Mapping the dimensions

README.md

@@ -285,6 +285,80 @@ interval="10s"
 [[inputs.kernel]]
 ```
 
+#### TransformSource
+Sometimes you'll want to transform the incoming data before aggregating.
+As shown in the example collectd source, it is possible to wrap a source with
+another source that will transform the data.  The TransformingSource specifies
+sets of transformations to apply to the input records, allowing you to add dimensions
+to all metrics, remove dimensions from all metrics, and modify metrics based on their
+name.
+
+ex:
+```hocon
+{
+  type="com.arpnetworking.metrics.mad.sources.TransformingSource"
+  name="transforming_source"
+  transformations = [
+    {
+      injectDimensions = {
+        foo {
+          value = bar
+          overwrite = false
+        }
+      }
+      removeDimensions = [
+        baz
+      ]
+      transformMetrics = {
+        "this" = ["that"]
+        "extract/([^/]*)/thing" = ["extract/thing/${other_dimension};my_dimension=${1}"]
+      }
+    }
+  ]
+  source {
+    // your wrapped source goes here
+  }
+}
+```
+
+tranformations is a list of TransformationSet objects.  Each TransformationSet has an inject (Map\<String, DimensionInjection\>),
+ remove (List\<String\>) and a findAndReplace (Map\<String, List\<String\>\>).
+
+ A DimensionInjection is just a value and a boolean of whether or not to overwrite existing values. Of omitted, overwrite defaults to true.
+
+ The keys in findAndReplace are regular expressions used to match metrics.  If matched, the list of replacements is
+ executed, allowing for a single input metric to be recorded multiple times with different names or dimensions.
+ The format for the values in the list are similar to a standard java regex replacement.  Variables are enclosed in ${},
+ for example:
+ ```bash
+${my_variable}
+```
+Variables will be matched in the following order (first match wins):
+1. capture group
+2. dimension
+3. environment variable
+
+
+Variable names may also have a prefix that specifies where the value should originate.  For example:
+```bash
+${capture:my_var}
+```
+```bash
+${env:MYVAR}
+```
+```bash
+${dimension:some_dimension}
+```
+
+This namespacing prevents the built-in precendence search for a matching variable.
+
+__Note: Any dimensions matched as part of a replacement will be removed from the resulting metric.__
+
+Dimensions can also be injected into a metric.  To do this, add a ';' after the replacement name of the metric
+and proceed to specify key=value pairs (where both the key and value can use variables).  Basically, the
+replacement is processed, the string split on ';' with the first part being the metric name and anything
+after the ';' being parsed as key=value pairs to be added to the metric's dimensions.
+
 Development
 -----------
 

jdk-wrapper.sh

@@ -40,6 +40,27 @@ safe_command() {
   fi
 }
 
+checksum() {
+  l_file="$1"
+  checksum_exec=""
+  if command -v md5 > /dev/null; then
+    checksum_exec="md5"
+  elif command -v sha1sum > /dev/null; then
+    checksum_exec="sha1sum"
+  elif command -v shasum > /dev/null; then
+    checksum_exec="shasum"
+  fi
+  if [ -z "${checksum_exec}" ]; then
+    log_err "ERROR: No supported checksum command found!"
+    exit 1
+  fi
+  cat "${l_file}" | ${checksum_exec}
+}
+
+rand() {
+  awk 'BEGIN {srand();printf "%d\n", (rand() * 10^8);}'
+}
+
 download() {
   file="$1"
   if [ ! -f "${JDKW_PATH}/${file}" ]; then
@@ -93,7 +114,10 @@ fi
 
 # Resolve latest version
 if [ "${JDKW_RELEASE}" = "latest" ]; then
-  JDKW_RELEASE=$(curl ${CURL_OPTIONS} -f -k -L -H 'Accept: application/json' "${JDKW_BASE_URI}/releases/latest" | sed -e 's/.*"tag_name":"\([^"]*\)".*/\1/')
+  latest_version_json="${TMPDIR:-/tmp}/jdkw-latest-version-$$.$(rand)"
+  safe_command "curl ${CURL_OPTIONS} -f -k -L -o \"${latest_version_json}\" -H 'Accept: application/json' \"${JDKW_BASE_URI}/releases/latest\""
+  JDKW_RELEASE=$(cat "${latest_version_json}" | sed -e 's/.*"tag_name":"\([^"]*\)".*/\1/')
+  rm -f "${latest_version_json}"
   log_out "Resolved latest version to ${JDKW_RELEASE}"
 fi
 
@@ -114,7 +138,7 @@ download "${JDKW_WRAPPER}"
 # Check whether this wrapper is the one specified for this version
 jdkw_download="${JDKW_PATH}/${JDKW_WRAPPER}"
 jdkw_current="$(CDPATH= cd -- "$(dirname -- "$0")" && pwd)/$(basename "$0")"
-if [ "$(cat "${jdkw_download}" | sha1sum )" != "$(cat "${jdkw_current}" | sha1sum)" ]; then
+if [ "$(checksum "${jdkw_download}")" != "$(checksum "${jdkw_current}")" ]; then
   printf "\e[0;31m[WARNING]\e[0m Your jdk-wrapper.sh file does not match the one in your JDKW_RELEASE.\n"
   printf "\e[0;32mUpdate your jdk-wrapper.sh to match by running:\e[0m\n"
   printf "cp \"%s\" \"%s\"\n" "${jdkw_download}" "${jdkw_current}"