Added Databricks CLI & Azure CLI authentication and a basic integration test

.github/workflows/acceptance.yaml

 } 
 is_azure <- function() { 
   grepl(".azuredatabricks.net", cfg$host) 
 } 
 # is_gcp returns true if client is configured for GCP 
 is_gcp <- function() { 
   grepl(".gcp.databricks.com", cfg$host) 
 } 
 # is_aws returns true if client is configured for AWS 
 is_aws <- function() { 
   !is_azure() & !is_gcp() 
 } 
@@ -0,0 +1,48 @@
+name: acceptance
+
+on:
+  pull_request:
+    types: [opened, synchronize]
+
+permissions:
+  id-token: write
+  contents: read
+  pull-requests: write
+
+jobs:
+  integration:
+    if: github.event_name == 'pull_request'
+    environment: admin
+    runs-on: larger
+    steps:
+      - name: Checkout Code
+        uses: actions/checkout@v2.5.0
+
+      - name: Unshallow
+        run: git fetch --prune --unshallow
+
+      - uses: actions/checkout@v3
+
+      - uses: r-lib/actions/setup-r@v2
+        with:
+          r-version: release
+          use-public-rspm: true
+
+      - uses: azure/login@v1
+        with:
+          client-id: ${{ secrets.ARM_CLIENT_ID }}
+          tenant-id: ${{ secrets.ARM_TENANT_ID }}
+          allow-no-subscriptions: true
+
+      - uses: r-lib/actions/setup-r-dependencies@v2
+        with:
+          extra-packages: devtools
+          env:
+          R_COMPILE_AND_INSTALL_PACKAGES: never
+
+      - name: Run tests
+        run: Rscript -e "devtools::test()"
+        env:
+          CLOUD_ENV: "${{ vars.CLOUD_ENV }}"
+          DATABRICKS_HOST: "${{ secrets.DATABRICKS_HOST }}"
+

R/api_client.R

@@ -86,10 +86,11 @@ DatabricksClient <- function(profile = NULL, host = NULL, token = NULL, config_f
 
   # cfg is the current unified authentication config of direct parameters,
   # environment variables, and values loaded from ~/.databrickscfg file
-  cfg <- list(host = coalesce(host, Sys.getenv("DATABRICKS_HOST"), from_cli$host),
-    token = coalesce(token, Sys.getenv("DATABRICKS_TOKEN"), from_cli$token),
-    client_id = coalesce(Sys.getenv("DATABRICKS_CLIENT_ID"), from_cli$client_id),
-    client_secret = coalesce(Sys.getenv("DATABRICKS_CLIENT_SECRET"), from_cli$client_secret))
+  cfg <- new.env()
+  cfg$host = coalesce(host, from_cli$host, Sys.getenv("DATABRICKS_HOST"))
+  cfg$token = coalesce(token, from_cli$token, Sys.getenv("DATABRICKS_TOKEN"))
+  cfg$client_id = coalesce(from_cli$client_id, Sys.getenv("DATABRICKS_CLIENT_ID"))
+  cfg$client_secret = coalesce(from_cli$client_secret, Sys.getenv("DATABRICKS_CLIENT_SECRET"))
 
   # add the missing https:// prefix to bare, ODBC-style hosts
   if (!is.null(cfg$host) && !startsWith(cfg$host, "http")) {
@@ -105,7 +106,7 @@ DatabricksClient <- function(profile = NULL, host = NULL, token = NULL, config_f
     used <- c()
     sensitive <- c("token", "password", "client_secret", "google_credentials",
       "azure_client_secret")
-    for (attr in names(cfg)) {
+    for (attr in sort(names(cfg))) {
       value <- cfg[[attr]]
       if (is.null(value)) {
         next
@@ -140,6 +141,32 @@ DatabricksClient <- function(profile = NULL, host = NULL, token = NULL, config_f
     return(function() {
       c(Authentication = paste("Bearer", cfg$token))
     })
+  }, `databricks-cli` = function() {
+    token_source <- .databricks_cli_token_source(cfg)
+    if (is.null(token_source)) {
+      return(NULL)
+    }
+    result <- try(token_source$token(), silent = TRUE)
+    if (inherits(result, "try-error")) {
+      return(NULL)
+    }
+    return(function() {
+      token <- token_source$token()
+      return(token$headers())
+    })
+  }, `azure-cli` = function() {
+    if (!is_azure()) {
+      return(NULL)
+    }
+    token_source <- .azure_cli_token_source("2ff814a6-3304-4ab8-85cb-cd0e6f879c1d")
+    result <- try(token_source$token(), silent = TRUE)
+    if (inherits(result, "try-error")) {
+      return(NULL)
+    }
+    return(function() {
+      token <- token_source$token()
+      return(token$headers())
+    })
   })
 
   # authenticate follows the semantics of Unified Client Authentication and
@@ -212,3 +239,135 @@ DatabricksClient <- function(profile = NULL, host = NULL, token = NULL, config_f
 
   return(list(is_aws = is_aws, is_azure = is_azure, is_gcp = is_gcp, do = do, debug_string = debug_string))
 }
+
+.create_token <- function(access_token, token_type = NULL, expiry = NULL) {
+  if (is.na(expiry)) {
+    expiry <- Sys.time() + as.difftime(300, units = "secs")
+  }
+  state <- new.env()
+  state$access_token <- access_token
+  state$token_type <- token_type
+  state$expiry <- expiry
+  headers <- function() {
+    return(c(Authorization = paste(state$token_type, state$access_token)))
+  }
+  expired <- function() {
+    if (is.null(state$expiry)) {
+      return(FALSE)
+    }
+    # Azure Databricks rejects tokens that expire in 30 seconds or less, so we
+    # refresh the token 40 seconds before it expires.
+    potentially_expired <- state$expiry - as.difftime(40, units = "secs")
+    now <- Sys.time()
+    is_expired <- potentially_expired < now
+    return(is_expired)
+  }
+  valid <- function() {
+    if (is.null(state$access_token)) {
+      return(FALSE)
+    }
+    if (expired()) {
+      return(FALSE)
+    }
+    return(TRUE)
+  }
+  return(list(headers = headers, valid = valid))
+}
+
+.refreshable_token_source <- function(refresh) {
+  state <- new.env()
+  state$token <- NULL
+  # this is not thread-safe, but R is single-threaded
+  return(list(token = function() {
+    tok <- state$token
+    if (!is.null(tok)) {
+      is_valid <- tok$valid()
+      if (is_valid) {
+        return(tok)
+      }
+    }
+    state$token <- refresh()
+    return(state$token)
+  }))
+}
+
+.token_source <- function() {
+  return(list(token = function() {
+    stop("token method must be implemented", call. = FALSE)
+  }))
+}
+
+.cli_token_source <- function(cmd, token_type_field, access_token_field, expiry_field) {
+  parse_expiry <- function(expiry) {
+    formats <- c("%Y-%m-%dT%H:%M:%OS", "%Y-%m-%dT%H:%M:%S")
+    for (fmt in formats) {
+      tryCatch({
+        x <- as.POSIXct(expiry, format = fmt)
+        return(x)
+      }, error = function(e) {
+        # TODO: improve this
+        last_error <<- e
+      })
+    }
+    if (exists("last_error")) {
+      stop(last_error)
+    }
+  }
+  return(.refreshable_token_source(function() {
+    tryCatch({
+      # TODO: do better handling, so that we don't see a warning message, when
+      # Databricks OAuth is not configured for the given host on the given
+      # machine
+      out <- system2(command = cmd, stdout = TRUE, stderr = TRUE)
+      tryCatch({
+        it <- jsonlite::fromJSON(out)
+        expiry <- it[[expiry_field]]
+        expires_on <- parse_expiry(expiry)
+        access_token <- it[[access_token_field]]
+        token_type <- it[[token_type_field]]
+        return(.create_token(access_token, token_type, expires_on))
+      }, error = function(e) {
+        if (inherits(e, "error")) {
+          message <- if (length(e$message) > 0) e$message else ""
+          stop(paste("cannot unmarshal CLI result:", out, message))
+        } else if (inherits(e, "try-error")) {
+          stdout <- if (length(e$message) > 0) e$message else ""
+          stderr <- if (length(e$stderr) > 0) e$stderr else ""
+          message <- if (nchar(stdout) > 0) stdout else stderr
+          stop(paste("cannot get access token:", message))
+        }
+      })
+    }, error = function(e) {
+      stop("cannot execute CLI command:", e)
+    })
+  }))
+}
+
+.databricks_cli_token_source <- function(cfg) {
+  if (is.null(cfg$host)) {
+    return(NULL)
+  }
+  args <- c("auth", "token", "--host", cfg$host)
+  cli_path <- tryCatch({
+    # Try to find 'databricks' in PATH
+    (Sys.which("databricks"))
+  }, error = function(e) {
+    # If 'databricks' is not found, try to find 'databricks.exe'
+    if (Sys.info()["sysname"] == "Windows") {
+      (Sys.which("databricks.exe"))
+    } else {
+      (NULL)
+    }
+  })
+  if (is.null(cli_path)) {
+    return(NULL)
+  }
+  cmd <- c(cli_path, args)
+  return(.cli_token_source(cmd, "token_type", "access_token", "expiry"))
+}
+
+.azure_cli_token_source <- function(resource) {
+  cmd <- c("az", "account", "get-access-token", "--resource", resource, "--output",
+    "json")
+  return(.cli_token_source(cmd, "tokenType", "accessToken", "expiresOn"))
+}

tests/testthat/test_api_client.R

@@ -14,7 +14,7 @@ test_that("loads configuration file", {
 
 test_that("parses configuration profile", {
   client <- databricks:::DatabricksClient(config_file = "./data/awscfg", profile="client-secret")
-  expected <- "host=https://another.cloud.databricks.com/, client_id=xxx, client_secret=***"
+  expected <- "client_id=xxx, client_secret=***, host=https://another.cloud.databricks.com/"
   expect_equal(expected, client$debug_string())
 })
 

tests/testthat/test_current_user.R

@@ -0,0 +1,9 @@
+library(testthat)
+
+skip_if(Sys.getenv("DATABRICKS_HOST") == "", "Not integration test")
+
+test_that("detects current user", {
+  client <- databricks::DatabricksClient()
+  user <- databricks::me(client)
+  expect_false(is.null(user$userName))
+})