1 files changed, 75 insertions, 0 deletions
diff --git a/src/update_database.nim b/src/update_database.nim
new file mode 100644
index 0000000..1a27517
--- /dev/null
+++ b/src/update_database.nim
@@ -0,0 +1,75 @@
+import json
+import os
+import osproc
+import parsecfg
+import strformat
+import strutils
+
+type
+    CgiError = object of CatchableError
+        code: int
+
+proc newCgiError(code: int, message: string): ref CgiError =
+    result = newException(CgiError, message)
+    result.code = code
+
+proc readData(): string =
+    var size = parseInt(getEnv("CONTENT_LENGTH").string)
+    if size == 0:
+        return ""
+    result = newString(size)
+    if readBuffer(stdin, addr result[0], size) != 0:
+        raise newCgiError(400, "not enough data")
+
+proc main() =
+    if paramCount() != 2:
+        raise newCgiError(500, "one argument required")
+
+    let config = loadConfig(paramStr(1))
+    let databaseDir = config.getSectionValue("", "databaseDir")
+    if databaseDir == "":
+        raise newCgiError(500, "databaseDir is empty")
+
+    if getEnv("REQUEST_METHOD") != "POST":
+        raise newCgiError(400, "request method must be POST")
+
+    let j = parseJson(readData())
+
+    for alias, measurement in j:
+        let filename = normalizedPath(joinPath(databaseDir, alias & ".rrd"))
+
+        if not filename.startsWith(databaseDir):
+            raise newCgiError(400, "invalid database")
+        let
+            timestamp = measurement["timestamp"].getBiggestInt()
+            temperature = measurement["temperature"].getFloat()
+            humidity = measurement["humidity"].getFloat()
+            pressure = measurement["pressure"].getFloat()
+            battery = measurement["battery_potential"].getFloat()
+            data = &"{timestamp}:{temperature}:{humidity}:{pressure}:{battery}"
+            (_, ec) = execCmdEx(&"rrdtool update {filename} {data}")
+        if ec != 0:
+            raise newCgiError(500, "rrdtool failed")
+
+try:
+    main()
+    echo("Content-Type: text/plain")
+    echo("")
+except CgiError as e:
+    echo(&"Status: {e.code}")
+    echo("Content-Type: text/plain")
+    echo("")
+    echo(e.msg)
+    quit(0)
+except JsonParsingError as e:
+    echo(&"Status: 400 Bad Request")
+    echo("Content-Type: text/plain")
+    echo("")
+    echo(&"invalid json: {e.msg}")
+    quit(0)
+except Exception as e:
+    echo(&"Status: 500 Internal Server Error")
+    echo("Content-Type: text/plain")
+    echo("")
+    echo(e.msg)
+    quit(0)