Bunch of more thread-safety (I hope)

Author: MrLotU

Sources/Prometheus/MetricTypes/Counter.swift

@@ -45,8 +45,11 @@ public class Counter<NumType: Numeric, Labels: MetricLabels>: Metric, Prometheus
         prometheusQueue.async(flags: .barrier) {
             var output = [String]()
 
-            output.append(self.headers)
-            
+            if let help = self.help {
+                output.append("# HELP \(self.name) \(help)")
+            }
+            output.append("# TYPE \(self.name) \(self._type)")
+
             output.append("\(self.name) \(self.value)")
 
             self.metrics.forEach { (labels, value) in

Sources/Prometheus/MetricTypes/Gauge.swift

@@ -45,8 +45,11 @@ public class Gauge<NumType: Numeric, Labels: MetricLabels>: Metric, PrometheusHa
         prometheusQueue.async(flags: .barrier) {
             var output = [String]()
 
-            output.append(self.headers)
-            
+            if let help = self.help {
+                output.append("# HELP \(self.name) \(help)")
+            }
+            output.append("# TYPE \(self.name) \(self._type)")
+
             output.append("\(self.name) \(self.value)")
 
             self.metrics.forEach { (labels, value) in

Sources/Prometheus/MetricTypes/Histogram.swift

@@ -77,8 +77,11 @@ public class Histogram<NumType: DoubleRepresentable, Labels: HistogramLabels>: M
         prometheusQueue.async(flags: .barrier) {
             var output = [String]()
 
-            output.append(self.headers)
-            
+            if let help = self.help {
+                output.append("# HELP \(self.name) \(help)")
+            }
+            output.append("# TYPE \(self.name) \(self._type)")
+
             var acc: NumType = 0
             for (i, bound) in self.upperBounds.enumerated() {
                 acc += self.buckets[i].get()

Sources/Prometheus/MetricTypes/Info.swift

@@ -45,7 +45,10 @@ public class Info<Labels: MetricLabels>: Metric, PrometheusHandled {
         prometheusQueue.async(flags: .barrier) {
             var output = [String]()
 
-            output.append(self.headers)
+            if let help = self.help {
+                output.append("# HELP \(self.name) \(help)")
+            }
+            output.append("# TYPE \(self.name) \(self._type)")
 
             let labelsString = encodeLabels(self.labels)
             output.append("\(self.name)\(labelsString) 1.0")

Sources/Prometheus/MetricTypes/Metric.swift

@@ -14,17 +14,13 @@ public protocol Metric {
     func getMetric(_ done: @escaping (String) -> Void)
 }
 
-extension Metric {
-    /// Default headers for a metric
-    var headers: String {
-        var output = [String]()
-        if let help = help {
-            output.append("# HELP \(name) \(help)")
-        }
-        output.append("# TYPE \(name) \(_type)")
-        return output.joined(separator: "\n")
-    }
-}
+//extension Metric {
+//    /// Default headers for a metric
+//    var headers: String {
+//        var output = [String]()
+//        return output.joined(separator: "\n")
+//    }
+//}
 
 /// Adding a prometheus instance to all
 /// metrics

Sources/Prometheus/MetricTypes/Summary.swift

@@ -78,8 +78,11 @@ public class Summary<NumType: DoubleRepresentable, Labels: SummaryLabels>: Metri
         prometheusQueue.async(flags: .barrier) {
             var output = [String]()
 
-            output.append(self.headers)
-            
+            if let help = self.help {
+                output.append("# HELP \(self.name) \(help)")
+            }
+            output.append("# TYPE \(self.name) \(self._type)")
+
             calculateQuantiles(quantiles: self.quantiles, values: self.values.map { $0.doubleValue }).sorted { $0.key < $1.key }.forEach { (arg) in
                 let (q, v) = arg
                 self.labels.quantile = "\(q)"

Sources/Prometheus/Prometheus.swift

@@ -14,7 +14,7 @@ public class PrometheusClient {
     ///
     /// - Returns: Newline seperated string with metrics for all Metric Trackers of this Prometheus instance
     public func getMetrics(_ done: @escaping (String) -> Void) {
-//        prometheusQueue.async(flags: .barrier) {
+        prometheusQueue.async(flags: .barrier) {
             var list = [String]()
             self.metrics.forEach { metric in
                 metric.getMetric { str in
@@ -25,7 +25,7 @@ public class PrometheusClient {
                     }
                 }
             }
-//        }
+        }
     }
 
     // MARK: - Counter
@@ -48,7 +48,9 @@ public class PrometheusClient {
         withLabelType labelType: U.Type) -> Counter<T, U>
     {
         let counter = Counter<T, U>(name, helpText, initialValue, self)
-        self.metrics.append(counter)
+        prometheusQueue.async(flags: .barrier) {
+            self.metrics.append(counter)
+        }
         return counter
     }
 
@@ -90,7 +92,9 @@ public class PrometheusClient {
         withLabelType labelType: U.Type) -> Gauge<T, U>
     {
         let gauge = Gauge<T, U>(name, helpText, initialValue, self)
-        self.metrics.append(gauge)
+        prometheusQueue.async(flags: .barrier) {
+            self.metrics.append(gauge)
+        }
         return gauge
     }
 
@@ -132,7 +136,9 @@ public class PrometheusClient {
         labels: U.Type) -> Histogram<T, U>
     {
         let histogram = Histogram<T, U>(name, helpText, U(), buckets, self)
-        self.metrics.append(histogram)
+        prometheusQueue.async(flags: .barrier) {
+            self.metrics.append(histogram)
+        }
         return histogram
     }
 
@@ -174,7 +180,9 @@ public class PrometheusClient {
         labels: U.Type) -> Summary<T, U>
     {
         let summary = Summary<T, U>(name, helpText, U(), quantiles, self)
-        metrics.append(summary)
+        prometheusQueue.async(flags: .barrier) {
+            self.metrics.append(summary)
+        }
         return summary
     }
 
@@ -212,7 +220,9 @@ public class PrometheusClient {
         labelType: U.Type) -> Info<U>
     {
         let info = Info<U>(name, helpText, self)
-        self.metrics.append(info)
+        prometheusQueue.async(flags: .barrier) {
+            self.metrics.append(info)
+        }
         return info
     }
 }