docHistory

Retrieves complete histories for one or more documents

Definition

The docHistory command returns all versions of specified documents.

The docHistory command has the following form:

JavaScript

{
  "docHistory":
    {
      "collection": <string>,
      "filter":<document>,
      "projection":<document>
    }
 }

The command accepts the following fields:

Field	Type	Mandatory	Description
docHistory.collection	string	yes	The target collection
docHistory.filter	document	yes	A MongoDB compatible filter condition
docHistory.projection	document	no	A MongoDB compatible projection document

Output

The returned document contains a subset of the following fields:

Field	Type	Description
ok	number	The status of the command.
docHistory	array	An array of DocHistory Item's.

DocHistory Item

Field	Type	Description
collection	string	The collection which contains the document.
_id	any	The document id.
history	document	The document's history.
history.versions	array	An array of DocHistory Version's.

DocHistory Version

Field	Type	Description
minVersion	number	The version the document started.
maxVersion	number	The version the document ended.
status	string	The proof status of the document.
started	timestamp	The timestamp when the version started.
ended	timestamp	The timestamp when the version ended.
document	document	The document content.

Example

This example returns all versions of the document that contains the string 'Last Will and Testament' in the name attribute and returns just the name and uploadedAt attributes for each document.

JavaScript

> db.runCommand({docHistory:{
...    collection:'files_5c6b4735769348aee6f8fd00' ,
...    filter:{name:{$regex:"Last Will and Testament"}},
...    projection:{name:1,uploadedAt:1}
... }})
{
	"ok" : 1,
	"docHistory" : [
		{
			"collection" : "files_5c6b4735769348aee6f8fd00",
			"_id" : ObjectId("5c7f46eebe1e3eaea78b1abe"),
			"history" : {
				"versions" : [
					{
						"minVersion" : NumberLong(2),
						"maxVersion" : NumberLong(5),
						"status" : "Valid",
						"started" : "2019-03-06 03:05:02",
						"ended" : "2019-03-06 03:05:03",
						"document" : {
							"name" : "Last Will and Testament of John ProvenDocs.pdf",
							"uploadedAt" : "2019-03-06T04:05:02.765Z"
						}
					},
					{
						"minVersion" : NumberLong(6),
						"maxVersion" : NumberLong("9223372036854775807"),
						"status" : "Valid",
						"started" : "2019-03-06 03:13:27",
						"ended" : "2019-03-06 03:13:27",
						"document" : {
							"name" : "Last Will and Testement of John ProvenDocs.pdf",
							"uploadedAt" : "2019-03-06T04:13:27.562Z"
						}
					}
				]
			}
		}
	]
}

📘

Note:

docHistory will return an error if the amount of data returned exceeds the maximum network message size of approximately 64MB. If you encounter this error, you should use either the filter or projection clauses to reduce the amount of data returned.

You can use a projection to reduce the amount of document data returned. For instance, here we suppress all document data using a projection on a non-existent attribute:

JavaScript

db.runCommand({
  docHistory: { collection: collectionName, filter: { X 4 },
                      projection:{nonExistentAttribute:1} }}

If you really need to extract all versions of large documents you can do so using normal queries. If a filter condition is specified on provendb metadata attributes, then these will over-ride the implicit 'current version' filter. So for instance, this query will return all versions of the documents which has an _id of 4, and will return the metadata as well as the user data:

JavaScript

collection.find({'_provendb_metadata':{$exists:true},'_id':4},
                          {'_provendb_metadata':1});