ArangoDB Manual

This is an introduction to ArangoDB's REST interface for documents.

REST Interface for Documents

Documents, Identifiers, Handles

Document: Documents in ArangoDB are JSON objects. These objects can be nested (to any depth) and may contains lists. Each document is unique identified by its document handle.

For example:

{
  "_id" : "1234567/2345678",
  "_rev" : "3456789",
  "firstName" : "Hugo",
  "lastName" : "Schlonz",
  "address" : {
    "street" : "Strasse 1",
    "city" : "Hier"
  },
  "hobbies" : [
    "swimming",
    "biking",
    "programming"
  ]
}

All documents contain two special fields, the document handle in _id and the etag aka document revision in _rev.

Document Handle: A document handle uniquely identifies a document in the database. It is a string and consists of a collection identifier and a document identifier separated by /.

Document Identifier: A document identifier identifies a document in a given collection. It is an integer and is unique within the collection of the document.

Document Revision: As AvocaodDB supports MVCC, documents can exist in more than one revision. The document revision is the MVCC token used to identify a particular revision of a document. It is an integer and unique within the list of document revision for a single document. Earlier revision of a document have smaller numbers. In order to find a particular revision of a document, you need the document handle and the document revision.

Document Etag: The document revision enclosed in double quotes.

The basic operations (create, read, update, delete) for documents are mapped to the standard HTTP methods (POST, GET, PUT, DELETE). An identifier for the document revision is returned in the "ETag" header field. If you modify a document, you can use the "If-Match" field to detect conflicts. The revision of a document can be checking using the HTTP method HEAD.

Address and ETag of an Document

All documents in ArangoDB have a document handle. This handle uniquely defines a document and is managed by ArangoDB. All documents are found under the URI:

http://server:port/_api/document/document-handle

For example: Assume that the document handle, which is stored in the _id field of the document, is 7254820/362549736, then the URL of that document is:

http://localhost:8529/_api/document/7254820/362549736

Each document also has a document revision or etag with is returned in the "ETag" header field when requesting a document.

If you obtain a document using GET and you want to check if a newer revision is available, then you can use the "If-None-Match" header. If the document is unchanged, a HTTP 412 is returned.

If you want to update or delete a document, then you can use the "If-Match" header. If the document has changed, then the operation is aborted and a HTTP 412 is returned.

Working with Documents using REST

GET /_api/document (reads a document)

GET /_api/document/document-handle

Returns the document identified by document-handle. The returned document contains two special attributes: _id containing the document handle and _rev containing the revision.

If the document exists, then a HTTP 200 is returned and the JSON representation of the document is the body of the response.

If the document-handle points to a non-existing document, then a HTTP 404 is returned and the body contains an error document.

If the "If-None-Match" header is given, then it must contain exactly one etag. The document is returned, if it has a different revision than the given etag. Otherwise a HTTP 304 is returned.

If the "If-Match" header is given, then it must contain exactly one etag. The document is returned, if it has the same revision ad the given etag. Otherwise a HTTP 412 is returned. As an alternative you can supply the etag in an attribute rev in the URL.

Examples

Use a document handle:

> curl -X GET --dump - http://localhost:8529/_api/document/73482/28411694

HTTP/1.1 200 OK
content-type: application/json; charset=utf-8
etag: "28411694"

{
  "_rev": 28411694,
  "_id": "73482/28411694",
  "Hallo": "World"
}

Use a document handle and an etag:

> curl -X GET '-H if-none-match: "28542766"' --dump - http://localhost:8529/_api/document/73482/28542766

HTTP/1.1 304 Not Modified
content-type: text/plain;charset=utf-8
etag: "28542766"

Unknown document handle:

> curl -X GET --dump - http://localhost:8529/_api/document/73482/234567

HTTP/1.1 404 Not Found
content-type: application/json; charset=utf-8

{
  "errorMessage": "document /_api/document/73482/234567 not found",
  "errorNum": 1202,
  "code": 404,
  "error": true
}

POST /_api/document (creates a document)

POST /_api/document?collection=collection-identifier

Creates a new document in the collection identified by the collection-identifier. A JSON representation of the document must be passed as the body of the POST request.

If the document was created successfully, then a HTTP 201 is returned and the "Location" header contains the path to the newly created document. The "ETag" header field contains the revision of the document.

The body of the response contains a JSON object with the same information. The attribute _id contains the document handle of the newly created document, the attribute _rev contains the document revision.

If the collection parameter waitForSync is false, then a HTTP 202 is returned in order to indicate that the document has been accepted but not yet stored.

If the collection-identifier is unknown, then a HTTP 404 is returned and the body of the response contains an error document.

If the body does not contain a valid JSON representation of an document, then a HTTP 400 is returned and the body of the response contains an error document.

POST /_api/document?collection=collection-name &createCollection=create-flag

Instead of a collection-identifier, a collection-name can be used. If create-flag has a value of true or yes, then the collection is created if it does not yet exist. Other values for create-flag will be ignored so the collection must be present for the operation to succeed.

Examples

Create a document given a collection identifier 161039 for the collection named demo. Note that the revision identifier might or might by equal to the last part of the document handle. It generally will be equal, but there is no guaranty.

> curl --data @- -X POST --dump - http://localhost:8529/_api/document?collection=73482
{ "Hallo" : "World" }

HTTP/1.1 201 Created
content-type: application/json; charset=utf-8
location: /_api/document/73482/26445614
etag: "26445614"

{
  "_rev": 26445614,
  "_id": "73482/26445614",
  "error": false
}

Create a document in a collection where waitForSync is false.

> curl --data @- -X POST --dump - http://localhost:8529/_api/document?collection=2957066
{ "Hallo" : "World" }

HTTP/1.1 202 Accepted
content-type: application/json; charset=utf-8
location: /_api/document/2957066/26576686
etag: "26576686"

{
  "_rev": 26576686,
  "_id": "2957066/26576686",
  "error": false
}

Create a document in a known, named collection

> curl --data @- -X POST --dump - http://localhost:8529/_api/document?collection=example
{ "Hallo" : "World" }

HTTP/1.1 201 Created
content-type: application/json; charset=utf-8
location: /_api/document/73482/26707758
etag: "26707758"

{
  "_rev": 26707758,
  "_id": "73482/26707758",
  "error": false
}

Create a document in a new, named collection

> curl --data @- -X POST --dump - http://localhost:8529/_api/document?collection=example&createCollection=true
{ "Hallo" : "World" }

HTTP/1.1 202 Accepted
content-type: application/json; charset=utf-8
location: /document/26838830/28280622
etag: "28280622"

{
  "_rev": 28280622,
  "_id": "26838830/28280622",
  "error": false
}

Unknown collection identifier:

> curl --data @- -X POST --dump - http://localhost:8529/_api/document?collection=123456
{}

HTTP/1.1 404 Not Found
content-type: application/json; charset=utf-8

{
  "errorMessage": "collection /_api/collection/123456 not found",
  "errorNum": 1203,
  "code": 404,
  "error": true
}

Illegal document:

> curl --data @- -X POST --dump - http://localhost:8529/_api/document?collection=73482
{ 1 : 2 }

HTTP/1.1 400 Bad Request
content-type: application/json; charset=utf-8

{
  "errorMessage": "expecting attribute name",
  "errorNum": 600,
  "code": 400,
  "error": true
}

PUT /_api/document (updates a document)

PUT /_api/document/document-handle

Completely updates (i.e. replaces) the document identified by document-handle. If the document exists and can be updated, then a HTTP 201 is returned and the "ETag" header field contains the new revision of the document.

If the new document passed in the body of the request contains the document-handle in the attribute _id and the revision in _rev, these attributes will be ignored. Only the URI and the "ETag" header are relevant in order to avoid confusion when using proxies.

The body of the response contains a JSON object with the information about the handle and the revision. The attribute _id contains the known document-handle of the updated document, the attribute _rev contains the new document revision.

If the document does not exist, then a HTTP 404 is returned and the body of the response contains an error document.

If an etag is supplied in the "If-Match" header field, then the ArangoDB checks that the revision of the document is equal to the etag. If there is a mismatch, then a HTTP 409 conflict is returned and no update is performed.

PUT /_api/document/document-handle?policy=policy

As before, if policy is error. If policy is last, then the last write will win.

PUT /_api/document/collection-identifier/document-identifier?rev=etag

You can also supply the etag using the parameter rev instead of an "ETag" header. You must never supply both the "ETag" header and the rev parameter.

Examples

Using document handle:

> curl --data @- -X PUT --dump - http://localhost:8529/_api/document/73482/29853486
{ "World" : "Hallo" }

HTTP/1.1 200 OK
content-type: application/json; charset=utf-8

{
  "_rev": 29919022,
  "_id": "73482/29853486",
  "error": false
}

Unknown document handle:

> curl --data @- -X PUT --dump - http://localhost:8529/_api/document/73482/234567
{}

HTTP/1.1 404 Not Found
content-type: application/json; charset=utf-8

{
  "errorMessage": "document /_api/document/73482/234567 not found",
  "errorNum": 1202,
  "code": 404,
  "error": true
}

Produce a revision conflict:

> curl --data @- -X PUT '-H if-match: "30050093"' --dump - http://_api/localhost:8529/document/73482/30050094
{ "World" : "Hallo" }

HTTP/1.1 412 Precondition Failed
content-type: application/json; charset=utf-8

{
  "_rev": 30050094,
  "_id": "73482/30050094",
  "error": true
}

Last write wins:

> curl --data @- -X PUT '-H if-match: "30246701"' --dump - http://localhost:8529/_api/document/73482/30246702?policy=last
{ "World" : "Hallo" }

HTTP/1.1 200 OK
content-type: application/json; charset=utf-8

{
  "_rev": 30312238,
  "_id": "73482/30246702",
  "error": false
}

Alternative to header field:

> curl --data @- -X PUT --dump - http://localhost:8529/_api/document/73482/30443310?rev=30443309
{ "World" : "Hallo" }

HTTP/1.1 412 Precondition Failed
content-type: application/json; charset=utf-8

{
  "_rev": 30443310,
  "_id": "73482/30443310",
  "error": true
}

PATCH /_api/document (patches a document)

PATCH /_api/document/document-handle

Partially updates the document identified by document-handle. The body of the request must contain a JSON document with the attributes to patch (the patch document). All attributes from the patch document will be added to the existing document if they do not yet exist, and overwritten in the existing document if they do exist there.

Setting an attribute value to null in the patch document will cause a value of null be saved for the attribute by default. If the intention is to delete existing attributes with the patch command, the URL parameter keepNull can be used with a value of false. This will modify the behavior of the patch command to remove any attributes from the existing document that are contained in the patch document with an attribute value of null.

If the document does not exist, then a HTTP 404 is returned and the body of the response contains an error document.

Examples

> curl --data @- -X PATCH --dump - http://localhost:8529/_api/document/73482/7229681
{ "hello": "world" }

HTTP/1.1 200 OK
content-type: application/json; charset=utf-8

{
  "_rev": 11916057,
  "_id": "73482/7229681",
  "error": false
}

> curl --data @- -X PATCH --dump - http://localhost:8529/_api/document/73482/7229681
{ "numbers": { "one": 1, "two": 2, "three": 3, "empty": null } }

HTTP/1.1 200 OK
content-type: application/json; charset=utf-8

{
  "_rev": 12309273,
  "_id": "73482/7229681",
  "error": false
}

> curl -X GET --dump - http://localhost:8529/_api/document/73482/7229681
{ "numbers": { "one": 1, "two": 2, "three": 3, "empty": null } }

HTTP/1.1 200 OK
content-type: application/json; charset=utf-8

{
  "hello": "world",
  "numbers": {
    "empty": null,
    "one": 1,
    "two": 2,
    "three": 3
  },
  "_rev": 12309273,
  "_id": "73482/7229681"
}

> curl --data @- -X PATCH --dump - http://localhost:8529/_api/document/73482/7229681?keepNull=false
{ "hello": null, "numbers": { "four": 4 } }

{
  "_rev": 12571417,
  "_id": "73482/7229681",
  "error": false
}

> curl -X GET --dump - http://localhost:8529/_api/document/73482/7229681

HTTP/1.1 200 OK
content-type: application/json; charset=utf-8

{
  "numbers": {
    "empty": null,
    "one": 1,
    "two": 2,
    "three": 3,
    "four": 4,
  },
  "_rev": 12571417,
  "_id": "73482/7229681"
}

DELETE /_api/document (deletes a document)

DELETE /_api/document/document-handle

Deletes the document identified by document-handle. If the document exists and could be deleted, then a HTTP 204 is returned.

If the document does not exist, then a HTTP 404 is returned and the body of the response contains an error document.

If an etag is supplied in the "If-Match" field, then the ArangoDB checks that the revision of the document is equal to the etag. If there is a mismatch, then a HTTP 412 conflict is returned and no delete is performed.

DELETE /_api/document/document-handle?policy=policy

As before, if policy is error. If policy is last, then the last write will win.

DELETE /_api/document/document-handle?rev=etag

You can also supply the etag using the parameter rev instead of an "If-Match" header. You must never supply both the "If-Match" header and the rev parameter.

Examples

Using document handle:

> curl -X DELETE --dump - http://localhost:8529/_api/document/73482/30967598

HTTP/1.1 200 OK
content-type: application/json; charset=utf-8

{
  "_rev": 30967598,
  "_id": "73482/30967598",
  "error": false
}

Unknown document handle:

> curl -X DELETE --dump - http://localhost:8529/_api/document/73482/234567

HTTP/1.1 404 Not Found
content-type: application/json; charset=utf-8

{
  "errorMessage": "document /_api/document/73482/234567 not found",
  "errorNum": 1202,
  "code": 404,
  "error": true
}

Revision conflict:

> curl -X DELETE '-H if-match: "31098669"' --dump - http://localhost:8529/_api/document/73482/31098670

HTTP/1.1 412 Precondition Failed
content-type: application/json; charset=utf-8

{
  "_rev": 31098670,
  "_id": "73482/31098670",
  "error": true
}

HEAD /_api/document (reads a document header)

HEAD /_api/document/document-handle

Like GET, but only returns the header fields and not the body. You can use this call to get the current revision of a document or check if the document was deleted.

Examples

> curl -X HEAD --dump - http://localhost:8529/_api/document/73482/29591342

HTTP/1.1 200 OK
content-type: application/json; charset=utf-8
etag: "29591342"

GET /_api/document (reads all document)

GET /_api/document?collection=collection-identifier

Returns a list of all URI for all documents from the collection identified by collection-identifier.

Instead of a collection-identifier, a collection name can be given.

Examples

> curl -X GET --dump - http://localhost:8529/_api/document?collection=6627082

HTTP/1.1 200 OK
content-type: application/json; charset=utf-8

{
  "documents": [
    "/document/6627082/29198126",
    "/document/6627082/29329198",
    "/document/6627082/29263662"
  ]
}

REST Interface for Documents

Documents, Identifiers, Handles

Address and ETag of an Document

Working with Documents using REST