mirror of
https://gitcode.com/JianFeeeee/ModelRouter.git
synced 2026-09-20 08:57:57 +00:00
fix: tool call anchor & wire format, streaming chunk passthrough, WebUI narrow-screen, docs bilingual
This commit is contained in:
271
docs/lua-adapters-en.md
Normal file
271
docs/lua-adapters-en.md
Normal file
@ -0,0 +1,271 @@
|
||||
# Lua Adapter API
|
||||
|
||||
> **中文**: [lua-adapters.md](./lua-adapters.md)
|
||||
|
||||
Every upstream source is mounted with a `.lua` adapter that **transforms** the unified
|
||||
OpenAI-format request into the upstream's native format, and converts upstream
|
||||
responses / stream chunks back into the unified format. The Go layer only handles
|
||||
scheduling, concurrency and pass-through — so **adding an adapter or adapting a new
|
||||
protocol never requires recompiling Go**.
|
||||
|
||||
Adapters live in two equivalent places:
|
||||
- Bundled: `internal/lua/adapters/<name>.lua` (embedded at build time)
|
||||
- Override: a same-named script in the configured `adapter_dir` (takes precedence)
|
||||
|
||||
> **When are they loaded?** All adapters are loaded once at startup by
|
||||
> `lua.NewVM(adapter_dir)`. Adapters uploaded via the WebUI
|
||||
> (`Core.UploadAdapter` → `vm.LoadAdapter`) and sources edited online take
|
||||
> effect immediately, without a restart. Directly editing a `.lua` file under
|
||||
> `adapter_dir` requires a process restart to reload.
|
||||
|
||||
## Table of Contents
|
||||
|
||||
1. [Script Structure](#1-script-structure)
|
||||
2. [Static Fields](#2-static-fields)
|
||||
3. [Transform Hooks](#3-transform-hooks)
|
||||
4. [Optional Hooks](#4-optional-hooks)
|
||||
5. [Built-in Helper Functions](#5-built-in-helper-functions)
|
||||
6. [meta Contract](#6-meta-contract)
|
||||
7. [A Complete Minimal Adapter](#7-a-complete-minimal-adapter)
|
||||
8. [Multimodal & disable_thinking](#8-multimodal--disable_thinking)
|
||||
|
||||
---
|
||||
|
||||
## 1. Script Structure
|
||||
|
||||
A script is a Lua file that returns a table — it **must** `return` a table:
|
||||
|
||||
```lua
|
||||
local adapter = {}
|
||||
adapter.name = "mysrc"
|
||||
adapter.version = "1.0.0"
|
||||
-- ... fields and functions ...
|
||||
return adapter
|
||||
```
|
||||
|
||||
Scripts are executed by LuaJIT (via golua bindings, cgo). Each adapter owns an
|
||||
**independent VM + worker pool**; adapters never interfere with each other. No mutable
|
||||
state may be shared across workers (`log` to stdout is the only side effect).
|
||||
|
||||
## 2. Static Fields
|
||||
|
||||
| Field | Type | Required | Description |
|
||||
|-------|------|----------|-------------|
|
||||
| `name` | string | yes | Adapter name, shown in the WebUI |
|
||||
| `version` | string | no | Version, shown in the WebUI |
|
||||
| `endpoint` | string | no | Upstream path, default `/chat/completions`; overridable by `source.endpoint` / `source.image_endpoint` |
|
||||
| `headers` | table | no | Static default request headers; used as fallback when no `build_headers` hook is defined |
|
||||
|
||||
These fields are extracted statically at load time (compile-once); reading them never
|
||||
occupies a pooled worker.
|
||||
|
||||
## 3. Transform Hooks
|
||||
|
||||
### `transform_request(raw_body) -> string`
|
||||
|
||||
Input: the unified OpenAI-format JSON string built by the Go layer (the
|
||||
`/v1/chat/completions` request body).
|
||||
Output: the request body string to send upstream.
|
||||
|
||||
```lua
|
||||
function adapter.transform_request(raw_body)
|
||||
local ok, req = pcall(json.decode, raw_body)
|
||||
if not ok then return raw_body end
|
||||
req.model = "upstream-model-name" -- rewrite the model name
|
||||
req.stream = req.stream or false
|
||||
return json.encode(req)
|
||||
end
|
||||
```
|
||||
|
||||
Contract:
|
||||
- The returned string is POSTed verbatim to `base_url + (source.endpoint or adapter.endpoint)`.
|
||||
- Internal gateway fields such as `disable_thinking` and `extra_body` should be cleaned
|
||||
up by the transform (`openai.lua` deletes both).
|
||||
|
||||
### `transform_response(raw_body) -> string`
|
||||
|
||||
Input: the raw JSON string of a non-streaming upstream response.
|
||||
Output: a JSON string in the unified format.
|
||||
|
||||
Unified format fields:
|
||||
|
||||
| Field | Type | Description |
|
||||
|-------|------|-------------|
|
||||
| `content` | string | Response text |
|
||||
| `finish_reason` | string | `stop` / `length` / `tool_calls` etc. |
|
||||
| `reasoning_content` | string (optional) | Reasoning text (DeepSeek etc.) |
|
||||
| `token_usage` | table | `{ prompt, completion, total }` (tokens) |
|
||||
| `tool_calls` | array (optional) | Tool calls: `{ id, type, name, arguments }`; `arguments` is a **decoded** table |
|
||||
|
||||
```lua
|
||||
function adapter.transform_response(raw_body)
|
||||
local ok, resp = pcall(json.decode, raw_body)
|
||||
if not ok or resp == nil then return raw_body end
|
||||
local unified = {
|
||||
content = "",
|
||||
finish_reason = "",
|
||||
token_usage = { prompt = 0, completion = 0, total = 0 }
|
||||
}
|
||||
if type(resp.choices) == "table" and #resp.choices > 0 then
|
||||
local ch = resp.choices[1]
|
||||
unified.content = ch.message.content or ""
|
||||
unified.finish_reason = ch.finish_reason or ""
|
||||
if ch.message.reasoning_content then
|
||||
unified.reasoning_content = ch.message.reasoning_content
|
||||
end
|
||||
end
|
||||
return json.encode(unified)
|
||||
end
|
||||
```
|
||||
|
||||
### `transform_stream_chunk(raw_chunk) -> string`
|
||||
|
||||
Input: the raw JSON string of each `data:` line in the SSE stream (without the
|
||||
`data:` prefix).
|
||||
Output: a unified chunk JSON string; **returning `""` skips that chunk**.
|
||||
|
||||
Unified chunk format:
|
||||
|
||||
| Field | Type | Description |
|
||||
|-------|------|-------------|
|
||||
| `content` | string | Incremental text for this chunk (may be `""`) |
|
||||
| `done` | boolean (optional) | `true` ends the stream (when `finish_reason` appears) |
|
||||
|
||||
```lua
|
||||
function adapter.transform_stream_chunk(raw_chunk)
|
||||
local ok, chunk = pcall(json.decode, raw_chunk)
|
||||
if not ok then return "" end
|
||||
if not chunk.choices or #chunk.choices == 0 then return "" end
|
||||
local delta = chunk.choices[1].delta or {}
|
||||
local fr = chunk.choices[1].finish_reason
|
||||
return json.encode({
|
||||
content = delta.content or "",
|
||||
done = (fr ~= nil)
|
||||
})
|
||||
end
|
||||
```
|
||||
|
||||
## 4. Optional Hooks
|
||||
|
||||
### `build_headers(meta) -> table<string,string>`
|
||||
|
||||
Dynamically generate / sign request headers (e.g. KimiCode's HMAC signature). If the
|
||||
script does not define this function, the Go layer falls back to the static
|
||||
`adapter.headers` (or `source.headers`).
|
||||
|
||||
```lua
|
||||
function adapter.build_headers(meta)
|
||||
local msg = meta.method .. meta.url .. meta.body
|
||||
return {
|
||||
["X-App-Sign"] = hmac_sha256_hex(meta.source.meta.app_secret, msg),
|
||||
["X-Timestamp"] = meta.timestamp,
|
||||
}
|
||||
end
|
||||
```
|
||||
|
||||
Returning a non-table errors; returning `{}` means no custom headers (no fallback to
|
||||
static headers).
|
||||
|
||||
## 5. Built-in Helper Functions
|
||||
|
||||
Global functions shared by all adapters (injected by Go):
|
||||
|
||||
| Function | Description |
|
||||
|----------|-------------|
|
||||
| `json.encode(v)` | Lua value → JSON string; returns `"null"` on failure |
|
||||
| `json.decode(s)` | JSON string → Lua value; returns `nil` on failure |
|
||||
| `hmac_sha256_hex(key, data)` | HMAC-SHA256, lowercase hex string |
|
||||
| `sha256_hex(data)` | SHA-256, lowercase hex string |
|
||||
| `base64_encode(s)` | Standard Base64 encoding |
|
||||
| `tohex(s)` | Bytes → lowercase hex string |
|
||||
| `log(level, msg)` | Prints `[adapter/<name>] <msg>` to stdout |
|
||||
|
||||
Note: scripts run under LuaJIT with the full standard library (`string`/`table`/`pcall`
|
||||
etc.); `os`/`io` are not exposed (sandbox semantics).
|
||||
|
||||
## 6. meta Contract
|
||||
|
||||
The meta structure shared by `build_headers(meta)` and the request transforms:
|
||||
|
||||
| Field | Description |
|
||||
|-------|-------------|
|
||||
| `meta.url` | Full request URL |
|
||||
| `meta.method` | HTTP method (usually `POST`) |
|
||||
| `meta.body` | Request body string |
|
||||
| `meta.api_key` | The source's `api_key` |
|
||||
| `meta.timestamp` | Request timestamp |
|
||||
| `meta.source` | table: `{ name, meta = { ... } }` — the source's `meta` field (e.g. `app_secret`) |
|
||||
|
||||
## 7. A Complete Minimal Adapter
|
||||
|
||||
```lua
|
||||
local adapter = {}
|
||||
|
||||
adapter.name = "mysrc"
|
||||
adapter.version = "1.0.0"
|
||||
adapter.endpoint = "/chat/completions"
|
||||
adapter.headers = { ["X-Tenant"] = "prod" }
|
||||
|
||||
function adapter.transform_request(raw_body)
|
||||
local ok, req = pcall(json.decode, raw_body)
|
||||
if not ok then return raw_body end
|
||||
req.disable_thinking = nil
|
||||
req.extra_body = nil
|
||||
return json.encode(req)
|
||||
end
|
||||
|
||||
function adapter.transform_response(raw_body)
|
||||
local ok, resp = pcall(json.decode, raw_body)
|
||||
if not ok or resp == nil then return raw_body end
|
||||
local unified = {
|
||||
content = "",
|
||||
finish_reason = "",
|
||||
token_usage = { prompt = 0, completion = 0, total = 0 }
|
||||
}
|
||||
if type(resp.choices) == "table" and #resp.choices > 0 then
|
||||
local ch = resp.choices[1]
|
||||
unified.content = ch.message.content or ""
|
||||
unified.finish_reason = ch.finish_reason or ""
|
||||
end
|
||||
return json.encode(unified)
|
||||
end
|
||||
|
||||
function adapter.transform_stream_chunk(raw_chunk)
|
||||
local ok, chunk = pcall(json.decode, raw_chunk)
|
||||
if not ok then return "" end
|
||||
if not chunk.choices or #chunk.choices == 0 then return "" end
|
||||
return json.encode({
|
||||
content = (chunk.choices[1].delta or {}).content or "",
|
||||
done = (chunk.choices[1].finish_reason ~= nil)
|
||||
})
|
||||
end
|
||||
|
||||
return adapter
|
||||
```
|
||||
|
||||
Corresponding `config.yaml` source:
|
||||
|
||||
```yaml
|
||||
sources:
|
||||
- name: mysrc
|
||||
base_url: https://upstream.example.com
|
||||
api_key: sk-xxx
|
||||
adapter: mysrc # or omit = bundled adapter with the same name
|
||||
endpoint: /chat/completions
|
||||
models:
|
||||
- id: my-model
|
||||
priority: 50
|
||||
kind: chat
|
||||
```
|
||||
|
||||
## 8. Multimodal & disable_thinking
|
||||
|
||||
- **Multimodal**: if the request `content` is an array
|
||||
(`[{type:"text"...},{type:"image_url"...}]`), the Go layer passes it through
|
||||
verbatim to the adapter. Sources whose protocol doesn't support it (Anthropic /
|
||||
Gemini / Ollama) must convert inside `transform_request`; the bundled
|
||||
`anthropic.lua` / `gemini.lua` / `ollama.lua` already do.
|
||||
- **disable_thinking**: the gateway passes `disable_thinking:true` from the request
|
||||
body into `transform_request`. The DeepSeek adapter maps it to
|
||||
`extra_body.thinking = { type = "disabled" }` and cleans up its own field; other
|
||||
adapters handle it per their protocol (implement or ignore as needed).
|
||||
Reference in New Issue
Block a user