All functions are located in the com.biffweb namespace.

(pprint & args)
Alias of clojure.pprint/pprint


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(start-system init)
Deprecated. See Biff v0.7.3 release notes.

Starts a system from an initial system map.

Stores the system in the com.biffweb/system atom. Returns the contents of the
atom. See https://biffweb.com/docs/reference/system-composition
Deprecated. See Biff v0.7.3 release notes.

Stops the system, refreshes source files, and restarts the system.

The system is stopped by calling all the functions in (:biff/stop
@com.biffweb/system). (:biff/after-refresh @system) is a fully-qualified
symbol which will be resolved and called after refreshing. See


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(use-config {:keys [biff/config], :or {config "config.edn"}, :as ctx})
Reads config from an edn file and merges into ctx.

The config file's contents should be a map from environments to config keys
and values, for example:

{:prod {:host "example.com"
        :port 8080}
 :dev {:merge [:prod]
       :host "localhost"}}

The current environment should be stored in the BIFF_ENV environment variable.
The default value is `prod`. To inherit config from other environments, set
:merge to a sequence of environment keys.
(sh & args)
Runs a shell command.

Returns the output if successful; otherwise, throws an exception.


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(assoc-some m & kvs)
Like assoc, but skips kv pairs where the value is nil.
(pred-> x pred f)
Convenience fn for (cond-> x (pred x) f)
(join sep xs)
Returns a sequence where the elements of coll are separated by sep.


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(safe-merge & ms)
Like merge, but throws an exception if any maps share keys.


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(normalize-email email)
Normalizes an email address to make future lookups easier.

Trims leading and trailing whitespace and converts to lower case. Returns nil
if the email is empty after trimming.


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(use-when f & components)
Passes the system map to components only if (f system) is true.

See https://biffweb.com/docs/reference/system-composition
(sha256 string)
Returns the SHA256 hash of string.


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(base64-encode bytes)
Converts a byte array to a base64 string.


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(base64-decode string)
Converts a base64 string to a byte array.


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(anomaly? x)
Returns true if x is an anomaly.

See https://github.com/cognitect-labs/anomalies
(anom category & [message & [opts]])
Constructs an anomaly.

Example: (anom :incorrect
               "Invalid parameter"
               {:info "x should be an integer"})

See https://github.com/cognitect-labs/anomalies


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(select-ns-as m ns-from ns-to)
Selects and renames keys from m based on the namespace.


(select-ns-as {:foo/a 1, :foo.bar/b 2, :baz/c 3} 'foo 'quux)
=> {:quux/a 1, :quux.bar/b 2}

(select-ns-as {:foo/a 1, :foo.bar/b 2, :baz/c 3} 'foo nil)
=> {:a 1, :bar/b 2}


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(catchall & body)
Wraps body in (try ... (catch Exception _ nil))


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(catchall-verbose & body)
Like catchall, but prints exceptions.
(letd bindings & body)
Like let, but transparently wraps all bindings with delay.


(macroexpand-1 '(letd [a 1]
=> (let [a (delay 1)]

(letd [a (do (println "a evaluated")
       {:keys [b]} (do (println "b evaluated")
                       {:b 2})
       [_ _ c] (do (println "c evaluated")
                   [1 2 3])]
  (if (even? b)
(out) b evaluated
(out) a evaluated


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(fix-print & body)
Ensures that print output doesn't get swallowed by e.g. an editor nrepl plugin.

Binds *out*, *err* and *flush-on-newline* to their root values.

  (println "hello"))


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(eval-files! {:keys [biff/eval-paths], :or {eval-paths ["src"]}})
Evaluates any modified files and their dependents via clojure.tools.namespace.


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Loads new dependencies in deps.edn via tools.deps.alpha.

Ensures that a DynamicClassLoader is available so that this works even when
not evaluated from the repl. See


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 {:keys [dir exts age-seconds], :or {age-seconds 30}, :as opts})
Deletes files descended from the given directory that are older than a given threshold.

dir:          A path to a directory.
age-seconds:  Files will only be deleted if it's been at least this number of seconds since they
              were last modified. Defaults to 30 seconds.
exts:         An optional collection of filename extentions. If provided, files will only be
              deleted if they end with one of the extentions.

For example:
(delete-old-files {:dir "target/resources/public"
                   :exts [".html"]})


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 {:keys [biff/secret],
  :biff.s3/keys [origin access-key bucket key method headers body],
  :as ctx}
 {:as opts})
Makes a request to an S3-compatible service.

- `key` will be coerced to a string.
- `body` can be a string or a file.
- `headers` is a map. When putting an object, it should at least contain the
  keys "content-type" and "x-amz-acl".
- Common values for the "x-amz-acl" header include "public-read" and
- Any keys in `opts` will be prepended with the biff.s3 namespace and merged
  into `ctx`.
- Your S3 secret key should be accessible with (secret :biff.s3/secret-key).
- Public files will be available at "<edge URL>/<key>", for example,


# secrets.env

;; config.edn
{:prod {:biff.s3/origin "https://nyc3.digitaloceanspaces.com"
        :biff.s3/access-key "your-access-key"
        :biff.s3/secret-key "S3_SECRET_KEY"
        :biff.s3/bucket "default-bucket"

;; Put an object:
(s3-request ctx {:method "PUT"
                 :key "some-key"
                 :body "some-body"
                 :headers {"x-amz-acl" "private"
                           "content-type" "text/plain"}})

;; Get an object:
(:body (s3-request ctx {:method "GET"
                        :key "some-key"}))
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