pool size must be > 0 error

Reproduce the failure with the shown fly deploy command and start at internal/command/deploy/plan.go:388, where acquireLeases panics with a zero pool size. Trace the callers in machines_deploymachinesapp.go and deploy.go to determine why deployment reaches that state. Done means the deployment no longer panics with this error and reports or handles the condition appropriately.

[1/2] Waiting for job
[2/2] Waiting for job

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pool size must be > 0
goroutine 1 [running]:
runtime/debug.Stack()
runtime/debug/stack.go:26 +0x64
github.com/superfly/flyctl/internal/sentry.printError({0x10678e180, 0x106c46750})
github.com/superfly/flyctl/internal/sentry/sentry.go:190 +0x168
github.com/superfly/flyctl/internal/sentry.Recover({0x10678e180, 0x106c46750})
github.com/superfly/flyctl/internal/sentry/sentry.go:180 +0xb8
main.run.func1()
github.com/superfly/flyctl/main.go:40 +0x34
panic({0x10678e180?, 0x106c46750?})
runtime/panic.go:792 +0x124
go.opentelemetry.io/otel/sdk/trace.(*recordingSpan).End.deferwrap1()
go.opentelemetry.io/otel/sdk@v1.34.0/trace/span.go:467 +0x2c
go.opentelemetry.io/otel/sdk/trace.(*recordingSpan).End(0x1400042c3c0, {0x0, 0x0, 0x14000c33818?})
go.opentelemetry.io/otel/sdk@v1.34.0/trace/span.go:506 +0xa04
panic({0x10678e180?, 0x106c46750?})
runtime/panic.go:792 +0x124
go.opentelemetry.io/otel/sdk/trace.(*recordingSpan).End.deferwrap1()
go.opentelemetry.io/otel/sdk@v1.34.0/trace/span.go:467 +0x2c
go.opentelemetry.io/otel/sdk/trace.(*recordingSpan).End(0x140009aa1e0, {0x0, 0x0, 0x14000c33300?})
go.opentelemetry.io/otel/sdk@v1.34.0/trace/span.go:506 +0xa04
panic({0x10678e180?, 0x106c46750?})
runtime/panic.go:792 +0x124
go.opentelemetry.io/otel/sdk/trace.(*recordingSpan).End.deferwrap1()
go.opentelemetry.io/otel/sdk@v1.34.0/trace/span.go:467 +0x2c
go.opentelemetry.io/otel/sdk/trace.(*recordingSpan).End(0x1400042c5a0, {0x0, 0x0, 0x140000021c0?})
go.opentelemetry.io/otel/sdk@v1.34.0/trace/span.go:506 +0xa04
panic({0x10678e180?, 0x106c46750?})
runtime/panic.go:792 +0x124
go.opentelemetry.io/otel/sdk/trace.(*recordingSpan).End.deferwrap1()
go.opentelemetry.io/otel/sdk@v1.34.0/trace/span.go:467 +0x2c
go.opentelemetry.io/otel/sdk/trace.(*recordingSpan).End(0x140009aa000, {0x0, 0x0, 0x14000c32680?})
go.opentelemetry.io/otel/sdk@v1.34.0/trace/span.go:506 +0xa04
panic({0x10678e180?, 0x106c46750?})
runtime/panic.go:792 +0x124
go.opentelemetry.io/otel/sdk/trace.(*recordingSpan).End.deferwrap1()
go.opentelemetry.io/otel/sdk@v1.34.0/trace/span.go:467 +0x2c
go.opentelemetry.io/otel/sdk/trace.(*recordingSpan).End(0x140007fc5a0, {0x0, 0x0, 0x14000c32378?})
go.opentelemetry.io/otel/sdk@v1.34.0/trace/span.go:506 +0xa04
panic({0x10678e180?, 0x106c46750?})
runtime/panic.go:792 +0x124
github.com/superfly/flyctl/internal/command/deploy.(*machineDeployment).acquireLeases(0x140009d1040, {0x106c74838, 0x14000e39680}, {0x140009fd340, 0x2, 0x14000ce9aa9?}, 0x0, 0x14000e396e0)
github.com/superfly/flyctl/internal/command/deploy/plan.go:388 +0x254
github.com/superfly/flyctl/internal/command/deploy.(*machineDeployment).updateMachinesWRecovery(0x140009d1040, {0x106c73e98, 0x14000a9ec00}, 0x14000e39620, 0x14000c32608, {0x0, 0x0}, {0xa0?, 0xef?, 0x65?, ...})
github.com/superfly/flyctl/internal/command/deploy/plan.go:190 +0x1020
github.com/superfly/flyctl/internal/command/deploy.(*machineDeployment).updateExistingMachinesWRecovery(0x140009d1040, {0x106c73e98, 0x14000a9ebd0}, {0x14000be5210, 0x2, 0x2})
github.com/superfly/flyctl/internal/command/deploy/machines_deploymachinesapp.go:684 +0x7c4
github.com/superfly/flyctl/internal/command/deploy.(*machineDeployment).updateExistingMachines(0x140009d1040, {0x106c73e98, 0x14000be3290}, {0x14000be5210, 0x2, 0x2})
github.com/superfly/flyctl/internal/command/deploy/machines_deploymachinesapp.go:557 +0x678
github.com/superfly/flyctl/internal/command/deploy.(*machineDeployment).deployMachinesApp(0x140009d1040, {0x106c73e98, 0x14000a035f0})
github.com/superfly/flyctl/internal/command/deploy/machines_deploymachinesapp.go:467 +0x520
github.com/superfly/flyctl/internal/command/deploy.(*machineDeployment).DeployMachinesApp(0x140009d1040, {0x106c73e98, 0x14000783e30})
github.com/superfly/flyctl/internal/command/deploy/machines_deploymachinesapp.go:87 +0x340
github.com/superfly/flyctl/internal/command/deploy.deployToMachines({0x106c73e98, 0x14000893950}, 0x140006ae680, 0x140007c03f8, 0x14000a325a0)
github.com/superfly/flyctl/internal/command/deploy/deploy.go:626 +0xf08
github.com/superfly/flyctl/internal/command/deploy.DeployWithConfig({0x106c73e98, 0x1400074d650}, 0x140006ae680, 0x0, 0x80?)
github.com/superfly/flyctl/internal/command/deploy/deploy.go:376 +0x588
github.com/superfly/flyctl/internal/command/deploy.(*Command).run(0x1080c4ce0?, {0x106c73e98, 0x140007482a0})
github.com/superfly/flyctl/internal/command/deploy/deploy.go:317 +0xc50
github.com/superfly/flyctl/internal/command/deploy.New.New.newRunE.func2(0x140006a9b08, {0x14000646640?, 0x4?, 0x1060d650e?})
github.com/superfly/flyctl/internal/command/command.go:142 +0x180
github.com/spf13/cobra.(*Command).execute(0x140006a9b08, {0x14000646620, 0x2, 0x2})
github.com/spf13/cobra@v1.8.1/command.go:985 +0x830
github.com/spf13/cobra.(*Command).ExecuteC(0x140005a8008)
github.com/spf13/cobra@v1.8.1/command.go:1117 +0x344
github.com/spf13/cobra.(*Command).ExecuteContextC(...)
github.com/spf13/cobra@v1.8.1/command.go:1050
github.com/superfly/flyctl/internal/cli.Run({0x106c74020?, 0x140004ec540?}, 0x14000596000, {0x1400014e090, 0x3, 0x3})
github.com/superfly/flyctl/internal/cli/cli.go:94 +0x5a8
main.run()
github.com/superfly/flyctl/main.go:47 +0x170
main.main()
github.com/superfly/flyctl/main.go:26 +0x20

➜ fly-log-shipper git:(main) ✗ fly deploy -c fly.axiom.prod.toml
==> Verifying app config
Validating fly.axiom.prod.toml
✓ Configuration is valid
--> Verified app config
==> Building image
Searching for image 'flyio/log-shipper:latest' remotely...
image found: img_0lq747158wxd46x3

Watch your deployment at https://fly.io/apps/fly-log-shipper-axiom-prod-quoowa3u/monitoring

Updating existing machines in 'fly-log-shipper-axiom-prod-quoowa3u' with rolling strategy

Oops, something went wrong! Could you try that again?

pool size must be > 0
goroutine 1 [running]:
runtime/debug.Stack()
runtime/debug/stack.go:26 +0x64
github.com/superfly/flyctl/internal/sentry.printError({0x104bf2180, 0x1050aa750})
github.com/superfly/flyctl/internal/sentry/sentry.go:190 +0x168
github.com/superfly/flyctl/internal/sentry.Recover({0x104bf2180, 0x1050aa750})
github.com/superfly/flyctl/internal/sentry/sentry.go:180 +0xb8
main.run.func1()
github.com/superfly/flyctl/main.go:40 +0x34
panic({0x104bf2180?, 0x1050aa750?})
runtime/panic.go:792 +0x124
go.opentelemetry.io/otel/sdk/trace.(*recordingSpan).End.deferwrap1()
go.opentelemetry.io/otel/sdk@v1.34.0/trace/span.go:467 +0x2c
go.opentelemetry.io/otel/sdk/trace.(*recordingSpan).End(0x140003ce3c0, {0x0, 0x0, 0x14000be5818?})
go.opentelemetry.io/otel/sdk@v1.34.0/trace/span.go:506 +0xa04
panic({0x104bf2180?, 0x1050aa750?})
runtime/panic.go:792 +0x124
go.opentelemetry.io/otel/sdk/trace.(*recordingSpan).End.deferwrap1()
go.opentelemetry.io/otel/sdk@v1.34.0/trace/span.go:467 +0x2c
go.opentelemetry.io/otel/sdk/trace.(*recordingSpan).End(0x140003cf0e0, {0x0, 0x0, 0x14000be5300?})
go.opentelemetry.io/otel/sdk@v1.34.0/trace/span.go:506 +0xa04
panic({0x104bf2180?, 0x1050aa750?})
runtime/panic.go:792 +0x124
go.opentelemetry.io/otel/sdk/trace.(*recordingSpan).End.deferwrap1()
go.opentelemetry.io/otel/sdk@v1.34.0/trace/span.go:467 +0x2c
go.opentelemetry.io/otel/sdk/trace.(*recordingSpan).End(0x140009b0780, {0x0, 0x0, 0x140000021c0?})
go.opentelemetry.io/otel/sdk@v1.34.0/trace/span.go:506 +0xa04
panic({0x104bf2180?, 0x1050aa750?})
runtime/panic.go:792 +0x124
go.opentelemetry.io/otel/sdk/trace.(*recordingSpan).End.deferwrap1()
go.opentelemetry.io/otel/sdk@v1.34.0/trace/span.go:467 +0x2c
go.opentelemetry.io/otel/sdk/trace.(*recordingSpan).End(0x140003ce5a0, {0x0, 0x0, 0x14000be4680?})
go.opentelemetry.io/otel/sdk@v1.34.0/trace/span.go:506 +0xa04
panic({0x104bf2180?, 0x1050aa750?})
runtime/panic.go:792 +0x124
go.opentelemetry.io/otel/sdk/trace.(*recordingSpan).End.deferwrap1()
go.opentelemetry.io/otel/sdk@v1.34.0/trace/span.go:467 +0x2c
go.opentelemetry.io/otel/sdk/trace.(*recordingSpan).End(0x140009b0f00, {0x0, 0x0, 0x14000be4378?})
go.opentelemetry.io/otel/sdk@v1.34.0/trace/span.go:506 +0xa04
panic({0x104bf2180?, 0x1050aa750?})
runtime/panic.go:792 +0x124
github.com/superfly/flyctl/internal/command/deploy.(*machineDeployment).acquireLeases(0x14000a8a9c0, {0x1050d8838, 0x14000976270}, {0x14000968d20, 0x1, 0x1400096c8a6?}, 0x0, 0x140009762d0)
github.com/superfly/flyctl/internal/command/deploy/plan.go:388 +0x254
github.com/superfly/flyctl/internal/command/deploy.(*machineDeployment).updateMachinesWRecovery(0x14000a8a9c0, {0x1050d7e98, 0x140007a4a20}, 0x14000976210, 0x14000be4608, {0x0, 0x0}, {0xa0?, 0x2f?, 0xac?, ...})
github.com/superfly/flyctl/internal/command/deploy/plan.go:190 +0x1020
github.com/superfly/flyctl/internal/command/deploy.(*machineDeployment).updateExistingMachinesWRecovery(0x14000a8a9c0, {0x1050d7e98, 0x140007a49f0}, {0x140006ce158, 0x1, 0x1})
github.com/superfly/flyctl/internal/command/deploy/machines_deploymachinesapp.go:684 +0x7c4
github.com/superfly/flyctl/internal/command/deploy.(*machineDeployment).updateExistingMachines(0x14000a8a9c0, {0x1050d7e98, 0x140005f13e0}, {0x140006ce158, 0x1, 0x1})
github.com/superfly/flyctl/internal/command/deploy/machines_deploymachinesapp.go:557 +0x678
github.com/superfly/flyctl/internal/command/deploy.(*machineDeployment).deployMachinesApp(0x14000a8a9c0, {0x1050d7e98, 0x140008942d0})
github.com/superfly/flyctl/internal/command/deploy/machines_deploymachinesapp.go:467 +0x520
github.com/superfly/flyctl/internal/command/deploy.(*machineDeployment).DeployMachinesApp(0x14000a8a9c0, {0x1050d7e98, 0x14000a981b0})
github.com/superfly/flyctl/internal/command/deploy/machines_deploymachinesapp.go:87 +0x340
github.com/superfly/flyctl/internal/command/deploy.deployToMachines({0x1050d7e98, 0x140008cf4a0}, 0x140004584e0, 0x140005f23f8, 0x1400079b4a0)
github.com/superfly/flyctl/internal/command/deploy/deploy.go:626 +0xf08
github.com/superfly/flyctl/internal/command/deploy.DeployWithConfig({0x1050d7e98, 0x14000733440}, 0x140004584e0, 0x0, 0x80?)
github.com/superfly/flyctl/internal/command/deploy/deploy.go:376 +0x588
github.com/superfly/flyctl/internal/command/deploy.(*Command).run(0x106528ce0?, {0x1050d7e98, 0x1400072e090})
github.com/superfly/flyctl/internal/command/deploy/deploy.go:317 +0xc50
github.com/superfly/flyctl/internal/command/deploy.New.New.newRunE.func2(0x140005bfb08, {0x140004b20a0?, 0x4?, 0x10453a50e?})
github.com/superfly/flyctl/internal/command/command.go:142 +0x180
github.com/spf13/cobra.(*Command).execute(0x140005bfb08, {0x140004b2040, 0x2, 0x2})
github.com/spf13/cobra@v1.8.1/command.go:985 +0x830
github.com/spf13/cobra.(*Command).ExecuteC(0x140006dc008)
github.com/spf13/cobra@v1.8.1/command.go:1117 +0x344
github.com/spf13/cobra.(*Command).ExecuteContextC(...)
github.com/spf13/cobra@v1.8.1/command.go:1050
github.com/superfly/flyctl/internal/cli.Run({0x1050d8020?, 0x140003fab40?}, 0x140006c0000, {0x1400004c0d0, 0x3, 0x3})
github.com/superfly/flyctl/internal/cli/cli.go:94 +0x5a8
main.run()
github.com/superfly/flyctl/main.go:47 +0x170
main.main()
github.com/superfly/flyctl/main.go:26 +0x20