Upgrade to prometheus 0.13 (#21)

* Update dependencies
* Fix clippy lint
* Bump version
* Update readme

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "prometheus_exporter"
-version = "0.8.2"
+version = "0.8.3"
 authors = ["Alexander Thaller <alexander.thaller@trivago.com>"]
 
 description = "Helper libary to export prometheus metrics using tiny-http."
@@ -27,12 +27,12 @@ internal_metrics = ["lazy_static"]
 ascii = "1"
 lazy_static = { version = "1", optional = true }
 log = { version = "0.4", optional = true }
-prometheus = { version = "0.12", default-features = false }
+prometheus = { version = "0.13", default-features = false }
 thiserror = "1"
-tiny_http = { version = "0.8", default-features = false }
+tiny_http = { version = "0.9", default-features = false }
 
 [dev-dependencies]
-env_logger = "0.8"
+env_logger = "0.9"
 log = { version = "0.4" }
 rand = "0.8"
 reqwest = { version = "0.11", features = ["blocking"] }

README.md

@@ -17,10 +17,13 @@ collecting and rendering the prometheus metrics and
 through http.
 
 **NOTICE:** You have to use the same prometheus crate version that is used by
-this crate to make sure that the global registrar use by the prometheus macros
-works as expected. This crate re-exports the prometheus crate to make it easier
-to keep versions in sync (see examples). Currently this crate uses prometheus
-version `0.11`.
+this crate. This crate currently uses the metrics stored in the global registry.
+A different prometheus crate will register to a different global registry. This
+means that the macros used to register new metrics do not expose metrics to this
+exporter.
+
+This crate re-exports the prometheus crate to make it easier to keep versions in
+sync (see examples). Currently this crate uses prometheus version `0.13`.
 
 For information on how to migrate from an older crate version follow
 [MIGRATION](/MIGRATION.md).

src/lib.rs

@@ -394,7 +394,7 @@ impl Server {
 
                     // Just so there are no complains about unused err variable when logging
                     // feature is disabled
-                    drop(err)
+                    drop(err);
                 }
             }
         });