@@ -200,12 +200,12 @@ func Agent(ctx context.Context, writer io.Writer, agentID uuid.UUID, opts AgentO
200200
201201switch agent .LifecycleState {
202202case codersdk .WorkspaceAgentLifecycleReady :
203- sw .Complete (stage ,agent .ReadyAt . Sub ( * agent .StartedAt ))
203+ sw .Complete (stage ,safeDuration ( sw , agent .ReadyAt , agent .StartedAt ))
204204case codersdk .WorkspaceAgentLifecycleStartTimeout :
205205sw .Fail (stage ,0 )
206206sw .Log (time.Time {},codersdk .LogLevelWarn ,"Warning: A startup script timed out and your workspace may be incomplete." )
207207case codersdk .WorkspaceAgentLifecycleStartError :
208- sw .Fail (stage ,agent .ReadyAt . Sub ( * agent .StartedAt ))
208+ sw .Fail (stage ,safeDuration ( sw , agent .ReadyAt , agent .StartedAt ))
209209// Use zero time (omitted) to separate these from the startup logs.
210210sw .Log (time.Time {},codersdk .LogLevelWarn ,"Warning: A startup script exited with an error and your workspace may be incomplete." )
211211sw .Log (time.Time {},codersdk .LogLevelWarn ,troubleshootingMessage (agent ,"https://coder.com/docs/v2/latest/templates#startup-script-exited-with-an-error" ))
@@ -221,7 +221,7 @@ func Agent(ctx context.Context, writer io.Writer, agentID uuid.UUID, opts AgentO
221221case agent .LifecycleState .ShuttingDown ():
222222// We no longer know if the startup script failed or not,
223223// but we need to tell the user something.
224- sw .Complete (stage ,agent .ReadyAt . Sub ( * agent .StartedAt ))
224+ sw .Complete (stage ,safeDuration ( sw , agent .ReadyAt , agent .StartedAt ))
225225return errAgentShuttingDown
226226}
227227}
@@ -238,13 +238,13 @@ func Agent(ctx context.Context, writer io.Writer, agentID uuid.UUID, opts AgentO
238238sw .Log (time .Now (),codersdk .LogLevelWarn ,"Wait for it to reconnect or restart your workspace." )
239239sw .Log (time .Now (),codersdk .LogLevelWarn ,troubleshootingMessage (agent ,"https://coder.com/docs/v2/latest/templates#agent-connection-issues" ))
240240
241- disconnectedAt := * agent .DisconnectedAt
241+ disconnectedAt := agent .DisconnectedAt
242242for agent .Status == codersdk .WorkspaceAgentDisconnected {
243243if agent ,err = fetch ();err != nil {
244244return xerrors .Errorf ("fetch: %w" ,err )
245245}
246246}
247- sw .Complete (stage ,agent .LastConnectedAt . Sub ( disconnectedAt ))
247+ sw .Complete (stage ,safeDuration ( sw , agent .LastConnectedAt , disconnectedAt ))
248248}
249249}
250250}
@@ -257,6 +257,25 @@ func troubleshootingMessage(agent codersdk.WorkspaceAgent, url string) string {
257257return m
258258}
259259
260+ // safeDuration returns a-b. If a or b is nil, it returns 0.
261+ // This is because we often dereference a time pointer, which can
262+ // cause a panic. These dereferences are used to calculate durations,
263+ // which are not critical, and therefor should not break things
264+ // when it fails.
265+ // A panic has been observed in a test.
266+ func safeDuration (sw * stageWriter ,a ,b * time.Time ) time.Duration {
267+ if a == nil || b == nil {
268+ if sw != nil {
269+ // Ideally the message includes which fields are <nil>, but you can
270+ // use the surrounding log lines to figure that out. And passing more
271+ // params makes this unwieldy.
272+ sw .Log (time .Now (),codersdk .LogLevelWarn ,"Warning: Failed to calculate duration from a time being <nil>." )
273+ }
274+ return 0
275+ }
276+ return a .Sub (* b )
277+ }
278+
260279type closeFunc func ()error
261280
262281func (c closeFunc )Close ()error {