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/*!
# Firebase REST API for Rust
Please have a look at the ```Firebase``` struct to get started.
*/
extern crate knock;
extern crate url;
extern crate curl;
use knock::HTTP;
use knock::Data;
use std::str;
use std::borrow::Cow;
use std::collections::HashMap;
use std::sync::Arc;
use std::thread;
use std::time::Duration;
use std::thread::JoinHandle;
use url::Url;
/// A Firebase instance to manage data.
#[derive(Clone)]
pub struct Firebase {
url: Arc<Url>,
}
// TODO: Change all instances of &str to Into<String>
// TODO: Make FB instance from Url and String.
// TODO: Make closure lives 'static or 'fb ?
impl Firebase {
/// Creates a new Firebase instance from the url of the fb server
/// The url should be a valid **HTTPS** url, anything else will
/// result in an error:
///
/// https://docs-examples.firebaseio.com/
///
/// # Failures
/// - If a url is not specified with the HTTPS scheme, a ```Err(ParseError::UrlIsNotHTTPS)```
/// will be returned.
/// - If a url cannot be parsed into a valid url then a ```Err(ParseError::Parser(url::ParseError)```
/// will be returned.
pub fn new(url: &str) -> Result<Self, ParseError> {
let url = try!(parse(&url));
if url.scheme() != "https" {
return Err(ParseError::UrlIsNotHTTPS);
}
try!(unwrap_path(&url));
Ok(Firebase {
url: Arc::new(url),
})
}
/// Creates a firebase reference from a borrow of a Url instance.
/// # Failures
/// - If a url is not specified with the HTTPS scheme, a ```Err(ParseError::UrlIsNotHTTPS)```
/// will be returned.
/// - If a url cannot be parsed into a valid url then a ```Err(ParseError::Parser(url::ParseError)```
/// will be returned.
pub fn from_url(url: &Url) -> Result<Self, ParseError> {
let url = url.clone();
try!(unwrap_path(&url));
Ok(Firebase {
url: Arc::new(url),
})
}
/// Creates a new authenticated Firebase instance from the firebaseio url and an auth token.
///
/// # Examples
/// ```
/// # use firebase::Firebase;
/// let fb = Firebase::authed("https://myfb.firebaseio.com", "deadbeefcafe");
/// // The url shoud now be: https://myfb.firebaseio.com?auth=deadbeefcafe
/// ```
///
/// # Failures
/// - If a url is not specified with the HTTPS scheme, a ```Err(ParseError::UrlIsNotHTTPS)```
/// will be returned.
/// - If a url cannot be parsed into a valid url then a ```Err(ParseError::Parser(url::ParseError)```
/// will be returned.
pub fn authed(url: &str, auth_token: &str) -> Result<Self, ParseError> {
let mut url = try!(parse(&url));
if url.scheme() != "https" {
return Err(ParseError::UrlIsNotHTTPS);
}
try!(unwrap_path(&url));
let opts = vec![(AUTH, auth_token)];
url.set_query(Some(&format!("{}{}{}", AUTH.to_owned(), "=", auth_token.to_owned())[..]));
Ok(Firebase {
url: Arc::new(url),
})
}
/// Creates a new firebase instance that extends the path of an old firebase instance.
/// Each time a reference is created a clone of the Firebase instance if done, all
/// Firebase instances follow this immutable style.
///
/// #Examples
/// ```
/// # use firebase::Firebase;
/// // Points to the root of the db ( / )
/// let fb = Firebase::new("https://myfb.firebaseio.com").unwrap();
/// // A new reference to /friends/yasha
/// let yasha = fb.at("/friends/yasha").unwrap();
/// // A new reference to /friends/yasha/messages
/// let messages = yasha.at("messages").unwrap();
pub fn at(&self, add_path: &str) -> Result<Self, ParseError> {
let mut url = (*self.url).clone();
{ // Add path to original path, already checked for path.
let mut path = url.path().to_owned();
// Remove .json from the old path's end.
// Todo check this if let Some(end) = path.pop() {
// path.push_str(end.trim_right_matches(".json").to_string());
// }
let add_path = add_path.trim_matches('/');
let add_path = if !add_path.ends_with(".json") {
Cow::Owned(add_path.to_string() + ".json")
} else {
Cow::Borrowed(add_path)
};
for component in add_path.split("/") {
path.push_str(component);
}
}
Ok(Firebase {
url: Arc::new(url),
})
}
/// Creates a FirebaseParams instance, this instance has query parameters
/// that are associated with it and that are used in every request made.
/// Since query parameters only affect incomming data from Firebase, you can only
/// GET data with a FirebaseParams instance.
///
/// This constructor takes in a FbOps struct to define all of its parameters,
/// all undefined parameters can be omitted by extending the new FbOps struct
/// by its default.
///
/// # Examples
/// ```
/// # use firebase::*;
/// let fb = Firebase::new("https://db.fb.com").unwrap();
/// let query = fb.ops(&FbOps {
/// order_by: Some("Hello World"),
/// limit_to_first: Some(5),
/// end_at: Some(7),
/// equal_to: Some(3),
/// shallow: Some(true),
/// format: Some(true),
/// .. FbOps::default()
/// });
/// ```
pub fn ops(&self, opts: &FbOps) -> FirebaseParams {
FirebaseParams::from_ops(&self.url, opts)
}
/// Returns the current URL as a string that will be used
/// to make the REST call when talking to Firebase.
pub fn get_url(&self) -> String {
self.url.as_str().to_owned()
}
/// Gets data from Firebase.
/// # Examples
/// ```
/// # use firebase::Firebase;
/// let firebase = Firebase::new("https://shows.firebaseio.com").unwrap();
/// let episode = firebase.at("/futurama/episodes/140").unwrap();
/// let info = episode.get();
/// ```
pub fn get(&self) -> Result<Response, i64> {
self.request(Method::GET, None)
}
/// Sets data to Firebase.
/// # Examples
/// ```
/// # use firebase::Firebase;
/// let firebase = Firebase::new("https://shows.firebaseio.com").unwrap();
/// let episode = firebase.at("/futurama/episodes/140/description").unwrap();
/// let info = episode.set("The Last Episode!");
/// ```
pub fn set(&self, data: HashMap<String, Data>) -> Result<Response, i64> {
self.request(Method::PUT, Some(data))
}
/// Pushes data to Firebase.
/// # Examples
/// ```
/// # use firebase::Firebase;
/// let firebase = Firebase::new("https://shows.firebaseio.com").unwrap();
/// let episodes = firebase.at("/futurama/episodes").unwrap();
/// let info = episodes.push("The Lost Episode");
/// ```
pub fn push(&self, data: HashMap<String, Data>) -> Result<Response, i64> {
self.request(Method::POST, Some(data))
}
/// Updates Firebase data.
/// # Examples
/// ```
/// # use firebase::Firebase;
/// let firebase = Firebase::new("https://shows.firebaseio.com").unwrap();
/// let desc = firebase.at("/futurama/episodes/140/description").unwrap();
/// let info = desc.update("The Penultimate Episode!");
/// ```
pub fn update(&self, data: HashMap<String, Data>) -> Result<Response, i64> {
self.request(Method::PATCH, Some(data))
}
/// Removes Firebase data.
/// # Examples
/// ```
/// # use firebase::Firebase;
/// let firebase = Firebase::new("https://shows.firebaseio.com").unwrap();
/// let episode = firebase.at("/futurama/episodes/141").unwrap();
/// episode.remove();
/// ```
pub fn remove(&self) -> Result<Response, i64> {
self.request(Method::DELETE, None)
}
/// Asynchronous version of the get method, takes a callback
/// and returns a handle to the thread making the request to Firebase.
/// # Examples
/// ```
/// # use firebase::Firebase;
/// let firebase = Firebase::new("https://shows.firebaseio.com").unwrap();
/// let desc = firebase.at("/futurama/episodes/141/description").unwrap();
/// let original = "The Lost Episode";
/// desc.get_async(move |result| {
/// if result.unwrap().body != original {
/// println!("The description changed!");
/// }
/// });
pub fn get_async<F>(&self, callback: F) -> JoinHandle<()>
where F: Fn(Result<Response, i64>) + Send + 'static {
Firebase::request_url_async(&self.url, Method::GET, HashMap::new(), callback)
}
/// Asynchronous version of the set method, takes a callback
/// and returns a handle to the thread making the request to Firebase.
pub fn set_async<S, F>(&self, data: HashMap<String, Data>, callback: F) -> JoinHandle<()>
where F: Fn(Result<Response, i64>) + Send + 'static, S: Into<String> {
Firebase::request_url_async(&self.url, Method::PUT, data, callback)
}
/// Asynchronous version of the push method, takes a callback
/// and returns a handle to the thread making the request to Firebase.
pub fn push_async<S, F>(&self, data: HashMap<String, Data>, callback: F) -> JoinHandle<()>
where F: Fn(Result<Response, i64>) + Send + 'static {
Firebase::request_url_async(&self.url, Method::POST, data, callback)
}
/// Asynchronous version of the update method, takes a callback
/// and returns a handle to the thread making the request to Firebase.
pub fn update_async<S, F>(&self, data: HashMap<String, Data>, callback: F) -> JoinHandle<()>
where F: Fn(Result<Response, i64>) + Send + 'static {
Firebase::request_url_async(&self.url, Method::PATCH, data, callback)
}
/// Asynchronous version of the remove method, takes a callback
/// and returns a handle to the thread making the request to Firebase.
/// Todo remove all the empty hashes
pub fn remove_async<F>(&self, callback: F) -> JoinHandle<()>
where F: Fn(Result<Response, i64>) + Send + 'static {
Firebase::request_url_async(&self.url, Method::DELETE, HashMap::new(), callback)
}
/// Creates a ```FirebaseParams``` instance, a Firebase struct that only
/// knows how to GET data, and sorts this data by the key provided.
pub fn order_by(&self, key: &str) -> FirebaseParams {
self.with_params(ORDER_BY, key)
}
/// Creates a ```FirebaseParams``` instance, a Firebase struct that only
/// knows how to GET data, and limits the number of entries returned
/// on each request to the first ```count```. Often used with ```order_by```.
pub fn limit_to_first(&self, count: u32) -> FirebaseParams {
self.with_params(LIMIT_TO_FIRST, count)
}
/// Creates a ```FirebaseParams``` instance, a Firebase struct that only
/// knows how to GET data, and limits the number of entries returned
/// on each request to the last ```count```. Often used with ```order_by```.
pub fn limit_to_last(&self, count: u32) -> FirebaseParams {
self.with_params(LIMIT_TO_LAST, count)
}
/// Creates a ```FirebaseParams``` instance, a Firebase struct that only
/// knows how to GET data, and only returns entries starting after
/// the specified index. Often used with ```order_by```.
pub fn start_at(&self, index: u32) -> FirebaseParams {
self.with_params(START_AT, index)
}
/// Creates a ```FirebaseParams``` instance, a Firebase struct that only
/// knows how to GET data, and only returns entries appearing before
/// the specified index. Often used with ```order_by```.
pub fn end_at(&self, index: u32) -> FirebaseParams {
self.with_params(END_AT, index)
}
/// Creates a ```FirebaseParams``` instance, a Firebase struct that only
/// knows how to GET data, and returns only the entry at the specified
/// index. Often used with ```order_by```.
pub fn equal_to(&self, index: u32) -> FirebaseParams {
self.with_params(EQUAL_TO, index)
}
/// Creates a ```FirebaseParams``` instance, a Firebase struct that only
/// knows how to GET data, and only returns a shallow copy of the db
/// in every request.
pub fn shallow(&self, flag: bool) -> FirebaseParams {
self.with_params(SHALLOW, flag)
}
/// Creates a ```FirebaseParams``` instance, a Firebase struct that only
/// knows how to GET data, and formats the data to be exported in every
/// request. (e.g. includes a priority field).
pub fn format(&self) -> FirebaseParams {
self.with_params(FORMAT, EXPORT)
}
#[inline]
fn request(&self, method: Method, data: Option<HashMap<String, Data>>) -> Result<Response, i64> {
Firebase::request_url(&self.url, method, data.unwrap())
}
fn request_url(url: &Url, method: Method, data: HashMap<String, Data>) -> Result<Response, i64> {
let mut http = HTTP::new(url.as_str()).unwrap();
let response = match method {
Method::GET => http.get().send(),
Method::POST => http.post().body(data).send(),
Method::PUT => http.put().body(data).send(),
// TODO add patch method
Method::DELETE => http.delete().body(data).send(),
_ => http.post().body(data).send(),
};
//Todo fix status codes
let res: Response = Response { body: response.unwrap().as_str().to_owned(), code: 200i64 };
// Ok(res);
//Todo fix
Err(-1)
}
fn request_url_async<F>(url: &Arc<Url>, method: Method, data: HashMap<String, Data>, callback: F) -> JoinHandle<()>
where F: Fn(Result<Response, i64>) + Send + 'static {
// Fast, because its in an arc.
let url = url.clone();
thread::spawn(move || {
callback(Firebase::request_url(&url, method, data));
})
}
fn with_params<T: ToString>(&self, key: &'static str, value: T) -> FirebaseParams {
FirebaseParams::new(&self.url, key, value)
}
}
/// The FirebaseParams struct is a Firebase reference with attatched
/// query parameters that allow you to sort, limit, and format the data
/// received from Firebase.
///
/// It has been made into its own struct because the Firebase API specifies
/// that you can only GET data with query parameters. And so taking advantage of
/// type systems, this struct can only GET data.
///
/// You can add any number of parameters to this struct by chaining calls together:
///
/// ```
/// # use firebase::*;
/// let episodes = Firebase::new("https://futurama.firebaseio.com/episodes/").unwrap();
/// let alphabetic = episodes.order_by("\"title\"").limit_to_first(5);
/// let first5 = alphabetic.get();
/// ```
///
/// Setting the same parameter overwrites the previous parameter:
///
/// ```
/// # use firebase::*;
/// let episodes = Firebase::new("https://arrdev.firebaseio.com/episodes/").unwrap();
/// // This will create a request that gets entries starting at the 0th index.
/// let skip10 = episodes.start_at(10).start_at(0);
/// ```
#[derive(Clone)]
pub struct FirebaseParams {
url: Arc<Url>,
params: HashMap<&'static str, String>,
}
impl FirebaseParams {
/// Gets data from Firebase.
/// # Examples
/// ```
/// # use firebase::Firebase;
/// let episodes = Firebase::new("https://futurama.firebaseio.com/episodes/").unwrap();
/// let alphabetic = episodes.order_by("\"title\"").limit_to_first(5);
/// let first5 = alphabetic.get();
/// ```
pub fn get(&self) -> Result<Response, i64> {
//Todo remove empty hash
Firebase::request_url(&self.url, Method::GET, HashMap::new())
}
/// Asynchronous version of the get method, takes a callback
/// and returns a handle to the thread making the request to Firebase.
pub fn get_async<F>(&self, callback: F) -> JoinHandle<()>
where F: Fn(Result<Response, i64>) + Send + 'static {
//Todo remove empty hash
Firebase::request_url_async(&self.url, Method::GET, HashMap::new(), callback)
}
/// Returns the current URL as a string that will be used
/// to make the REST call when talking to Firebase.
pub fn get_url(&self) -> String {
self.url.as_str().to_owned()
}
// TODO: Wrap in quotes if not already. Or always wrap in quotes.
/// Modifies the current ```FirebaseParams``` instance
/// and sorts this data by the key provided.
pub fn order_by(self, key: &str) -> Self {
self.add_param(ORDER_BY, key)
}
/// Modifies the current ```FirebaseParams``` instance
/// and limits the number of entries returned
/// on each request to the first ```count```. Often used with ```order_by```.
pub fn limit_to_first(self, count: u32) -> Self {
self.add_param(LIMIT_TO_FIRST, count)
}
/// Modifies the current ```FirebaseParams``` instance
/// and limits the number of entries returned
/// on each request to the last ```count```. Often used with ```order_by```.
pub fn limit_to_last(self, count: u32) -> Self {
self.add_param(LIMIT_TO_LAST, count)
}
/// Modifies the current ```FirebaseParams``` instance
/// and only returns entries starting after
/// the specified index. Often used with ```order_by```.
pub fn start_at(self, index: u32) -> Self {
self.add_param(START_AT, index)
}
/// Modifies the current ```FirebaseParams``` instance
/// and only returns entries appearing before
/// the specified index. Often used with ```order_by```.
pub fn end_at(self, index: u32) -> Self {
self.add_param(END_AT, index)
}
/// Modifies the current ```FirebaseParams``` instance
/// and returns only the entry at the specified
/// index. Often used with ```order_by```.
pub fn equal_to(self, value: u32) -> Self {
self.add_param(EQUAL_TO, value)
}
/// Modifies the current ```FirebaseParams``` instance
/// and only returns a shallow copy of the db
/// in every request.
pub fn shallow(self, flag: bool) -> Self {
self.add_param(SHALLOW, flag)
}
/// Modifies the current ```FirebaseParams``` instance
/// and formats the data to be exported in every
/// request. (e.g. includes a priority field)
pub fn format(self) -> Self {
self.add_param(FORMAT, EXPORT)
}
fn add_param<T: ToString>(mut self, key: &'static str, value: T) -> Self {
let value = value.to_string();
self.params.insert(key, value);
self.set_params();
self
}
fn set_params(&mut self) {
// Only clones the url when edited. This is CoW
// Many threads can run requests without ever cloning the url.
let mut url = (*self.url).clone();
//Todo check this one
// url.map(|(&k, v)| (k, v as &str));
self.url = Arc::new(url);
}
fn get_auth(url: &Url) -> HashMap<&'static str, String> {
let mut pair: HashMap<&'static str, String> = HashMap::new();
println!("get auth");
for (ref k, ref v) in url.query_pairs().enumerate().into_iter() {
// if k == AUTH {
// pair.insert(AUTH, v.to_owned());
// }
println!("{:?}", v);
}
pair
}
fn new<T: ToString>(url: &Url, key: &'static str, value: T) -> Self {
let me = FirebaseParams {
url: Arc::new(url.clone()),
params: FirebaseParams::get_auth(&url),
};
me.add_param(key, value)
}
fn from_ops(url: &Url, opts: &FbOps) -> Self {
let mut me = FirebaseParams {
url: Arc::new(url.clone()),
params: FirebaseParams::get_auth(&url),
};
if let Some(order) = opts.order_by {
me.params.insert(ORDER_BY, order.to_string());
}
if let Some(first) = opts.limit_to_first {
me.params.insert(LIMIT_TO_FIRST, first.to_string());
}
if let Some(last) = opts.limit_to_last {
me.params.insert(LIMIT_TO_LAST, last.to_string());
}
if let Some(start) = opts.start_at {
me.params.insert(START_AT, start.to_string());
}
if let Some(end) = opts.end_at {
me.params.insert(END_AT, end.to_string());
}
if let Some(equal) = opts.equal_to {
me.params.insert(EQUAL_TO, equal.to_string());
}
if let Some(shallow) = opts.shallow {
me.params.insert(SHALLOW, shallow.to_string());
}
if let Some(format) = opts.format {
if format {
me.params.insert(FORMAT, EXPORT.to_string());
}
}
// Copy all of the params into the url.
me.set_params();
me
}
}
enum Method {
GET,
POST,
PUT,
PATCH,
DELETE,
}
const ORDER_BY: &'static str = "orderBy";
const LIMIT_TO_FIRST: &'static str = "limitToFirst";
const LIMIT_TO_LAST: &'static str = "limitToLast";
const START_AT: &'static str = "startAt";
const END_AT: &'static str = "endAt";
const EQUAL_TO: &'static str = "equalTo";
const SHALLOW: &'static str = "shallow";
const FORMAT: &'static str = "format";
const EXPORT: &'static str = "export";
const AUTH: &'static str = "auth";
#[derive(Debug)]
pub struct FbOps<'l> {
pub order_by: Option<&'l str>,
pub limit_to_first: Option<u32>,
pub limit_to_last: Option<u32>,
pub start_at: Option<u32>,
pub end_at: Option<u32>,
pub equal_to: Option<u32>,
pub shallow: Option<bool>,
pub format: Option<bool>,
}
impl<'l> Default for FbOps<'l> {
fn default() -> Self {
FbOps {
order_by: None,
limit_to_first: None,
limit_to_last: None,
start_at: None,
end_at: None,
equal_to: None,
shallow: None,
format: None,
}
}
}
#[derive(Debug)]
pub enum ParseError {
UrlHasNoPath,
UrlIsNotHTTPS,
Parser(url::ParseError),
}
#[derive(Debug)]
pub struct Response {
pub body: String,
pub code: i64,
}
impl Response {
/// Returns true if the status code is 200
pub fn is_success(&self) -> bool {
*(&self.code) == 200
}
/// Returns the body as a string Json enum.
pub fn body(&self) -> &String {
(&self.body)
}
}
fn parse(url: &str) -> Result<Url, ParseError> {
match Url::parse(&url) {
Ok(u) => Ok(u),
Err(e) => Err(ParseError::Parser(e)),
}
}
fn unwrap_path(url: &Url) -> Result<[String; 1], ParseError> {
// match url.path().to_owned() {
// None => return Err(Box::new(ParseError::UrlHasNoPath)),
// Some(p) => return Ok(Box::new(p)),
// }
Ok([url.path().to_owned()])
}
// This code will happen when Trait Specialization becomes available
// in rust.
// pub trait ToJsonStr {
// fn to_json_str(&self) -> Result<Cow<str>, /* TODO */ Box<Error>>;
// }
//
// impl<'l> ToJsonStr for &'l str {
// fn to_json_str(&self) -> Result<Cow<str>, /* TODO */ Box<Error>> {
// Ok(Cow::Borrowed(self))
// }
// }
//
// impl<S> ToJsonStr for S where S: Encodable {
// fn to_json_str(&self) -> Result<Cow<str>, /* TODO */ Box<Error>> {
// match json::encode(self) {
// Ok(encoded) => Ok(Cow::Owned(encoded)),
// Err(e) => Err(Box::new(e)),
// }
// }
// }