PUT /api/groups/{gid}/members/{pid}
Add a principal to a group. Idempotent.
Adds {pid} to group {gid} and verifies by a fresh membership read -- a SEPARATE
operation, because the receipt the add resolves merely ECHOES the ids that were sent.
The request is idempotent: the path names the exact membership, so re-sending it leaves the same membership.
Authentication
Send the session id as Authorization: Bearer <session id>, and an RFC 9449 DPoP proof in the DPoP header if your session is bound to a key. The two are required together, not as alternatives — see Authenticating and Proving you hold your key.
There is no session cookie on any response and none is read on any request. Do not set credentials: "include" on a browser fetch.
Parameters
| Name | In | Required | Type | Description |
|---|---|---|---|---|
gid | path | yes | string | A group's principal id as 16 hex digits (the id field, not principalId). |
pid | path | yes | string | The member principal's id as 16 hex digits (the id field, not principalId). |
Request
No request body.
Responses
200
The principal is a member, verified by a fresh read.
| Field | Type | Required | Description |
|---|---|---|---|
code | string | no | Absent on success; NOT_SAVED when the read-back disagrees. |
gid | string | no | |
pid | string | no | |
saved | boolean | no | |
count | integer | no | |
members | array of Principal | no | The membership as a FRESH read shows it -- a separate operation from the write. |
detail | string | no |
Example
{
"code": "...",
"gid": "...",
"pid": "...",
"saved": true,
"count": 0,
"members": [
{
"id": "...",
"principalId": "...",
"systemId": 0,
"className": "...",
"name": "...",
"disabled": true,
"roleIds": [
"..."
],
"groupIds": [
"..."
]
}
],
"detail": "..."
}
400
BAD_REQUEST -- gid or pid is not 16 hex digits.
401
No live session, a DPoP proof that did not verify, or a certificate session whose certificate the key server now refuses.
SESSION_NOT_FOUND -- the credential names no session this Gateway holds.
SESSION_EXPIRED -- it aged out. Both carry reauth: true; obtain a new credential
rather than retrying.
PROOF_* -- the sender constraint refused. See the DPoP section of this document for the
full table; PROOF_MALFORMED is a 400 and PROOF_REPLAY_CACHE_FULL a 503, and the
rest are here.
SCOPED_CREDENTIAL_EXPIRED -- a scoped browser credential passed its fixed lifetime. Use
does not extend it: an idle timeout would be refreshed by exactly the traffic a stolen
handle produces.
CERTIFICATE_REVOKED -- on a session established by certificate login, the key server
re-checks the certificate that session was established with on its operations, and it
is now named by revocation evidence (ADR 0115). detail is the key server's sentence.
Every later operation of the session is refused the same way; log in with a different
certificate.
403
Authenticated, and refused. The codes differ in what they say about where the refusal
came from: ACCESS_DENIED, PRINCIPAL_DISABLED and DELEGATOR_REFUSED are the key
server's -- the last one on a DELEGATED session whose delegator has since been disabled,
lost its DELEGATION flag, been unenrolled or had its certificate revoked (ADR-0123); its
detail is the key server's sentence naming the delegator, and no new login helps until
an administrator restores it. REVOCATION_STATUS_UNAVAILABLE and
REVOCATION_EVIDENCE_STALE are the key server's too, on a session established by
certificate login: the same re-check found no current revocation evidence for that
certificate's issuer under a policy that requires it (ADR 0115) -- the credential is not
what was refused, and an operator importing a current CRL for the issuer is what helps --
while
NOT_WRITABLE, BUILT_IN_PRINCIPAL, OWN_ACCOUNT and
OBJECT_NOT_IN_CREDENTIAL_SCOPE are decided by the Gateway before anything is sent.
404
NO_GROUP, NOT_A_GROUP, or NO_PRINCIPAL -- no principal {pid}. Nothing was written.
409
CYCLIC_MEMBERSHIP -- the key server refused because this edge would close a loop in
group membership. Nothing was written. It is almost always the reverse
membership: the group is already reachable as a member of the principal you are
adding. This route does not walk the membership graph and cannot tell you which edge
closed the loop.
NOT_SAVED -- the key server did not refuse and the membership read-back does not
contain the principal.
500
A fault rather than a refusal.
OP_FAILED is the catch-all: the key server refused in words that match no classified
pattern, so the Gateway cannot say more than that the operation did not happen. Some key
server refusals that are conceptually a caller error arrive here rather than as a 4xx,
because the wire carries no distinguishing code -- where a route can recognise one from
its message it maps it, and each such mapping is documented on the operation.
503
A capacity ceiling or a missing deployment prerequisite. retryable says which.
A scope of session or process names the ceiling that was hit, and the response
carries Retry-After.
BUILD_NOT_ADMITTED (scope: process, retryable: true, Retry-After): the key server
does not admit this Gateway's client build. Every key-server connection the Gateway opens
attests the signed release it runs (TE_RELEASE_MANIFEST) right after it authenticates;
while that attestation is refused -- the release is not registered at the key server's
code-signing level, the level was raised under it, or the installed files no longer
match the signed manifest -- every route but GET /api/health and GET /api/ready
answers this, and detail names the cause. It is never a 401 or a 403: no credential
or role of the caller's is at fault. The Gateway re-attempts on a timer and recovers
without a restart once the key server admits it; GET /api/ready says when.
Error handling
Every failure answers JSON carrying at least code and detail. Match on code — detail is written for a human debugging the call and its wording is not part of the contract. See the error model.
| Status | Meaning |
|---|---|
400 | BAD_REQUEST -- gid or pid is not 16 hex digits. |
401 | No live session, a DPoP proof that did not verify, or a certificate session whose certificate the key server now refuses. SESSION_NOT_FOUND -- the credential names no session this Gateway holds. SESSION_EXPIRED -- it aged out. Both carry reauth: true; obtain a new credential rather than retrying. PROOF_* -- the sender constraint refused. See the DPoP section of this document for the full table; PROOF_MALFORMED is a 400 and PROOF_REPLAY_CACHE_FULL a 503, and the rest are here. SCOPED_CREDENTIAL_EXPIRED -- a scoped browser credential passed its fixed lifetime. Use does not extend it: an idle timeout would be refreshed by exactly the traffic a stolen handle produces. CERTIFICATE_REVOKED -- on a session established by certificate login, the key server re-checks the certificate that session was established with on its operations, and it is now named by revocation evidence (ADR 0115). detail is the key server's sentence. Every later operation of the session is refused the same way; log in with a different certificate. |
403 | Authenticated, and refused. The codes differ in what they say about where the refusal came from: ACCESS_DENIED, PRINCIPAL_DISABLED and DELEGATOR_REFUSED are the key server's -- the last one on a DELEGATED session whose delegator has since been disabled, lost its DELEGATION flag, been unenrolled or had its certificate revoked (ADR-0123); its detail is the key server's sentence naming the delegator, and no new login helps until an administrator restores it. REVOCATION_STATUS_UNAVAILABLE and REVOCATION_EVIDENCE_STALE are the key server's too, on a session established by certificate login: the same re-check found no current revocation evidence for that certificate's issuer under a policy that requires it (ADR 0115) -- the credential is not what was refused, and an operator importing a current CRL for the issuer is what helps -- while NOT_WRITABLE, BUILT_IN_PRINCIPAL, OWN_ACCOUNT and OBJECT_NOT_IN_CREDENTIAL_SCOPE are decided by the Gateway before anything is sent. |
404 | NO_GROUP, NOT_A_GROUP, or NO_PRINCIPAL -- no principal {pid}. Nothing was written. |
409 | CYCLIC_MEMBERSHIP -- the key server refused because this edge would close a loop in group membership. Nothing was written. It is almost always the reverse membership: the group is already reachable as a member of the principal you are adding. This route does not walk the membership graph and cannot tell you which edge closed the loop. NOT_SAVED -- the key server did not refuse and the membership read-back does not contain the principal. |
500 | A fault rather than a refusal. OP_FAILED is the catch-all: the key server refused in words that match no classified pattern, so the Gateway cannot say more than that the operation did not happen. Some key server refusals that are conceptually a caller error arrive here rather than as a 4xx, because the wire carries no distinguishing code -- where a route can recognise one from its message it maps it, and each such mapping is documented on the operation. |
503 | A capacity ceiling or a missing deployment prerequisite. retryable says which. A scope of session or process names the ceiling that was hit, and the response carries Retry-After. BUILD_NOT_ADMITTED (scope: process, retryable: true, Retry-After): the key server does not admit this Gateway's client build. Every key-server connection the Gateway opens attests the signed release it runs (TE_RELEASE_MANIFEST) right after it authenticates; while that attestation is refused -- the release is not registered at the key server's code-signing level, the level was raised under it, or the installed files no longer match the signed manifest -- every route but GET /api/health and GET /api/ready answers this, and detail names the cause. It is never a 401 or a 403: no credential or role of the caller's is at fault. The Gateway re-attempts on a timer and recovers without a restart once the key server admits it; GET /api/ready says when. |