fc init

.gitignore

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+### VisualStudioCode template
+.vscode/*
+!.vscode/settings.json
+!.vscode/tasks.json
+!.vscode/launch.json
+!.vscode/extensions.json
+*.code-workspace
+
+# Local History for Visual Studio Code
+.history/
+
+### JetBrains template
+# Covers JetBrains IDEs: IntelliJ, RubyMine, PhpStorm, AppCode, PyCharm, CLion, Android Studio, WebStorm and Rider
+# Reference: https://intellij-support.jetbrains.com/hc/en-us/articles/206544839
+
+# User-specific stuff
+.idea/**/workspace.xml
+.idea/**/tasks.xml
+.idea/**/usage.statistics.xml
+.idea/**/dictionaries
+.idea/**/shelf
+
+# Generated files
+.idea/**/contentModel.xml
+
+# Sensitive or high-churn files
+.idea/**/dataSources/
+.idea/**/dataSources.ids
+.idea/**/dataSources.local.xml
+.idea/**/sqlDataSources.xml
+.idea/**/dynamic.xml
+.idea/**/uiDesigner.xml
+.idea/**/dbnavigator.xml
+
+# Gradle
+.idea/**/gradle.xml
+.idea/**/libraries
+
+# Gradle and Maven with auto-import
+# When using Gradle or Maven with auto-import, you should exclude module files,
+# since they will be recreated, and may cause churn.  Uncomment if using
+# auto-import.
+# .idea/artifacts
+# .idea/compiler.xml
+# .idea/jarRepositories.xml
+# .idea/modules.xml
+# .idea/*.iml
+# .idea/modules
+# *.iml
+# *.ipr
+
+# CMake
+cmake-build-*/
+
+# Mongo Explorer plugin
+.idea/**/mongoSettings.xml
+
+# File-based project format
+*.iws
+
+# IntelliJ
+out/
+
+# mpeltonen/sbt-idea plugin
+.idea_modules/
+
+# JIRA plugin
+atlassian-ide-plugin.xml
+
+# Cursive Clojure plugin
+.idea/replstate.xml
+
+# Crashlytics plugin (for Android Studio and IntelliJ)
+com_crashlytics_export_strings.xml
+crashlytics.properties
+crashlytics-build.properties
+fabric.properties
+
+# Editor-based Rest Client
+.idea/httpRequests
+
+# Android studio 3.1+ serialized cache file
+.idea/caches/build_file_checksums.ser
+
+### Go template
+# Binaries for programs and plugins
+*.exe
+*.exe~
+*.dll
+*.so
+*.dylib
+
+# Test binary, built with `go test -c`
+*.test
+
+# Output of the go coverage tool, specifically when used with LiteIDE
+*.out
+
+# Dependency directories (remove the comment below to include it)
+# vendor/
+
+coverage.txt

Makefile

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+# This Makefile is meant to be used by people that do not usually work
+# with Go source code. If you know what GOPATH is then you probably
+# don't need to bother with make.
+
+.PHONY: all clean test
+GOBIN = build/bin
+OS = $(shell uname)
+ifeq ($(OS), Linux)
+endif
+
+ifeq ($(OS), Darwin)
+endif
+
+format:
+	find . -name '*.go' -type f -not -path "./vendor*" -not -path "*.git*" -not -path "*/generated/*" | xargs gofmt -w -s
+test:
+	go test ./... -v -race -cpu=1,2,4 -coverprofile=coverage.txt -covermode=atomic -benchmem -bench .

README.md

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+# filecache
+## a simple file cache of Golang
+
+## Overview
+
+A file cache can be created with either the `NewDefaultCache()` function to
+get a cache with the defaults set, or `NewCache()` to get a new cache with
+`0` values for everything; you will not be able to store items in this cache
+until the values are changed; specifically, at a minimum, you should set
+the `MaxItems` field to be > 0.
+
+Let's start with a basic example; we'll create a basic cache and give it a
+maximum item size of 128M:
+
+```
+cache := filecache.NewDefaultCache()
+cache.MaxSize = 128 * filecache.Megabyte
+cache.Start()
+```
+
+The `Kilobyte`, `Megabyte`, and `Gigabyte` constants are provided as a
+convience when setting cache sizes.
+
+When `cache.Start()` is called, a goroutine is launched in the background
+that routinely checks the cache for expired items. The delay between
+runs is specified as the number of seconds given by `cache.Every` ("every
+`cache.Every` seconds, check for expired items"). There are three criteria
+used to determine whether an item in the cache should be expired; they are:
+
+   1. Has the file been modified on disk? (The cache stores the last time
+      of modification at the time of caching, and compares that to the
+      file's current last modification time).
+   2. Has the file been in the cache for longer than the maximum allowed
+      time?
+   3. Is the cache at capacity? When a file is being cached, a check is
+      made to see if the cache is currently filled. If it is, the item that
+      was last accessed the longest ago is expired and the new item takes
+      its place. When loading items asynchronously, this check might miss
+      the fact that the cache will be at capacity; the background scanner
+      performs a check after its regular checks to ensure that the cache is
+      not at capacity.
+
+The background scanner can be disabled by setting `cache.Every` to 0; if so,
+cache expiration is only done when the cache is at capacity.
+
+Once the cache is no longer needed, a call to `cache.Stop()` will close down
+the channels and signal the background scanner that it should stop.
+
+
+## Usage
+
+### Initialisation and Startup
+
+The public fields of the `FileCache` struct are:
+
+```
+    MaxItems   int   // Maximum number of files to cache
+    MaxSize    int64 // Maximum file size to store
+    ExpireItem int   // Seconds a file should be cached for
+    Every      int   // Run an expiration check Every seconds
+```
+
+You can create a new file cache with one of two functions:
+
+* `NewCache()`: creates a new bare repository that just has the underlying
+cache structure initialised. The public fields are all set to `0`, which is
+very likely not useful (at a minimum, a `MaxItems` of `0` means no items can
+or will be stored in the cache).
+* `NewDefaultCache()` returns a new file cache initialised to some basic
+defaults. The defaults are:
+
+```
+	DefaultExpireItem int   = 300 // 5 minutes
+	DefaultMaxSize    int64 =  4 * Megabyte
+	DefaultMaxItems   int   = 32
+	DefaultEvery      int   = 60 // 1 minute
+```
+
+These defaults are public variables, and you may change them to more useful
+values to your program.
+
+Once the cache has been initialised, it needs to be started using the
+`Start()` method. This is important for initialising the goroutine responsible
+for ensuring the cache remains updated, as well as setting up the asynchronous
+caching goroutine. The `Active` method returns true if the cache is currently
+running. `Start()` returns an `error` if an error occurs; if one is returned,
+the cache should not be used.