open-consul/command/agent/snapshot_endpoint.go
James Phillips bc29610124 Adds support for snapshots and restores. (#2396)
* Updates Raft library to get new snapshot/restore API.

* Basic backup and restore working, but need some cleanup.

* Breaks out a snapshot module and adds a SHA256 integrity check.

* Adds snapshot ACL and fills in some missing comments.

* Require a consistent read for snapshots.

* Make sure snapshot works if ACLs aren't enabled.

* Adds a bit of package documentation.

* Returns an empty response from restore to avoid EOF errors.

* Adds API client support for snapshots.

* Makes internal file names match on-disk file snapshots.

* Adds DC and token coverage for snapshot API test.

* Adds missing documentation.

* Adds a unit test for the snapshot client endpoint.

* Moves the connection pool out of the client for easier testing.

* Fixes an incidental issue in the prepared query unit test.

I realized I had two servers in bootstrap mode so this wasn't a good setup.

* Adds a half close to the TCP stream and fixes panic on error.

* Adds client and endpoint tests for snapshots.

* Moves the pool back into the snapshot RPC client.

* Adds a TLS test and fixes half-closes for TLS connections.

* Tweaks some comments.

* Adds a low-level snapshot test.

This is independent of Consul so we can pull this out into a library
later if we want to.

* Cleans up snapshot and archive and completes archive tests.

* Sends a clear error for snapshot operations in dev mode.

Snapshots require the Raft snapshots to be readable, which isn't supported
in dev mode. Send a clear error instead of a deep-down Raft one.

* Adds docs for the snapshot endpoint.

* Adds a stale mode and index feedback for snapshot saves.

This gives folks a way to extract data even if the cluster has no
leader.

* Changes the internal format of a snapshot from zip to tgz.

* Pulls in Raft fix to cancel inflight before a restore.

* Pulls in new Raft restore interface.

* Adds metadata to snapshot saves and a verify function.

* Adds basic save and restore snapshot CLI commands.

* Gets rid of tarball extensions and adds restore message.

* Fixes an incidental bad link in the KV docs.

* Adds documentation for the snapshot CLI commands.

* Scuttle any request body when a snapshot is saved.

* Fixes archive unit test error message check.

* Allows for nil output writers in snapshot RPC handlers.

* Renames hash list Decode to DecodeAndVerify.

* Closes the client connection for snapshot ops.

* Lowers timeout for restore ops.

* Updates Raft vendor to get new Restore signature and integrates with Consul.

* Bounces the leader's internal state when we do a restore.
2016-10-25 19:20:24 -07:00

51 lines
1.2 KiB
Go

package agent
import (
"bytes"
"net/http"
"github.com/hashicorp/consul/consul/structs"
)
// Snapshot handles requests to take and restore snapshots. This uses a special
// mechanism to make the RPC since we potentially stream large amounts of data
// as part of these requests.
func (s *HTTPServer) Snapshot(resp http.ResponseWriter, req *http.Request) (interface{}, error) {
var args structs.SnapshotRequest
s.parseDC(req, &args.Datacenter)
s.parseToken(req, &args.Token)
if _, ok := req.URL.Query()["stale"]; ok {
args.AllowStale = true
}
switch req.Method {
case "GET":
args.Op = structs.SnapshotSave
// Headers need to go out before we stream the body.
replyFn := func(reply *structs.SnapshotResponse) error {
setMeta(resp, &reply.QueryMeta)
return nil
}
// Don't bother sending any request body through since it will
// be ignored.
var null bytes.Buffer
if err := s.agent.SnapshotRPC(&args, &null, resp, replyFn); err != nil {
return nil, err
}
return nil, nil
case "PUT":
args.Op = structs.SnapshotRestore
if err := s.agent.SnapshotRPC(&args, req.Body, resp, nil); err != nil {
return nil, err
}
return nil, nil
default:
resp.WriteHeader(http.StatusMethodNotAllowed)
return nil, nil
}
}