plumber 1.1.0

Breaking changes

  • Force json serialization of endpoint error responses instead of using endpoint serializer. (@meztez, #689)

  • When plumbing a Plumber file and using a Plumber router modifier (#* @plumber), an error will be thrown if the original router is not returned. (#738)

  • options_plumber() now requires that all options are named. If no option name is provided, an error with be thrown. (#746)

New features

  • Added option plumber.trailingSlash. This option (which is disabled by default) allows routes to be redirected to route definitions with a trailing slash. For example, if a GET request is submitted to /test?a=1 with no /test route is defined, but a GET /test/ route definition does exist, then the original request will respond with a 307 to reattempt against GET /test/?a=1. This option will be enabled by default in a future release. This logic executed for before calling the 404 handler. (#746)

  • Added an experimental option plumber.methodNotAllowed. This option (which is enabled by default) allows for a status of 405 to be returned if an invalid method is used when requesting a valid route. This logic executed for before calling the default 404 handler. (#746)

  • Passing edit = TRUE to plumb_api() will open the API source file. (#699)

  • OpenAPI Specification can be set using a file path. (@meztez #696)

  • Guess OpenAPI response content type from serializer. (@meztez #684)

  • Undeprecated Plumber$run(debug=, swaggerCallback=) and added the parameters for Plumber$run(docs=, quiet=) and pr_run(debug=, docs=, swaggerCallback=, quiet=). Now, all four parameters will not produce lingering effects on the Plumber router. (@jcheng5 #765)

    • Setting quiet = TRUE will suppress routine startup messages.
    • Setting debug = TRUE, will display information when an error occurs. See pr_set_debug().
    • Setting docs will update the visual documentation. See pr_set_docs().
    • Set swaggerCallback to a function which will be called with a url to the documentation, or NULL to do nothing. See pr_set_docs_callback().
  • To update a PlumberEndpoint path after initialization, call the new PlumberEndpoint$setPath(path). This will update internal path matching meta data. (Active bindings were not used to avoid breaking changes.) (@blairj09 #770)

  • Allow for spaces in @apiTag and @tag when tag is surrounded by single or double quotes. (#685)

Bug fixes

  • Ignore regular comments in block parsing. (@meztez #718)

  • Block parsing comments, tags and responses ordering match plumber api ordering. (#722)

  • Fixed bug where httpuv would return a status of 500 with body An exception occurred if no headers were set on the response object. (#745)

  • Fixed bug where all pr_*() returned invisibly. Now all pr_*() methods will print the router if displayed in the console. (#740)

  • When calling Plumber$handle() and defining a new PlumberEndpoint, ... will be checked for invalid names. (@meztez, #677)

  • /__swagger__/ now always redirects to /__docs__/, even when Swagger isn’t the selected interface. Use options(plumber.legacyRedirects = FALSE) to disable this behavior. (@blairj09 #694)

  • Fixed available_apis() bug where all packages printed all available APIs. (@meztez #708)

  • Fixed Plumber $routes resolution bugs. Routes are now returned in lexicographical order. (@meztez #702)

  • Plumber will now display a circular reference if one is found while printing. (#738)

  • Changed future::plan() from multiprocess to multisession in example API 14-future as “Strategy ‘multiprocess’ is deprecated in future (>= 1.20.0)”. (#747)

  • Setting options to NULL will also set deprecated but supported option plumber.swagger.url. (#766)

plumber 1.0.0

New features

Plumber router

  • Added support for promises in endpoints, filters, and hooks. This allows for multi-core execution when paired with future. See plumb_api("plumber", "13-promises") and plumb_api("plumber", "14-future") for example implementations. (#248)

  • Added a Tidy API for more natural usage with magrittr’s %>%. For example, a plumber object can now be initiated and run with pr() %>% pr_run(port = 8080). For more examples, see here (@blairj09, #590)

  • Added support for #' @plumber tag to gain programmatic access to the plumber router via function(pr) {....}. See system.file("plumber/06-sessions/plumber.R", package = "plumber") and how it adds cookie support from within plumber.R. (@meztez and @blairj09, #568)

  • Added plumb_api() for standardizing where to locate (inst/plumber) and how to run (plumb_api(package, name)) plumber apis inside an R package. To view the available Plumber APIs, call available_apis(). (#631)

  • Improved argument handling in Plumber Endpoint route definitions. See system.file("plumber/17-arguments/plumber.R", package = "plumber") to view an example with expected output and plumb_api("plumber", "17-arguments") to retrieve the api. Improvements include:

    • The value supplied to req and res arguments in a route definition are now always Plumber request and response objects. In the past, this was not guaranteed. (#666, #637)
    • To assist with conflicts in argument names deriving from different locations, req$argsQuery, req$argsPath, and req$argsBody have been added to access query, path, and req$body parameters, respectively. For this reason, we suggest defining routes with only req and res (i.e., function(req, res) {}) and accessing argument(s) under these new fields to avoid naming conflicts. (#637)
    • An error is no longer thrown if multiple arguments are matched to an Plumber Endpoint route definition. Instead, Plumber now retains the first named argument according to the highest priority match (req$argsQuery is 1st priority, then req$argsPath, then req$argsBody). (#666)
    • Unnamed elements that are added to req$args by filters or creating req$argsBody will no longer throw an error. They will only be passed through via ... (#666)


  • API Documentation is now hosted at /__docs__. If swagger documentation is being used, /__swagger__ will redirect to /__docs__. (#654)

  • Added OpenAPI support for array parameters using syntax name:[type] and new type list (synonym df, data.frame). (@meztez, #532)

  • Added user provided OpenAPI Specification handler to Plumber router. Use $setApiSpec() to provide a function to alter the Plumber generated OpenAPI Specification returned by Plumber router method $getApiSpec(). This also affects /openapi.json and /openapi.yaml (#365)(@meztez, #562)

  • Added validate_api_spec() to validate a Plumber API produces a valid OpenAPI Specification. (Experimental!) (#633)


Body parsing

Visual Documentation

Security improvements

  • Secret session cookies are now encrypted using sodium. All prior req$session information will be lost. Please see ?session_cookie for more information. (#404)

  • Session cookies set the HttpOnly flag by default to mitigate cross-site scripting (XSS). Please see ?session_cookie for more information. (#404)

  • Wrap jsonlite::fromJSON to ensure that jsonlite never reads input as a remote address (such as a file path or URL) and attempts to parse that. The only known way to exploit this behavior in plumber unless an API were using encrypted cookies and an attacker knew the encryption key in order to craft arbitrary cookies. (#325)

Breaking changes

  • When plumb()ing a file (or Plumber$new(file)), the working directory is set to the file’s directory before parsing the file. When running the Plumber API, the working directory will be set to file’s directory before running.(#631)

  • Plumber’s OpenAPI Specification is now defined using OpenAPI 3, upgrading from Swagger Specification. (#365)

  • Plumber router $run() method arguments swagger, swaggerCallback and debug are now deprecated. User interface and url callback are now enabled by default and managed through Plumber router $setDocs(), $setDocsCallback(), and $setDebug() methods and options and (@meztez, #562)

  • plumb() now returns an object of class "Plumber" (previously "plumber"). To check if an object is a Plumber router, use new method is_plumber(). (#653)

  • PlumberStatic objects now have a class of "PlumberStatic" (previously "plumberstatic"). (#653)

  • The source files used in plumber must use the UTF-8 encoding if they contain non-ASCII characters (@shrektan, #312,


  • options(plumber.debug) is not set anymore when running the plumber application. Instead retrieve the debug value using $getDebug() on the Plumber router directly. Ex: function(req, res) { req$pr$getDebug() }. (#639)

  • PlumberEndpoint’s method $exec() now has a shape of $exec(req, res) (vs $exec(...)). This allows for fine tune control over the arguments being sent to the endpoint function.

  • When creating a PlumberFilter or PlumberEndpoint, an error will be thrown if expr does not evaluate to a function. (#666)


  • Shorthand serializers are now deprecated. @html, @json, @png, @jpeg, @svg should be replaced with the @serializer syntax. Ex: @serializer html or @serializer jpeg (#630)

  • plumber R6 object has been deprecated and renamed to Plumber. PlumberStatic’s inherited class has been updated to Plumber. (#653)

  • hookable R6 object has been deprecated and renamed to Hookable. Plumber and PlumberStep’s inherited class has been updated to Hookable. (#653)

  • addSerializer() has been deprecated in favor of register_serializer() (#584)

  • getCharacterSet() has been deprecated in favor of get_character_set() (#651)

  • randomCookieKey() has been deprecated in favor of random_cookie_key() (#651)

  • sessionCookie() has been deprecated in favor of session_cookie() (#651)

  • DigitalOcean helper functions are now defunct (do_*()). The functionality and documentation on how to deploy to DigitalOcean has been moved to plumberDeploy (by @meztez) (#649)

Minor new features and improvements

  • Documentation is updated and now presented using pkgdown (#570)

  • New hex logo! Thank you @allisonhorst ! (#570)

  • Added helper method is_plumber(pr) to determine if an object is a Plumber router. (#653)

  • Added support for the SameSite Cookie attribute. (@chris-dudley, #640)

  • When calling include_file(), the content_type is automatically inferred from the file extension if content_type is not provided. (#631)

  • When plumb()ing a file, arguments supplied to parsers and serializers may be values defined earlier in the file. (@meztez, #620)

  • Updated Docker files. New Docker repo is now rstudio/plumber. Updates heavily inspired from @mskyttner (#459). (#589)

  • Support HTTP 405 Code. (@meztez, #554)

  • Attached the Plumber router to the incoming request object at req$pr. (@meztez, #554)

  • Documented plumber options. Added options_plumber(). (@meztez, #555)

  • Update documentation on R6 objects (@meztez, #530)

  • Fix plumb() function when plumb()ing a directory so that plumber.R is not a requirement if a valid entrypoint.R file is found. (@blairj09, #471).

  • If cookie information is too large (> 4093 bytes), a warning will be displayed. (#404)

  • Added new shorthand types for url parameters. (@byzheng, #388)

  • Plumber files are now only evaluated once. Prior plumber behavior sourced endpoint functions twice and non-endpoint code blocks once. (#328)

  • Improve speed of canServe() method of the PlumberEndpoint class (@atheriel, #484)

  • Get more file extension content types using the mime package. (#660)

  • Endpoints that produce images within a promises::promise() will now use the expected graphics device. (#669)

Bug fixes

  • Handle plus signs in URI as space characters instead of actual plus signs (@meztez, #618)

  • Paths that are missing a leading / have a / prepended to the path location. (#656)

  • Fix possible bugs due to mounted routers without leading slashes (@atheriel, #476 #501).

  • Modified images serialization to use content-type serializer. Fixes issue with images pre/postserialize hooks (@meztez, #518).

  • Fix bug preventing error handling when a serializer fails (@antoine-sachet, #490)

  • Fix URL-decoding of query parameters and URL-encoding/decoding of cookies. Both now use httpuv::decodeURIComponent instead of httpuv::decodeURI. (@antoine-sachet, #462)

  • Fixed bug where functions defined earlier in the file could not be found when plumb()ing a file. (#416)

  • A multiline request body is now collapsed to a single line (@robertdj, #270 #297).

  • Bumped version of httpuv to >= to address an unexpected segfault (@shapenaji, #289)

  • Date response header is now supplied by httpuv and not plumber. Fixes non standard date response header issues when using different locales. (@shrektan, #319, #380)

  • Due to incompatibilities with multipart body values, req$postBody will only be calculated if accessed. It is strongly recommended to use req$bodyRaw when trying to create content from the input body. (#665)

plumber 0.4.6

  • BUGFIX: Hooks that accept a value argument (postroute, preserialize, and postserialize) now modify the incoming value as documented.
  • BUGFIX: The postserialize hook is now given the serialized data as its value parameter.
  • BUGFIX: properly handle cookie expiration values (#216).
  • Add support for tags in Swagger docs (#230).
  • Optional swaggerCallback parameter for run() to supply a callback function for reporting the url for swagger page.
  • Add RStudio Project Template to package.

plumber 0.4.4

  • Support Expiration, HTTPOnly, and Secure flags on cookies (#87). EDIT: see #216 which prevented expiration from working.
  • BUGFIX: properly handle named query string and post body arguments in mounted subrouters.
  • Added support for static sizing of images. @png and @jpeg now accept a parenthetical list of arguments that will be passed into the png() or jpeg() call. This enables annotations like #' @png (width = 200, height=500).
  • Enable ByteCompile flag
  • Set working directory for DigitalOcean APIs.
  • Respect setErrorHandler
  • BUGFIX: export PlumberStatic
  • Case-insensitive matching on plumber.r and entrypoint.r when plumb()ing a directory.
  • Support query strings with keys that appear more than once (#165)
  • Fix the validation error warning at the bottom of deployed Swagger files which would have appeared any time your swagger.json file was hosted in such a way that a hosted validator service would not have been able to access it. For now we just suppress validation of swagger.json files. (#149)
  • Support for floating IPs in DNS check that occurs in do_configure_https()
  • Make adding swap file idempotent in do_provision() so you can now call that on a single droplet multiple times.
  • Support an exit hook which can define a function that will be evaluated when the API is interrupted. e.g. pr <- plumb("plumber.R"); pr$registerHook("exit", function(){ print("Bye bye!") })
  • Fixed bug in which a single function couldn’t support multiple paths for a single verb (#203).
  • Support negative numbers in numeric path segments (#212)
  • Support . in string path segments

plumber 0.4.2

  • Development version for 0.4.2. Will be working to move to even/odd release cycles, but I had prematurely bumped to 0.4.0 so that one might get skipped, making the next CRAN release 0.4.2.

plumber 0.4.0

  • BREAKING: Listen on localhost instead of listening publicly by default.
  • BREAKING: We no longer set the Access-Control-Allow-Origin HTTP header to *. This was previously done for convenience but we’ve decided to prioritize security here by removing this default. You can still add this header to any route you want to be accessible from other origins.
  • BREAKING: Listen on a random port by default instead of always on 8000. This can be controlled using the port parameter in run(), or by setting the plumber.port option.
  • BREAKING: Removed PlumberProcessor class and replaced with a notion of hooks. See registerHook and registerHooks on the Plumber router.
  • BREAKING: addGlobalProcessor method on Plumber routers now takes a list which are added as hooks instead of a Processor. Note that sessionCookie has also been updated to behave accordingly, meaning that the convention of pr$addGlobalProcessor(sessionCookie("secret", "cookieName")) will continue to work for this release.
  • BREAKING: sessionCookie now returns a list instead of a Processor. Note that addGlobalProcessor has also been updated to behave accordingly, meaning that the convention of pr$addGlobalProcessor(sessionCookie("secret", "cookieName")) will continue to work for this release.
  • DEPRECATION: Deprecated the addAssets method on Plumber routers. Use PlumberStatic and the mount method to attach a static router.
  • DEPRECATION: Deprecated the addEndpoint method in favor of the handle method for Plumber routers. Removed support for the processors, params, and comments parameters are no longer supported.
  • DEPRECATION: Deprecated the addFilter method on Plumber routers in favor of the new filter method. Removed support for the processor parameter.
  • DEPRECATION: Deprecated the addGlobalProcessor method on Plumber routers.
  • The undocumented setDefaultErrorHandler method on Plumber routers now takes a function that returns the error handler function. The top-level function takes a single param named debug which is managed by the debug parameter in the run() method.
  • Added support for OPTIONS HTTP requests via the @options annotation.
  • Add support for entrypoint.R when plumb()ing a directory. If this file exists, it is expected to return a Plumber router representing the API contained in this directory. If it doesn’t exist, the behavior is unaltered. If both plumber.R and entrypoint.R exist, entrypoint.R takes precedence.
  • plumb() the current directory by default if no arguments are provided.
  • Added a debug parameter to the run method which can be set to TRUE in order to get more insight into your API errors.

plumber 0.3.3

  • plumb() now accepts an argument dir, referring to a directory containing plumber.R, which may be provided instead of file.

plumber 0.3.2

  • Introduced the do_provision(), do_deploy_api(), do_remove_api() and do_configure_https() functions to provision and manage your APIs on a cloud server running on DigitalOcean.
  • source() the referenced R file to plumb inside of a new environment that inherits directly from the GlobalEnv. This provides more explicit control over exactly how this environment should behave.
  • Added @serializer htmlwidget to support rendering and returning a self-contained htmlwidget from a plumber endpoint.
  • Properly handle cookies with no value. (#88)
  • Don’t convert + character in a query string to a space.

plumber 0.3.1

  • Add a method to consume JSON on post (you can still send a query string in the body of a POST request as well).

plumber 0.3.0

  • BREAKING CHANGE: serializer factories are now registered instead of the serializer themselves. Thus, addSerializer() now expects a function that returns a serializer, and Response$new() now expects a serializer itself rather than a character string naming a serializer. Internally it is the serializer itself that is attached to the response rather than the name of the serializer. This allows for a serializer to customize its behavior.
  • Accept an additional argument on the @serializer annotation – R code that will be passed in as an argument to the serializer factory. See example 09-content-type.

plumber 0.2.4

  • Add a filter which parses and sets req$cookies to be a list corresponding to the cookies provided with the request.
  • Responses can set multiple cookies
  • Bug Fix: convert non-character arguments in setCookie to character before URL- encoding.

plumber 0.2.3

  • Set options(warn=1) during execution of user code so that warnings are immediately visible in the console, rather than storing them until the server is stopped.

plumber 0.2.2

  • Add sessionCookie function to define a processor that can be used as a globalProcessor on a router to encrypt values from req$session and store them as an encrypted cookie in on the user’s browser.
  • Added setCookie method to response which (primitively) allows you to set a cookie to be included in the response.
  • Add addGlobalProcessor method on plumber class to support a processor that runs a processor only a single time, before and then after all other filters and the endpoint.
  • Document all public params so CHECK passes

plumber 0.2.1

  • Add more roxygen2 documentation for exported functions
  • Remove the warning in the README as the API seems to be stabilizing.

plumber 0.2.0

  • BREAKING: Changed variable-path routing to use bracketed format instead of just a colon.
  • BREAKING: Renamed PlumberRouter R6 object to just Plumber.
  • Support addEndpoint() and addFilter() on the Plumber object.
  • Added support for the #* prefix.

plumber 0.1.0

  • Initial Release