From 98d4eac1c5b5d5b9618c28d6ea2b8e121935735b Mon Sep 17 00:00:00 2001
From: Zack Mullaly <zmullaly@mozilla.com>
Date: Mon, 19 Nov 2018 15:54:41 -0500
Subject: [PATCH] Only insert a new agent when we find out about one. Otherwise
 update agents in place when we deal with a heartbeat

---
 mig-api/agents/persist_heartbeat_postgres.go | 83 +++++---------------
 1 file changed, 18 insertions(+), 65 deletions(-)

diff --git a/mig-api/agents/persist_heartbeat_postgres.go b/mig-api/agents/persist_heartbeat_postgres.go
index ff135e3a..7c51231c 100644
--- a/mig-api/agents/persist_heartbeat_postgres.go
+++ b/mig-api/agents/persist_heartbeat_postgres.go
@@ -9,6 +9,7 @@ package agents
 import (
 	"fmt"
 
+	"github.com/mozilla/mig"
 	migdb "github.com/mozilla/mig/database"
 )
 
@@ -23,74 +24,26 @@ func NewPersistHeartbeatPostgres(db *migdb.DB) PersistHeartbeatPostgres {
 }
 
 func (persist PersistHeartbeatPostgres) PersistHeartbeat(heartbeat Heartbeat) error {
-	fmt.Printf("POST /heartbeat got heartbeat %v\n", heartbeat)
+	agent, err := persist.db.AgentByQueueAndPID(
+		heartbeat.QueueLoc,
+		int(heartbeat.PID))
 
-	agent := heartbeat.ToMigAgent()
-	//err := persist.db.InsertAgent(agent, nil)
-	agent, err := persist.db.AgentByQueueAndPID(agent.QueueLoc, agent.PID)
+	// If the agent doesn't exist, we want to record it as a new row.
+	// This is basically the case where an agent reports itself as operating
+	// for the first time.
 	if err != nil {
-		return err
+		agent.DestructionTime = time.Date(9998, time.January, 11, 11, 11, 11, 11, time.UTC)
+		agent.Status = mig.AgtStatusOnline
+		agent.StartTime = time.Now()
+		return persist.db.InsertAgent(agent, nil)
+	}
+
+	agent.Status = mig.AgtStatusOnline
+
+	cutoff := agent.RefreshTS.Add(15 * time.Second)
+	if !agent.RefreshTS.IsZero() && agent.RefreshTS.After(cutoff) {
+		return persist.db.ReplaceRefreshedAgent(agent)
 	}
 
 	return persist.db.UpdateAgentHeartbeat(agent)
 }
-
-// _dontrun invokes a goroutine that updates the agent table when a heartbeat
-// message would have been handled by the scheduler. For now we're holding onto
-// the code as a reference
-func _dontrun() {
-	go func() {
-		// if an agent already exists in database, we update it, otherwise we insert it
-		agent, err := ctx.DB.AgentByQueueAndPID(agt.QueueLoc, agt.PID)
-		if err != nil {
-			agt.DestructionTime = time.Date(9998, time.January, 11, 11, 11, 11, 11, time.UTC)
-			agt.Status = mig.AgtStatusOnline
-			// create a new agent, set starttime to now
-			agt.StartTime = time.Now()
-			err = ctx.DB.InsertAgent(agt, nil)
-			if err != nil {
-				ctx.Channels.Log <- mig.Log{Desc: fmt.Sprintf("Heartbeat DB insertion failed with error '%v' for agent '%s'", err, agt.Name)}.Err()
-			}
-		} else {
-			// the agent exists in database. reuse the existing ID, and keep the status if it was
-			// previously set to destroyed, otherwise set status to online
-			agt.ID = agent.ID
-			if agt.Status == mig.AgtStatusDestroyed {
-				agt.Status = agent.Status
-			} else {
-				agt.Status = mig.AgtStatusOnline
-			}
-			// If the refresh time is newer than what we know for the agent, replace
-			// the agent in the database with the newer information. We want to keep
-			// history here, so don't want to just update the information in the
-			// existing row.
-			//
-			// Note: with older agents which might not send a refresh time, the refresh
-			// time will be interpreted as the zero value, and the agents should just
-			// update using UpdateAgentHeartbeat()
-			if agt.RefreshTS.IsZero() {
-				ctx.Channels.Log <- mig.Log{Desc: fmt.Sprintf("agent '%v' not sending refresh time, perhaps an older version?", agt.Name)}.Warning()
-			}
-			cutoff := agent.RefreshTS.Add(15 * time.Second)
-			if !agt.RefreshTS.IsZero() && agt.RefreshTS.After(cutoff) {
-				ctx.Channels.Log <- mig.Log{Desc: fmt.Sprintf("replacing refreshed agent for agent '%v'", agt.Name)}.Info()
-				err = ctx.DB.ReplaceRefreshedAgent(agt)
-				if err != nil {
-					ctx.Channels.Log <- mig.Log{Desc: fmt.Sprintf("Heartbeat DB update failed (refresh) with error '%v' for agent '%s'", err, agt.Name)}.Err()
-				}
-			} else {
-				err = ctx.DB.UpdateAgentHeartbeat(agt)
-				if err != nil {
-					ctx.Channels.Log <- mig.Log{Desc: fmt.Sprintf("Heartbeat DB update failed with error '%v' for agent '%s'", err, agt.Name)}.Err()
-				}
-			}
-			// if the agent that exists in the database has a status of 'destroyed'
-			// we should not be received a heartbeat from it. so, if detectmultiagents
-			// is set in the scheduler configuration, we pass the agent queue over to the
-			// routine than handles the destruction of agents
-			if agent.Status == mig.AgtStatusDestroyed && ctx.Agent.DetectMultiAgents {
-				ctx.Channels.DetectDupAgents <- agent.QueueLoc
-			}
-		}
-	}()
-}