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README.md

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 # mackerel-remora
-[WIP] Remora for Mackerel ( mackerel.io )
+Remora is agent for Mackerel ( mackerel.io ) to post service metrics
+
+![remora](https://user-images.githubusercontent.com/1097533/55680852-4b7e2e00-595a-11e9-88c9-8624f3ff5332.png)
+
+## features
+
+- Post service metrics
+
+
+## How to use
+For example, using `docker-compose` .
+
+```yml
+remora:
+  image: aknow/mackerel-remora:latest
+  volumes:
+      - .:/app
+  environment:
+    MACKEREL_REMORA_CONFIG: /app/_example/sample.yml
+```
+
+`sample.yml` is a config for `mackerel-remora` . The following is an example of its contents.
+
+```yml
+apikey: xxxxx
+plugin:
+  servicemetrics:
+    demo:
+      sample:
+        command: sh /app/_example/demo.sh
+```
+
+An example of the contents of `/app/_example/demo.sh` is:
+
+```sh
+#!/bin/sh
+
+metric_name="demo.test_metric.number"
+# metric number to post
+metric=6
+date=`date +%s`
+
+echo "${metric_name}\t${metric}\t${date}"
+```
+
+
+If you execute `docker-compose up -d remora` and wait for a while, it looks like on Mackerel:
+
+<img width="882" src="https://user-images.githubusercontent.com/1097533/55680926-3b1a8300-595b-11e9-8576-9ba525750763.png">
+
+
+## Config file format
+
+```yml
+apibase: <apibase>
+apikey: <apikey>
+root: <rootdir>
+plugin:
+  servicemetrics:
+    <servicename>:
+      <settingname>:
+        command: <command>
+        user: <user>
+        env:
+          <envkey>: <envvalue>
+```
+
+
+- `<apibase>`
+    - You can specify the domain of request destination API. It is usually unnecessary to specify.
+- `<apikey>`
+    - API key issued by the Mackerel organization to which you are posting. Requires write permission.
+- `<root>`
+    - Root directory of mackerel-remora. It is usually unnecessary to specify.
+- `<servicename>`
+    - Destination service name. You need to create a service on Mackerel beforehand.
+- `<settingname>`
+    - Plugin setting name for posting service metrics. It should not be used, but should not be duplicated.
+- `<command>`
+    - A command to perform standard output expected as a service metric plug-in.
+    - Remora expect standard output in the format `{metric name}\t{metric value}\t{epoch seconds}` as a result of executing this command.
+- `<user>`
+    - User of `command` running.
+- `<envkey>`
+    - Variable name of the environment variable to pass to the `command` .
+- `<envvalue>`
+    - Value of the environment variable to pass to the `command` .