Add support Grafana Agent v0.29.0 (#184)

* Add 0.29.0 to downloader

* Set port options as config or flags depending on agent version

Author: Pat Maddox

lib/prom_ex/config.ex

@@ -151,7 +151,7 @@ defmodule PromEx.Config do
       any malicious binaries and running them). By default, PromEx will use the result of
       `PromEx.GrafanaAgent.Downloader.default_version()` if no value is provided.
 
-      * Supported versions are `["0.23.0", "0.22.0", "0.21.2", "0.20.1"]`
+      * Supported versions are `["0.29.0", "0.23.0", "0.22.0", "0.21.2", "0.20.1"]`
 
     * `:working_directory` - In order to leverage the GrafanaAgent functionality, PromEx needs to have
       read/write access to a directory in order to download and copy the GrafanaAgent binary. This is the

lib/prom_ex/grafana_agent.ex

@@ -70,15 +70,37 @@ defmodule PromEx.GrafanaAgent do
     {:noreply, state}
   end
 
-  defp start_agent(%{port_wrapper_path: port_wrapper_path, binary_path: binary_path, config_file_path: config_file_path}) do
+  defp start_agent(
+         %{
+           port_wrapper_path: port_wrapper_path,
+           binary_path: binary_path,
+           config_file_path: config_file_path,
+           grafana_agent_config: %{
+             config_opts: %{
+               agent_port: agent_port,
+               grpc_port: grpc_port
+             }
+           }
+         } = state
+       ) do
     Logger.info("Starting GrafanaAgent")
 
+    wrapper_args = [binary_path, "-config.file", config_file_path]
+
+    wrapper_args =
+      if pre_v0_26?(state) do
+        wrapper_args
+      else
+        wrapper_args ++
+          ["-server.http.address", "127.0.0.1:#{agent_port}", "-server.grpc.address", "127.0.0.1:#{grpc_port}"]
+      end
+
     {:spawn_executable, port_wrapper_path}
     |> Port.open([
       :binary,
       :exit_status,
       :stderr_to_stdout,
-      args: [binary_path, "-config.file", config_file_path]
+      args: wrapper_args
     ])
   end
 
@@ -146,6 +168,7 @@ defmodule PromEx.GrafanaAgent do
     |> Map.get(:grafana_agent_config)
     |> Map.get(:config_opts)
     |> Map.put(:wal_dir, wal_dir)
+    |> Map.put(:render_listen_port, pre_v0_26?(state))
     |> maybe_put_job(state)
     |> maybe_put_instance()
     |> ConfigRenderer.generate_config_file(config_dir)
@@ -169,4 +192,6 @@ defmodule PromEx.GrafanaAgent do
   defp maybe_put_instance(opts) do
     opts
   end
+
+  defp pre_v0_26?(%{grafana_agent_config: %{version: version}}), do: Version.compare(version, "0.26.0") == :lt
 end

lib/prom_ex/grafana_agent/downloader.ex

@@ -7,6 +7,13 @@ defmodule PromEx.GrafanaAgent.Downloader do
     latest_version: "0.23.0",
     github_repo: "grafana/agent",
     download_versions: %{
+      "0.29.0" => [
+        {:darwin, :amd64, "2b51aab7cfa4daf9b18c857c85dddb9ee9086e7470c3585be661fd6577e15afe"},
+        {:darwin, :arm64, "4bf44f44a1e9f4e9c257bea8bcf63549bf4f8f575f8afca94ff0cac371f55ed9"},
+        {:linux, :amd64, "aa07cc24de9d607e6388ce85eec76b250f6a4f304ba86ec7e38fc351d9a2739a"},
+        {:linux, :arm64, "7d402893564e4054d7e1401d10031b9c2841832a2dab5212184f2b606cd08b0d"},
+        {:freebsd, :amd64, "28becd3451ae8d56f4976e87a622da7cd11ce8a02d9bd9f1ee6517785c7fd594"}
+      ],
       "0.23.0" => [
         {:darwin, :amd64, "643044b35ed4bdfd9866a43b70e39d64f16709f9685b89a03b299da8834661b0"},
         {:darwin, :arm64, "e94f7fd0e1ef9fb497cff4f1260cc22967d6a5b003dd2c99f494f9e457482dda"},

priv/grafana_agent/default_config.yml.eex

@@ -1,7 +1,7 @@
 server:
+  log_level: <%= @log_level %><%= if @render_listen_port do %>
   http_listen_port: <%= @agent_port %>
-  grpc_listen_port: <%= @grpc_port %>
-  log_level: <%= @log_level %>
+  grpc_listen_port: <%= @grpc_port %><% end %>
 
 prometheus:
   wal_directory: "<%= @wal_dir %>"
@@ -17,7 +17,7 @@ prometheus:
           static_configs:
             - targets: ["<%= @metrics_server_host %>:<%= @metrics_server_port %>"]
           metric_relabel_configs:
-            - source_labels: [ instance ]
+            - source_labels: [instance]
               target_label: instance
               action: replace
               replacement: "<%= @instance %>"

test/prom_ex/grafana_agent/config_renderer_test.exs

@@ -9,6 +9,7 @@ defmodule PromEx.GrafanaAgent.ConfigRendererTest do
       template_args = %{
         agent_port: "12345",
         grpc_port: "54321",
+        render_listen_port: true,
         log_level: "error",
         wal_dir: "/tmp/test/wal",
         scrape_interval: "5s",
@@ -47,5 +48,33 @@ defmodule PromEx.GrafanaAgent.ConfigRendererTest do
       assert File.exists?(expected_file_path)
       assert File.read!(expected_file_path) == "foo: this is a foo"
     end
+
+    @tag :tmp_dir
+    test "should omnit agent_port and grpc_port from >= v0.26.0", %{tmp_dir: tmp_dir} do
+      template_args = %{
+        agent_port: "12345",
+        grpc_port: "54321",
+        render_listen_port: false,
+        log_level: "error",
+        wal_dir: "/tmp/test/wal",
+        scrape_interval: "5s",
+        job: "TestApp",
+        metrics_server_path: "/cool-metrics",
+        metrics_server_scheme: :https,
+        metrics_server_host: "localhost",
+        bearer_token: "super_secret",
+        metrics_server_port: "1234",
+        instance: "localhost",
+        prometheus_url: "www.my-prometheus.com",
+        prometheus_username: "prom_user",
+        prometheus_password: "prom_pass"
+      }
+
+      ConfigRenderer.generate_config_file(template_args, tmp_dir)
+      expected_file_path = "#{tmp_dir}/agent.yml"
+
+      assert File.exists?(expected_file_path)
+      assert File.read!(expected_file_path) == File.read!("#{__DIR__}/expected_output_config_post_v0_26.yml")
+    end
   end
 end

test/prom_ex/grafana_agent/expected_output_config.yml

@@ -1,7 +1,7 @@
 server:
+  log_level: error
   http_listen_port: 12345
   grpc_listen_port: 54321
-  log_level: error
 
 prometheus:
   wal_directory: "/tmp/test/wal"
@@ -17,7 +17,7 @@ prometheus:
           static_configs:
             - targets: ["localhost:1234"]
           metric_relabel_configs:
-            - source_labels: [ instance ]
+            - source_labels: [instance]
               target_label: instance
               action: replace
               replacement: "localhost"

test/prom_ex/grafana_agent/expected_output_config_post_v0_26.yml

@@ -0,0 +1,27 @@
+server:
+  log_level: error
+
+prometheus:
+  wal_directory: "/tmp/test/wal"
+  global:
+    scrape_interval: 5s
+  configs:
+    - name: TestApp
+      scrape_configs:
+        - job_name: TestApp
+          metrics_path: /cool-metrics
+          scheme: https
+          bearer_token: "super_secret"
+          static_configs:
+            - targets: ["localhost:1234"]
+          metric_relabel_configs:
+            - source_labels: [instance]
+              target_label: instance
+              action: replace
+              replacement: "localhost"
+
+      remote_write:
+        - url: "www.my-prometheus.com"
+          basic_auth:
+            username: "prom_user"
+            password: "prom_pass"