Add more formatting functions and function chaining

Signed-off-by: Drew Corlin <[email protected]>

Author: drewcorlin1

content/docs/next-release-v2/frontend-ui.md

@@ -154,9 +154,13 @@ Further, the trace template fields are available for substitution in process/log
 #### Formatting
 
 In addition to interpolating fields into links, formatting functions can be used. The syntax is `#{field | function}` (eg `#{endTime | epoch_micros_to_date_iso}'`). The available formatting functions and a description of their behavior are:
-| Function | Description | Example |
-| -------- | ----------- | ------- |
-| `epoch_micros_to_date_iso` | Format a date in microseconds since epoch to an ISO date time | `#{endTime \| epoch_micros_to_date_iso}` |
+| Function name | Arguments | Description | Example |
+| ------------- | --------- | ----------- | ------- |
+| `epoch_micros_to_date_iso` | - | Format a date in microseconds since epoch to an ISO date time | `#{endTime \| epoch_micros_to_date_iso}` |
+| `pad_start` | 1.`targetLength`(integer) 2.`padCharacter`(string) | Pad the start of a string with a given character until the resulting string reaches the given length. Behavior is implemented by and thus matches javascript's [String.padStart](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/padStart) | `#{traceID \| pad_start 32 0}`|
+| `add` | 1.`offset`(integer) | Add a value to another number. Can be positive or negative | `#{startTime \| add 1000000}`|
+
+Formatting functions can be chained together. For example `#{startTime | add 60000000 | epoch_micros_to_date_iso}`.
 
 ## Embedded Mode
 

content/docs/next-release/frontend-ui.md

@@ -154,9 +154,13 @@ Further, the trace template fields are available for substitution in process/log
 #### Formatting
 
 In addition to interpolating fields into links, formatting functions can be used. The syntax is `#{field | function}` (eg `#{endTime | epoch_micros_to_date_iso}'`). The available formatting functions and a description of their behavior are:
-| Function | Description | Example |
-| -------- | ----------- | ------- |
-| `epoch_micros_to_date_iso` | Format a date in microseconds since epoch to an ISO date time | `#{endTime \| epoch_micros_to_date_iso}` |
+| Function name | Arguments | Description | Example |
+| ------------- | --------- | ----------- | ------- |
+| `epoch_micros_to_date_iso` | - | Format a date in microseconds since epoch to an ISO date time | `#{endTime \| epoch_micros_to_date_iso}` |
+| `pad_start` | 1.`targetLength`(integer) 2.`padCharacter`(string) | Pad the start of a string with a given character until the resulting string reaches the given length. Behavior is implemented by and thus matches javascript's [String.padStart](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/padStart) | `#{traceID \| pad_start 32 0}`|
+| `add` | 1.`offset`(integer) | Add a value to another number. Can be positive or negative | `#{startTime \| add 1000000}`|
+
+Formatting functions can be chained together. For example `#{startTime | add 60000000 | epoch_micros_to_date_iso}`.
 
 ## Embedded Mode