Cassette: Cassette handler

In ropenscilabs/vcr: Record 'HTTP' Calls to Disk

Cassette handler

Description

Main R6 class that is called from the main user facing function use_cassette()

Value

an object of class Cassette

Points of webmockr integration

• initialize(): webmockr is used in the initialize() method to create webmockr stubs. stubs are created on call to Cassette$new() within insert_cassette(), but then on exiting use_cassette(), or calling eject() on Cassette class from insert_cassette(), stubs are cleaned up.

• eject() method: webmockr::disable() is called before exiting eject to disable webmock so that webmockr does not affect any HTTP requests that happen afterwards

• call_block() method: call_block is used in the use_cassette() function to evaluate whatever code is passed to it; within call_block webmockr::webmockr_allow_net_connect() is run before we evaluate the code block to allow real HTTP requests, then webmockr::webmockr_disable_net_connect() is called after evalulating the code block to disallow real HTTP requests

• make_http_interaction() method: webmockr::pluck_body() utility function is used to pull the request body out of the HTTP request

• serialize_to_crul() method: method: webmockr::RequestSignature and webmockr::Response are used to build a request and response, respectively, then passed to webmockr::build_crul_response() to make a complete crul HTTP response object

Public fields

name

(character) cassette name

record

(character) record mode

manfile

(character) cassette file path

recorded_at

(character) date/time recorded at

serialize_with

(character) serializer to use (yaml|json)

serializer

(character) serializer to use (yaml|json)

persist_with

(character) persister to use (FileSystem only)

persister

(character) persister to use (FileSystem only)

match_requests_on

(character) matchers to use default: method & uri

re_record_interval

(numeric) the re-record interval

tag

ignored, not used right now

tags

ignored, not used right now

root_dir

root dir, gathered from vcr_configuration()

update_content_length_header

(logical) Whether to overwrite the Content-Length header

allow_playback_repeats

(logical) Whether to allow a single HTTP interaction to be played back multiple times

allow_unused_http_interactions

(logical) ignored, not used right now

exclusive

(logical) ignored, not used right now

preserve_exact_body_bytes

(logical) Whether to base64 encode the bytes of the requests and responses

args

(list) internal use

http_interactions_

(list) internal use

new_recorded_interactions

(list) internal use

clean_outdated_http_interactions

(logical) Should outdated interactions be recorded back to file

to_return

(logical) internal use

cassette_opts

(list) various cassette options

Methods

Public methods

• Cassette$new()

• Cassette$print()

• Cassette$call_block()

• Cassette$eject()

• Cassette$file()

• Cassette$recording()

• Cassette$is_empty()

• Cassette$originally_recorded_at()

• Cassette$serializable_hash()

• Cassette$interactions_to_record()

• Cassette$merged_interactions()

• Cassette$up_to_date_interactions()

• Cassette$should_re_record()

• Cassette$should_stub_requests()

• Cassette$should_remove_matching_existing_interactions()

• Cassette$storage_key()

• Cassette$raw_cassette_bytes()

• Cassette$make_dir()

• Cassette$deserialized_hash()

• Cassette$previously_recorded_interactions()

• Cassette$write_recorded_interactions_to_disk()

• Cassette$record_http_interaction()

• Cassette$any_new_recorded_interactions()

• Cassette$make_args()

• Cassette$write_metadata()

• Cassette$http_interactions()

• Cassette$make_http_interaction()

• Cassette$serialize_to_crul()

• Cassette$clone()

---

Method new()

Create a new Cassette object

Usage

Cassette$new(
  name,
  record,
  serialize_with,
  persist_with,
  match_requests_on,
  re_record_interval,
  tag,
  tags,
  update_content_length_header,
  allow_playback_repeats,
  allow_unused_http_interactions,
  exclusive,
  preserve_exact_body_bytes,
  clean_outdated_http_interactions
)

Arguments

name

The name of the cassette. vcr will sanitize this to ensure it is a valid file name.

record

The record mode. Default: "once". In the future we'll support "once", "all", "none", "new_episodes". See recording for more information

serialize_with

(character) Which serializer to use. Valid values are "yaml" (default), the only one supported for now.

persist_with

(character) Which cassette persister to use. Default: "file_system". You can also register and use a custom persister.

match_requests_on

List of request matchers to use to determine what recorded HTTP interaction to replay. Defaults to ⁠["method", "uri"]⁠. The built-in matchers are "method", "uri", "headers" and "body" ("host" and "path" not supported yet, but should be in a future version)

re_record_interval

(numeric) When given, the cassette will be re-recorded at the given interval, in seconds.

tag, tags

tags ignored, not used right now

update_content_length_header

(logical) Whether or not to overwrite the Content-Length header of the responses to match the length of the response body. Default: FALSE

allow_playback_repeats

(logical) Whether or not to allow a single HTTP interaction to be played back multiple times. Default: FALSE.

allow_unused_http_interactions

(logical) ignored, not used right now

exclusive

(logical) ignored, not used right now

preserve_exact_body_bytes

(logical) Whether or not to base64 encode the bytes of the requests and responses for this cassette when serializing it. See also preserve_exact_body_bytes in vcr_configure(). Default: FALSE

clean_outdated_http_interactions

(logical) Should outdated interactions be recorded back to file. Default: FALSE

Returns

A new Cassette object

---

Method print()

print method for Cassette objects

Usage

Cassette$print(x, ...)

Arguments

x

self

...

ignored

---

Method call_block()

run code

Usage

Cassette$call_block(...)

Arguments

...

pass in things to be evaluated

Returns

various

---

Method eject()

ejects the current cassette

Usage

Cassette$eject()

Returns

self

---

Method file()

get the file path for the cassette

Usage

Cassette$file()

Returns

character

---

Method recording()

is the cassette in recording mode?

Usage

Cassette$recording()

Returns

logical

---

Method is_empty()

is the cassette on disk empty

Usage

Cassette$is_empty()

Returns

logical

---

Method originally_recorded_at()

timestamp the cassette was originally recorded at

Usage

Cassette$originally_recorded_at()

Returns

POSIXct date

---

Method serializable_hash()

Get a list of the http interactions to record + recorded_with

Usage

Cassette$serializable_hash()

Returns

list

---

Method interactions_to_record()

Get the list of http interactions to record

Usage

Cassette$interactions_to_record()

Returns

list

---

Method merged_interactions()

Get interactions to record

Usage

Cassette$merged_interactions()

Returns

list

---

Method up_to_date_interactions()

Cleans out any old interactions based on the re_record_interval and clean_outdated_http_interactions settings

Usage

Cassette$up_to_date_interactions(interactions)

Arguments

interactions

list of http interactions, of class HTTPInteraction

Returns

list of interactions to record

---

Method should_re_record()

Should re-record interactions?

Usage

Cassette$should_re_record()

Returns

logical

---

Method should_stub_requests()

Is record mode NOT "all"?

Usage

Cassette$should_stub_requests()

Returns

logical

---

Method should_remove_matching_existing_interactions()

Is record mode "all"?

Usage

Cassette$should_remove_matching_existing_interactions()

Returns

logical

---

Method storage_key()

Get the serializer path

Usage

Cassette$storage_key()

Returns

character

---

Method raw_cassette_bytes()

Get character string of entire cassette; bytes is a misnomer

Usage

Cassette$raw_cassette_bytes()

Returns

character

---

Method make_dir()

Create the directory that holds the cassettes, if not present

Usage

Cassette$make_dir()

Returns

no return; creates a directory recursively, if missing

---

Method deserialized_hash()

get http interactions from the cassette via the serializer

Usage

Cassette$deserialized_hash()

Returns

list

---

Method previously_recorded_interactions()

get all previously recorded interactions

Usage

Cassette$previously_recorded_interactions()

Returns

list

---

Method write_recorded_interactions_to_disk()

write recorded interactions to disk

Usage

Cassette$write_recorded_interactions_to_disk()

Returns

nothing returned

---

Method record_http_interaction()

record an http interaction (doesn't write to disk)

Usage

Cassette$record_http_interaction(x)

Arguments

x

an crul or httr response object, with the request at ⁠$request⁠

Returns

nothing returned

---

Method any_new_recorded_interactions()

Are there any new recorded interactions?

Usage

Cassette$any_new_recorded_interactions()

Returns

logical

---

Method make_args()

make list of all options

Usage

Cassette$make_args()

Returns

nothing returned

---

Method write_metadata()

write metadata to the cassette

Usage

Cassette$write_metadata()

Returns

nothing returned

---

Method http_interactions()

make HTTPInteractionList object, assign to http_interactions_ var

Usage

Cassette$http_interactions()

Returns

nothing returned

---

Method make_http_interaction()

Make an HTTPInteraction object

Usage

Cassette$make_http_interaction(x)

Arguments

x

an crul or httr response object, with the request at ⁠$request⁠

Returns

an object of class HTTPInteraction

---

Method serialize_to_crul()

Make a crul response object

Usage

Cassette$serialize_to_crul()

Returns

a crul response

---

Method clone()

The objects of this class are cloneable with this method.

Usage

Cassette$clone(deep = FALSE)

Arguments

deep

Whether to make a deep clone.

See Also

vcr_configure(), use_cassette(), insert_cassette()

Examples

## Not run: 
library(vcr)
vcr_configure(dir = tempdir())

res <- Cassette$new(name = "bob")
res$file()
res$originally_recorded_at()
res$recording()
res$serializable_hash()
res$eject()
res$should_remove_matching_existing_interactions()
res$storage_key()
res$match_requests_on

# record all requests
res <- Cassette$new("foobar", record = "all")
res$eject()

# cleanup
unlink(file.path(tempdir(), c("bob.yml", "foobar.yml")))

library(vcr)
vcr_configure(dir = tempdir())
res <- Cassette$new(name = "jane")
library(crul)
# HttpClient$new("https://hb.opencpu.org")$get("get")

## End(Not run)

ropenscilabs/vcr documentation built on Feb. 5, 2024, 5:58 p.m.