When endpoint definition in brief format missing a : it causes panic

[hellt]

User report:

if we define two bridges and put the same interface name into each clab panics.

Smth like

- endpoints: ["node1:e1-48", "br-1:eth1"]
- endpoints: ["node1:e1-49", "br-2:eth1"]

INFO[0000] Containerlab v0.47.2 started
panic: runtime error: index out of range [1] with length 1 [recovered]
        panic: runtime error: index out of range [1] with length 1

goroutine 1 [running]:
gopkg.in/yaml%2ev2.handleErr(0xc000fbf560)
        gopkg.in/yaml.v2@v2.4.0/yaml.go:249 +0x6d
panic({0x2d20500, 0xc00062b398})
        runtime/panic.go:884 +0x213
github.com/srl-labs/containerlab/links.extractHostNodeInterfaceData(0xc000628510, 0x10?)
        github.com/srl-labs/containerlab/links/link.go:320 +0x12b
github.com/srl-labs/containerlab/links.linkVEthRawFromLinkBriefRaw(0xc000628510)
        github.com/srl-labs/containerlab/links/link_veth.go:74 +0x25
github.com/srl-labs/containerlab/links.(*LinkBriefRaw).ToTypeSpecificRawLink(0xc000628510)
        github.com/srl-labs/containerlab/links/link_brief.go:41 +0x1d6
github.com/srl-labs/containerlab/links.(*LinkDefinition).UnmarshalYAML(0xc000f3d140, 0xc000f3d160)
        github.com/srl-labs/containerlab/links/link.go:214 +0x2f6
gopkg.in/yaml%2ev2.(*decoder).callUnmarshaler(0xc000c88180, 0xc000829500, {0x7fc3329fd598, 0xc000f3d140})
        gopkg.in/yaml.v2@v2.4.0/decode.go:270 +0xa4

[hellt]

might be of interest to you @steiler

[steiler]

Try with a different interface on the node side in this example they are both the same... But yes also thus error should be caught

[hellt]

@steiler the node interfaces were different (copy paste issue)
it is the same interface on the bridges side are not handled proprely.

[steiler]

Here is my config:

# topology documentation: http://containerlab.dev/lab-examples/single-srl/
name: test91

topology:
  nodes:
    l1:
      kind: linux
      image: alpine:latest
      cmd: "sleep 5d"
    br-1:
      kind: bridge
    br-2:
      kind: bridge
  links:
    - endpoints: ["l1:eth1", "br-1:eth1"]
    - endpoints: ["l1:eth2", "br-2:eth1"]

And this is what I get:

EBU[0000] Checking if docker network "clab" exists     
DEBU[0000] network "clab" was found. Reusing it...      
DEBU[0000] Docker network "clab", bridge name "br-110b4d465e7a" 
DEBU[0000] Disable RPF check on the docker host         
DEBU[0000] Enable LLDP on the linux bridge br-110b4d465e7a 
DEBU[0000] Disabling TX checksum offloading for the br-110b4d465e7a bridge interface... 
DEBU[0000] found iptables forwarding rule targeting the bridge "br-110b4d465e7a". Skipping creation of the forwarding rule. 
Error: root network namespace endpoint "eth1" defined by multiple nodes [br-1, br-2]

So to me, this looks fine. Please provide more input.

[steiler]

Also where it crashed according to your output is the following function

func extractHostNodeInterfaceData(lb *LinkBriefRaw, specialEPIndex int) (host, hostIf, node, nodeIf string) {
	// the index of the node is the specialEndpointIndex +1  modulo 2
	nodeindex := (specialEPIndex + 1) % 2

	hostData := strings.SplitN(lb.Endpoints[specialEPIndex], ":", 2)
	nodeData := strings.SplitN(lb.Endpoints[nodeindex], ":", 2)

	host = hostData[0]
	hostIf = hostData[1]
	node = nodeData[0]
	nodeIf = nodeData[1]

	return host, hostIf, node, nodeIf
}

right at nodeIf = nodeData[1] ...
so that is still parsing the data you've provided... to me it looks like there was no colon between nodename and interface or so... such that the split did only yield a slice of length 1...

[hellt]

yep, you're spot on
I trimmed down the topo, since it was huge, and indeed one of the endpoints has been set as
br-ens-clab-eth3. I will change the description accordingly