From 71d807f607589f2eb4fea4e83e3876d122c8afc0 Mon Sep 17 00:00:00 2001 From: James Phillips Date: Tue, 31 Jan 2017 08:43:16 -0800 Subject: [PATCH] Adds gopsutil into node ID process and attempts to use host ID, if availabile. --- command/agent/agent.go | 50 +++++++++++++++++++++++++++++++++++++----- 1 file changed, 44 insertions(+), 6 deletions(-) diff --git a/command/agent/agent.go b/command/agent/agent.go index 6f31717827..11395c59e5 100644 --- a/command/agent/agent.go +++ b/command/agent/agent.go @@ -27,6 +27,7 @@ import ( "github.com/hashicorp/go-uuid" "github.com/hashicorp/serf/coordinate" "github.com/hashicorp/serf/serf" + "github.com/shirou/gopsutil/host" ) const ( @@ -593,7 +594,46 @@ func (a *Agent) setupClient() error { return nil } -// setupNodeID will pull the persisted node ID, if any, or create a random one +// makeNodeID will try to find a host-specific ID, or else will generate a +// random ID. The returned ID will always be formatted as a GUID. We don't +// tell the caller whether this ID is random or stable since the consequences +// are high for us if this changes, so we will persist it either way. This will +// let gopsutil change implementations without affecting in-place upgrades of +// nodes. +func (a *Agent) makeNodeID() (string, error) { + var id string + + // Try to get a stable ID associated with the host itself. + info, err := host.Info() + if err != nil { + a.logger.Printf("[DEBUG] Failed to get a unique id from the host, generating a random one: %v", err) + goto RANDOM_ID + } + + // Make sure the host ID parses as a UUID, since we don't have complete + // control over this process. + id = strings.ToLower(info.HostID) + if _, err := uuid.ParseUUID(id); err != nil { + a.logger.Printf("[DEBUG] Host ID %q isn't formatted as a UUID, generating a random one: %v", + id, err) + goto RANDOM_ID + } + + a.logger.Printf("[DEBUG] Using ID %q from host as node ID", id) + return id, nil + + // Worst case, just generate a random UUID. +RANDOM_ID: + id, err = uuid.GenerateUUID() + if err != nil { + return "", err + } + + a.logger.Printf("[DEBUG] Using random UUID %q as node ID", id) + return id, nil +} + +// setupNodeID will pull the persisted node ID, if any, or create one // and persist it. func (a *Agent) setupNodeID(config *Config) error { // If they've configured a node ID manually then just use that, as @@ -606,15 +646,14 @@ func (a *Agent) setupNodeID(config *Config) error { return nil } - // For dev mode we have no filesystem access so just make a GUID. + // For dev mode we have no filesystem access so just make one. if a.config.DevMode { - id, err := uuid.GenerateUUID() + id, err := a.makeNodeID() if err != nil { return err } config.NodeID = types.NodeID(id) - a.logger.Printf("[INFO] agent: Generated unique node ID %q for this agent (will not be persisted in dev mode)", config.NodeID) return nil } @@ -637,7 +676,7 @@ func (a *Agent) setupNodeID(config *Config) error { // If we still don't have a valid node ID, make one. if config.NodeID == "" { - id, err := uuid.GenerateUUID() + id, err := a.makeNodeID() if err != nil { return err } @@ -649,7 +688,6 @@ func (a *Agent) setupNodeID(config *Config) error { } config.NodeID = types.NodeID(id) - a.logger.Printf("[INFO] agent: Generated unique node ID %q for this agent (persisted)", config.NodeID) } return nil }