Specifies transformations based on the route matches. The first matched transformation will be applied. If there are overlapped match conditions, please put the most specific match first.
stage
int
Only RouteTransformations.RouteTransformation with matching stage will be used with this filter.
logRequestResponseInfo
bool
Logs request/response sensitive information By default, this is false so no request or response sensitive information is logged. If set to true, the filter will log the request/response body and headers before and after any transformation is applied.
The route matching parameter. Only when the match is satisfied, the “requires” field will apply. For example: following match will match all requests. .. code-block:: yaml match: prefix: /.
Specifies a set of headers that the route should match on. The router will check the response headers against all the specified headers in the route config. A match will happen if all the headers in the route are present in the request with the same values (or based on presence if the value field is not in the config).
This type of transformation will make all the headers available in the response body. The resulting JSON body will consist of two attributes: ‘headers’, containing the headers, and ‘body’, containing the original body. Only one of headerBodyTransform, transformationTemplate, or transformerConfig can be set.
Configuration for an externally implemented transformer, used by envoy transformation filter. Only one of transformerConfig, transformationTemplate, or headerBodyTransform can be set.
Logs request/response sensitive information By default, this is false so no request or response sensitive information is logged. If set to true, the filter will log the request/response body and headers before and after this transformation is applied.
Extraction
Extractions can be used to extract information from the request/response.
The extracted information can then be referenced in template fields.
Extract information from the request/response body. Only one of body or header can be set.
regex
string
The regex field specifies the regular expression used for matching against the source content. - In EXTRACT mode, the entire source must match the regex. subgroup selects the n-th capturing group, which determines the part of the match that you want to extract. If the regex does not match the source, the result of the extraction will be an empty value. - In SINGLE_REPLACE mode, the regex also needs to match the entire source. subgroup selects the n-th capturing group that is replaced with the content of replacement_text. If the regex does not match the source, the result of the replacement will be the source itself. - In REPLACE_ALL mode, the regex is applied repeatedly to find all occurrences within the source that match. Each matching occurrence is replaced with the value in replacement_text. In this mode, the configuration is rejected if subgroup is set. If the regex does not match the source, the result of the replacement will be the source itself.
subgroup
int
If your regex contains capturing groups, use this field to determine the group that you want to select. Defaults to 0. If set in EXTRACT and SINGLE_REPLACE modes, the subgroup represents the capturing group that you want to extract or replace in the source. The configuration is rejected if you set subgroup to a non-zero value when using thev REPLACE_ALL mode.
The value replacement_text is used to format the substitution for matched sequences in in an input string. This value is only legal in SINGLE_REPLACE and REPLACE_ALL modes. - In SINGLE_REPLACE mode, the subgroup selects the n-th capturing group, which represents the value that you want to replace with the string provided in replacement_text. - In REPLACE_ALL mode, each sequence that matches the specified regex in the input is replaced with the value inreplacement_text. The replacement_text can include special syntax, such as $1, $2, etc., to refer to capturing groups within the regular expression. The value that is specified in replacement_text is treated as a string, and is passed to std::regex_replace as the replacement string. For more informatino, see https://en.cppreference.com/w/cpp/regex/regex_replace.
The mode of operation for the extraction. Defaults to EXTRACT.
Mode
The mode of operation for the extraction.
Name
Description
EXTRACT
Default mode. Extract the content of a specified capturing group. In this mode, subgroup selects the n-th capturing group, which represents the value that you want to extract.
SINGLE_REPLACE
Replace the content of a specified capturing group. In this mode, subgroup selects the n-th capturing group, which represents the value that you want to replace with the string provided in replacement_text. Note: replacement_text must be set for this mode.
REPLACE_ALL
Replace all regex matches with the value provided in replacement_text. Note: replacement_text must be set for this mode. Note: The configuration fails if subgroup is set to a non-zero value. Note: restrictions on the regex are different for this mode. See the regex field for more details.
If set to true, use JSON pointer notation (e.g. “time/start”) instead of dot notation (e.g. “time.start”) to access JSON elements. Defaults to false. Please note that, if set to ‘true’, you will need to use the extraction function to access extractors in the template (e.g. ‘{{ extraction(“my_extractor”) }}'); if the default value of ‘false’ is used, extractors will simply be available by their name (e.g. ‘{{ my_extractor }}').
extractors
map<string, .envoy.api.v2.filter.http.Extraction>
Use this attribute to extract information from the request. It consists of a map of strings to extractors. The extractor will defines which information will be extracted, while the string key will provide the extractor with a name. You can reference extractors by their name in templates, e.g. “{{ my-extractor }}” will render to the value of the “my-extractor” extractor.
Use this attribute to transform request/response headers. It consists of a map of strings to templates. The string key determines the name of the resulting header, the rendered template will determine the value. Any existing headers with the same header name will be replaced by the transformed header. If a header name is included in headers and headers_to_append, it will first be replaced the template in headers, then additional header values will be appended by the templates defined in headers_to_append. For example, the following header transformation configuration: yaml headers: x-header-one: {"text": "first {{inja}} template"} x-header-one: {"text": "second {{inja}} template"} headersToAppend: - key: x-header-one value: {"text": "first appended {{inja}} template"} - key: x-header-one value: {"text": "second appended {{inja}} template"} will result in the following headers on the HTTP message: x-header-one: first inja template x-header-one: first appended inja template x-header-one: second appended inja template.
Use this attribute to transform request/response headers. It consists of an array of string/template objects. Use this attribute to define multiple templates for a single header. Header template(s) defined here will be appended to any existing headers with the same header name, not replace existing ones. See headers documentation to see an example of usage.
headersToRemove
[]string
Attribute to remove headers from requests. If a header is present multiple times, all instances of the header will be removed.
This will cause the transformation filter not to buffer the body. Use this setting if the response body is large and you don’t need to transform nor extract information from it. Only one of passthrough, body, mergeExtractorsToBody, or mergeJsonKeys can be set.
Merge all defined extractors to the request/response body. If you want to nest elements inside the body, use dot separator in the extractor name. Only one of mergeExtractorsToBody, body, passthrough, or mergeJsonKeys can be set.
A set of key-value pairs to merge into the JSON body. Each value will be rendered separately, and then placed into the JSON body at the specified key. There are a number of important caveats to using this feature: * This can only be used when the body is parsed as JSON. * This option does NOT work with advanced templates currently. Only one of mergeJsonKeys, body, passthrough, or mergeExtractorsToBody can be set.
Use this field to set Inja behavior when rendering strings which contain characters that would need to be escaped to be valid JSON. Note that this sets the behavior for the entire transformation. Use raw_strings function for fine-grained control within a template.
HeaderToAppend
Defines a header-template pair to be used in headers_to_append
Instruct the filter to parse the rendered value as a proto Struct message before setting it as the metadata value.
RequestBodyParse
Determines how the body will be parsed.
Name
Description
ParseAsJson
Will attempt to parse the request/response body as JSON
DontParse
The request/response body will be treated as plain text
InjaTemplate
Defines an Inja template that will be
rendered by Gloo. In addition to the core template functions, the Gloo
transformation filter defines the following custom functions:
header(header_name): returns the value of the header with the given name.
extraction(extractor_name): returns the value of the extractor with the
given name.
env(env_var_name): returns the value of the environment variable with the
given name.
body(): returns the request/response body.
context(): returns the base JSON context (allowing for example to range on
a JSON body that is an array).
request_header(header_name): returns the value of the request header with
the given name. Use this option when you want to include request header values in response
transformations.
base64_encode(string): encodes the input string to base64.
base64_decode(string): decodes the input string from base64.
substring(string, start_pos, substring_len): returns a substring of the
input string, starting at start_pos and extending for substring_len
characters. If no substring_len is provided or substring_len is <= 0, the
substring extends to the end of the input string.
Map of key name -> template to render into the JSON body. Specified keys which don’t exist in the JSON body will be set, keys which do exist will be overriden. For example, given the following JSON body: { “key1”: “value1” } and the following MergeJsonKeys: { “key1”: “{{ header(“header1”) }}”, “key2”: “{{ header(“header2”) }}” } The resulting JSON body will be: { “key1”: “header1_value”, “key2”: “header2_value” }.
If set to true, the template will be set even if the rendered value is empty.
HeaderBodyTransform
"addRequestMetadata": bool
Field
Type
Description
addRequestMetadata
bool
When transforming a request, setting this to true will additionally add “queryString”, “queryStringParameters”, “multiValueQueryStringParameters”, “httpMethod”, “path”, and “multiValueHeaders” to the body.