docs: add docs for prom and loki with pipeline

docs/user-guide/ingest-data/for-observability/loki.md

@@ -125,4 +125,35 @@ WITH(
   append_mode = 'true'
 )
 1 row in set (0.00 sec)
-```
+```
+
+## Using pipeline in Loki push API
+
+:::warning Experimental Feature
+This experimental feature may contain unexpected behavior, have its functionality change in the future.
+:::
+
+Starting from `v0.15`, GreptimeDB supports using pipeline to process Loki push requests.
+You can simply set the HTTP header `x-greptime-pipeline-name` to the target pipeline name to enable pipeline processing.
+
+Note, if the request data go through the pipeline engine, GreptimeDB will add prefix to the label and metadata column names:
+- `loki_label_` before each label name
+- `loki_metadata_` before each structured metadata name
+- The original Loki log line would be named `loki_line`
+
+An example of data model using `greptime_identity` would be like the following:
+```
+mysql> select * from loki_logs limit 1;
++----------------------------+---------------------+---------------------------+---------------------------------------------------------------------------+
+| greptime_timestamp         | loki_label_platform | loki_label_service_name   | loki_line                                                                 |
++----------------------------+---------------------+---------------------------+---------------------------------------------------------------------------+
+| 2025-07-15 11:40:26.651141 | docker              | docker-monitoring-alloy-1 | ts=2025-07-15T11:40:15.532342849Z level=info "boringcrypto enabled"=false |
++----------------------------+---------------------+---------------------------+---------------------------------------------------------------------------+
+1 row in set (0.00 sec)
+```
+
+You can see that the label column names are prefixed with `loki_label_`.
+The actual log line is named `loki_line`.
+You can use a custom pipeline to process the data. It would be working like a normal pipeline process.
+
+You can refer to the [pipeline's documentation](/user-guide/logs/pipeline-config.md) for more details.

docs/user-guide/ingest-data/for-observability/prometheus.md

@@ -217,6 +217,44 @@ It can also be helpful to group metrics by their frequency.
 Note, each metric's logical table is bound to a physical table upon creation.
 So setting different physical table for the same metric within the same database won't work.
 
+## Using pipeline in remote write
+
+:::warning Experimental Feature
+This experimental feature may contain unexpected behavior, have its functionality change in the future.
+:::
+
+Starting from `v0.15`, GreptimeDB supports using pipeline to process Prometheus remote write requests.
+You can simply set the HTTP header `x-greptime-pipeline-name` to the target pipeline name to enable pipeline processing.
+
+Here is a very simple pipeline configuration, using `vrl` processor to add a `source` label to each metric:
+```YAML
+version: 2
+processors:
+  - vrl:
+      source: |
+        .source = "local_laptop"
+        .
+
+transform:
+  - field: greptime_timestamp
+    type: time, ms
+    index: timestamp
+```
+
+The result looks something like this
+```
+mysql> select * from `go_memstats_mcache_inuse_bytes`;
++----------------------------+----------------+--------------------+---------------+--------------+
+| greptime_timestamp         | greptime_value | instance           | job           | source       |
++----------------------------+----------------+--------------------+---------------+--------------+
+| 2025-07-11 07:42:03.064000 |           1200 | node_exporter:9100 | node-exporter | local_laptop |
+| 2025-07-11 07:42:18.069000 |           1200 | node_exporter:9100 | node-exporter | local_laptop |
++----------------------------+----------------+--------------------+---------------+--------------+
+2 rows in set (0.01 sec)
+```
+
+You can refer to the [pipeline's documentation](/user-guide/logs/pipeline-config.md) for more details.
+
 ## Performance tuning
 
 By default, the metric engine will automatically create a physical table named `greptime_physical_table` if it does not already exist. For performance optimization, you may choose to create a physical table with customized configurations.

i18n/zh/docusaurus-plugin-content-docs/current/user-guide/ingest-data/for-observability/loki.md

@@ -124,4 +124,35 @@ WITH(
   append_mode = 'true'
 )
 1 row in set (0.00 sec)
-```
+```
+
+## Using pipeline in Loki push API
+
+:::warning 实验性特性
+此实验性功能可能存在预期外的行为，其功能未来可能发生变化。
+:::
+
+从 `v0.15` 开始，GreptimeDB 支持使用 pipeline 来处理 Loki 的写入请求。
+你可以通过在 HTTP header 中将 `x-greptime-pipeline-name` 的值设置为需要执行的 pipeline 名称来使用 pipeline 处理流程。
+
+请注意，如果使用 pipeline 处理流程，GreptimeDB 将会在 label 和 structure metadata 的列名前加上前缀：
+- 对 label 列，加上 `loki_label_` 的前缀
+- 对 structured metadata 列，加上 `loki_metadata_` 的前缀
+- Loki 自身的日志行则会被命名为 `loki_line`
+
+一个使用 `greptime_identity` 的数据样例将如下所示：
+```
+mysql> select * from loki_logs limit 1;
++----------------------------+---------------------+---------------------------+---------------------------------------------------------------------------+
+| greptime_timestamp         | loki_label_platform | loki_label_service_name   | loki_line                                                                 |
++----------------------------+---------------------+---------------------------+---------------------------------------------------------------------------+
+| 2025-07-15 11:40:26.651141 | docker              | docker-monitoring-alloy-1 | ts=2025-07-15T11:40:15.532342849Z level=info "boringcrypto enabled"=false |
++----------------------------+---------------------+---------------------------+---------------------------------------------------------------------------+
+1 row in set (0.00 sec)
+```
+
+可以见到 label 列的名称加上了 `loki_label_` 的前缀。
+实际的日志列则被命名为 `loki_line`。
+你可以使用一个自定义的 pipeline 来处理数据，这将和其他 pipeline 处理流程一致。
+
+更多配置详情请参考 [pipeline 相关文档](/user-guide/logs/pipeline-config.md)。

i18n/zh/docusaurus-plugin-content-docs/current/user-guide/ingest-data/for-observability/prometheus.md

@@ -208,6 +208,44 @@ GreptimeDB 可以识别一些标签的名称，并将它们转换成写入时的
 
 注意，指标的逻辑表在创建时就与物理表一一关联。在同一数据库下为同一指标设定不同的物理表不会生效。
 
+## 在 Remote write 中使用 pipeline
+
+:::warning 实验性特性
+此实验性功能可能存在预期外的行为，其功能未来可能发生变化。
+:::
+
+从 `v0.15` 开始，GreptimeDB 支持在 Prometheus Remote Write 协议入口使用 pipeline 处理数据。
+你可以通过在 HTTP header 中将 `x-greptime-pipeline-name` 的值设置为需要执行的 pipeline 名称来使用 pipeline 处理流程。
+
+以下是一个非常简单的 pipeline 配置例子，使用 `vrl` 处理器来对每个指标增加一个 `source` 标签：
+```YAML
+version: 2
+processors:
+  - vrl:
+      source: |
+        .source = "local_laptop"
+        .
+
+transform:
+  - field: greptime_timestamp
+    type: time, ms
+    index: timestamp
+```
+
+结果如下所示
+```
+mysql> select * from `go_memstats_mcache_inuse_bytes`;
++----------------------------+----------------+--------------------+---------------+--------------+
+| greptime_timestamp         | greptime_value | instance           | job           | source       |
++----------------------------+----------------+--------------------+---------------+--------------+
+| 2025-07-11 07:42:03.064000 |           1200 | node_exporter:9100 | node-exporter | local_laptop |
+| 2025-07-11 07:42:18.069000 |           1200 | node_exporter:9100 | node-exporter | local_laptop |
++----------------------------+----------------+--------------------+---------------+--------------+
+2 rows in set (0.01 sec)
+```
+
+更多配置详情请参考 [pipeline 相关文档](/user-guide/logs/pipeline-config.md)。
+
 ## 性能优化
 
 默认情况下，metric engine 会自动创建一个名为 `greptime_physical_table` 的物理表。

i18n/zh/docusaurus-plugin-content-docs/version-0.15/user-guide/ingest-data/for-observability/loki.md

@@ -124,4 +124,35 @@ WITH(
   append_mode = 'true'
 )
 1 row in set (0.00 sec)
-```
+```
+
+## Using pipeline in Loki push API
+
+:::warning 实验性特性
+此实验性功能可能存在预期外的行为，其功能未来可能发生变化。
+:::
+
+从 `v0.15` 开始，GreptimeDB 支持使用 pipeline 来处理 Loki 的写入请求。
+你可以通过在 HTTP header 中将 `x-greptime-pipeline-name` 的值设置为需要执行的 pipeline 名称来使用 pipeline 处理流程。
+
+请注意，如果使用 pipeline 处理流程，GreptimeDB 将会在 label 和 structure metadata 的列名前加上前缀：
+- 对 label 列，加上 `loki_label_` 的前缀
+- 对 structured metadata 列，加上 `loki_metadata_` 的前缀
+- Loki 自身的日志行则会被命名为 `loki_line`
+
+一个使用 `greptime_identity` 的数据样例将如下所示：
+```
+mysql> select * from loki_logs limit 1;
++----------------------------+---------------------+---------------------------+---------------------------------------------------------------------------+
+| greptime_timestamp         | loki_label_platform | loki_label_service_name   | loki_line                                                                 |
++----------------------------+---------------------+---------------------------+---------------------------------------------------------------------------+
+| 2025-07-15 11:40:26.651141 | docker              | docker-monitoring-alloy-1 | ts=2025-07-15T11:40:15.532342849Z level=info "boringcrypto enabled"=false |
++----------------------------+---------------------+---------------------------+---------------------------------------------------------------------------+
+1 row in set (0.00 sec)
+```
+
+可以见到 label 列的名称加上了 `loki_label_` 的前缀。
+实际的日志列则被命名为 `loki_line`。
+你可以使用一个自定义的 pipeline 来处理数据，这将和其他 pipeline 处理流程一致。
+
+更多配置详情请参考 [pipeline 相关文档](/user-guide/logs/pipeline-config.md)。

i18n/zh/docusaurus-plugin-content-docs/version-0.15/user-guide/ingest-data/for-observability/prometheus.md

@@ -208,6 +208,44 @@ GreptimeDB 可以识别一些标签的名称，并将它们转换成写入时的
 
 注意，指标的逻辑表在创建时就与物理表一一关联。在同一数据库下为同一指标设定不同的物理表不会生效。
 
+## 在 Remote write 中使用 pipeline
+
+:::warning 实验性特性
+此实验性功能可能存在预期外的行为，其功能未来可能发生变化。
+:::
+
+从 `v0.15` 开始，GreptimeDB 支持在 Prometheus Remote Write 协议入口使用 pipeline 处理数据。
+你可以通过在 HTTP header 中将 `x-greptime-pipeline-name` 的值设置为需要执行的 pipeline 名称来使用 pipeline 处理流程。
+
+以下是一个非常简单的 pipeline 配置例子，使用 `vrl` 处理器来对每个指标增加一个 `source` 标签：
+```YAML
+version: 2
+processors:
+  - vrl:
+      source: |
+        .source = "local_laptop"
+        .
+
+transform:
+  - field: greptime_timestamp
+    type: time, ms
+    index: timestamp
+```
+
+结果如下所示
+```
+mysql> select * from `go_memstats_mcache_inuse_bytes`;
++----------------------------+----------------+--------------------+---------------+--------------+
+| greptime_timestamp         | greptime_value | instance           | job           | source       |
++----------------------------+----------------+--------------------+---------------+--------------+
+| 2025-07-11 07:42:03.064000 |           1200 | node_exporter:9100 | node-exporter | local_laptop |
+| 2025-07-11 07:42:18.069000 |           1200 | node_exporter:9100 | node-exporter | local_laptop |
++----------------------------+----------------+--------------------+---------------+--------------+
+2 rows in set (0.01 sec)
+```
+
+更多配置详情请参考 [pipeline 相关文档](/user-guide/logs/pipeline-config.md)。
+
 ## 性能优化
 
 默认情况下，metric engine 会自动创建一个名为 `greptime_physical_table` 的物理表。

versioned_docs/version-0.15/user-guide/ingest-data/for-observability/loki.md

@@ -125,4 +125,35 @@ WITH(
   append_mode = 'true'
 )
 1 row in set (0.00 sec)
-```
+```
+
+## Using pipeline in Loki push API
+
+:::warning Experimental Feature
+This experimental feature may contain unexpected behavior, have its functionality change in the future.
+:::
+
+Starting from `v0.15`, GreptimeDB supports using pipeline to process Loki push requests.
+You can simply set the HTTP header `x-greptime-pipeline-name` to the target pipeline name to enable pipeline processing.
+
+Note, if the request data go through the pipeline engine, GreptimeDB will add prefix to the label and metadata column names:
+- `loki_label_` before each label name
+- `loki_metadata_` before each structured metadata name
+- The original Loki log line would be named `loki_line`
+
+An example of data model using `greptime_identity` would be like the following:
+```
+mysql> select * from loki_logs limit 1;
++----------------------------+---------------------+---------------------------+---------------------------------------------------------------------------+
+| greptime_timestamp         | loki_label_platform | loki_label_service_name   | loki_line                                                                 |
++----------------------------+---------------------+---------------------------+---------------------------------------------------------------------------+
+| 2025-07-15 11:40:26.651141 | docker              | docker-monitoring-alloy-1 | ts=2025-07-15T11:40:15.532342849Z level=info "boringcrypto enabled"=false |
++----------------------------+---------------------+---------------------------+---------------------------------------------------------------------------+
+1 row in set (0.00 sec)
+```
+
+You can see that the label column names are prefixed with `loki_label_`.
+The actual log line is named `loki_line`.
+You can use a custom pipeline to process the data. It would be working like a normal pipeline process.
+
+You can refer to the [pipeline's documentation](/user-guide/logs/pipeline-config.md) for more details.

versioned_docs/version-0.15/user-guide/ingest-data/for-observability/prometheus.md

@@ -217,6 +217,44 @@ It can also be helpful to group metrics by their frequency.
 Note, each metric's logical table is bound to a physical table upon creation.
 So setting different physical table for the same metric within the same database won't work.
 
+## Using pipeline in remote write
+
+:::warning Experimental Feature
+This experimental feature may contain unexpected behavior, have its functionality change in the future.
+:::
+
+Starting from `v0.15`, GreptimeDB supports using pipeline to process Prometheus remote write requests.
+You can simply set the HTTP header `x-greptime-pipeline-name` to the target pipeline name to enable pipeline processing.
+
+Here is a very simple pipeline configuration, using `vrl` processor to add a `source` label to each metric:
+```YAML
+version: 2
+processors:
+  - vrl:
+      source: |
+        .source = "local_laptop"
+        .
+
+transform:
+  - field: greptime_timestamp
+    type: time, ms
+    index: timestamp
+```
+
+The result looks something like this
+```
+mysql> select * from `go_memstats_mcache_inuse_bytes`;
++----------------------------+----------------+--------------------+---------------+--------------+
+| greptime_timestamp         | greptime_value | instance           | job           | source       |
++----------------------------+----------------+--------------------+---------------+--------------+
+| 2025-07-11 07:42:03.064000 |           1200 | node_exporter:9100 | node-exporter | local_laptop |
+| 2025-07-11 07:42:18.069000 |           1200 | node_exporter:9100 | node-exporter | local_laptop |
++----------------------------+----------------+--------------------+---------------+--------------+
+2 rows in set (0.01 sec)
+```
+
+You can refer to the [pipeline's documentation](/user-guide/logs/pipeline-config.md) for more details.
+
 ## Performance tuning
 
 By default, the metric engine will automatically create a physical table named `greptime_physical_table` if it does not already exist. For performance optimization, you may choose to create a physical table with customized configurations.