Appwrite Funcover

Right before Appwrite's releasing the next generation (4) of their functions, You can cover your Appwrite function with a dedicated endpoint!

With Funcover you can cover your function with any domain you want!

That means that you'll be able to access one of your Appwrite functions or all of them using any endpoint you want.

This feature will help you use Appwrite functions as a target-webhook, direct access URL (without the need to provide project id), And also simply, for your convince.

💥 Funcover is built with:

• Bun (Because I like it) - A fast all-in-one JavaScript runtime.
• Hono - Simple, ultrafast web framework.
• TypeScript - I'm speechless 😉

📖 Table of Contents:

• Funcover Features
• Installation
  • SSL
  • Domain based
  • Path based
  • A bit of explanation
• Usages
  • Post Requests
  • Logs
  • Global
  • Multiple Instances
  • Rate limiting
• Environment variables
  • API Keys
  • Flatten Headers
  • Path as Data

📃 Funcover features

• Access your Appwrite function through a GET request.
• User your Appwrite function as a Webhook.
• Passing all request headers.
• Passing all request Body/Form/Json data.
• Passing data query variable in GET requests.
• Can be used for single or all of your functions.
• Passing API Key.
• Access Funcover on custom path.

🧑‍💻 Installation

Funcover meant to be added to your current self-hosted Appwrite instance, and, this is what we going to cover in this page. However, you can use Funcover as a standalone Appwrite-Function proxy, and use some provider - Cloudflare, for example - to handle the SSL part for you.

🔒 SSL

If you're going to use Funcover in a Path Based mode you can skip this part.

Before adding Funcover you'll need make sure that the domain you're planning to use will have SSL, To do so we're harnessing Appwrite custom-domain feature.

After adding your domain as custom-domain to any of your Appwrite project, and, the domain is now pointing to your Appwrite instance you can move to the next step.

🌐 Adding Funcover - Domain Based

In Domain Based mode we want to be able to access Funcover using a completely different domain.

SSH into your server and edit your docker-compose.yml file.

At the bottom of the file right after the telegraf service, and, right before the networks section add the following.

  funcover:
    image: boolcode/appwrite-funcover:0.0.8
    container_name: funcover
    restart: unless-stopped
    environment:
      - ALLOW_GLOBAL=true
      - DEFAULT_PROJECT=yourDefaultProjectID
      - DEFAULT_FUNCTION=yourDefaultFunctionID
    networks:
      - appwrite
      - gateway
    labels:
      - traefik.enable=true
      - traefik.constraint-label-stack=appwrite
      - traefik.docker.network=appwrite
      - traefik.http.services.funcover.loadbalancer.server.port=3000
      - traefik.http.routers.funcover-http.entrypoints=appwrite_web
      - traefik.http.routers.funcover-http.rule=Host(`custom.domain.com`) && PathPrefix(`/`)
      - traefik.http.routers.funcover-http.service=funcover
      - traefik.http.routers.funcover-https.entrypoints=appwrite_websecure
      - traefik.http.routers.funcover-https.rule=Host(`custom.domain.com`) && PathPrefix(`/`)
      - traefik.http.routers.funcover-https.service=funcover
      - traefik.http.routers.funcover-https.tls=true

Replace custom.domain.com with your newly attached custom-domain.

Look here for a complete example.

✍️ Adding Funcover - Path Based

In Path Based mode we want to be able to access Funcover with current Appwrite domain, But, with a custom path.

Added in version 0.0.6

  funcover:
    image: boolcode/appwrite-funcover:0.0.8
    container_name: funcover
    restart: unless-stopped
    environment:
      - ALLOW_GLOBAL=true
      - DEFAULT_PROJECT=yourDefaultProjectID
      - DEFAULT_FUNCTION=yourDefaultFunctionID
    networks:
      - appwrite
      - gateway
    labels:
      - traefik.enable=true
      - traefik.constraint-label-stack=appwrite
      - traefik.docker.network=appwrite
      - traefik.http.services.funcover.loadbalancer.server.port=3000
      - traefik.http.routers.funcover-http.entrypoints=appwrite_web
      - traefik.http.routers.funcover-http.rule=PathPrefix(`/v1/webhook`)
      - traefik.http.routers.funcover-http.service=funcover
      - traefik.http.routers.funcover-https.entrypoints=appwrite_websecure
      - traefik.http.routers.funcover-https.rule=PathPrefix(`/v1/webhook`)
      - traefik.http.routers.funcover-https.service=funcover
      - traefik.http.routers.funcover-https.tls=true

Keep in mind that you'll need to add PATH_INSTEAD_OF_DOMAIN and PATH_PREFIX environment variables. check more here.

🦉️ Deep dive

What is going on that snippet, what we just did??

We have added a new service into the docker-compose.yml file, And, Here's a quick overview of the fields.

• image - The name of the Docker image we are using for this service.
• container_name - The name of the container. useful for logging and monitoring.
• restart - Container restart policy. We have set it to unless-stopped, So, unless we're stopping it Docker will make sure the service is on.
• environment - Here we're passing some values to be handled by Funcover at runtime. This is the best way to customize docker images without the need to rebuild them.
• networks - Here we're connecting Funcover to appwrite network.
• labels - Labels are piece of information that can be used by other containers,In this case the traefik one.

Do notice the service rule (for http & https)

.rule=Host(`custom.domain.com`) && PathPrefix(`/`)

We are setting two conditions for the rule.

1. Host - We want to match the host to access Funcover.
2. PathPrefix - Adding this part is important for the case we want Funcover to be able to parse all requests with no routes.

Be aware that when you're upgrading Appwrite this addition will be erased.

---

Now it's time to reload our Docker Compose environment by running,

docker compose up -d

🛠️ Usages

Now any time you'll access the custom-domain, your default function in your default project will run, And, Will return back the execution JSON. Just like you've used the createExecution function.

{
  "$id"         : "5e5ea5c16897e",
  "$createdAt"  : "2020-10-15T06:38:00.000+00:00",
  "$updatedAt"  : "2020-10-15T06:38:00.000+00:00",
  "$permissions": [
    "any"
  ],
  "functionId"  : "5e5ea6g16897e",
  "trigger"     : "http",
  "status"      : "processing",
  "statusCode"  : 0,
  "response"    : "",
  "stdout"      : "",
  "stderr"      : "",
  "duration"    : 0.4
}

For different return formats check the RETURN_TYPE variable here.

Passing data to the function can be done in any of the following four ways.

1. GET data variable. https://custom.domain.com/?data=data
2. GET parameter route as data. https://custom.domain.com/data
3. POST using raw data with application/json content type.
4. POST using form-data.
5. POST using application/x-www-form-urlencoded.

🗒️ Note for POST

Funcover will check first for raw JSON data before checking for form-data or application/x-www-form-urlencoded.

Also, You can use a filed named rawData to pass data directly to data key. Here's an example in JSON

{
  "rawData": "I'm piece of data"
}

This data will be sent to the function like so:

{
  "data": "I'm piece of data"
}

As in any other case, this one for example:

{
  "data": "I'm piece of data"
}

The data will be sent to the function completely, like so:

{
  "data": "{\"data\":\"I'm piece of data\"}"
}

📝 Logs

Funcover don't produce any logs at runtime. In case you want to debug Funcover steps, or you just want to know more, You can pass the VERBOSE environment variable in the docker-compose.yml file.

Then you'll be able to see the logs by running

docker logs funcover

You can add the -f flag to follow the log output.

🌎 Global

Funcover can be used for a single function by setting the DEFAULT_PROJECT & DEFAULT_FUNCTION variables.

Also, Funcover can be used to handle all of your functions by project and function ID.

To do so you'll need to set the ALLOW_GLOBAL variable as true and reload your Docker Compose environment.

Now you'll be able to access any of your functions by using the following route.

https://custom.domain.com/projectId/functionId/

Also, here, You pass the data in GET or POST as in the default function endpoint.

🎶 Multiple instances.

In case you like to use Funcover on single mode, and/or you want to have multiple Funcover instances you can do so.

In the attached example you can see how to set a second Funcover by looking on the funcover-second service.

🛑 Rate limiting & Permissions

As of now Funcover uses the REST Client-side SDK. That mean that each function will hit their client rate-limit after 60 execution in a given minute.

For most use-cases that will more than enough.

Also, because Funcover execute the function through Client-side, Make sure you're adding the Any execution permission for your function permissions.

If you want your function to run as many times as you like you can add project API key with the API_KEYS environment variable.

🏗️ Environment variables

You can take a look at .env.example for possible values

Variable	Usage
VERBOSE	When sets to true Funcover will produce more logs at runtime.
ALLOW_GLOBAL	When sets to true Funcover will handle all of your function by project id.
RETURN_TYPE	How would you like to get the function output back - normal - (Default) Just return the function output as JSON. - json - Returns the response part from the function as parsed JSON. - html - Returns the response part from the function as parsed HTML. - redirect - Redirect the user the response returned URL.
ENDPOINT	Set as your Appwrite endpoint. Funcover will work even if you didn't provide any endpoint, As Funcover will access the main Appwrite container through Docker-network internal host url, http://appwrite/v1.
DEFAULT_PROJECT	Set as your default Appwrite project ID.
DEFAULT_FUNCTION	Set as your default Appwrite function ID.
PATH_INSTEAD_OF_DOMAIN	When sets to true Funcover will add the value of PATH_PREFIX to all is routes. For example, when PATH_PREFIX is sets = v1/webhook then Funcover will deliver the default function in https://domain.com/v1/webhook instead of https://domain.com/ All other option - like ALLOW_GLOBAL for example - are available to use when using this option.
PATH_PREFIX	Set the path to will be add as prefix to all Funcover requests.
API_KEYS	In case you need your function to be able to run as many times as necessary, You can pass here an Appwrite API key that will be used when executing the function. Check this.
FLATTEN_HEADERS	When sets to true Funcover will insert all of the request headers as headers property inside your function payload. Check this.
PATH_AS_DATA	When sets to true Funcover will pass the following parameter as the function data. Check this.

API Key variable usages

The format of this variable is like so:

API_KEYS=someProjectId:someProjectKey,anotherProjectId:anotherProjectKey

First add the project ID, then the full API key seperated with the : colons character.

Then, if you want to another API key for another project, you can do so by separating these project keys with a , comma.

---

Flatten headers Key variable usages

Like so:

{
  "data": {
    "data"   : {},
    "headers": {}
  }
}

Notice your data will be sent recursively inside data.data property, and you'll to extract the data like so:

// First, Get the payload.
const payload = JSON.parse(req.payload);

// Second, parse the data and the headers.
const data    = JSON.parse(payload.data);
const headers = JSON.parse(payload.headers);

---

Path as data variable usages

You don't need to use the data variable like this

https://custom.domain.com/?data=data

You can just send it as the following route like so:

https://custom.domain.com/data

This will also work with the ALLOW_GLOBAL variable, so you can use it like this:

https://custom.domain.com/projectId/functionId/data