From 0c0de275270f937aaebdbd137bb15dfd768a5b38 Mon Sep 17 00:00:00 2001
From: "Ryan J. Geyer" <me@ryangeyer.com>
Date: Thu, 24 Aug 2023 15:04:49 -0700
Subject: [PATCH 1/3] Initial commit of mysql integration module

---
 modules/grafana-cloud/integrations/README.md  | 11 +++
 .../integrations/mysql/README.md              | 72 +++++++++++++++++++
 .../integrations/mysql/module.river           | 68 ++++++++++++++++++
 3 files changed, 151 insertions(+)
 create mode 100644 modules/grafana-cloud/integrations/README.md
 create mode 100644 modules/grafana-cloud/integrations/mysql/README.md
 create mode 100644 modules/grafana-cloud/integrations/mysql/module.river

diff --git a/modules/grafana-cloud/integrations/README.md b/modules/grafana-cloud/integrations/README.md
new file mode 100644
index 0000000..c31f384
--- /dev/null
+++ b/modules/grafana-cloud/integrations/README.md
@@ -0,0 +1,11 @@
+# Grafana Cloud Integrations
+
+Module library to apply the opinionated configurations for Grafana Cloud [Integrations](https://grafana.com/docs/grafana-cloud/monitor-infrastructure/integrations/integration-reference/)
+
+## Design principals
+
+These modules will *only* apply the opinionated configuration details for a given integration.
+
+Usually, this means that a module will primarily require arguments for input and output. I.E. `metrics_targets`, `metrics_forward_to`, `logs_targets`, `logs_forward_to`.
+
+The module consumer will be responsible for discovering the targets, and configuring an end-of-line receiver (usually a remote write component).
\ No newline at end of file
diff --git a/modules/grafana-cloud/integrations/mysql/README.md b/modules/grafana-cloud/integrations/mysql/README.md
new file mode 100644
index 0000000..4a7621a
--- /dev/null
+++ b/modules/grafana-cloud/integrations/mysql/README.md
@@ -0,0 +1,72 @@
+# MySQL integration
+Module which performs expected transformations and labeling for the [MySQL integration](https://grafana.com/docs/grafana-cloud/monitor-infrastructure/integrations/integration-reference/integration-mysql/)
+
+## Usage
+Because the instance name is an argument to this module, the module must be re-used for each MySQL instance you wish to observe.
+
+Some examples can be found below.
+
+### Multiple instances on the same host
+
+Note that this is an unrealistic example since the hosts would likely be different, and the log files in the same location on each host.
+
+```
+module.git "grafana_cloud" {
+  repository = "https://github.com/grafana/agent-modules.git"
+  revision   = "main"
+  path       = "modules/grafana-cloud/autoconfigure/module.river"
+
+  arguments {
+    stack_name = "<stack name>"
+    token = "<stack token>"
+  }
+}
+
+prometheus.exporter.mysql "mysqlprimary" {
+  data_source_name = "<username>:<password>@(<host>:<port>)/"
+}
+
+loki.source.file "mysqlprimary" {
+  targets = [
+    { __path__ = "/var/log/mysql/mysqlprimary.log" },
+  ]
+  forward_to = [module.file.mysqlprimary.exports.logs_receiver]
+}
+
+module.file "mysqlprimary" {
+  filename = "/config/modules/grafana-cloud/integrations/mysql/module.river"
+
+  arguments {
+    instance = "Primary"
+    metrics_targets = prometheus.exporter.mysql.mysqlprimary.targets
+    metrics_receiver = [module.file.grafana_cloud.exports.metrics_receiver]
+    logs_receiver = [module.file.grafana_cloud.exports.logs_receiver]
+  }
+}
+
+prometheus.exporter.mysql "mysqlsecondary" {
+  data_source_name = "<username>:<password>@(<host>:<port>)/"
+}
+
+loki.source.file "mysqlsecondary" {
+  targets = [
+    { __path__ = "/var/log/mysql/mysqlsecondary.log" },
+  ]
+  forward_to = [module.file.mysqlsecondary.exports.logs_receiver]
+}
+
+module.file "mysqlsecondary" {
+  filename = "/config/modules/grafana-cloud/integrations/mysql/module.river"
+
+  arguments {
+    instance = "Secondary"
+    metrics_targets = prometheus.exporter.mysql.mysqlsecondary.targets
+    metrics_receiver = [module.file.grafana_cloud.exports.metrics_receiver]
+    logs_receiver = [module.file.grafana_cloud.exports.logs_receiver]
+  }
+}
+```
+
+### Multiple instances with kuberenetes discovery
+
+Placeholder
\ No newline at end of file
diff --git a/modules/grafana-cloud/integrations/mysql/module.river b/modules/grafana-cloud/integrations/mysql/module.river
new file mode 100644
index 0000000..3235094
--- /dev/null
+++ b/modules/grafana-cloud/integrations/mysql/module.river
@@ -0,0 +1,68 @@
+/********************************************
+ * ARGUMENTS
+ ********************************************/
+argument "instance" {}
+
+argument "metrics_targets" {}
+
+argument "metrics_receiver" {}
+
+argument "logs_receiver" {}
+
+/********************************************
+ * EXPORTS
+ ********************************************/
+export "logs_receiver" {
+  value = loki.relabel.job_instance.receiver
+}
+
+/********************************************
+ * Metrics scrape and relabel
+ ********************************************/
+prometheus.scrape "mysql" {
+  job_name = "integrations/mysql"
+  targets = argument.metrics_targets.value
+  forward_to = [prometheus.relabel.instance.receiver]
+}
+
+prometheus.relabel "instance" {
+  forward_to = argument.metrics_receiver.value
+
+  rule {
+    target_label = "instance"
+    replacement = argument.instance.value
+  }
+}
+
+/********************************************
+ * Logs relabel and pipeline stages
+ ********************************************/
+loki.relabel "job_instance" {
+  forward_to = [loki.process.stages.receiver]
+  rule {
+    target_label = "instance"
+    replacement = argument.instance.value
+  }
+  rule {
+    target_label = "job"
+    replacement = "integrations/mysql"
+  }
+}
+
+loki.process "stages" {
+  forward_to = argument.logs_receiver.value
+  stage.regex {
+    expression = "(?P<timestamp>.+) (?P<thread>[\\d]+) \\[(?P<label>.+?)\\]( \\[(?P<err_code>.+?)\\] \\[(?P<subsystem>.+?)\\])? (?P<msg>.+)"
+  }
+  stage.labels {
+    values = {
+      level = "label",
+      err_code = "",
+      subsystem = "",
+    }
+  }
+  stage.drop {
+    expression = "^ *$"
+    drop_counter_reason = "drop empty lines"
+  }
+}
\ No newline at end of file

From a1032989ba0566d587979e6030335c7b21f61ae4 Mon Sep 17 00:00:00 2001
From: "Ryan J. Geyer" <me@ryangeyer.com>
Date: Wed, 6 Sep 2023 10:01:33 -0700
Subject: [PATCH 2/3] Update mysql agent-module readme

---
 .../integrations/mysql/README.md              | 62 ++++++++++++++++++-
 1 file changed, 59 insertions(+), 3 deletions(-)

diff --git a/modules/grafana-cloud/integrations/mysql/README.md b/modules/grafana-cloud/integrations/mysql/README.md
index 4a7621a..aec0a1a 100644
--- a/modules/grafana-cloud/integrations/mysql/README.md
+++ b/modules/grafana-cloud/integrations/mysql/README.md
@@ -6,7 +6,9 @@ Because the instance name is an argument to this module, the module must be re-u
 
 Some examples can be found below.
 
-### Multiple instances on the same host
+### Linux/MacOS/Windows (single host)
+
+#### Multiple instances on the same host
 
 Note that this is an unrealistic example since the hosts would likely be different, and the log files in the same location on each host.
 
@@ -67,6 +69,60 @@ module.file "mysqlsecondary" {
 }
 ```
 
-### Multiple instances with kuberenetes discovery
+### Kubernetes
+
+#### K8s Monitoring Helm Chart
+
+When using the k8s monitoring helm chart, we will take advantage of the existing extensibility of the `logs.extraConfig` configuration value. This is also the current approach for the k8s app, with the exception of the introduction of the agent-module.
+
+logs.extraConfig:
+```
+// ******************************************************************************************************************************************//
+// START: MySQL Integration extra config for the instance named "k8s MAD Primary"                                                            //
+// ******************************************************************************************************************************************//
+// New relabel for each mysql instance for which we wish to fetch pod logs.
+// Appends to the relabeling which was already done by the k8s helm chart discovery relabeling which adds namespace, pod, job, and calculates the pod log path on the host
+// Drops all other pods
+discovery.relabel "mysqlmadprimary_pod_logs" {
+  targets = discovery.relabel.pod_logs.output
+
+  rule {
+    source_labels = ["__meta_kubernetes_pod_label_app_kubernetes_io_name","__meta_kubernetes_pod_label_app_kubernetes_io_instance","__meta_kubernetes_pod_label_app_kubernetes_io_component"]
+    regex = "mysql;mysql-mad;primary"
+    action = "keep"
+  }
+}
+
+// Direct copy/paste duplication of the file match in the k8s helm chart. Needs to be duplicated for each instance, since we're (re) discovering and relabeling for eacn instance.
+local.file_match "mysqlmadprimary_pod_logs" {
+  path_targets = discovery.relabel.mysqlmadprimary_pod_logs.output
+}
+
+loki.source.file "mysqlmadprimary_pod_logs" {
+  targets = local.file_match.mysqlmadprimary_pod_logs.targets
+  forward_to = [loki.process.mysqlmadprimary_pod_logs.receiver]
+}
+
+loki.process "mysqlmadprimary_pod_logs" {
+  stage.cri {} // Also duplication from the k8s helm chart, but crucially, this is copy/pasted, and might not match the setting in the chart.
+  forward_to = [module.git.mysqlmadprimary.exports.logs_receiver]
+}
+
+prometheus.remote_write "blackhole" {}
+
+module.git "mysqlmadprimary" {
+  repository = "https://github.com/grafana/agent-modules.git"
+  revision = "0c0de275270f937aaebdbd137bb15dfd768a5b38"
+  path = "modules/grafana-cloud/integrations/mysql/module.river"
 
-Placeholder
\ No newline at end of file
+  arguments {
+    instance = "k8s MAD Primary"
+    metrics_targets = [] // Blank, because this is the logs instance of k8s. This may be an indicator that the module needs to be broken into logs and metrics
+    metrics_receiver = [prometheus.remote_write.blackhole.receiver]
+    logs_receiver = [loki.write.grafana_cloud_loki.receiver]
+  }
+}
+// ******************************************************************************************************************************************//
+// END: MySQL Integration extra config for the instance named "k8s MAD Primary"                                                              //
+// ******************************************************************************************************************************************//
+```

From 9adeefb66ac1893524d39ae9bef9e6a7467f3fd1 Mon Sep 17 00:00:00 2001
From: "Ryan J. Geyer" <me@ryangeyer.com>
Date: Wed, 6 Sep 2023 10:09:42 -0700
Subject: [PATCH 3/3] Added single instance use-case to mysql integration
 readme

---
 .../integrations/mysql/README.md              | 38 +++++++++++++++++++
 1 file changed, 38 insertions(+)

diff --git a/modules/grafana-cloud/integrations/mysql/README.md b/modules/grafana-cloud/integrations/mysql/README.md
index aec0a1a..ffb2246 100644
--- a/modules/grafana-cloud/integrations/mysql/README.md
+++ b/modules/grafana-cloud/integrations/mysql/README.md
@@ -8,6 +8,44 @@ Some examples can be found below.
 
 ### Linux/MacOS/Windows (single host)
 
+#### Single instance on one host
+
+```
+module.git "grafana_cloud" {
+  repository = "https://github.com/grafana/agent-modules.git"
+  revision   = "main"
+  path       = "modules/grafana-cloud/autoconfigure/module.river"
+
+  arguments {
+    stack_name = "<stack name>"
+    token = "<stack token>"
+  }
+}
+
+prometheus.exporter.mysql "mysql" {
+  data_source_name = "<username>:<password>@(<host>:<port>)/"
+}
+
+loki.source.file "mysql" {
+  targets = [
+    { __path__ = "/var/log/mysql/mysql.log" },
+  ]
+  forward_to = [module.file.mysql.exports.logs_receiver]
+}
+
+module.file "mysql" {
+  filename = "/config/modules/grafana-cloud/integrations/mysql/module.river"
+
+  arguments {
+    instance = "<mysql instance name>"
+    metrics_targets = prometheus.exporter.mysql.mysql.targets
+    metrics_receiver = [module.file.grafana_cloud.exports.metrics_receiver]
+    logs_receiver = [module.file.grafana_cloud.exports.logs_receiver]
+  }
+}
+```
+
+
 #### Multiple instances on the same host
 
 Note that this is an unrealistic example since the hosts would likely be different, and the log files in the same location on each host.