worker/
env.rs

1use std::fmt::Display;
2
3use crate::analytics_engine::AnalyticsEngineDataset;
4#[cfg(feature = "d1")]
5use crate::d1::D1Database;
6#[cfg(feature = "queue")]
7use crate::Queue;
8use crate::{durable::ObjectNamespace, Bucket, DynamicDispatcher, Fetcher, Result, SecretStore};
9use crate::{error::Error, hyperdrive::Hyperdrive};
10
11use crate::Ai;
12
13use js_sys::Object;
14use serde::de::DeserializeOwned;
15use wasm_bindgen::{prelude::*, JsCast, JsValue};
16use worker_kv::KvStore;
17
18#[wasm_bindgen]
19extern "C" {
20    /// Env contains any bindings you have associated with the Worker when you uploaded it.
21    #[derive(Debug, Clone)]
22    pub type Env;
23}
24
25unsafe impl Send for Env {}
26unsafe impl Sync for Env {}
27
28impl Env {
29    /// Access a binding that does not have a wrapper in workers-rs. Useful for internal-only or
30    /// unstable bindings.
31    pub fn get_binding<T: EnvBinding>(&self, name: &str) -> Result<T> {
32        let binding = js_sys::Reflect::get(self, &JsValue::from(name))
33            .map_err(|_| Error::JsError(format!("Env does not contain binding `{name}`")))?;
34        if binding.is_undefined() {
35            Err(format!("Binding `{name}` is undefined.").into())
36        } else {
37            // Can't just use JsCast::dyn_into here because the type name might not be in scope
38            // resulting in a terribly annoying javascript error which can't be caught
39            T::get(binding)
40        }
41    }
42
43    pub fn ai(&self, binding: &str) -> Result<Ai> {
44        self.get_binding::<Ai>(binding)
45    }
46
47    pub fn analytics_engine(&self, binding: &str) -> Result<AnalyticsEngineDataset> {
48        self.get_binding::<AnalyticsEngineDataset>(binding)
49    }
50
51    /// Access Secret value bindings added to your Worker via the UI or `wrangler`:
52    /// <https://developers.cloudflare.com/workers/cli-wrangler/commands#secret>
53    pub fn secret(&self, binding: &str) -> Result<Secret> {
54        self.get_binding::<Secret>(binding)
55    }
56
57    /// Get an environment variable defined in the [vars] section of your wrangler.toml or a secret
58    /// defined using `wrangler secret` as a plaintext value.
59    ///
60    /// See: <https://developers.cloudflare.com/workers/configuration/environment-variables/>
61    pub fn var(&self, binding: &str) -> Result<Var> {
62        self.get_binding::<Var>(binding)
63    }
64
65    /// Get an environment variable defined in the [vars] section of your wrangler.toml that is
66    /// defined as an object.
67    ///
68    /// See: <https://developers.cloudflare.com/workers/configuration/environment-variables/>
69    pub fn object_var<T: DeserializeOwned>(&self, binding: &str) -> Result<T> {
70        Ok(serde_wasm_bindgen::from_value(
71            self.get_binding::<JsValueWrapper>(binding)?.0,
72        )?)
73    }
74
75    /// Access a Workers KV namespace by the binding name configured in your wrangler.toml file.
76    pub fn kv(&self, binding: &str) -> Result<KvStore> {
77        KvStore::from_this(self, binding).map_err(From::from)
78    }
79
80    /// Access a Durable Object namespace by the binding name configured in your wrangler.toml file.
81    pub fn durable_object(&self, binding: &str) -> Result<ObjectNamespace> {
82        self.get_binding(binding)
83    }
84
85    /// Access a Dynamic Dispatcher for dispatching events to other workers.
86    pub fn dynamic_dispatcher(&self, binding: &str) -> Result<DynamicDispatcher> {
87        self.get_binding(binding)
88    }
89
90    /// Get a [Service Binding](https://developers.cloudflare.com/workers/runtime-apis/service-bindings/)
91    /// for Worker-to-Worker communication.
92    pub fn service(&self, binding: &str) -> Result<Fetcher> {
93        self.get_binding(binding)
94    }
95
96    #[cfg(feature = "queue")]
97    /// Access a Queue by the binding name configured in your wrangler.toml file.
98    pub fn queue(&self, binding: &str) -> Result<Queue> {
99        self.get_binding(binding)
100    }
101
102    /// Access an R2 Bucket by the binding name configured in your wrangler.toml file.
103    pub fn bucket(&self, binding: &str) -> Result<Bucket> {
104        self.get_binding(binding)
105    }
106
107    /// Access a D1 Database by the binding name configured in your wrangler.toml file.
108    #[cfg(feature = "d1")]
109    pub fn d1(&self, binding: &str) -> Result<D1Database> {
110        self.get_binding(binding)
111    }
112
113    /// Access the worker assets by the binding name configured in your wrangler.toml file.
114    pub fn assets(&self, binding: &str) -> Result<Fetcher> {
115        self.get_binding(binding)
116    }
117
118    pub fn hyperdrive(&self, binding: &str) -> Result<Hyperdrive> {
119        self.get_binding(binding)
120    }
121
122    /// Access a Secret Store by the binding name configured in your wrangler.toml file.
123    pub fn secret_store(&self, binding: &str) -> Result<SecretStore> {
124        self.get_binding(binding)
125    }
126}
127
128pub trait EnvBinding: Sized + JsCast {
129    const TYPE_NAME: &'static str;
130
131    fn get(val: JsValue) -> Result<Self> {
132        let obj = Object::from(val);
133        if obj.constructor().name() == Self::TYPE_NAME {
134            Ok(obj.unchecked_into())
135        } else {
136            Err(format!(
137                "Binding cannot be cast to the type {} from {}",
138                Self::TYPE_NAME,
139                obj.constructor().name()
140            )
141            .into())
142        }
143    }
144}
145
146#[repr(transparent)]
147#[derive(Debug)]
148pub struct StringBinding(JsValue);
149
150impl EnvBinding for StringBinding {
151    const TYPE_NAME: &'static str = "String";
152}
153
154impl JsCast for StringBinding {
155    fn instanceof(val: &JsValue) -> bool {
156        val.is_string()
157    }
158
159    fn unchecked_from_js(val: JsValue) -> Self {
160        StringBinding(val)
161    }
162
163    fn unchecked_from_js_ref(val: &JsValue) -> &Self {
164        // Safety: Self is marked repr(transparent)
165        unsafe { &*(val as *const JsValue as *const Self) }
166    }
167}
168
169impl AsRef<JsValue> for StringBinding {
170    fn as_ref(&self) -> &wasm_bindgen::JsValue {
171        unsafe { &*(&self.0 as *const JsValue) }
172    }
173}
174
175impl From<JsValue> for StringBinding {
176    fn from(val: JsValue) -> Self {
177        StringBinding(val)
178    }
179}
180
181impl From<StringBinding> for JsValue {
182    fn from(sec: StringBinding) -> Self {
183        sec.0
184    }
185}
186
187impl Display for StringBinding {
188    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::result::Result<(), std::fmt::Error> {
189        write!(f, "{}", self.0.as_string().unwrap_or_default())
190    }
191}
192
193#[repr(transparent)]
194struct JsValueWrapper(JsValue);
195
196impl EnvBinding for JsValueWrapper {
197    const TYPE_NAME: &'static str = "Object";
198}
199
200impl JsCast for JsValueWrapper {
201    fn instanceof(_: &JsValue) -> bool {
202        true
203    }
204
205    fn unchecked_from_js(val: JsValue) -> Self {
206        Self(val)
207    }
208
209    fn unchecked_from_js_ref(val: &JsValue) -> &Self {
210        // Safety: Self is marked repr(transparent)
211        unsafe { &*(val as *const JsValue as *const Self) }
212    }
213}
214
215impl From<JsValueWrapper> for wasm_bindgen::JsValue {
216    fn from(value: JsValueWrapper) -> Self {
217        value.0
218    }
219}
220
221impl AsRef<JsValue> for JsValueWrapper {
222    fn as_ref(&self) -> &JsValue {
223        &self.0
224    }
225}
226
227/// A string value representing a binding to a secret in a Worker.
228#[doc(inline)]
229pub use StringBinding as Secret;
230/// A string value representing a binding to an environment variable in a Worker.
231pub type Var = StringBinding;
worker/env.rs

worker/
env.rs
