SSDK Command Line Interface
Stateful Services Developer Kit (ssdk) is a binary, shipped with fluvio, that helps developers build, test, and deploy stateful services. The first version works with Rust, and upcoming versions will enable Python and Javascript.
Commands
Download fluvio version manager (fvm), the package manager for fluvio and ssdk:
$ curl -fsS https://hub.infinyon.cloud/install/install.sh | bash
This command will download the Fluvio Version Manager (fvm), Fluvio CLI (fluvio) and config files into $HOME/.fluvio, with the executables in $HOME/.fluvio/bin. To complete the installation, you will need to add the executables to your shell $PATH.
Install the preview release:
$ fvm install ssdk-preview6
SSDK has the following comamand hierarchy:
$ ssdk -h
Stateful Service Development Kit utility
Usage: ssdk <COMMAND>
Commands:
build Build Stateful Service
clean Clean generated files from service directory
generate Generate SSDK projects from data-pipeline.yaml
update Update SSDK project
run Run Stateful Service
setup Setup pre-requisites for Stateful Service
version Display version information
log Print data pipeline logs
help Print this message or the help of the given subcommand(s)
Command line syntax for ssdk setup:
$ ssdk setup -h
Setup pre-requisites for Stateful Service
Usage: ssdk setup
Run ssdk setup to configure your local environment.
$ ssdk setup
Command line syntax for ssdk generate:
$ ssdk generate -h
Generate SSDK projects from data-pipeline.yaml
Usage: ssdk generate
SSDK generate requires a data-pipeline.yaml the current directory:
$ ssdk generate
The command parses the file and creates a Rust project in a subdirectory called project. For additional information, check out Data Pipeline File.
Command line syntax for ssdk build:
$ ssdk build -h
Build Stateful Service
Usage: ssdk build
The command builds the Rust project and generates all WASM Components.
$ ssdk build
Checkout the project directory to see the project hierarchy and the target components.
Command line syntax for ssdk update:
$ ssdk update -h
Update SSDK project
Usage: ssdk update [OPTIONS]
Options:
-f, --force force to apply all updates
-d, --dry-run print changes and exit
This command is used to update the project based on updated in the data-pipeline.yaml file.
The update command makes code changes that cannot be reversed. As a safety measure, the command generates a diff and asks for confirmation before proceeding. If you want to bypass the confirmation prompt, use the -f and -d flags.
Command line syntax for ssdk clean:
$ ssdk clean -h
Clean generated files from project directory
Usage: ssdk clean
This command is used to clean-up the project directory and start again.
Let’s say we made major changes to the data-pipeline.yaml file and the previous version is no longer relevant. We can use clean to remove the project and start over:
$ ssdk clean
Use ssdk log to view you print statements:
$ ssdk log -h
Print data pipeline logs
Usage: ssdk log [OPTIONS]
Options:
-f, --follow Specify if the logs should be streamed
Use --f --follow option to watch the logs.
The following code splits sentences into words and has a println statement:
- operator: flat-map
run: |
fn split_sentence(sentence: String) -> Result<Vec<String>, String> {
let result = sentence.split_whitespace().map(String::from).collect();
println!("{:?}", result);
Ok(result)
}
For the sentence with This is a test, the output will be:
$ ssdk log
2024-01-06T02:08:09.735861+00:00 split-sentence INFO ["This", "is", "a", "test"]
Command line syntax for ssdk version:
$ ssdk version -h
Display version information
Usage: ssdk version
Find out what version you are running:
$ ssdk version
Run the project and open the command line in interactive mode with ssdk run:
$ ssdk run -h
Run Stateful Service
Usage: ssdk run [OPTIONS]
Options:
--ui start the workflow viewer ui [env: UI=]
-p, --port <PORT> port for web server to listen on [env: PORT=] [default: 8000]
Use --ui to view a graphical represetation of the project in a web browser. The default port is 8000, and you may change it with the --port flag.
Navigate to the project directory, ensure it’s built, and run to start the project in interactive mode:
$ ssdk run --ui
Please visit http://127.0.0.1:8000 to use SSDK Studio
...
SSDK run opens the command line in interactive mode:
>> -h
SSDK - Stateful Service Development Kit
Usage: <COMMAND>
Commands:
show Show or List states. Use `show state --help` for more info
exit Stop interactive session
Use show state to peak into the internal state objects managed by the system:
Command line syntax for show state:
>> show state -h
List all states or show state for given key
Usage: show state [OPTIONS] [NAMESPACE]
Arguments:
[NAMESPACE] namespace of state
Options:
--key <KEY> key of state
--filter <FILTER> filter regex
For example, to show all state objects:
>> show state
Namespace Keys Type
word-processing-window/count-per-word/state 22 u32
word-processing-window/sentence/topic.offset 1 offset
The states are organized by namespace where the first keyword is the service name word-processing-window, followed by the function name count-per-word or topic sentence. The state is the temporary result computed by the window function, whereas topic.offset is the offset of the last record read from the sentence topic.
To further inspect the objects, use the show state command with the name of the namespace:
>> show state word-processing-window/count-per-word/state
Key Value Window
book 1 2023-12-28T00:32:00Z:2023-12-28T00:32:20Z
but 1 2023-12-28T00:32:00Z:2023-12-28T00:32:20Z
...
You also have the option to filter the state by key (--key), or a regex (--filter) operation.
Exit interactive mode:
>> exit
bye!