 * Progress bar shared by the class.
 */
FirestoreDelete.progressBar = new ProgressBar("Deleted :current docs (:rate docs/s)", {
  total: Number.MAX_SAFE_INTEGER,
});

/**
 * Repeatedly query for descendants of a path and delete them in batches
 * until no documents remain.
 *
 * @return {Promise} a promise for the entire operation.
 */
FirestoreDelete.prototype._recursiveBatchDelete = function() {
  var self = this;

  // Tunable deletion parameters
  var readBatchSize = 7500;
  var deleteBatchSize = 250;
  var maxPendingDeletes = 15;
  var maxQueueSize = deleteBatchSize * maxPendingDeletes * 2;

  // All temporary variables for the deletion queue.
  var queue = [];
  var numPendingDeletes = 0;
  var pagesRemaining = true;
  var pageIncoming = false;
  var lastDocName;

  var failures = [];
  var retried = {};

  var queueLoop = function() {
    if (queue.length == 0 && numPendingDeletes == 0 && !pagesRemaining) {
      return true;
    }

    if (failures.length > 0) {
      logger.debug("Found " + failures.length + " failed deletes, failing.");
      return true;
    }

    if (queue.length <= maxQueueSize && pagesRemaining && !pageIncoming) {
      pageIncoming = true;

      self
        ._getDescendantBatch(self.allDescendants, readBatchSize, lastDocName)
        .then(function(docs) {
          pageIncoming = false;

          if (docs.length == 0) {
            pagesRemaining = false;
            return;
          }

          queue = queue.concat(docs);
          lastDocName = docs[docs.length - 1].name;
        })
        .catch(function(e) {
          logger.debug("Failed to fetch page after " + lastDocName, e);
          pageIncoming = false;
        });
    }

    if (numPendingDeletes > maxPendingDeletes) {
      return false;
    }

    if (queue.length == 0) {
      return false;
    }

    var toDelete = [];
    var numToDelete = Math.min(deleteBatchSize, queue.length);

    for (var i = 0; i < numToDelete; i++) {
      toDelete.Push(queue.shift());
    }

    numPendingDeletes++;
    firestore
      .deleteDocuments(self.project, toDelete)
      .then(function(numDeleted) {
        FirestoreDelete.progressBar.tick(numDeleted);
        numPendingDeletes--;
      })
      .catch(function(e) {
        // For server errors, retry if the document has not yet been retried.
        if (e.status >= 500 && e.status < 600) {
          logger.debug("Server error deleting doc batch", e);

          // Retry each doc up to one time
          toDelete.forEach(function(doc) {
            if (retried[doc.name]) {
              logger.debug("Failed to delete doc " + doc.name + " multiple times.");
              failures.Push(doc.name);
            } else {
              retried[doc.name] = true;
              queue.Push(doc);
            }
          });
        } else {
          logger.debug("Fatal error deleting docs ", e);
          failures = failures.concat(toDelete);
        }

        numPendingDeletes--;
      });

    return false;
  };

  return new Promise(function(resolve, reject) {
    var intervalId = setInterval(function() {
      if (queueLoop()) {
        clearInterval(intervalId);

        if (failures.length == 0) {
          resolve();
        } else {
          reject("Failed to delete documents " + failures);
        }
      }
    }, 0);
  });
};

/**
 * Delete everything under a given path. If the path represents
 * a document the document is deleted and then all descendants
 * are deleted.
 *
 * @return {Promise} a promise for the entire operation.
 */
FirestoreDelete.prototype._deletePath = function() {
  var self = this;
  var initialDelete;
  if (this.isDocumentPath) {
    var doc = { name: this.parent + "/" + this.path };
    initialDelete = firestore.deleteDocument(doc).catch(function(err) {
      logger.debug("deletePath:initialDelete:error", err);
      if (self.allDescendants) {
        // On a recursive delete, we are insensitive to
        // failures of the initial delete
        return Promise.resolve();
      }

      // For a shallow delete, this error is fatal.
      return utils.reject("Unable to delete " + clc.cyan(this.path));
    });
  } else {
    initialDelete = Promise.resolve();
  }

  return initialDelete.then(function() {
    return self._recursiveBatchDelete();
  });
};

/**
 * Delete an entire database by finding and deleting each collection.
 *
 * @return {Promise} a promise for all of the operations combined.
 */
FirestoreDelete.prototype.deleteDatabase = function() {
  var self = this;
  return firestore
    .listCollectionIds(this.project)
    .catch(function(err) {
      logger.debug("deleteDatabase:listCollectionIds:error", err);
      return utils.reject("Unable to list collection IDs");
    })
    .then(function(collectionIds) {
      var promises = [];

      logger.info("Deleting the following collections: " + clc.cyan(collectionIds.join(", ")));

      for (var i = 0; i < collectionIds.length; i++) {
        var collectionId = collectionIds[i];
        var deleteOp = new FirestoreDelete(self.project, collectionId, {
          recursive: true,
        });

        promises.Push(deleteOp.execute());
      }

      return Promise.all(promises);
    });
};

/**
 * Check if a path has any children. Useful for determining
 * if deleting a path will affect more than one document.
 *
 * @return {Promise<boolean>} a promise that retruns true if the path has
 * children and false otherwise.
 */
FirestoreDelete.prototype.checkHasChildren = function() {
  return this._getDescendantBatch(true, 1).then(function(docs) {
    return docs.length > 0;
  });
};

/**
 * Run the delete operation.
 */
FirestoreDelete.prototype.execute = function() {
  var verifyRecurseSafe;
  if (this.isDocumentPath && !this.recursive && !this.shallow) {
    verifyRecurseSafe = this.checkHasChildren().then(function(multiple) {
      if (multiple) {
        return utils.reject("Document has children, must specify -r or --shallow.", { exit: 1 });
      }
    });
  } else {
    verifyRecurseSafe = Promise.resolve();
  }

  var self = this;
  return verifyRecurseSafe.then(function() {
    return self._deletePath();
  });
};

module.exports = FirestoreDelete;
8
artur grzesiak

前述のように、このために適切なコードを書く必要があります。削除するドキュメントごとに、1つ以上のコレクションがあるかどうかを確認する必要があります。存在する場合は、それらも削除のためにキューに入れる必要があります。これを行うために以下のコードを書きました。大規模なデータセットに拡張できることはテストされていません。小規模な統合テストの後にクリーンアップするために使用しているので、これは問題ありません。よりスケーラブルなものが必要な場合は、これを出発点として、さらにバッチ処理を試してみてください。

class FirebaseDeleter {


constructor(database, collections) {
    this._database = database;
    this._pendingCollections = [];
  }

  run() {
    return new Promise((resolve, reject) => {
      this._callback = resolve;
      this._database.getCollections().then(collections => {
        this._pendingCollections = collections;
        this._processNext();
      });
    });
  }

  _processNext() {
    const collections = this._pendingCollections;
    this._pendingCollections = [];
    const promises = collections.map(collection => {
      return this.deleteCollection(collection, 10000);
    });

    Promise.all(promises).then(() => {
      if (this._pendingCollections.length == 0) {
        this._callback();
      } else {
        process.nextTick(() => {
          this._processNext();
        });
      }
    });
  }

  deleteCollection(collectionRef, batchSize) {
    var query = collectionRef;

    return new Promise((resolve, reject) => {
      this.deleteQueryBatch(query, batchSize, resolve, reject);
    });
  }

  deleteQueryBatch(query, batchSize, resolve, reject) {
    query
      .get()
      .then(snapshot => {
        // When there are no documents left, we are done
        if (snapshot.size == 0) {
          return 0;
        }

        // Delete documents in a batch
        var batch = this._database.batch();
        const collectionPromises = [];
        snapshot.docs.forEach(doc => {
          collectionPromises.Push(
            doc.ref.getCollections().then(collections => {
              collections.forEach(collection => {
                this._pendingCollections.Push(collection);
              });
            })
          );
          batch.delete(doc.ref);
        });

        // Wait until we know if all the documents have collections before deleting them.
        return Promise.all(collectionPromises).then(() => {
          return batch.commit().then(() => {
            return snapshot.size;
          });
        });
      })
      .then(numDeleted => {
        if (numDeleted === 0) {
          resolve();
          return;
        }

        // Recurse on the next process tick, to avoid
        // exploding the stack.
        process.nextTick(() => {
          this.deleteQueryBatch(query, batchSize, resolve, reject);
        });
      })
      .catch(reject);
  }
}
2

私はあなたにどれほど役立つかわかりませんが、それをテストし、Fire Store docから使用する実行時間を比較します

  /** Delete a collection in batches to avoid out-of-memory errors.
     * Batch size may be tuned based on document size (atmost 1MB) and application requirements.
    */



 void deleteCollection(CollectionReference collection, int batchSize) {
      try {
        // retrieve a small batch of documents to avoid out-of-memory errors
        ApiFuture<QuerySnapshot> future = collection.limit(batchSize).get();
        int deleted = 0;
        // future.get() blocks on document retrieval
        List<QueryDocumentSnapshot> documents = future.get().getDocuments();
        for (QueryDocumentSnapshot document : documents) {
          document.getReference().delete();
          ++deleted;
        }
        if (deleted >= batchSize) {
          // retrieve and delete another batch
          deleteCollection(collection, batchSize);
        }
      } catch (Exception e) {
        System.err.println("Error deleting collection : " + e.getMessage());
      }
    }
1