Delegates

A document may delegate access on its behalf to other documents by adding the other documents' References to its delegates list. Any tokens belonging to a member of delegates are granted access as though they were tokens belonging to the delegating document.

Example

For example, if a user (with document ID 1) has read access to the "spells" collection, but another user (with document ID 2) does not, the first user may grant access via delegation to the second user with the following query:

try
{
    Value result = await client.Query(
        Update(
            Ref(Collection("users"), 1),
            Obj("delegates", Arr(Ref(Collection("users"), 2)))
        )
    );
    Console.WriteLine(result);
}
catch (Exception e)
{
    Console.WriteLine($"ERROR: {e.Message}");
}
ObjectV(ref: RefV(id = "1", collection = RefV(id = "users", collection = RefV(id = "collections"))),ts: LongV(1621374013780000),data: ObjectV(name: StringV(Alice Crypto),email: StringV(alice@site.example.com)),delegates: Arr(RefV(id = "2", collection = RefV(id = "users", collection = RefV(id = "collections")))))
result, err := client.Query(
	f.Update(
		f.Ref(f.Collection("users"), "1"),
		f.Obj{"delegates": f.Arr{f.Ref(f.Collection("users"), "2")}},
	))

if err != nil {
	fmt.Fprintln(os.Stderr, err)
} else {
	fmt.Println(result)
map[data:map[email:alice@site.example.com name:Alice Crypto] delegates:[{2 0xc000109d40 0xc000109d40 <nil>}] ref:{1 0xc000109b60 0xc000109b60 <nil>} ts:1621374015010000]
System.out.println(
    client.query(
        Update(
            Ref(Collection(Value("users")), Value(1)),
            Obj("delegates", Arr(Ref(Collection(Value("users")), Value(2))))
        )
    ).get());
{ref: ref(id = "1", collection = ref(id = "users", collection = ref(id = "collections"))), ts: 1621374020240000, data: {name: "Alice Crypto", email: "alice@site.example.com"}, delegates: [ref(id = "2", collection = ref(id = "users", collection = ref(id = "collections")))]}
client.query(
  q.Update(
    q.Ref(q.Collection('users'), 1),
    { delegates: [q.Ref(q.Collection('users'), 2)] },
  )
)
.then((ret) => console.log(ret))
.catch((err) => console.error(
  'Error: [%s] %s: %s',
  err.name,
  err.message,
  err.errors()[0].description,
))
{
  ref: Ref(Collection("users"), "1"),
  ts: 1621374020750000,
  data: { name: 'Alice Crypto', email: 'alice@site.example.com' },
  delegates: [ Ref(Collection("users"), "2") ]
}
result = client.query(
  q.update(
    q.ref(q.collection("users"), 1),
    {"delegates": [q.ref(q.collection("users"), 2)]}
  )
)
print(result)
{'ref': Ref(id=1, collection=Ref(id=users, collection=Ref(id=collections))), 'ts': 1621374021070000, 'data': {'name': 'Alice Crypto', 'email': 'alice@site.example.com'}, 'delegates': [Ref(id=2, collection=Ref(id=users, collection=Ref(id=collections)))]}
Update(
  Ref(Collection('users'), 1),
  { delegates: [Ref(Collection('users'), 2)] },
)
{
  ref: Ref(Collection("users"), "1"),
  ts: 1624310593770000,
  data: { name: 'Alice Crypto', email: 'alice@site.example.com' },
  delegates: [ Ref(Collection("users"), "2") ]
}
Query metrics:

  •    bytesIn: 122

  •   bytesOut: 320

  • computeOps:   1

  •    readOps:   0

  •   writeOps:   1

  •  readBytes: 186

  • writeBytes: 142

  •  queryTime: 8ms

  •    retries:   0

Now, when the second user attempts to read from the "spells" collection, they are granted the same level of access as the first user.

Delegates are not transitive — in the example above, the second user may not delegate the first user’s permissions to another user.

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