c8volt

c8volt - Yet Another Camunda 8 CLI Tool?

No, c8volt is different. Its design and development focus on operational effectiveness, ensuring that done is done. There are plenty of operational tasks where you want to be sure that:

• A process was canceled – is it really in the cancelled state?
• A process tree was deleted – are all instances truly gone?
• A process instance was started – has it already reached the expected user task?
• A process variable was set – does it hold the correct value?

c8volt focuses on real operational use cases while still providing the familiar CLI functionality such as standard CRUD commands on various resources.

Quick Start with c8volt

1. Install Camunda 8.8 Run
   Download Camunda 8 Run, unpack and start it with ./start.sh. Use listed relevant URLs and default credentials to create the configuration for c8volt.

   $ ./start.sh
   
   System Version Information
   --------------------------
   Camunda Details:
     Version: 8.8.2
   --------------------------
   [...]
   -------------------------------------------
   Access each component at the following urls with these default credentials:
   - username: demo
   - password: demo
   
   Operate:                    http://localhost:8080/operate
   Tasklist:                   http://localhost:8080/tasklist
   Identity:                   http://localhost:8080/identity
   
   Orchestration Cluster API:  http://localhost:8080/v2/
   [...]
   

2. Install c8volt
   Download the latest release relevant to your OS from the c8volt Releases page and unpack it. Here is an example for macOS ARM64:

   $ wget -q --show-progress -c -O c8volt.tar.gz https://github.com/grafvonb/c8volt/releases/download/v0.1.61/c8volt_0.1.61_Darwin_arm64.tar.gz
   $ tar -xvf c8volt.tar.gz
   

3. Configure c8volt
   Create a configuration file (YAML) in the folder where you unpacked c8volt with the name config.yaml or in $HOME/.c8volt/config.yaml with the minimal connection and authentication details:

   apis:
     version: "8.8"
     camunda_api:
       base_url: "http://localhost:8080/v2"
   
   auth:
     mode: "cookie"
     cookie:
       base_url: "http://localhost:8080"
   

4. Run c8volt
   Test the connection and list cluster topology:

   ./c8volt get cluster-topology
   

   or use explicit path to config file:

   ./c8volt get cluster-topology --config ./config-minimal.yaml
   

   You should see output like this:

   {
     "Brokers": [
       {
         "Host": "192.168.178.88",
         "NodeId": 0,
         "Partitions": [
           {
             "Health": "healthy",
             "PartitionId": 1,
             "Role": "leader"
           }
         ],
         "Port": 26501,
         "Version": "8.8.0"
       }
     ],
     "ClusterSize": 1,
     "GatewayVersion": "8.8.0",
     "PartitionsCount": 1,
     "ReplicationFactor": 1,
     "LastCompletedChangeId": ""
   }  
   

Highlights

c8volt simplifies various tasks related to Camunda 8, including these special use cases:

• Delete active process instances by cancelling them first

  ./c8volt delete pi --key <process-instance-key> --cancel
  

• List process instances that are children (sub-processes) of other process instances

  ./c8volt get pi --bpmn-process-id=<bpmn-process-id> --children-only
  

• List process instances that are parents of other process instances

  ./c8volt get pi --bpmn-process-id=<bpmn-process-id> --parents-only
  

• List process instances that are children of orphan parent process instances
  (i.e., their parent process instance no longer exists)

  ./c8volt get pi --bpmn-process-id=<bpmn-process-id> --orphan-parents-only
  

• List process instances for a specific process definition (model) and its first version

  ./c8volt get pi --bpmn-process-id=<bpmn-process-id> --process-version=1
  

• List process instances with incidents

  ./c8volt get pi --incidents-only
  

• List process instances without incidents

  ./c8volt get pi --no-incidents-only
  

• Recursive search (walk) process instances with parent–child relationships

  • List all child process instances of a given process instance

    ./c8volt walk pi --mode children --start-key <process-instance-key>
    

  • List path from a given process instance to its root ancestor (top-level parent)

    ./c8volt walk pi --mode parent --start-key <process-instance-key>
    

  • List the entire family (parent, grandparent, …) of a given process instance (traverse up and down the tree)

    ./c8volt walk pi --mode family --start-key <process-instance-key>
    

• List process instances in one line per instance (suitable for scripting)
  Works with all get commands.

  ./c8volt get pi --one-line
  

• List process instances just by their keys (suitable for scripting)
  Works with all get commands.

  ./c8volt get pi --keys-only
  

• …and more to come:

• bulk operations (e.g., delete multiple process instances by filter)

• multiple Camunda 8 API versions support (currently 8.7, 8.8, 8.9 planned)

• or submit a proposal or contribute code on GitHub

Supported Camunda 8 APIs

• 8.7.x
• 8.8.x

Configuration

Choose authentication method

c8volt supports two authentication methods for connecting to Camunda 8 APIs:

• OAuth2 (OIDC)
• API Cookie (development with Camunda 8 Run only)

Authentication with OAuth2 (OIDC)

c8volt supports OAuth2 (OIDC) authentication with client credentials flow. You need to provide the following settings:

• Token URL
• Client ID
• Client Secret
• Scopes (optional, depending on your identity provider and API setup)

Here is an example configuration snippet for OAuth2 authentication for Camunda 8 running locally with Keycloak:

Authentication with API Cookie (development with Camunda 8 Run only)

This method is only suitable for local development with Camunda 8 Run, as it uses the API cookie set by the web interface. You need to provide the following settings:

• API base URL
• (optional) Username and Password (if not set, defaults to demo/demo)

Here is an example configuration snippet for API Cookie authentication for Camunda 8 Run running locally:

Connecting to Camunda's 8 APIs

To run c8volt, you need to configure the connection to your Camunda 8 APIs (Camunda, Operate, Tasklist) and authentication details. With the introduction of Camunda v8.8 and unified APIs, some of these settings may become optional or redundant in the future.

c8volt expects the following API configurations:

• Camunda 8 API (required, formally known as Zeebe API), since v8.8 known as Orchestration Cluster API
• Operate API (optional, required for some commands, if not set defaults to Camunda 8 API), since v8.8 deprecated in favor of unified Orchestration Cluster API
• Tasklist API (optional, required for some commands, if not set defaults to Camunda 8 API), since v8.8 deprecated in favor of unified Orchestration Cluster API

If you use Camunda 8 Run with API Cookie Authentication (Development only)

After starting Camunda 8 Run, you can find the API endpoint in the terminal output (default is http://localhost:8080/v2). (current, October 2025, gotcha: if you use --port flag, the terminal output still shows port 8080, but it actually runs on the port you specified).

Provide the following settings in the config file, environment variables, or flags:

apis:
  version: "87"
  camunda_api:
    base_url: "http://localhost:8080/v2"
  operate_api:
    base_url: "http://localhost:8080"
  tasklist_api:
    base_url: "http://localhost:8080"

If you use Camunda 8 with OAuth2 (oidc) authentication

Ways to provide settings

c8volt uses Viper under the hood. Configuration values can come from:

• Flags (--auth-client-id=...)
• Environment variables (C8VOLT_AUTH_CLIENT_ID=...)
• Config file (YAML)
• Defaults (hardcoded fallbacks)

Precedence

When multiple sources define the same setting, the highest-priority value wins:

Default configuration file locations

When searching for a config file, c8volt checks these paths in order and uses the first one it finds:

File format

Config files must be YAML. You can inspect the effective configuration (after merging defaults, config file, env vars, and flags) with:

$ ./c8volt config show

You will see output like this:

apis:
    camunda_api:
        base_url: http://localhost:8080/v2
        key: camunda_api
        require_scope: false
    operate_api:
        base_url: http://localhost:8080
        key: operate_api
        require_scope: false
    tasklist_api:
        base_url: http://localhost:8080
        key: tasklist_api
        require_scope: false
    version: "8.8"
app:
    backoff:
        initial_delay: 5e+08
        max_delay: 8e+09
        max_retries: 0
        multiplier: 2
        strategy: exponential
        timeout: 5e+09
    tenant: ""
auth:
    cookie:
        base_url: http://localhost:8090
        password: '*****'
        username: ""
    mode: oauth2
    oauth2:
        client_id: c8volt
        client_secret: '*****'
        scopes:
            camunda_api: profile
            operate_api: profile
            tasklist_api: profile
        token_url: http://localhost:18080/auth/realms/camunda-platform/protocol/openid-connect
config: ""
http:
    timeout: 23s
log:
    format: plain
    level: debug
    with_request_body: false
    with_source: true

You can output the config as empty (no values) template with:

$ ./c8volt config show --template

In case of any issues with loading or parsing the config file, use validation with:

$ ./c8volt config show --validate

Environment variables

Each config key can also be set via environment variable.
The prefix is C8VOLT_, and nested keys are joined with _. For example:

• C8VOLT_AUTH_CLIENT_ID
• C8VOLT_AUTH_CLIENT_SECRET
• C8VOLT_HTTP_TIMEOUT

Security note

Sensitive fields such as auth.client_secret are always masked when the configuration is printed or logged. The raw values are still loaded and used internally, but they will never appear in output.

c8volt in Action

Look here for practical examples of using c8volt for common tasks and special use cases.

Deleting an active process instance by cancelling it first, if the instance is active

List all process instances for a specific process definition:

$ c8volt get pi --bpmn-process-id=C87SimpleUserTask_Process --one-line
found: 12
2251799813685511 dev01 C87SimpleUserTask_Process v1/v1.0.0 ACTIVE s:2025-09-09T12:14:30.380+0000 i:false
2251799813685518 dev01 C87SimpleUserTask_Process v1/v1.0.0 ACTIVE s:2025-09-09T12:14:36.618+0000 i:false
2251799813685525 dev01 C87SimpleUserTask_Process v1/v1.0.0 ACTIVE s:2025-09-09T12:14:40.675+0000 i:false
2251799813685532 dev01 C87SimpleUserTask_Process v1/v1.0.0 ACTIVE s:2025-09-09T12:14:44.338+0000 i:false
2251799813685541 dev01 C87SimpleUserTask_Process v2 ACTIVE s:2025-09-09T16:11:52.976+0000 i:false
2251799813685548 dev01 C87SimpleUserTask_Process v2 ACTIVE s:2025-09-09T16:13:30.653+0000 i:false
2251799813685556 dev01 C87SimpleUserTask_Process v2 ACTIVE s:2025-09-09T16:13:53.060+0000 i:false
2251799813685571 dev01 C87SimpleUserTask_Process v2 CANCELED s:2025-09-09T19:10:28.190+0000 e:2025-09-10T20:36:44.990+0000 p:2251799813685566 i:false
2251799813685582 dev01 C87SimpleUserTask_Process v2 CANCELED s:2025-09-09T19:10:33.364+0000 e:2025-09-09T20:27:55.530+0000 p:2251799813685577 i:false
2251799813685595 dev01 C87SimpleUserTask_Process v2 ACTIVE s:2025-09-09T22:01:27.621+0000 p:2251799813685590 i:false
2251799813685606 dev01 C87SimpleUserTask_Process v2 ACTIVE s:2025-09-09T22:01:33.533+0000 p:2251799813685601 i:false
2251799813685614 dev01 C87SimpleUserTask_Process v3 ACTIVE s:2025-09-10T10:03:12.700+0000 i:false

List only active process instances for the specific process definition in active state:

$ c8volt get pi --bpmn-process-id=C87SimpleUserTask_Process --one-line --state=active
filter: state=active
found: 10
2251799813685511 dev01 C87SimpleUserTask_Process v1/v1.0.0 ACTIVE s:2025-09-09T12:14:30.380+0000 i:false
2251799813685518 dev01 C87SimpleUserTask_Process v1/v1.0.0 ACTIVE s:2025-09-09T12:14:36.618+0000 i:false
2251799813685525 dev01 C87SimpleUserTask_Process v1/v1.0.0 ACTIVE s:2025-09-09T12:14:40.675+0000 i:false
2251799813685532 dev01 C87SimpleUserTask_Process v1/v1.0.0 ACTIVE s:2025-09-09T12:14:44.338+0000 i:false
2251799813685541 dev01 C87SimpleUserTask_Process v2 ACTIVE s:2025-09-09T16:11:52.976+0000 i:false
2251799813685548 dev01 C87SimpleUserTask_Process v2 ACTIVE s:2025-09-09T16:13:30.653+0000 i:false
2251799813685556 dev01 C87SimpleUserTask_Process v2 ACTIVE s:2025-09-09T16:13:53.060+0000 i:false
2251799813685595 dev01 C87SimpleUserTask_Process v2 ACTIVE s:2025-09-09T22:01:27.621+0000 p:2251799813685590 i:false
2251799813685606 dev01 C87SimpleUserTask_Process v2 ACTIVE s:2025-09-09T22:01:33.533+0000 p:2251799813685601 i:false
2251799813685614 dev01 C87SimpleUserTask_Process v3 ACTIVE s:2025-09-10T10:03:12.700+0000 i:false

Try to delete an active process instance (will fail):

$ c8volt delete pi --key 2251799813685511
trying to delete process instance with key 2251799813685511...
Error deleting process instance with key 2251799813685511: unexpected status 400: {"status":400,"message":"Process instances needs to be in one of the states [COMPLETED, CANCELED]","instance":"dae2c2ce-58dd-4396-a948-4d57463168ed","type":"Invalid request"}

Try to delete an active process instance by forcing cancellation first (will succeed):

$ c8volt delete pi --key 2251799813685511 --cancel
trying to delete process instance with key 2251799813685511...
process instance with key 2251799813685511 not in state COMPLETED or CANCELED, cancelling it first...
trying to cancel process instance with key 2251799813685511...
process instance with key 2251799813685511 was successfully cancelled
waiting for process instance with key 2251799813685511 to be cancelled by workflow engine...
process instance "2251799813685511" currently in state "ACTIVE"; waiting...
process instance "2251799813685511" currently in state "ACTIVE"; waiting...
process instance "2251799813685511" currently in state "ACTIVE"; waiting...
process instance "2251799813685511" currently in state "ACTIVE"; waiting...
process instance "2251799813685511" currently in state "ACTIVE"; waiting...
process instance "2251799813685511" reached desired state "CANCELED"
process instance with key 2251799813685511 was successfully deleted
{
  "deleted": 1,
  "message": "Process instance and dependant data deleted for key '2251799813685511'"
}

Finding process instances with orphan (non-existing) parent process instances

List all process instances for a specific process definition:

$ c8volt get pi --bpmn-process-id=C87SimpleUserTask_Process --one-line
found: 12
2251799813685511 dev01 C87SimpleUserTask_Process v1/v1.0.0 ACTIVE s:2025-09-09T12:14:30.380+0000 i:false
2251799813685518 dev01 C87SimpleUserTask_Process v1/v1.0.0 ACTIVE s:2025-09-09T12:14:36.618+0000 i:false
2251799813685525 dev01 C87SimpleUserTask_Process v1/v1.0.0 ACTIVE s:2025-09-09T12:14:40.675+0000 i:false
2251799813685532 dev01 C87SimpleUserTask_Process v1/v1.0.0 ACTIVE s:2025-09-09T12:14:44.338+0000 i:false
2251799813685541 dev01 C87SimpleUserTask_Process v2 ACTIVE s:2025-09-09T16:11:52.976+0000 i:false
2251799813685548 dev01 C87SimpleUserTask_Process v2 ACTIVE s:2025-09-09T16:13:30.653+0000 i:false
2251799813685556 dev01 C87SimpleUserTask_Process v2 ACTIVE s:2025-09-09T16:13:53.060+0000 i:false
2251799813685571 dev01 C87SimpleUserTask_Process v2 CANCELED s:2025-09-09T19:10:28.190+0000 e:2025-09-10T20:36:44.990+0000 p:2251799813685566 i:false
2251799813685582 dev01 C87SimpleUserTask_Process v2 CANCELED s:2025-09-09T19:10:33.364+0000 e:2025-09-09T20:27:55.530+0000 p:2251799813685577 i:false
2251799813685595 dev01 C87SimpleUserTask_Process v2 ACTIVE s:2025-09-09T22:01:27.621+0000 p:2251799813685590 i:false
2251799813685606 dev01 C87SimpleUserTask_Process v2 ACTIVE s:2025-09-09T22:01:33.533+0000 p:2251799813685601 i:false
2251799813685614 dev01 C87SimpleUserTask_Process v3 ACTIVE s:2025-09-10T10:03:12.700+0000 i:false

List all process instances for a specific process definition that are children of other process instances (look at p:...):

$ c8volt get pi --bpmn-process-id=C87SimpleUserTask_Process --one-line --children-only
filter: children-only=true
found: 4
2251799813685571 dev01 C87SimpleUserTask_Process v2 CANCELED s:2025-09-09T19:10:28.190+0000 e:2025-09-10T20:36:44.990+0000 p:2251799813685566 i:false
2251799813685582 dev01 C87SimpleUserTask_Process v2 CANCELED s:2025-09-09T19:10:33.364+0000 e:2025-09-09T20:27:55.530+0000 p:2251799813685577 i:false
2251799813685595 dev01 C87SimpleUserTask_Process v2 ACTIVE s:2025-09-09T22:01:27.621+0000 p:2251799813685590 i:false
2251799813685606 dev01 C87SimpleUserTask_Process v2 ACTIVE s:2025-09-09T22:01:33.533+0000 p:2251799813685601 i:false

List all process instances for a specific process definition that are children of orphan parent process instances (their parent process instance no longer exists):

$ c8volt get pi --bpmn-process-id=C87SimpleUserTask_Process --one-line --orphan-parents-only
filter: orphan-parents-only=true
found: 2
2251799813685571 dev01 C87SimpleUserTask_Process v2 CANCELED s:2025-09-09T19:10:28.190+0000 e:2025-09-10T20:36:44.990+0000 p:2251799813685566 i:false
2251799813685582 dev01 C87SimpleUserTask_Process v2 CANCELED s:2025-09-09T19:10:33.364+0000 e:2025-09-09T20:27:55.530+0000 p:2251799813685577 i:false

Listing process instances for a process definition in a specific version

List all process instances for a specific process definition:

$ c8volt get pi --bpmn-process-id=C87SimpleUserTask_Process --one-line
found: 11
2251799813685518 dev01 C87SimpleUserTask_Process v1/v1.0.0 ACTIVE s:2025-09-09T12:14:36.618+0000 i:false
2251799813685525 dev01 C87SimpleUserTask_Process v1/v1.0.0 ACTIVE s:2025-09-09T12:14:40.675+0000 i:false
2251799813685532 dev01 C87SimpleUserTask_Process v1/v1.0.0 ACTIVE s:2025-09-09T12:14:44.338+0000 i:false
2251799813685541 dev01 C87SimpleUserTask_Process v2 ACTIVE s:2025-09-09T16:11:52.976+0000 i:false
2251799813685548 dev01 C87SimpleUserTask_Process v2 ACTIVE s:2025-09-09T16:13:30.653+0000 i:false
2251799813685556 dev01 C87SimpleUserTask_Process v2 ACTIVE s:2025-09-09T16:13:53.060+0000 i:false
2251799813685571 dev01 C87SimpleUserTask_Process v2 CANCELED s:2025-09-09T19:10:28.190+0000 e:2025-09-10T20:36:44.990+0000 p:2251799813685566 i:false
2251799813685582 dev01 C87SimpleUserTask_Process v2 CANCELED s:2025-09-09T19:10:33.364+0000 e:2025-09-09T20:27:55.530+0000 p:2251799813685577 i:false
2251799813685595 dev01 C87SimpleUserTask_Process v2 ACTIVE s:2025-09-09T22:01:27.621+0000 p:2251799813685590 i:false
2251799813685606 dev01 C87SimpleUserTask_Process v2 ACTIVE s:2025-09-09T22:01:33.533+0000 p:2251799813685601 i:false
2251799813685614 dev01 C87SimpleUserTask_Process v3 ACTIVE s:2025-09-10T10:03:12.700+0000 i:false

List only process instances for version 1 of the process definition:

$ c8volt get pi --bpmn-process-id=C87SimpleUserTask_Process --one-line --process-version=1
found: 3
2251799813685518 dev01 C87SimpleUserTask_Process v1/v1.0.0 ACTIVE s:2025-09-09T12:14:36.618+0000 i:false
2251799813685525 dev01 C87SimpleUserTask_Process v1/v1.0.0 ACTIVE s:2025-09-09T12:14:40.675+0000 i:false
2251799813685532 dev01 C87SimpleUserTask_Process v1/v1.0.0 ACTIVE s:2025-09-09T12:14:44.338+0000 i:false

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