Adding support windows stemcells (#9)

* adding windows specific cf files * .bat for running sigsci-agent.ps script * adding to script * -make sure .bat and .ps1 sigsci-agent scripts are copied to the correct locations in supply.ps1 -create health check process from a codeblock -cleanup and more testing * - uncomment upstream hc code - remove unused detect.ps1 - set port env var at the user level to persist value * update README.md * use SIGSCI_AGENT_VERSION if it's set * - use gzip vs zip - remove extra $() Co-authored-by: bbucher-sigsci <[email protected]>
signalsciences · Apr 6, 2021 · 7fe294b · 7fe294b
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diff --git a/README.md b/README.md
@@ -12,6 +12,15 @@ Application developers will need to specify the buildpack with the `cf push` com
 
 `cf push YOUR-APP -b https://github.com/signalsciences/sigsci-cloudfoundry-buildpack.git -b APP_BUILDPACK`
 
+### Windows support
+Support is available for Windows stemcells. Deploying to a windows environment is similar to linux:
+
+`cf push YOUR-APP -s windows -b https://github.com/signalsciences/sigsci-cloudfoundry-buildpack.git -b APP_BUILDPACK`
+
+In almost all cases, it will be used in conjunction with the following  buildpacks:
+* `binary-buildpack:` [binary-buildpack](https://github.com/cloudfoundry/binary-buildpack) - for console apps, .net core, .exe
+* `hwc-buildpack:` [hwc-buildpack](https://github.com/cloudfoundry/hwc-buildpack) - legacy ASP.NET / WCF
+
 ### Configuration
 
 To configure the Signal Sciences agent the following environment variables must be set:

diff --git a/bin/detect.bat b/bin/detect.bat
@@ -0,0 +1,3 @@
+@echo off
+
+exit /b 1
diff --git a/bin/supply.bat b/bin/supply.bat
@@ -0,0 +1,2 @@
+@echo off
+powershell.exe -ExecutionPolicy Unrestricted %~dp0\supply.ps1 %1 %2 %3 %4
diff --git a/bin/supply.ps1 b/bin/supply.ps1
@@ -0,0 +1,23 @@
+Write-Output "-----> SUPPLY Installing signalsciences cloudfoundry scripts"
+
+$buildDir = $args[0]
+$depsDir = $args[2]
+$index = $args[3]
+
+# create the .profile.d dir
+$profileDir = Join-Path $buildDir -ChildPath '.profile.d'
+New-Item -ItemType Directory -Force -Path $profileDir | Out-Null
+
+$rootPath = $PSScriptRoot | Split-Path
+$sigsciPs1Script = (Join-Path $rootPath -ChildPath 'lib' | Join-Path -ChildPath 'sigsci-agent.ps1')
+$sigsciPs1AgentInstallSCript = (Join-Path $depsDir -ChildPath $index | Join-Path -ChildPath 'sigsci-agent.ps1')
+$sigsciBatAgentInstallSCript = (Join-Path $profileDir -ChildPath 'sigsci-agent.bat')
+$sigsciPs1Exe = "%~dp0\..\..\deps\$index\sigsci-agent.ps1"
+
+# create batch file which will execute the powershell script in the dep/$idx dir
+New-Item -ItemType Directory -Force -Path $profileDir | Out-Null
+echo '@echo off' | Out-File -Encoding ASCII "$sigsciBatAgentInstallSCript"
+echo "powershell.exe -ExecutionPolicy Unrestricted -File ""$sigsciPs1Exe""" | Out-File -Append -Encoding ASCII "$sigsciBatAgentInstallSCript"
+
+# copy the sigsci-agent.ps1 script to .profile.d dir
+Copy-Item $sigsciPs1Script -Destination $sigsciPs1AgentInstallSCript
diff --git a/lib/sigsci-agent.bat b/lib/sigsci-agent.bat
@@ -0,0 +1,2 @@
+@echo off
+powershell.exe -ExecutionPolicy Unrestricted %~dp0\sigsci-agent.ps1
diff --git a/lib/sigsci-agent.ps1 b/lib/sigsci-agent.ps1
@@ -0,0 +1,311 @@
+Write-Output "Setting up sigsci agent"
+
+function generate_hc_script {
+    $hc_script = {
+        param(
+            [string[]]$hc_config = @('5','/','502','5','200','3'),
+            [string]$hc_listener_port = "8080",
+            [string]$hc_upstream_port = "8081",
+            [string]$sigsci_dir = "$pwd\.profile.d\sigsci"
+        )
+
+        # assign array values to variables to make reading code easier
+        $hc_frequency = $hc_config[0]
+        $hc_endpoint = $hc_config[1]
+        $hc_listener_kill_on_status = $hc_config[2]
+        $hc_listener_warning = $hc_config[3]
+        $hc_upstream_kill_not_status = $hc_config[4]
+        $hc_upstream_warning = $hc_config[5]
+
+        $listener_warning_count = 0
+        $upstream_warning_count = 0
+
+        # start the agent health check
+        Start-Sleep -s $initial_sleep
+
+        Write-Output "Starting agent health check process"
+
+        while ($true)
+        {
+            Start-Sleep -s $hc_frequency
+            # check the listener process
+            $listener_status = (Invoke-WebRequest -UseBasicParsing -Uri "http://localhost:$hc_listener_port$hc_endpoint" -TimeoutSec 3).StatusCode
+
+            # check the upstream process
+            $upstream_status = (Invoke-WebRequest -UseBasicParsing -Uri "http://localhost:$hc_upstream_port$hc_endpoint" -TimeoutSec 3).StatusCode
+
+            if (($listener_status -eq $hc_listener_kill_on_status) -or (000 -eq $listener_status))
+            {
+                $listener_warning_count++
+
+                if ($listener_warning_count -gt $hc_listener_warning)
+                {
+                    Write-Error "Listener became unhealthy! Killing sigsci-agent.exe process"
+                    Stop-Process -Name "sigsci-agent"
+                    return
+                }
+                else
+                {
+                    Write-Warning "sigsci-agent HC_LISTENER_WARNING at $listener_warning_count out of $hc_listener_warning."
+                }
+            }
+            else
+            {
+                $listener_warning_count = 0
+            }
+
+            # verify upstream status
+            if (($upstream_status -ne $hc_upstream_kill_not_status) -or ( 000 -eq $upstream_status))
+            {
+                $upstream_warning_count++
+
+                if ($upstream_warning_count -gt $hc_upstream_warning)
+                {
+                    Write-Error "Upstream became unhealthy! Killing sigsci-agent.exe process"
+                    Stop-Process -Name "sigsci-agent"
+                    return
+                }
+                else
+                {
+                    Write-Warning "sigsci-agent HC_UPSTREAM_WARNING at $upstream_warning_count out of $hc_upstream_warning."
+                }
+            }
+            else
+            {
+                $upstream_warning_count = 0
+            }
+        }
+    }
+
+    #create hc.ps1 in $sigsci_dir\bin
+    $file = "hc.ps1"
+    $bin_dir = "$sigsci_dir\bin"
+    Try
+    {
+        $hc_script | Out-File -FilePath "$bin_dir\$file" -Width 4096
+        return "$bin_dir\$file"
+    }
+    Catch {
+        Write-Error "There was a problem creating $file in $bin_dir. More Info: $PSItem"
+        Write-Error "The app and agent will still start, but health check functionality will be disabled."
+    }
+    return $null
+}
+
+# check if the PORT envirornment variable is set
+if (-not (Test-Path env:PORT))
+{
+    Write-Output "-----> Cloud Foundry PORT not set and cannot determine configuration. Agent not starting!!!"
+    exit
+}
+
+# check if SIGSCI_ACCESSKEYID and SIGSCI_SECRETACCESSKEY are set before proceeding with agent installation
+if ((Test-Path env:SIGSCI_ACCESSKEYID) -and (Test-Path env:SIGSCI_SECRETACCESSKEY))
+{
+    # setup sigsci agent directories
+    $sigsci_dir = (Join-Path $pwd -ChildPath '.profile.d' | Join-Path -ChildPath 'sigsci')
+    New-Item -ItemType Directory -Force -Path $sigsci_dir\bin | Out-Null
+    New-Item -ItemType Directory -Force -Path $sigsci_dir\conf | Out-Null
+
+    # install sigsci agent
+
+    # if agent version not specified then get the latest version.
+    if (-not (Test-Path env:SIGSCI_AGENT_VERSION))
+    {
+        $sigsci_agent_version = (Invoke-WebRequest -UseBasicParsing -Uri 'https://dl.signalsciences.net/sigsci-agent/VERSION').Content.TrimEnd("`r?`n")
+
+    }
+    else
+    {
+        $sigsci_agent_version = $Env:SIGSCI_AGENT_VERSION
+    }
+
+    # check if $sigsci_agent_version exists
+    $status = (Invoke-WebRequest -UseBasicParsing -Uri "https://dl.signalsciences.net/sigsci-agent/$sigsci_agent_version/VERSION").StatusCode
+
+    if (-not ($status -eq 200))
+    {
+        # skip agent install if $status not 200
+        Write-Error "-----> SigSci Agent version $sigsci_agent_version not found or network unavailable after 90 seconds!"
+        Write-Error "-----> SIGSCI AGENT WILL NOT BE INSTALLED!"
+    } else {
+        Write-Output "-----> Downloading sigsci-agent"
+        Invoke-WebRequest -UseBasicParsing -OutFile "sigsci-agent_$sigsci_agent_version.zip" `
+                -Uri "https://dl.signalsciences.net/sigsci-agent/$sigsci_agent_version/windows/sigsci-agent_$sigsci_agent_version.zip"
+
+        if (-not(Test-Path env:SIGSCI_DISABLE_CHECKSUM_INTEGRITY_CHECK))
+        {
+            # download the .sha256 file
+            Invoke-WebRequest -UseBasicParsing `
+                -OutFile "sigsci-agent_$sigsci_agent_version.zip.sha256" `
+                -Uri "https://dl.signalsciences.net/sigsci-agent/$sigsci_agent_version/windows/sigsci-agent_$sigsci_agent_version.zip.sha256"
+
+            # compute hash and verify against .sha256
+            $computed_hash = (Get-FileHash -Algorithm SHA256 "./sigsci-agent_$sigsci_agent_version.zip").Hash
+            $hash = Select-String -Path "./sigsci-agent_$sigsci_agent_version.zip.sha256" -Pattern  $computed_hash -Quiet
+            if (-not (Select-String -Path "./sigsci-agent_$sigsci_agent_version.zip.sha256" -Pattern $computed_hash -Quiet))
+            {
+                Write-Error "-----> sigsci-agent not installed because checksum integrity check failed"
+                exit 1
+            }
+        }
+
+        Expand-Archive -Path "sigsci-agent_$sigsci_agent_version.zip" -DestinationPath $sigsci_dir\bin
+        Write-Output "-----> Finished installing sigsci-agent"
+
+        # configure the agent
+        $port_listener = $Env:PORT
+        $port_upstream = 8081
+        $sigsci_upstream = "0.0.0.0:$port_upstream"
+        $sigsci_config_file = "$sigsci_dir\conf\agent.conf"
+
+        # optional config environment variables, if not provided default value will be used.
+
+        # reverse proxy upstream
+        if (-not(Test-Path env:SIGSCI_REVERSE_PROXY_UPSTREAM))
+        {
+            Write-Output "-----> SIGSCI_REVERSE_PROXY_UPSTREAM not provided, using default: $sigsci_upstream"
+        }
+        else
+        {
+            $sigsci_upstream = $Env:SIGSCI_REVERSE_PROXY_UPSTREAM
+            $port_upstream = $sigsci_upstream.split(':')[1]
+        }
+
+        # reverse proxy accesslog - disable access logging by default.
+        if (-not(Test-Path env:SIGSCI_REVERSE_PROXY_ACCESSLOG))
+        {
+            $sigsci_reverse_proxy_accesslog = 'access.log'
+        }
+        else
+        {
+            $sigsci_reverse_proxy_accesslog = $Env:SIGSCI_REVERSE_PROXY_ACCESSLOG
+        }
+
+        # require signal sciences agent for app to start.
+        # this prevent port reassignment in the event the agent fails to start.
+        # as a result, cloud foundry will detect the app as unhealthy.
+        # default is to not require the agent.
+        if (-not(Test-Path env:SIGSCI_REQUIRED))
+        {
+            $sigsci_required = $false
+        }
+        else
+        {
+            $sigsci_required = $false
+
+            if ($Env:SIGSCI_REQUIRED -eq "true") {
+                $sigsci_required = $true
+            }
+        }
+
+        # health check - disable by default.
+        if (-not(Test-Path env:SIGSCI_HC))
+        {
+            $sigsci_hc = $false
+        }
+        else
+        {
+            $sigsci_hc = $false
+
+            if ($Env:SIGSCI_HC -eq "true") {
+                $sigsci_hc = $true
+            }
+        }
+
+        # health check - initial sleep.
+        if (-not(Test-Path env:SIGSCI_HC_INIT_SLEEP))
+        {
+            $sigsci_hc_init_sleep = 30
+        }
+        else
+        {
+            $sigsci_hc_init_sleep = [int]$Env:SIGSCI_HC_INIT_SLEEP
+        }
+
+        # health check config
+        #
+        # HC_CONFIG fields:
+        # <frequency>:<endpoint>:<listener status>:<listener warning>:<upstream status>:<upstream warning>
+        #
+        # frequency - how often to perform the check in seconds, e.g. every 5 seconds.
+        # endpoint - which endpoint to check for both the listener and upstream process.
+        # listener status - the status code that not healthy and will trigger killing the agent.
+        # listener warning - the number of times the check can fail before killing the agent.
+        # upstream status = the status code that is healthy, any other code will trigger killing the agent.
+        # upstream warning - the number of times the check can fail before killing the agent.
+        #
+        # Note: the listener port is defined by the PORT_LISTENER variable.
+        # Note: the upstream port is defined by the PORT_UPSTREAM variable.
+        # Note: the PID to kill is defined by the SIGSCI_PID variable.
+        if (Test-Path env:SIGSCI_HC_CONFIG)
+        {
+            $sigsci_hc_config = "$Env:SIGSCI_HC_CONFIG".split(":")
+
+        }
+
+        # reassign PORT for application process.
+        # NOTE: It seems like setting an env var at the user level explicitly is the only way to persist it beyond
+        #       the script's session.
+        [System.Environment]::SetEnvironmentVariable('PORT', $port_upstream,[System.EnvironmentVariableTarget]::User)
+
+        $sigsci_config = @"
+server-flavor="sigsci-module-cloudfoundry"
+# Signal Sciences Reverse Proxy Config
+[revproxy-listener.http]
+listener="http://0.0.0.0:$($port_listener)"
+upstreams="http://$sigsci_upstream"
+access-log="$($sigsci_reverse_proxy_accesslog)"
+"@
+
+        $sigsci_config -f 'string' | Out-File $sigsci_config_file -Encoding ascii
+
+        # start the agent
+        Write-Output "-----> Starting Signal Sciences Agent!"
+
+        Start-Process $sigsci_dir\bin\sigsci-agent.exe --config="$sigsci_config_file" `
+            -WorkingDirectory "$sigsci_dir\bin" -WindowStyle Hidden -PassThru
+
+        # wait for agent to start
+        Start-Sleep -s 5
+
+        # Check if agent is running. If not, reassign port so app can start.
+        if (-not(Get-Process sigsci-agent))
+        {
+            if ($sigsci_required)
+            {
+                Write-Error "-----> Signal Sciences failed to start!"
+                Write-Error "-----> SIGSCI_REQUIRED is enabled, port reassignment will not occur and app will be unhealthy!!!"
+            } else {
+                [System.Environment]::SetEnvironmentVariable('PORT', $port_listener,[System.EnvironmentVariableTarget]::User)
+                Write-Error "-----> Signal Sciences failed to start!"
+                Write-Error "-----> Deploying application without Signal Sciences enabled!!!"
+            }
+        } else {
+            if ($sigsci_hc)
+            {
+                Write-Output "-----> sigsci-agent health checks enabled. Health checks will start in $sigsci_hc_init_sleep seconds."
+
+                # generate the health check script
+                $script = generate_hc_script
+
+                if ($script -ne $null)
+                {
+                    # start the agent health check process
+                    Start-Process powershell.exe -ArgumentList "-file $script" -WorkingDirectory "$sigsci_dir\bin" -WindowStyle Hidden -PassThru `
+                    -RedirectStandardError ".\hc-stderr.out" -RedirectStandardOutput ".\hc-stdout.log"
+                }
+                else {
+                    Write-Error "generate_hc_script returned null. Health checks are not running"
+                }
+            }
+        }
+    }
+}
+else
+{
+    Write-Output "-----> Signal Sciences access keys not set. Agent not starting!!!"
+    Write-Output "-----> To enable the Signal Sciences agent please set the following environment variables:"
+    Write-Output "-----> SIGSCI_ACCESSKEYID"
+    Write-Output "-----> SIGSCI_SECRETACCESSKEY"
+}