HTTP Traffic Logger
This is intended to be used to record HTTP traffic between a backend data source plugin and
the target API for debugging purposes. For example, let's say a user is attempting to demonstrate a bug
with the GitHub data source plugin that is not reproducible with the developer's personal account. Currently,
it would be very difficult to determine the cause of the bug without having access to the user's GitHub account. With the
HTTP logger, the workflow would look like this:
- The user enables the HTTP logger for the GitHub data source plugin in their
grafana.ini
configuration file.
- The user reproduces the bug in their environment.
- The user reviews the HAR file generated by the HTTP logger in their browser's developer tools, and removes any sensitive information from the HAR file.
- The user shares the HAR file with the data source developer, along with a dashboard JSON that contains the queries used to reproduce the bug.
- The data source developer uses the E2E proxy in replay mode to replay the HTTP traffic recorded by the HTTP logger.
Enabling the HTTP Logger
To enable the HTTP logger for a plugin, add the following to your grafana.ini
configuration file:
[plugin.grafana-github-datasource]
har_log_enabled = true
har_log_path = /home/example/github.har
In the example above, grafana-github-datasource
is the plugin ID, which can be found in the plugin's src/plugin.json
file.
Adding Support for HTTP Logging in a Data Source Plugin
HTTPLogger
implements the http.RoundTripper
interface, and wraps the existing http.RoundTripper
implementation in
the data source plugin's HTTP client. For example, if the plugin's current HTTP client looks like this:
package client
import (
"net/http"
"github.com/grafana/grafana-plugin-sdk-go/backend/httpclient"
)
func getClient() (*http.Client, error) {
return httpclient.New()
}
Then, the HTTPLogger
can be added by wrapping the existing client.Transport
:
package client
import (
"net/http"
"github.com/grafana/grafana-plugin-sdk-go/backend/httpclient"
httplogger "github.com/grafana/grafana-plugin-sdk-go/experimental/http_logger"
)
func getClient() (*http.Client, error) {
client, err := httpclient.New()
if err != nil {
return nil, err
}
h := http_logger.NewHTTPLogger("grafana-example-datasource", client.Transport)
client.Transport = h
return client, nil
}
In the example above, grafana-example-datasource
is the plugin ID, which should match the id
property in the src/plugin.json
file.
By default, the HTTP logger will remove cookies and authorization headers from the HAR file, but the user should carefully
review the HAR file in their browser's dev tools to ensure that any sensitive information is removed from responses before sharing it with the data source developer.
Since HAR files are actually JSON files, the user can edit the responses in a text editor. The user should verify that their browser is still able to load the HAR file after editing is complete.
Local Debugging
Follow the E2E proxy's Quick Setup instructions to configure the proxy to replay the recorded traffic.
Make sure specify the path to the HAR file that the user shared in the proxy.json
file:
{
"storage": [{
"type": "har",
"path": "github.har"
}],
"address": "127.0.0.1:9999",
"hosts": ["github.com"]
}
Start the proxy in replay mode to avoid overwriting the original HAR file shared by the user:
mage e2e:replay
It will be simpler to reproduce the issue if you request that the user saves a dashboard JSON with the query that caused the bug. The dashboard should be using an absolute time range. This will ensure that the query will match the traffic recorded in the HAR file when the dashboard is loaded by the developer.