The base64 example

In this example, we demonstrate how to create and run a Rust function in the Second State Rust FaaS.

Prerequisites

If you have not done so already, follow these simple instructions to install Rust and ssvmup.

Build the WASM bytecode

$ ssvmup build

FaaS

Upload the wasm file in the pkg folder to the FaaS. Double check the .wasm file name before you upload.

$ curl --location --request POST 'https://rpc.ssvm.secondstate.io:8081/api/executables' \
--header 'Content-Type: application/octet-stream' \
--header 'SSVM-Description: base64' \
--data-binary '@pkg/base64_conv_lib_bg.wasm'

Returns

{"wasm_id":123,"wasm_sha256":"0xfb413547a8aba56d0349603a7989e269f3846245e51804932b3e02bc0be4b665","usage_key":"00000000-0000-0000-0000-000000000000","admin_key":"00xxxxxx-xxxx-xxxx-xxxx-4adc960fd2b8"}

Make a function

curl --location --request POST 'https://rpc.ssvm.secondstate.io:8081/api/run/123/encode' \
--header 'Content-Type: application/octet-stream' \
--data-binary '@test/one_pixel_png_image.png'

The above command creates the following text string

iVBORw0KGgoAAAANSUhEUgAAAAEAAAABAQMAAAAl21bKAAAAA1BMVEX/TQBcNTh/AAAAAXRSTlPM0jRW/QAAAApJREFUeJxjYgAAAAYAAzY3fKgAAAAASUVORK5CYII=

Make a reverse function call via the web, using the text from above as input.

Please note - we are calling the /bytes endpoint here. This is because the decode function of Rust source code returns bytes as apposed to the encode function which returned a string.

curl --location --request POST 'https://rpc.ssvm.secondstate.io:8081/api/run/123/decode/bytes' \
--header 'Content-Type: text/plain' \
--data-raw 'iVBORw0KGgoAAAANSUhEUgAAAAEAAAABAQMAAAAl21bKAAAAA1BMVEX/TQBcNTh/AAAAAXRSTlPM0jRW/QAAAApJREFUeJxjYgAAAAYAAzY3fKgAAAAASUVORK5CYII=' --output tmp.png

Confirm the conversion.

diff tmp.png test/one_pixel_png_image.png

USE url_safe mode

Set the context state to string url_safe for functions in this wasm file.

$ curl --location --request PUT 'https://rpc.ssvm.secondstate.io:8081/api/state/123' --header 'Content-Type: text/plain' --data-raw 'url_safe'

Make a function call via the web.

curl --location --request POST 'https://rpc.ssvm.secondstate.io:8081/api/run/123/encode' \
--header 'Content-Type: application/octet-stream' \
--data-binary '@test/one_pixel_png_image.png'

Make a reverse function call via the web.

Please note - we are again calling the /bytes endpoint here, because the decode function of Rust source code returns bytes as apposed to the encode function which returned a string.

curl --location --request POST 'https://rpc.ssvm.secondstate.io:8081/api/run/123/decode/bytes' \
--header 'Content-Type: text/plain' \
--data-raw 'iVBORw0KGgoAAAANSUhEUgAAAAEAAAABAQMAAAAl21bKAAAAA1BMVEX_TQBcNTh_AAAAAXRSTlPM0jRW_QAAAApJREFUeJxjYgAAAAYAAzY3fKgAAAAASUVORK5CYII=' --output tmp.png

Confirm the conversion.

diff tmp.png test/one_pixel_png_image.png