mirror of
https://github.com/openfaas/faas.git
synced 2025-06-10 01:06:47 +00:00
19e7f4639e
Also bumps golang builder version to 1.9.4 for sample functions. Signed-off-by: John McCabe <john@johnmccabe.net>
96 lines
2.6 KiB
Markdown
96 lines
2.6 KiB
Markdown
## Develop your own function
|
|
|
|
### TestDrive
|
|
|
|
Before you start development, you may want to take FaaS for a test drive which sets up a stack of sample functions from docker-compose.yml. You can then build your own functions and add them to the stack.
|
|
|
|
> You can test-drive FaaS with a set of sample functions as defined in docker-compose.yml on play-with-docker.com for free, or on your own laptop.
|
|
|
|
* [Begin the TestDrive instructions](https://github.com/openfaas/faas/blob/master/TestDrive.md)
|
|
|
|
### Working on the API Gateway or Watchdog
|
|
|
|
To work on either of the FaaS Golang components checkout the "./build.sh" scripts and acompanying Dockerfiles.
|
|
|
|
* [Roadmap and Contributing](https://github.com/openfaas/faas/blob/master/ROADMAP.md)
|
|
|
|
### Creating a function
|
|
|
|
Functions run as Docker containers with the Watchdog component embedded to handle communication with the API Gateway.
|
|
|
|
You can find the [reference documentation for the Watchdog here](https://github.com/openfaas/faas/tree/master/watchdog).
|
|
|
|
|
|
**Markdown Parser**
|
|
|
|
This is the basis of a function which generates HTML from MarkDown:
|
|
|
|
```
|
|
FROM golang:1.9.4
|
|
RUN mkdir -p /go/src/app
|
|
COPY handler.go /go/src/app
|
|
WORKDIR /go/src/app
|
|
RUN go get github.com/microcosm-cc/bluemonday && \
|
|
go get github.com/russross/blackfriday
|
|
|
|
RUN CGO_ENABLED=0 GOOS=linux go build -a -installsuffix cgo -o app .
|
|
|
|
ADD https://github.com/openfaas/faas/releases/download/0.7.1/fwatchdog /usr/bin
|
|
RUN chmod +x /usr/bin/fwatchdog
|
|
|
|
ENV fprocess="/go/src/app/app"
|
|
|
|
CMD ["/usr/bin/fwatchdog"]
|
|
```
|
|
|
|
The base Docker container is not important, you just need to add the watchdog component and then set the fprocess to execute your binary at runtime.
|
|
|
|
Update the Docker stack with this:
|
|
|
|
```
|
|
markdown:
|
|
image: alexellis2/faas-markdownrender:latest
|
|
labels:
|
|
function: "true"
|
|
networks:
|
|
- functions
|
|
```
|
|
|
|
**Word counter with busybox**
|
|
|
|
```
|
|
FROM alpine:latest
|
|
|
|
ADD https://github.com/openfaas/faas/releases/download/0.7.1/fwatchdog /usr/bin
|
|
RUN chmod +x /usr/bin/fwatchdog
|
|
|
|
ENV fprocess="wc"
|
|
CMD ["fwatchdog"]
|
|
```
|
|
|
|
Update your Docker stack with this definition:
|
|
|
|
```
|
|
wordcount:
|
|
image: alexellis2/faas-alpinefunction:latest
|
|
labels:
|
|
function: "true"
|
|
networks:
|
|
- functions
|
|
environment:
|
|
fprocess: "wc"
|
|
```
|
|
|
|
### Testing your function
|
|
|
|
You can test your function through a webbrowser against the UI portal on port 8080.
|
|
|
|
http://localhost:8080/
|
|
|
|
You can also invoke a function by name with curl:
|
|
|
|
```
|
|
curl --data-binary @README.md http://localhost:8080/function/func_wordcount
|
|
```
|
|
|