Version: 2.11

azure-functions

Summary

Name

azure-functions is a serverless plugin built into Apache APISIX for seamless integration with Azure Serverless Function as a dynamic upstream to proxy all requests for a particular URI to the Microsoft Azure cloud, one of the most used public cloud platforms for production environment. If enabled, this plugin terminates the ongoing request to that particular URI and initiates a new request to the azure faas (the new upstream) on behalf of the client with the suitable authorization details set by the users, request headers, request body, params ( all these three components are passed from the original request ) and returns the response body, status code and the headers back to the original client that has invoked the request to the APISIX agent.

Attributes

NameTypeRequirementDefaultValidDescription
function_uristringrequiredThe azure function endpoint which triggers the serverless function code (eg. http://test-apisix.azurewebsites.net/api/HttpTrigger).
authorizationobjectoptionalAuthorization credentials to access the cloud function.
authorization.apikeystringoptionalField inside authorization. The generate API Key to authorize requests to that endpoint.
authorization.clientidstringoptionalField inside authorization. The Client ID ( azure active directory ) to authorize requests to that endpoint.
timeoutintegeroptional3000[100,…]Proxy request timeout in milliseconds.
ssl_verifybooleanoptionaltruetrue/falseIf enabled performs SSL verification of the server.
keepalivebooleanoptionaltruetrue/falseTo reuse the same proxy connection in near future. Set to false to disable keepalives and immediately close the connection.
keepalive_poolintegeroptional5[1,…]The maximum number of connections in the pool.
keepalive_timeoutintegeroptional60000[1000,…]The maximal idle timeout (ms).

Metadata

NameTypeRequirementDefaultValidDescription
master_apikeystringoptional“”The API KEY secret that could be used to access the azure function uri.
master_clientidstringoptional“”The Client ID (active directory) that could be used the authorize the function uri

Metadata for azure-functions plugin provides the functionality for authorization fallback. It defines master_apikey and master_clientid (azure active directory client id) where users (optionally) can define the master API key or Client ID for mission-critical application deployment. So if there are no authorization details found inside the plugin attribute the authorization details present in the metadata kicks in.

The relative priority ordering is as follows:

  • First, the plugin looks for x-functions-key or x-functions-clientid keys inside the request header to the APISIX agent.
  • If they are not found, the azure-functions plugin checks for the authorization details inside plugin attributes. If present, it adds the respective header to the request sent to the Azure cloud function.
  • If no authorization details are found inside plugin attributes, APISIX fetches the metadata config for this plugin and uses the master keys.

To add a new Master APIKEY, make a request to /apisix/admin/plugin_metadata endpoint with the updated metadata as follows:

  1. $ curl http://127.0.0.1:9080/apisix/admin/plugin_metadata/azure-functions -H 'X-API-KEY: edd1c9f034335f136f87ad84b625c8f1' -X PUT -d '
  2. {
  3.     "master_apikey" : "<Your azure master access key>"
  4. }'

How To Enable

The following is an example of how to enable the azure-function faas plugin for a specific route URI. We are assuming your cloud function is already up and running.

  1. # enable azure function for a route
  2. curl http://127.0.0.1:9080/apisix/admin/routes/1 -H 'X-API-KEY: edd1c9f034335f136f87ad84b625c8f1' -X PUT -d '
  3. {
  4.     "plugins": {
  5.         "azure-functions": {
  6.             "function_uri": "http://test-apisix.azurewebsites.net/api/HttpTrigger",
  7.             "authorization": {
  8.                 "apikey": "<Generated API key to access the Azure-Function>"
  9.             }
  10.         }
  11.     },
  12.     "uri": "/azure"
  13. }'

Now any requests (HTTP/1.1, HTTPS, HTTP2) to URI /azure will trigger an HTTP invocation to the aforesaid function URI and response body along with the response headers and response code will be proxied back to the client. For example ( here azure cloud function just take the name query param and returns Hello $name ) :

  1. $ curl -i -XGET http://localhost:9080/azure\?name=apisix
  2. HTTP/1.1 200 OK
  3. Content-Type: text/plain; charset=utf-8
  4. Transfer-Encoding: chunked
  5. Connection: keep-alive
  6. Request-Context: appId=cid-v1:38aae829-293b-43c2-82c6-fa94aec0a071
  7. Date: Wed, 17 Nov 2021 14:46:55 GMT
  8. Server: APISIX/2.10.2
  11. Hello, apisix

For requests where the mode of communication between the client and the Apache APISIX gateway is HTTP/2, the example looks like ( make sure you are running APISIX agent with enable_http2: true for a port in conf.yaml or uncomment port 9081 of node_listen field inside config-default.yaml ) :

  1. $ curl -i -XGET --http2 --http2-prior-knowledge http://localhost:9081/azure\?name=apisix
  2. HTTP/2 200
  3. content-type: text/plain; charset=utf-8
  4. request-context: appId=cid-v1:38aae829-293b-43c2-82c6-fa94aec0a071
  5. date: Wed, 17 Nov 2021 14:54:07 GMT
  6. server: APISIX/2.10.2
  9. Hello, apisix

Disable Plugin

Remove the corresponding JSON configuration in the plugin configuration to disable the azure-functions plugin and add the suitable upstream configuration. APISIX plugins are hot-reloaded, therefore no need to restart APISIX.

  1. $ curl http://127.0.0.1:9080/apisix/admin/routes/1 -H 'X-API-KEY: edd1c9f034335f136f87ad84b625c8f1' -X PUT -d '
  2. {
  3.     "uri": "/azure",
  4.     "plugins": {},
  5.     "upstream": {
  6.         "type": "roundrobin",
  7.         "nodes": {
  8.             "127.0.0.1:1980": 1
  9.         }
  10.     }
  11. }'