New applications aren't allowed to send token in query parameters any more

[Fuuzetsu]

https://api.slack.com/changelog/2020-11-no-more-tokens-in-querystrings-for-newly-created-apps

Indeed, I can use the same token to send a message if I put the token in the header but this crate wants to put it in the query itself.

This gives a confusing invalid_auth message.

[Fuuzetsu]

Below is a dirty hack that rips out token and puts it in header. You can't keep it in the params even if you have the header present.

/// Work-around for <https://github.com/slack-rs/slack-rs-api/issues/107>.
struct AuthClient {
    inner: Client,
}

impl AuthClient {
    pub fn new() -> Result<Self, reqwest::Error> {
        Ok(Self {
            inner: slack_api::default_client()?,
        })
    }
}

#[async_trait::async_trait]
impl SlackWebRequestSender for AuthClient {
    type Error = <Client as SlackWebRequestSender>::Error;

    async fn send<I, K, V, S>(&self, method: S, params: I) -> Result<String, Self::Error>
    where
        I: IntoIterator + Send,
        K: AsRef<str>,
        V: AsRef<str>,
        I::Item: std::borrow::Borrow<(K, V)>,
        S: AsRef<str> + Send,
    {
        let mut url = reqwest::Url::parse(method.as_ref()).expect("Unable to parse url");

        let mut token = None;
        {
            let mut qp = url.query_pairs_mut();
            for param in params {
                let (k, v) = param.borrow();
                if k.as_ref() == "token" {
                    token = Some(v.as_ref().to_owned());
                    continue;
                }
                qp.append_pair(k.as_ref(), v.as_ref());
            }
        }

        let mut req = self.inner.get(url);
        if let Some(token) = token {
            req = req.bearer_auth(token);
        };

        Ok(req.send().await?.text().await?)
    }
}