fix(web): job log polls while active, one service history limit (#7)

internal/master/web/server.go

@@ -23,6 +23,9 @@ import (
 //go:embed templates/*.html static/*
 var assets embed.FS
 
+// serviceJobsLimit is how many jobs the service page lists.
+const serviceJobsLimit = 20
+
 var agentNamePattern = regexp.MustCompile(`^[a-z0-9][a-z0-9-]{0,62}$`)
 
 // Store is the storage the UI reads and writes. *store.Store satisfies it.
@@ -203,7 +206,7 @@ func (s *Server) serviceDetail(r *http.Request, id int64) (pageData, error) {
 	} else if err != nil {
 		return data, err
 	}
-	data.Jobs, err = s.store.ListJobs(r.Context(), model.JobFilter{ServiceID: id, Limit: 20})
+	data.Jobs, err = s.store.ListJobs(r.Context(), model.JobFilter{ServiceID: id, Limit: serviceJobsLimit})
 	return data, err
 }
 
@@ -225,7 +228,7 @@ func (s *Server) serviceJobsFragment(w http.ResponseWriter, r *http.Request) {
 	if !ok {
 		return
 	}
-	jobs, err := s.store.ListJobs(r.Context(), model.JobFilter{ServiceID: id, Limit: 20})
+	jobs, err := s.store.ListJobs(r.Context(), model.JobFilter{ServiceID: id, Limit: serviceJobsLimit})
 	if err != nil {
 		s.fail(w, err)
 		return

internal/master/web/server_test.go

@@ -482,6 +482,19 @@ func TestJobFragment_RereadsFromStore(t *testing.T) {
 	assert.Contains(t, body, "step 2")
 }
 
+func TestJobFragment_PollsOnlyWhileActive(t *testing.T) {
+	srv, store, _, _, _ := newTestEnv(t)
+	store.jobs = []model.Job{
+		{ID: 42, ServiceID: 1, Status: model.JobRunning, CreatedAt: time.Now()},
+		{ID: 43, ServiceID: 1, Status: model.JobSucceeded, CreatedAt: time.Now()},
+	}
+	_, body := get(t, srv, "/fragments/jobs/42")
+	assert.Contains(t, body, `hx-trigger="sse:job-42, every 2s"`)
+	_, body = get(t, srv, "/fragments/jobs/43")
+	assert.Contains(t, body, `hx-trigger="sse:job-43"`)
+	assert.NotContains(t, body, "every 2s")
+}
+
 func TestJob_NotFound(t *testing.T) {
 	srv, _, _, _ := newTestServer(t)
 	for _, path := range []string{"/jobs/99", "/fragments/jobs/99"} {

internal/master/web/templates/job.html

@@ -1,12 +1,12 @@
 {{define "content"}}
 <h1>Job #{{.Job.ID}}</h1>
 <p><a href="/services/{{.Job.ServiceID}}">{{.Job.ServiceName}}</a></p>
-<div id="job" hx-get="/fragments/jobs/{{.Job.ID}}" hx-trigger="sse:job-{{.Job.ID}}" hx-swap="innerHTML">
 {{template "job" .}}
-</div>
 {{end}}
 
+{{/* The wrapper is part of the fragment and swapped as outerHTML, so a finished job drops the polling timer. The timer recovers from a dropped SSE signal. */}}
 {{define "job"}}
+<div id="job" hx-get="/fragments/jobs/{{.Job.ID}}" hx-trigger="sse:job-{{.Job.ID}}{{if .Job.Active}}, every 2s{{end}}" hx-swap="outerHTML">
 <table class="details">
   <tr><th>Status</th><td class="status status-job-{{.Job.Status}}">{{.Job.Status}}</td></tr>
   <tr><th>From</th><td><code>{{shortRef .Job.FromRef}}</code></td></tr>
@@ -18,4 +18,5 @@
 {{if .Job.Error}}<p class="error">{{.Job.Error}}</p>{{end}}
 {{if .Job.OutputTruncated}}<p class="muted">Earlier output truncated.</p>{{end}}
 <pre class="log">{{.Job.Output}}</pre>
+</div>
 {{end}}