fatal error: concurrent map writes

[Multiply]

Version information

• terraform: v1.6.4
• terraform provider: v1.12.0

Describe the bug

Custom fields are cached (https://github.com/labd/terraform-provider-commercetools/blob/85d81c7642951a6a06e87c46fe6860b901819cf0/commercetools/custom_fields.go#L15C5-L15C15) when resolved, and are not using a mutex for writes, which can result in concurrent writes and panics.

I realize we're not using the latest versions of terraform and provider, but the bug is still present in the latest version.

Simply add a mutex and lock/unlock around map usage, and the problem should go away.

To Reproduce

Run multiple custom field type lookups at the same time, and hit the race condition.
I've run the provider for 2+ years without hitting this issue more than a couple of times, so it's a "rare" bug.

Expected behavior

The plugin shouldn't crash, when running multiple lookups at the same time.

Screenshots

I've provided the output below

Additional context

Do you want to perform these actions?
  Terraform will perform the actions described above.
  Only 'yes' will be accepted to approve.

  Enter a value: yes

module.commercetools_production.commercetools_store.X: Creating...
module.commercetools_production.commercetools_store.Y: Creating...
module.commercetools_production.commercetools_store.Z: Creating...
╷
│ Error: Plugin did not respond
│
│   with module.commercetools_production.commercetools_store.X,
│   on ../../modules/commercetools/stores.tf line 979, in resource "commercetools_store" "X":
│  979: resource "commercetools_store" "X" {
│
│ The plugin encountered an error, and failed to respond to the plugin.(*GRPCProvider).ApplyResourceChange call. The plugin logs may contain more details.
╵
╷
│ Error: Plugin did not respond
│
│   with module.commercetools_production.commercetools_store.Y,
│   on ../../modules/commercetools/stores.tf line 1009, in resource "commercetools_store" "Y":
│ 1009: resource "commercetools_store" "Y" {
│
│ The plugin encountered an error, and failed to respond to the plugin.(*GRPCProvider).ApplyResourceChange call. The plugin logs may contain more details.
╵
╷
│ Error: Plugin did not respond
│
│   with module.commercetools_production.commercetools_store.Z,
│   on ../../modules/commercetools/stores.tf line 1039, in resource "commercetools_store" "Z":
│ 1039: resource "commercetools_store" "Z" {
│
│ The plugin encountered an error, and failed to respond to the plugin.(*GRPCProvider).ApplyResourceChange call. The plugin logs may contain more details.
╵

Stack trace from the terraform-provider-commercetools_v1.12.0 plugin:

fatal error: concurrent map writes

goroutine 43 [running]:
github.com/labd/terraform-provider-commercetools/commercetools.getTypeResource({0x101ba9708, 0x14000807980}, 0x140001247f8, 0x140008086e0?)
        github.com/labd/terraform-provider-commercetools/commercetools/custom_fields.go:256 +0x2b0
github.com/labd/terraform-provider-commercetools/commercetools.CreateCustomFieldDraft({0x101ba9708, 0x14000807980}, 0x14000404a45?, 0x5?)
        github.com/labd/terraform-provider-commercetools/commercetools/custom_fields.go:43 +0x58
github.com/labd/terraform-provider-commercetools/commercetools.resourceStoreCreate({0x101ba9708?, 0x14000807980}, 0x140005d3900, {0x101b8c780?, 0x140001247f8})
        github.com/labd/terraform-provider-commercetools/commercetools/resource_store.go:102 +0x4ac
github.com/hashicorp/terraform-plugin-sdk/v2/helper/schema.(*Resource).create(0x14000323180, {0x101ba9740, 0x140006a1ad0}, 0xd?, {0x101b8c780, 0x140001247f8})
        github.com/hashicorp/terraform-plugin-sdk/[email protected]/helper/schema/resource.go:707 +0xe8
github.com/hashicorp/terraform-plugin-sdk/v2/helper/schema.(*Resource).Apply(0x14000323180, {0x101ba9740, 0x140006a1ad0}, 0x14000136820, 0x140005d3700, {0x101b8c780, 0x140001247f8})
        github.com/hashicorp/terraform-plugin-sdk/[email protected]/helper/schema/resource.go:837 +0x888
github.com/hashicorp/terraform-plugin-sdk/v2/helper/schema.(*GRPCProviderServer).ApplyResourceChange(0x1400034c600, {0x101ba9740?, 0x140006a19b0?}, 0x1400070c190)
        github.com/hashicorp/terraform-plugin-sdk/[email protected]/helper/schema/grpc_provider.go:1021 +0xb78
github.com/hashicorp/terraform-plugin-mux/tf5muxserver.muxServer.ApplyResourceChange({0x140003365a0, 0x14000336600, {0x140002fde80, 0x2, 0x2}, {0x0, 0x0, 0x0}, {0x0, 0x0, ...}, ...}, ...)
        github.com/hashicorp/[email protected]/tf5muxserver/mux_server_ApplyResourceChange.go:27 +0xdc
github.com/hashicorp/terraform-plugin-go/tfprotov5/tf5server.(*server).ApplyResourceChange(0x1400033ebe0, {0x101ba9740?, 0x140006a0e70?}, 0x140002e2700)
        github.com/hashicorp/[email protected]/tfprotov5/tf5server/server.go:821 +0x3bc
github.com/hashicorp/terraform-plugin-go/tfprotov5/internal/tfplugin5._Provider_ApplyResourceChange_Handler({0x101b35d20?, 0x1400033ebe0}, {0x101ba9740, 0x140006a0e70}, 0x140002e2690, 0x0)
        github.com/hashicorp/[email protected]/tfprotov5/internal/tfplugin5/tfplugin5_grpc.pb.go:422 +0x170
google.golang.org/grpc.(*Server).processUnaryRPC(0x140001c21e0, {0x101bae838, 0x140001024e0}, 0x1400034ad80, 0x140003fecc0, 0x10235d4e0, 0x0)
        google.golang.org/[email protected]/server.go:1337 +0xc90
google.golang.org/grpc.(*Server).handleStream(0x140001c21e0, {0x101bae838, 0x140001024e0}, 0x1400034ad80, 0x0)
        google.golang.org/[email protected]/server.go:1714 +0x82c
google.golang.org/grpc.(*Server).serveStreams.func1.1()
        google.golang.org/[email protected]/server.go:959 +0x84
created by google.golang.org/grpc.(*Server).serveStreams.func1
        google.golang.org/[email protected]/server.go:957 +0x16c

goroutine 1 [select]:
github.com/hashicorp/go-plugin.Serve(0x14000374060)
        github.com/hashicorp/[email protected]/server.go:474 +0x1120
github.com/hashicorp/terraform-plugin-go/tfprotov5/tf5server.Serve({0x10167a981, 0x28}, 0x140001c1a40, {0x0, 0x0, 0x0})
        github.com/hashicorp/[email protected]/tfprotov5/tf5server/server.go:315 +0xa50
main.main()
        github.com/labd/terraform-provider-commercetools/main.go:59 +0x380

goroutine 31 [select]:
github.com/hashicorp/go-plugin.(*gRPCBrokerServer).Recv(0x1400023e390?)
        github.com/hashicorp/[email protected]/grpc_broker.go:124 +0x58
github.com/hashicorp/go-plugin.(*GRPCBroker).Run(0x14000366e10)
        github.com/hashicorp/[email protected]/grpc_broker.go:414 +0x40
created by github.com/hashicorp/go-plugin.(*GRPCServer).Init
        github.com/hashicorp/[email protected]/grpc_server.go:88 +0x420

goroutine 32 [IO wait]:
internal/poll.runtime_pollWait(0x129c80a50, 0x72)
        runtime/netpoll.go:306 +0xa0
internal/poll.(*pollDesc).wait(0x140003744e0?, 0x1400048c000?, 0x1)
        internal/poll/fd_poll_runtime.go:84 +0x28
internal/poll.(*pollDesc).waitRead(...)
        internal/poll/fd_poll_runtime.go:89
internal/poll.(*FD).Read(0x140003744e0, {0x1400048c000, 0x1000, 0x1000})
        internal/poll/fd_unix.go:167 +0x200
os.(*File).read(...)
        os/file_posix.go:31
os.(*File).Read(0x1400000efa0, {0x1400048c000?, 0x400?, 0x1018b1da0?})
        os/file.go:118 +0x5c
bufio.(*Reader).Read(0x1400008ef30, {0x1400048e000, 0x400, 0x0?})
        bufio/bufio.go:237 +0x1e0
github.com/hashicorp/go-plugin.copyChan({0x101bb2b38, 0x1400033eaa0}, 0x0?, {0x101ba4a00?, 0x1400000efa0?})
        github.com/hashicorp/[email protected]/grpc_stdio.go:184 +0x164
created by github.com/hashicorp/go-plugin.newGRPCStdioServer
        github.com/hashicorp/[email protected]/grpc_stdio.go:40 +0x10c

goroutine 33 [IO wait]:
internal/poll.runtime_pollWait(0x129c80870, 0x72)
        runtime/netpoll.go:306 +0xa0
internal/poll.(*pollDesc).wait(0x140003745a0?, 0x1400010e000?, 0x1)
        internal/poll/fd_poll_runtime.go:84 +0x28
internal/poll.(*pollDesc).waitRead(...)
        internal/poll/fd_poll_runtime.go:89
internal/poll.(*FD).Read(0x140003745a0, {0x1400010e000, 0x1000, 0x1000})
        internal/poll/fd_unix.go:167 +0x200
os.(*File).read(...)
        os/file_posix.go:31
os.(*File).Read(0x1400000efb0, {0x1400010e000?, 0x400?, 0x1018b1da0?})
        os/file.go:118 +0x5c
bufio.(*Reader).Read(0x1400008f730, {0x14000110000, 0x400, 0x0?})
        bufio/bufio.go:237 +0x1e0
github.com/hashicorp/go-plugin.copyChan({0x101bb2b38, 0x1400033eaa0}, 0x0?, {0x101ba4a00?, 0x1400000efb0?})
        github.com/hashicorp/[email protected]/grpc_stdio.go:184 +0x164
created by github.com/hashicorp/go-plugin.newGRPCStdioServer
        github.com/hashicorp/[email protected]/grpc_stdio.go:41 +0x198

goroutine 35 [syscall]:
os/signal.signal_recv()
        runtime/sigqueue.go:149 +0x2c
os/signal.loop()
        os/signal/signal_unix.go:23 +0x1c
created by os/signal.Notify.func1.1
        os/signal/signal.go:151 +0x2c

goroutine 36 [chan receive]:
github.com/hashicorp/go-plugin.Serve.func3()
        github.com/hashicorp/[email protected]/server.go:439 +0x70
created by github.com/hashicorp/go-plugin.Serve
        github.com/hashicorp/[email protected]/server.go:436 +0xf18

goroutine 37 [IO wait]:

Error: The terraform-provider-commercetools_v1.12.0 plugin crashed!

This is always indicative of a bug within the plugin. It would be immensely
helpful if you could report the crash with the plugin's maintainers so that it
can be fixed. The output above should help diagnose the issue.