Status

This library is under construction. See api7#25 to know the progress.

Description

A Nginx module which tries to implement proxy wasm ABI in Nginx. The Wasm integration of Apache APISIX is powered by this module.

Install dependencies

• Download the wasmtime C API package and rename it to wasmtime-c-api/, with the ./install-wasmtime.sh. Remember to add the wasmtime-c-api/lib to the library search path when you build Nginx, for instance,

export wasmtime_prefix=/path/to/wasm-nginx-module/wasmtime-c-api
./configure ... \
    --with-ld-opt="-Wl,-rpath,${wasmtime_prefix}/lib" \

• Download WasmEdge with the ./install-wasmedge.sh. Remember to add the wasmedge/lib to the library search path when you build Nginx, for instance,

export wasmedge_prefix=/path/to/wasm-nginx-module/wasmedge
./configure ... \
    --with-ld-opt="-Wl,-rpath,${wasmedge_prefix}/lib" \

Directives

wasm_vm

syntax: wasm_vm wasmtime|wasmedge

default: -

context: http

Select the Wasm VM. Currently, only wasmtime and WasmEdge are supported. If the directive is not set, the Wasm VM won't be enabled.

Methods

Remember to set the wasm_vm directive!

load

syntax: plugin, err = proxy_wasm.load(name, path)

Load a .wasm file from the filesystem and return a Wasm plugin.

local plugin, err = proxy_wasm.load("plugin","t/testdata/plugin_lifecycle/main.go.wasm")

on_configure

syntax: plugin_ctx, err = proxy_wasm.on_configure(plugin, conf)

Create a plugin ctx with the given plugin and conf.

local plugin, err = proxy_wasm.load("plugin","t/testdata/plugin_lifecycle/main.go.wasm")
if not plugin then
    ngx.log(ngx.ERR, "failed to load wasm ", err)
    return
end
local ctx, err = wasm.on_configure(plugin, '{"body":512}')
if not ctx then
    ngx.log(ngx.ERR, "failed to create plugin ctx ", err)
    return
end

on_http_request_headers

syntax: ok, err = proxy_wasm.on_http_request_headers(plugin_ctx)

Run the HTTP request headers filter in the plugin of the given plugin ctx.

local plugin, err = proxy_wasm.load("plugin","t/testdata/plugin_lifecycle/main.go.wasm")
if not plugin then
    ngx.log(ngx.ERR, "failed to load wasm ", err)
    return
end
local ctx, err = wasm.on_configure(plugin, '{"body":512}')
if not ctx then
    ngx.log(ngx.ERR, "failed to create plugin ctx ", err)
    return
end
assert(wasm.on_http_request_headers(ctx))

on_http_request_body

syntax: ok, err = proxy_wasm.on_http_request_body(plugin_ctx, body, end_of_body)

Run the HTTP request body filter in the plugin of the given plugin ctx.

local plugin, err = proxy_wasm.load("plugin","t/testdata/plugin_lifecycle/main.go.wasm")
if not plugin then
    ngx.log(ngx.ERR, "failed to load wasm ", err)
    return
end
local ctx, err = wasm.on_configure(plugin, '{"body":512}')
if not ctx then
    ngx.log(ngx.ERR, "failed to create plugin ctx ", err)
    return
end
-- get_body is a utility method to get the whole request body
local body = request.get_body()
-- if the body is not the whole request body, for example, it comes from
-- lua-resty-upload, remember to set end_of_body to false
assert(wasm.on_http_request_body(ctx, body, true))

on_http_response_headers

syntax: ok, err = proxy_wasm.on_http_response_headers(plugin_ctx)

Run the HTTP response headers filter in the plugin of the given plugin ctx.

local plugin, err = proxy_wasm.load("plugin","t/testdata/http_lifecycle/main.go.wasm")
if not plugin then
    ngx.log(ngx.ERR, "failed to load wasm ", err)
    return
end
local ctx, err = wasm.on_configure(plugin, '{"body":512}')
if not ctx then
    ngx.log(ngx.ERR, "failed to create plugin ctx ", err)
    return
end
assert(wasm.on_http_response_headers(ctx))

on_http_response_body

syntax: ok, err = proxy_wasm.on_http_response_body(plugin_ctx)

Run the HTTP response body filter in the plugin of the given plugin ctx. This method need to be called in body_filter_by_lua phase and may be run multiple times.

local plugin, err = proxy_wasm.load("plugin","t/testdata/http_lifecycle/main.go.wasm")
if not plugin then
    ngx.log(ngx.ERR, "failed to load wasm ", err)
    return
end
local ctx, err = wasm.on_configure(plugin, '{"body":512}')
if not ctx then
    ngx.log(ngx.ERR, "failed to create plugin ctx ", err)
    return
end
assert(wasm.on_http_response_body(ctx))

proxy-wasm ABI

Implemented proxy-wasm ABI can be found in proxy_wasm_abi.