Live Traffic Section

The Live Traffic section provides essential features of Fiddler Everywhere.

Live Traffic displays a summary of each captured session in the Live Traffic list. It also provides functionalities to work with these sessions through the Live Traffic toolbar, the Inspectors types, and the corresponding Rules tab. The feature enables the saving and sharing of sessions, editing issued requests, marking, commenting sessions, and applying rules.

Defining a Session

A (web) session represents a single transaction between a client and a server, sometimes known as a request/response pair. Each session appears as a single entry in Live Traffic. Each session object has a Request and a Response, representing the data that the client has sent to the server and the data that the server has returned to the client. The session object also maintains a set of flags that record metadata about the session and a timers object that stores timestamps logged during the processing of the session.

Live Traffic toolbar and list

Live Traffic Toolbar

The toolbar of the Live Traffic section provides various functionalities such as filtering by various criteria, using preconfigured browser instance, searching, saving and sharing of sessions, and managing the user interface.

To start capturing traffic, enable Live Traffic by switching to the Capturing mode. To go into the Paused mode, use the Off switch state to pause the traffic capturing.

Live Traffic Toolbar

The Live Traffic toolbar provides the following functionalities:

Filtering Traffic

Use the filtering options (the Filters toolbar option and the column filters) to create and apply complex filters on your captured sessions in the Live Traffic list.

Learn more about the filtering options in Fiddler Everywhere...

Preconfigured Browser Capturing

Use the Open Browser button to capture traffic from a specific browser instance without the need to modify the system proxy settings.

Use the Open Browser button to start preconfigured browser instance

Learn more about the preconfigured browser capturing...

Removing All Sessions

Use the Remove All button to automatically remove all captured traffic from the Live Traffic list. To remove only specific sessions, select the desired ones and use the remove options from the context menu.

Searching

To search for specific values in the URL and the headers of all sessions, use the Search text input. The search action will immediately filter and show all sessions containing the search terms.

Saving Sessions

To save captured sessions, use the Save button, which will automatically save all captured traffic. To save only specific sessions, select the desired ones and use the advanced saving options from the context menu.

To save sessions for later or prepare sessions for sharing:

  1. Click the Save button. As a result, a Save Sessions prompt window appears.

  2. In the Save Sessions prompt window, enter a valid name and choose a folder to store the session.

  3. (Optional) Use the password protection switch to enable encryption and set a password. Only users with knowledge of the password can open the entry.

  4. Click Save. The saved session immediately loads in the Sessions list.

  5. Double-click the saved session to load it in a new Composer tab. Note that encrypted sessions will prompt for a password before loading.

Sharing Sessions

Sharing sessions dramatically improve collaboration, and Fiddler Everywhere provides the following options to export and share sessions:

  • Sharing through the Share button from a saved session entry in the Sessions list).

  • Sharing through the Share option from the Live Traffic list context menu.

  • Sharing through the Share button from the Live Traffic list toolbar. The Live Traffic toolbar comes with a Share button that will save in a file the currently displayed sessions, captured from Live Traffic, and then will share them through an explicitly provided email.

To share a session through the toolbar:

  1. Click the Share button. As a result, the Save Session prompt window appears.

  2. In the Save Sessions prompt window, enter a valid name and choose a folder to store the session.

  3. In the Share Sessions prompt window, enter a valid email and click Share. Entering notes is optional.

Managing Columns

Use the Columns option to manage which columns to show up in the Live Traffic list.

Learn more about each column present in the Live Traffic list here...

Toggling Layout

The last icon on the right side of the toolbar presents an option to restructure the foremost Fiddler Everywhere layout structure for the Live Traffic List and the Inspectors. The layout change option is available for the Live traffic tab, comparison tabs, and saved sessions tabs. The layout options are as follows:

  • (Default layout) Live Traffic List on the left side and the Inspectors on the right (top for Request Inspectors and bottom for Response Inspectors).
  • (Alternative layout) Live Traffic List at the top and the Inspectors at the bottom (left for Request Inspectors and right for Response Inspectors).

You can collpase the side-panels (Sessions and Requests) and toggle the main layout to optimize your working space.

Fiddler Everywhere with collapsed side panels and toggled layout

Live Traffic List

The Live Traffic list displays a list of web sessions with a summary of each captured session.

Live Traffic

Many operations begin by selecting one or more entries in the Live Traffic and activating other features.

  • To select more than one session, hold the Ctrl (Command on Mac) or Shift keys while clicking the desired rows.

  • Double-click or press Enter (Return on Mac) to activate the default inspectors for a single selected session.

When the Inspectors are activated, they will automatically decide which inspector type is best suited to display the request and response of the selected session.

List Icons

The Live Traffic List uses icons to provide additional context for each recorded session. To trigger an explanatory tooltip, hover over a Live Traffic list entry icon.

The following table displays the icons which Live Traffic supports for its list:

Icon Name Description
Represents a generic successful response.
Uploading content for a session in progress (the request is being sent to the server).
Uploading paused for session in progress.
Downloading content for session in progress (the response is being read from the server).
Downloading paused for session in progress.
The session was aborted by the client, Fiddler, or the Server.
The response was a server error.
The response returned status code 401 Unauthorized.
The response redirect status code 300, 301, 302, 303 or 307.
A tunnel is used for WebSocket traffic.
The request used the HTTP CONNECT method - establishes a tunnel used for HTTPS traffic.
A tunnel used for RPC traffic.
No content loaded.
Not modified.
Partial content.
The response was an image.
The response was a JavaScript file.
The response was a CSS file.
The response was an HTML file.
The response was a Flash file.
The response was an XML file.
The response was a Silverlight file.
The response was an audio file.
The response was a video file.
The response was a font file.
The response was a JSON file.
The request used the POST method.

Certificate Indicators

Each list icon can contain an additional triangle warning that indicates different server certificate issues.

  • A small orange triangle warning indicates that the server uses a certificate that is about to expire within 30 days. You can expand and inspect the certificate expiration warning in detail through the Response inspector notification.

    Certificate expiring note

  • A small red triangle warning indicates that there are certificate errors. You can expand and inspect the certificate error in detail through the Response inspector notification.

    Certificate error note

  • Absence of the triangle warning means no issues with the server certificate. You can still expand and inspect the used certificate in detail through the Response inspector notification.

    Valid Certificate details

Learn more about how to use the server certificate details in Fiddler Everywhere here...

Columns

The following table lists the Live Traffic columns and the key information they display.

Column name Description
# A unique identification number generated by Fiddler Everywhere. The column also contains an icon that represents the session type and might contain certificate expiration indicator.
Protocol The protocol type (HTTP or HTTPS) used by the session.
Host The hostname and the server's port to which the request was sent. The column also indicates requests with CONNECT method with the Tunnel to value (CONNECT tunnels in Fiddler).
Path The path refers to the exact location of a page, post, file, or another asset. The path resides after the hostname and is separated by a forward slash (/).
URL The URL contains the protocol, the hostname, the port, and the path from the request.
HTTP Version The protocol version used for communication between the client and the server (HTTP/1.1, HTTP/2, HTTP/2 + HTTP/1.1, and HTTP/1.1 + HTTP/2
Status Code The HTTP response status code
Method The HTTP method used by the request that was made (GET, POST, PUT, and so on)
Process The local OS process from which the traffic originated—for example, `chrome:8212` indicates a Google Chrome browser instance.
Client IP Indicates the client IP that sent this request. Mostly applicable when multiple computers on a network are pointed to a single Fiddler instance.
Remote IP Indicates the IP address of the server used for this request.
Body Size The number of bytes in the response body.
Caching Values from the Expires and Cache-Control headers of the response.
Content-Type The Content-Type header from the response.
Request Time Indicates when the session was executed in an HH:MM:SS:ms format.
Request Date Indicates the date when the session was executed in a MM:DD:YYYY format.
Duration Indicates the duration (in milliseconds) that took for the session to complete.
Rules Modified Indicates if the session is modified by active rules from the Rules tab.
Comments Shows the custom comments added by you or the author of a shared session.

Traffic Sorting and Filtering

By default, the captured traffic is sorted in the order sessions appear during the traffic capturing, sorted by the unique identification number column, and no active filters are applied. You can use the built-in sorting and filtering options to optimize the outcome.

Sorting Options

To create a custom sorting order, click the desired column. For example, click the URL column to sort alphabetically based on the URL, or click the Body Size column to sort based on the session size in bytes. The default sorting order is based on the unique identification number (order of appearance).

Filtering Options

Each column comes with a filter button, which popups an additional Filter menu.

The column Filter menu enables you to easily add filters for the currently selected column —for example, filter all the traffic by the host name or by a specific status code. Columns with active filters will have a blue filter indicator. You can remove a column filter through the Clear button in the Filter menu (for the filtered column) or through the Filters toolbar option.

column fulter menu

Apply complex filters by using the Filters toolbar option or learn more about the Column Filters options

Context Menu Options

The context menu for the Live Traffic exposes actions that you can apply for one or more sessions. To show the context menu, right-click (Windows OS), or press Control and mouse-click (macOS).

Live Traffic context menu

Editing in the Composer

The Edit in Composer context menu option loads the selected request in a new composer window where it can be edited, saved for later usage and sharing, and reissued.

Saving

To save selected sessions, use the Save context menu option. The saved sessions will appear in the Sessions list to the left of the Fiddler Everywhere interface and from there you can later re-open, export, and share them.

  • Selected sessions—Saves all chosen sessions; can be accessed with the keyboard by pressing S.

  • Unselected sessions—Saves all unselected Sessions; can be accessed with the keyboard by pressing Shift +Cmd +S (on Mac), or Shift+S (on Windows).

  • All Sessions—Saves all captured traffic; can be accessed with the keyboard by pressing Cmd+S (on Mac), or Ctrl+S (on Windows).

All options will display a Save prompt window. To save the desired sessions:

  1. Select the sessions, open the context menu, and click the Save option.

  2. Enter your session name and choose the folder that will store the entry.

  3. (Optional) Use the password protection switch to enable encryption and set a password. Only users with knowledge of the password will be able to open the entry.

  4. Click Save. The saved session immediately loads in the Sessions list.

  5. Double-click the saved session to load it in a new Composer tab. Note that encrypted sessions will prompt for a password before loading.

Alternatively, you can save all captured traffic through the Save button from the toolbar.

Sharing

The Share context menu option enables the sharing of sessions. Before any session is shared, it is saved as an entry in the Sessions list. Then, the entry can be transmitted through the email.

  • Selected sessions—Saves and shares all selected sessions.

  • Unselected sessions—Saves and shares all unselected sessions.

  • All Sessions—Saves and shares all captured traffic.

All options will initially display a Save and then a Share prompt window.

  1. Select the sessions, open the context menu, and click the Share option.

  2. The selected sessions are being saved. Enter your session name and click Save and proceed.

  3. The Share prompt window appears. Enter a valid email and, optionally, add notes. Once ready, click Share. Note that when sharing an encrypted session, the recipient will need the password to access it.

Alternatively, you can share captured traffic through the Share button from the toolbar.

Exporting

The Export context menu option allows you to export the captured traffic in various formats such as SAZ, HTTPArchive, WCAT, MeddlerScript, cURLScript, and more.

  • Selected sessions—Saves and shares all selected sessions.

  • Unselected sessions—Saves and shares all unselected sessions.

  • All Sessions—Saves and shares all captured traffic.

Removing

To delete sessions from your Live Traffic list, use the Remove context menu options.

  • Selected sessions—Removes all selected sessions; can be accessed with the keyboard by pressing Cmd+Back (on Mac), Del (on Windows).

  • Unselected sessions—Removes all unselected sessions; can be accessed with the keyboard by pressing Shift+Cmd+Back (on Mac), or Shift+Del (on Windows).

  • All Sessions—Removes all captured traffic; can be accessed with the keyboard by pressing Cmd+X (on Mac), or Ctrl+X (on Windows).

Commenting

To add comments on single or multiple sessions, use the Comment context menu option.

  1. Select the sessions, open the context menu, and click the Comment option, which can be accessed with the keyboard by pressing M.

  2. A Comment dialog appears. Enter the comment and click Ok.

  3. The text is added to the comment field for the selected sessions.

Saved and shared sessions will contain the added comments.

Marking

To apply colors or to strike out single or multiple sessions, use the Mark context menu option.

  1. Select the sessions, open the context menu, and click the Mark option.

  2. Click the preferred marking style to apply it.

Saved and shared sessions will contain the custom marking.

Replaying

To replay previously captured sessions, use the Replay context menu option, which can be accessed with the keyboard by pressing R.

Selecting

To select sessions directly related to the currently selected session, use the Select context menu option. You choose parent, children, and duplicate sessions.

  • Parent request—selects the session that is a parent of the currently selected session; can be accessed with the keyboard by pressing P.

  • Children requests—selects the sessions that are children of the currently selected session; can be accessed with the keyboard by pressing C.

  • Duplicate request—selects the session that is identical to the currently selected session; can be accessed with the keyboard by pressing D.

Copying

To place session information in the clipboard, use the Copy context menu option, which supports the following options:

  • URL—provides the session URL; can be accessed with the keyboard by pressing Cmd+U (on Mac), or Ctrl+U (on Windows).

  • Full Summary—provides verbose session details; can be accessed with the keyboard by pressing Cmd+C (on Mac), or Ctrl+C (on Windows).

  • Copy as Powershell—converts the request as a Powershell code and puts it in the system clipboard.

  • Copy as Fetch—converts the request as a Fetch code and puts it in the system clipboard.

  • Copy as Curl—converts the request as a Curl command and puts it in the system clipboard.

  • Copy as Python (requests)—converts the request as a Python code and puts it in the system clipboard.

Comparing

Select two sessions and use the Compare context menu option to load the Compare Sessions tab.

Learn more on how to compare sessions with Fiddler Everywhere here...

Adding Sessions to Compare Groups

Add sessions to compare groups through the Add to compare groups. This functionality allows you to add and inspect more sessions in the Compare Sessions tab.

Learn more on how to work with compare groups here...

Adding New Rules

You can use a captured session entry to mock some server behavior. For similar cases, you can use the session URL alongside the Rules tab. Creating rules allows you to test complex scenarios and various mock responses.

To add a new rule:

  1. Select the desired session entry and right-click to open the context menu. Select Add New Rule.

  2. A new rule is automatically created. The rule will use the URL from the selected session entry and, by default, will apply the initial response through the Return manually crafted response action option.

Bypassing the Proxy

The Bypass option allows you to quickly add domains that the Fiddler Everywhere proxy will explicitly bypass. To add a domain to the bypass list:

  1. Select the desired session entry.

  2. Right-click to open the context menu

  3. Select Bypass > Add to the bypass list.

Consider the following rules when bypassing a domain: