blobby

Blobby

This component (we like to call it "Little Blobby Tables") is a simple file server showing the basic CRUD operations of the wasi:blobstore contract.

Not only is this component an example, it is also a fully-functional, HTTP-based fileserver that can be fronted with any HTTP server implementation and any blobstore implementation (i.e. you could store the uploaded files on a filesystem or in an s3 compatible store).

Prerequisites

• cargo 1.75
• wash 0.26.0

Building

wash build

Running with wasmCloud

Ensuring you've built your component with wash build, you can launch wasmCloud and deploy the full hello world application with the following commands. Once the application reports as Deployed in the application list, you can use curl to send a request to the running HTTP server.

wash up -d
wash app deploy ./wadm.yaml
wash app get
curl http://localhost:8000

Required Capabilities

1. wasi:http to receive http requests
2. wasi:blobstore to save the image to a blob
3. wasi:logging so the component can log

Once everything is up and running, you can run through all of the operations by following the annotated commands below:

# Create a file with some content
$ echo 'Hello there!' > myfile.txt

# Upload the file to the fileserver
$ curl -H 'Content-Type: text/plain' -v 'http://127.0.0.1:8000/myfile.txt' --data-binary @myfile.txt
*   Trying 127.0.0.1:8000...
* Connected to 127.0.0.1 (127.0.0.1) port 8000 (#0)
> POST /myfile.txt HTTP/1.1
> Host: 127.0.0.1:8000
> User-Agent: curl/7.85.0
> Accept: */*
> Content-Type: text/plain
> Content-Length: 12
>
* Mark bundle as not supporting multiuse
< HTTP/1.1 200 OK
< content-length: 0
< date: Wed, 18 Jan 2023 23:12:56 GMT
<
* Connection #0 to host 127.0.0.1 left intact

# Get the file back from the server
$ curl -v 'http://127.0.0.1:8000/myfile.txt'
*   Trying 127.0.0.1:8000...
* Connected to 127.0.0.1 (127.0.0.1) port 8000 (#0)
> GET /myfile.txt HTTP/1.1
> Host: 127.0.0.1:8000
> User-Agent: curl/7.85.0
> Accept: */*
>
* Mark bundle as not supporting multiuse
< HTTP/1.1 200 OK
< content-length: 13
< date: Wed, 18 Jan 2023 23:24:24 GMT
<
Hello there!
* Connection #0 to host 127.0.0.1 left intact

# Update the file
$ echo 'General Kenobi!' >> myfile.txt
$ curl -H 'Content-Type: text/plain' -v 'http://127.0.0.1:8000/myfile.txt' --data-binary @myfile.txt
*   Trying 127.0.0.1:8000...
* Connected to 127.0.0.1 (127.0.0.1) port 8000 (#0)
> POST /myfile.txt HTTP/1.1
> Host: 127.0.0.1:8000
> User-Agent: curl/7.85.0
> Accept: */*
> Content-Type: text/plain
> Content-Length: 29
>
* Mark bundle as not supporting multiuse
< HTTP/1.1 200 OK
< content-length: 0
< date: Wed, 18 Jan 2023 23:25:18 GMT
<
* Connection #0 to host 127.0.0.1 left intact

# Get the file again to see your updates
$ curl -v 'http://127.0.0.1:8000/myfile.txt'
*   Trying 127.0.0.1:8000...
* Connected to 127.0.0.1 (127.0.0.1) port 8000 (#0)
> GET /myfile.txt HTTP/1.1
> Host: 127.0.0.1:8000
> User-Agent: curl/7.85.0
> Accept: */*
>
* Mark bundle as not supporting multiuse
< HTTP/1.1 200 OK
< content-length: 29
< date: Wed, 18 Jan 2023 23:26:17 GMT
<
Hello there!
General Kenobi!
* Connection #0 to host 127.0.0.1 left intact

# Delete the file
$ curl -X DELETE -v 'http://127.0.0.1:8000/myfile.txt'
*   Trying 127.0.0.1:8000...
* Connected to 127.0.0.1 (127.0.0.1) port 8000 (#0)
> DELETE /myfile.txt HTTP/1.1
> Host: 127.0.0.1:8000
> User-Agent: curl/7.85.0
> Accept: */*
>
* Mark bundle as not supporting multiuse
< HTTP/1.1 200 OK
< content-length: 0
< date: Wed, 18 Jan 2023 23:33:02 GMT
<
* Connection #0 to host 127.0.0.1 left intact

# (Optional) See that the file doesn't exist anymore
$ curl -v 'http://127.0.0.1:8000/myfile.txt'
*   Trying 127.0.0.1:8000...
* Connected to 127.0.0.1 (127.0.0.1) port 8000 (#0)
> GET /myfile.txt HTTP/1.1
> Host: 127.0.0.1:8000
> User-Agent: curl/7.85.0
> Accept: */*
>
* Mark bundle as not supporting multiuse
< HTTP/1.1 404 Not Found
< content-length: 0
< date: Wed, 18 Jan 2023 23:39:07 GMT
<
* Connection #0 to host 127.0.0.1 left intact