@@ -0,0 +1,738 @@ 
+import 
+  asynchttpserver,
+  asyncdispatch,
+  strutils,
+  sequtils,
+  cgi,
+  strtabs,
+  pegs,
+  json,
+  os,
+  times
+import 
+  types,
+  contenttypes,
+  core,
+  utils,
+  logger
+
+# Helper procs
+
+proc sqlOp(op: string): string =
+  let table = newStringTable()
+  table["not eq"] = "<>"
+  table["eq"] = "=="
+  table["gt"] = ">"
+  table["gte"] = ">="
+  table["lt"] = "<"
+  table["lte"] = "<="
+  table["contains"] = "contains"
+  return table[op]
+
+proc orderByClauses*(str: string): string =
+  var clauses = newSeq[string]()
+  var fragments = str.split(",")
+  let clause = peg"""
+    clause <- {[-+]} {field}
+    field <- ('id' / 'created' / 'modified' / path)
+    path <- '$' (objField)+
+    ident <- [a-zA-Z0-9_]+
+    objField <- '.' ident
+  """
+  for f in fragments:
+    var matches = @["", ""]
+    if f.find(clause, matches) != -1:
+      var field = matches[1]
+      if field[0] == '$':
+        field = "json_extract(documents.data, '$1')" % matches[1]
+      if matches[0] == "-":
+        clauses.add("$1 DESC" % field)
+      else:
+        clauses.add("$1 ASC" % field)
+  return clauses.join(", ")
+
+proc selectClause*(str: string, options: var QueryOptions) = 
+  let tokens = """
+    path <- '$' (objItem / objField)+
+    ident <- [a-zA-Z0-9_]+
+    objIndex <- '[' \d+ ']'
+    objField <- '.' ident
+    objItem <- objField objIndex
+  """
+  let fields = peg("""
+    fields <- ^{field} (\s* ',' \s* {field})*$
+    field <- path \s+ ('as' / 'AS') \s+ ident 
+  """ & tokens)
+  let field = peg("""
+    field <- ^{path} \s+ ('as' / 'AS') \s+ {ident}$ 
+  """ & tokens)
+  var fieldMatches = newSeq[string](10)
+  if str.strip.match(fields, fieldMatches):
+    for m in fieldMatches:
+      if m.len > 0:
+        var rawTuple = newSeq[string](2)
+        if m.match(field, rawTuple):
+          options.jsonSelect.add((path: rawTuple[0], alias: rawTuple[1]))
+
+proc filterClauses*(str: string, options: var QueryOptions) = 
+  let tokens = """
+    operator <- 'not eq' / 'eq' / 'gte' / 'gt' / 'lte' / 'lt' / 'contains'
+    value <- string / number / 'null' / 'true' / 'false'
+    string <- '"' ('\"' . / [^"])* '"'
+    number <- '-'? '0' / [1-9] [0-9]* ('.' [0-9]+)? (( 'e' / 'E' ) ( '+' / '-' )? [0-9]+)?
+    path <- '$' (objItem / objField)+
+    ident <- [a-zA-Z0-9_]+
+    objIndex <- '[' \d+ ']'
+    objField <- '.' ident
+    objItem <- objField objIndex
+  """
+  let clause = peg("""
+    clause <- {path} \s+ {operator} \s+ {value}
+  """ & tokens)
+  let andClauses = peg("""
+    andClauses <- ^{clause} (\s+ 'and' \s+ {clause})*$
+    clause <- path \s+ operator \s+ value
+  """ & tokens)
+  let orClauses = peg("""
+    orClauses <- ^{andClauses} (\s+ 'or' \s+ {andClauses})*$
+    andClauses <- clause (\s+ 'and' \s+ clause)*
+    clause <- path \s+ operator \s+ value
+  """ & tokens)
+  var orClausesMatches = newSeq[string](10)
+  discard str.strip.match(orClauses, orClausesMatches)
+  var parsedClauses = newSeq[seq[seq[string]]]()
+  for orClause in orClausesMatches:
+    if orClause.len > 0:
+      var andClausesMatches = newSeq[string](10)
+      discard orClause.strip.match(andClauses, andClausesMatches)
+      var parsedAndClauses = newSeq[seq[string]]()
+      for andClause in andClausesMatches:
+        if andClause.len > 0:
+          var clauses = newSeq[string](3)
+          discard andClause.strip.match(clause, clauses)
+          clauses[1] = sqlOp(clauses[1])
+          if clauses[2] == "true":
+            clauses[2] = "1"
+          elif clauses[2] == "false":
+            clauses[2] = "0"
+          parsedAndClauses.add clauses
+      if parsedAndClauses.len > 0:
+        parsedClauses.add parsedAndClauses
+  if parsedClauses.len == 0:
+    return
+  var currentArr = 0
+  var tables = newSeq[string]()
+  let resOrClauses = parsedClauses.map do (it: seq[seq[string]]) -> string:
+    let resAndClauses = it.map do (x: seq[string]) -> string:
+      if x[1] == "contains":
+        currentArr = currentArr + 1
+        tables.add "json_each(documents.data, '$1') AS arr$2" % [x[0], $currentArr]
+        return "arr$1.value == $2" % [$currentArr, x[2]]
+      else:
+        return "json_extract(documents.data, '$1') $2 $3" % x
+    return resAndClauses.join(" AND ")
+  options.tables = options.tables & tables
+  options.jsonFilter = resOrClauses.join(" OR ")
+
+proc parseQueryOption*(fragment: string, options: var QueryOptions) =
+  if fragment == "":
+    return
+  var pair = fragment.split('=')
+  if pair.len < 2 or pair[1] == "":
+    raise newException(EInvalidRequest, "Invalid query string fragment '$1'" % fragment)
+  try:
+    pair[1] = pair[1].replace("+", "%2B").decodeURL
+  except:
+    raise newException(EInvalidRequest, "Unable to decode query string fragment '$1'" % fragment)
+  case pair[0]:
+    of "filter":
+      filterClauses(pair[1], options)
+      if options.jsonFilter == "":
+        raise newException(EInvalidRequest, "Invalid filter clause: $1" % pair[1].replace("\"", "\\\""))
+    of "select":
+      selectClause(pair[1], options)
+      if options.jsonSelect.len == 0:
+        raise newException(EInvalidRequest, "Invalid select clause: $1" % pair[1].replace("\"", "\\\""))
+    of "like":
+      options.like = pair[1]
+    of "search":
+      options.search = pair[1]
+    of "tags":
+      options.tags = pair[1]
+    of "limit":
+      try:
+        options.limit = pair[1].parseInt
+      except:
+        raise newException(EInvalidRequest, "Invalid limit value: $1" % getCurrentExceptionMsg())
+    of "offset":
+      try:
+        options.offset = pair[1].parseInt
+      except:
+        raise newException(EInvalidRequest, "Invalid offset value: $1" % getCurrentExceptionMsg())
+    of "sort":
+      let orderby = pair[1].orderByClauses()
+      if orderby != "":
+        options.orderby = orderby
+      else:
+        raise newException(EInvalidRequest, "Invalid sort value: $1" % pair[1])
+    else:
+      return
+
+proc parseQueryOptions*(querystring: string, options: var QueryOptions) =
+  var fragments = querystring.split('&')
+  for f in fragments:
+    f.parseQueryOption(options)
+
+proc validate*(req: LSRequest, LS: LiteStore, resource: string, id: string, cb: proc(req: LSRequest, LS: LiteStore, resource: string, id: string):LSResponse): LSResponse = 
+  if req.reqMethod == HttpPost or req.reqMethod == HttpPut or req.reqMethod == HttpPatch:
+    var ct =  ""
+    let body = req.body.strip
+    if body == "":
+      return resError(Http400, "Bad request: No content specified for document.")
+    if req.headers.hasKey("Content-Type"):
+      ct = req.headers["Content-Type"]
+      case ct:
+        of "application/json":
+          try:
+            discard body.parseJson()
+          except:
+            return resError(Http400, "Invalid JSON content - $1" % getCurrentExceptionMsg())
+        else:
+          discard
+  return cb(req, LS, resource, id)
+
+proc patchTag(tags: var seq[string], index: int, op, path, value: string): bool =
+  LOG.debug("- PATCH -> $1 tag['$2'] = \"$3\" - Total tags: $4." % [op, $index, $value, $tags.len])
+  case op:
+    of "remove":
+      let tag = tags[index]
+      if not tag.startsWith("$"):
+        tags[index] = "" # Not removing element, otherwise subsequent indexes won't work!
+      else:
+        raise newException(EInvalidRequest, "cannot remove system tag: $1" % tag)
+    of "add":
+      if value.match(PEG_USER_TAG):
+        tags.insert(value, index)
+      else:
+        if value.strip == "":
+          raise newException(EInvalidRequest, "tag not specified." % value)
+        else:
+          raise newException(EInvalidRequest, "invalid tag: $1" % value)
+    of "replace":
+      if value.match(PEG_USER_TAG):
+        if tags[index].startsWith("$"):
+          raise newException(EInvalidRequest, "cannot replace system tag: $1" % tags[index])
+        else:
+          tags[index] = value
+      else:
+        if value.strip == "":
+          raise newException(EInvalidRequest, "tag not specified." % value)
+        else:
+          raise newException(EInvalidRequest, "invalid tag: $1" % value)
+    of "test":
+      if tags[index] != value:
+        return false
+    else:
+      raise newException(EInvalidRequest, "invalid patch operation: $1" % op)
+  return true
+
+proc patchData*(data: var JsonNode, origData: JsonNode, op: string, path: string, value: JsonNode): bool =
+  LOG.debug("- PATCH -> $1 path $2 with $3" % [op, path, $value])
+  var keys = path.replace(peg"^\/data\/", "").split("/")
+  if keys.len == 0:
+    raise newException(EInvalidRequest, "no valid path specified: $1" % path)
+  var d = data
+  var dorig = origData
+  var c = 1
+  for key in keys:
+    if d.kind == JArray:
+      try:
+        var index = key.parseInt
+        if c >= keys.len:
+          d.elems[index] = value
+          case op:
+            of "remove":
+              d.elems.del(index)
+            of "add": 
+              d.elems.insert(value, index)
+            of "replace": 
+              d.elems[index] = value
+            of "test": 
+              if d.elems[index] != value:
+                return false
+            else:
+              raise newException(EInvalidRequest, "invalid patch operation: $1" % op)
+        else:
+          d = d[index]
+          dorig = dorig[index]
+      except:
+        raise newException(EInvalidRequest, "invalid index key '$1' in path '$2'" % [key, path])
+    else:
+      if c >= keys.len:
+        case op:
+          of "remove":
+            if d.hasKey(key):
+              d.delete(key)
+            else:
+              raise newException(EInvalidRequest, "key '$1' not found in path '$2'" % [key, path])
+          of "add": 
+            d[key] = value
+          of "replace": 
+            if d.hasKey(key):
+              d[key] = value
+            else:
+              raise newException(EInvalidRequest, "key '$1' not found in path '$2'" % [key, path])
+          of "test": 
+            if dorig.hasKey(key):
+              if dorig[key] != value:
+                return false
+            else:
+              raise newException(EInvalidRequest, "key '$1' not found in path '$2'" % [key, path])
+          else:
+            raise newException(EInvalidRequest, "invalid patch operation: $1" % op)
+      else:
+        d = d[key]
+        dorig = dorig[key]
+    c += 1
+  return true
+
+
+proc applyPatchOperation*(data: var JsonNode, origData: JsonNode, tags: var seq[string], op: string, path: string, value: JsonNode): bool =
+  var matches = @[""]
+  let p = peg"""
+    path <- ^tagPath / fieldPath$
+    tagPath <- '\/tags\/' {\d+}
+    fieldPath <- '\/data\/' ident ('\/' ident)*
+    ident <- [a-zA-Z0-9_]+ / '-'
+  """
+  if path.find(p, matches) == -1:
+    raise newException(EInvalidRequest, "cannot patch path '$1'" % path)
+  if path.match(peg"^\/tags\/"):
+    let index = matches[0].parseInt
+    if value.kind != JString:
+      raise newException(EInvalidRequest, "tag '$1' is not a string." % $value)
+    let tag = value.getStr
+    return patchTag(tags, index, op, path, tag)
+  elif tags.contains("$subtype:json"):
+    return patchData(data, origData, op, path, value)
+  else:
+    raise newException(EInvalidRequest, "cannot patch data of a non-JSON document.")
+
+# Low level procs
+
+proc getTag*(LS: LiteStore, id: string, options = newQueryOptions()): LSResponse =
+  let doc = LS.store.retrieveTag(id, options)
+  result.headers = ctJsonHeader()
+  if doc == newJObject():
+    result = resTagNotFound(id)
+  else:
+    result.content = $doc
+    result.code = Http200
+
+proc getRawDocument*(LS: LiteStore, id: string, options = newQueryOptions()): LSResponse =
+  let doc = LS.store.retrieveRawDocument(id, options)
+  result.headers = ctJsonHeader()
+  if doc == "":
+    result = resDocumentNotFound(id)
+  else:
+    result.content = doc
+    result.code = Http200
+
+proc getDocument*(LS: LiteStore, id: string, options = newQueryOptions()): LSResponse =
+  let doc = LS.store.retrieveDocument(id, options)
+  if doc.data == "":
+    result = resDocumentNotFound(id)
+  else:
+    result.headers = doc.contenttype.ctHeader
+    result.content = doc.data
+    result.code = Http200
+
+proc deleteDocument*(LS: LiteStore, id: string): LSResponse =
+  let doc = LS.store.retrieveDocument(id)
+  if doc.data == "":
+    result = resDocumentNotFound(id)
+  else:
+    try:
+      let res = LS.store.destroyDocument(id)
+      if res == 0:
+        result = resError(Http500, "Unable to delete document '$1'" % id)
+      else:
+        result.headers = newHttpHeaders(TAB_HEADERS)
+        result.headers["Content-Length"] = "0"
+        result.content = ""
+        result.code = Http204
+    except:
+      result = resError(Http500, "Unable to delete document '$1'" % id)
+
+proc getTags*(LS: LiteStore, options: QueryOptions = newQueryOptions()): LSResponse =
+  var options = options
+  let t0 = cpuTime()
+  let docs = LS.store.retrieveTags(options)
+  let orig_limit = options.limit
+  let orig_offset = options.offset
+  options.limit = 0
+  options.offset = 0
+  options.select = @["COUNT(tag_id)"]
+  let total = LS.store.countTags(prepareSelectTagsQuery(options), options.like.replace("*", "%"))
+  var content = newJObject()
+  if options.like != "":
+    content["like"] = %(options.like.decodeURL)
+  if orig_limit > 0:
+    content["limit"] = %orig_limit
+    if orig_offset > 0:
+      content["offset"] = %orig_offset
+  content["total"] = %total
+  content["execution_time"] = %(cputime()-t0)
+  content["results"] = docs
+  result.headers = ctJsonHeader()
+  result.content = content.pretty
+  result.code = Http200
+
+proc getRawDocuments*(LS: LiteStore, options: QueryOptions = newQueryOptions()): LSResponse =
+  var options = options
+  let t0 = cpuTime()
+  let docs = LS.store.retrieveRawDocuments(options)
+  let orig_limit = options.limit
+  let orig_offset = options.offset
+  options.limit = 0
+  options.offset = 0
+  options.select = @["COUNT(docid)"]
+  let total = LS.store.retrieveRawDocuments(options)[0].num
+  var content = newJObject()
+  if options.folder != "":
+    content["folder"] = %(options.folder)
+  if options.search != "":
+    content["search"] = %(options.search.decodeURL)
+  if options.tags != "":
+    content["tags"] = newJArray()
+    for tag in options.tags.replace("+", "%2B").decodeURL.split(","):
+      content["tags"].add(%tag)
+  if orig_limit > 0:
+    content["limit"] = %orig_limit
+    if orig_offset > 0:
+      content["offset"] = %orig_offset
+  if options.orderby != "":
+    content["sort"] = %options.orderby
+  content["total"] = %total
+  content["execution_time"] = %(cputime()-t0)
+  content["results"] = docs
+  result.headers = ctJsonHeader()
+  result.content = content.pretty
+  result.code = Http200
+
+proc getInfo*(LS: LiteStore): LSResponse =
+  let info = LS.store.retrieveInfo()
+  let version = info[0]
+  let total_documents = info[1]
+  let total_tags = LS.store.countTags()
+  let tags = LS.store.retrieveTagsWithTotals()
+  var content = newJObject()
+  content["version"] = %(LS.appname & " v" & LS.appversion)
+  content["datastore_version"] = %version
+  content["size"] = %($((LS.file.getFileSize().float/(1024*1024)).formatFloat(ffDecimal, 2)) & " MB")
+  content["read_only"] = %LS.readonly
+  content["log_level"] = %LS.loglevel
+  if LS.directory.len == 0: 
+    content["directory"] = newJNull()
+  else: 
+    content["directory"] = %LS.directory 
+  content["mount"] = %LS.mount
+  content["total_documents"] = %total_documents
+  content["total_tags"] = %total_tags
+  content["tags"] = tags
+  result.headers = ctJsonHeader()
+  result.content = content.pretty
+  result.code = Http200
+
+proc postDocument*(LS: LiteStore, body: string, ct: string, folder=""): LSResponse =
+  if not folder.isFolder:
+    return resError(Http400, "Invalid folder specified when creating document: $1" % folder) 
+  try:
+    var doc = LS.store.createDocument(folder, body, ct)
+    if doc != "":
+      result.headers = ctJsonHeader()
+      result.content = doc
+      result.code = Http201
+    else:
+      result = resError(Http500, "Unable to create document.")
+  except:
+    result = resError(Http500, "Unable to create document.")
+
+proc putDocument*(LS: LiteStore, id: string, body: string, ct: string): LSResponse =
+  if id.isFolder:
+    return resError(Http400, "Invalid ID '$1' (Document IDs cannot end with '/')." % id)
+  let doc = LS.store.retrieveDocument(id)
+  if doc.data == "":
+    # Create a new document
+    var doc = LS.store.createDocument(id, body, ct)
+    if doc != "":
+      result.headers = ctJsonHeader()
+      result.content = doc
+      result.code = Http201
+    else:
+      result = resError(Http500, "Unable to create document.")
+  else:
+    # Update existing document
+    try:
+      var doc = LS.store.updateDocument(id, body, ct)
+      if doc != "":
+        result.headers = ctJsonHeader()
+        result.content = doc
+        result.code = Http200
+      else:
+        result = resError(Http500, "Unable to update document '$1'." % id)
+    except:
+      result = resError(Http500, "Unable to update document '$1'." % id)
+
+proc patchDocument*(LS: LiteStore, id: string, body: string): LSResponse =
+  var apply = true
+  let jbody = body.parseJson
+  if jbody.kind != JArray:
+    return resError(Http400, "Bad request: PATCH request body is not an array.")
+  var options = newQueryOptions()
+  options.select = @["documents.id AS id", "created", "modified", "data"]
+  let doc = LS.store.retrieveRawDocument(id, options)
+  if doc == "":
+    return resDocumentNotFound(id)
+  let jdoc = doc.parseJson
+  var tags = newSeq[string]()
+  var origTags = newSeq[string]()
+  for tag in jdoc["tags"].items:
+    tags.add(tag.str)
+    origTags.add(tag.str)
+  var data: JsonNode
+  var origData: JsonNode
+  if tags.contains("$subtype:json"):
+    try:
+      origData = jdoc["data"].getStr.parseJson
+      data = origData.copy
+    except:
+      discard
+  var c = 1
+  for item in jbody.items:
+    if item.hasKey("op") and item.hasKey("path"):
+      if not item.hasKey("value"):
+        item["value"] = %""
+      try:
+        apply = applyPatchOperation(data, origData, tags, item["op"].str, item["path"].str, item["value"])
+        if not apply:
+          break
+      except:
+        return resError(Http400, "Bad request - $1" % getCurrentExceptionMsg())
+    else:
+        return resError(Http400, "Bad request: patch operation #$1 is malformed." % $c)
+    c.inc
+  if apply:
+    if origData.len > 0 and origData != data:
+      try:
+        var doc = LS.store.updateDocument(id, data.pretty, "application/json")
+        if doc == "":
+          return resError(Http500, "Unable to patch document '$1'." % id)
+      except:
+        return resError(Http500, "Unable to patch document '$1' - $2" % id, getCurrentExceptionMsg())
+    if origTags != tags:
+      try:
+        for t1 in jdoc["tags"].items:
+          discard LS.store.destroyTag(t1.str, id, true)
+        for t2 in tags:
+          if t2 != "":
+            LS.store.createTag(t2, id, true)
+      except:
+        return resError(Http500, "Unable to patch document '$1' - $2" % [id, getCurrentExceptionMsg()])
+  return LS.getRawDocument(id)
+
+# Main routing
+
+proc options*(req: LSRequest, LS: LiteStore, resource: string, id = ""): LSResponse =
+  case resource:
+    of "info":
+      if id != "":
+        return resError(Http404, "Info '$1' not found." % id)
+      else:
+        result.code = Http200
+        result.content = ""
+        result.headers = newHttpHeaders(TAB_HEADERS)
+        result.headers["Allow"] = "GET,OPTIONS"
+        result.headers["Access-Control-Allow-Methods"] = "GET,OPTIONS"
+    of "dir":
+      result.code = Http200
+      result.content = ""
+      result.headers = newHttpHeaders(TAB_HEADERS)
+      result.headers["Allow"] = "GET,OPTIONS"
+      result.headers["Access-Control-Allow-Methods"] = "GET,OPTIONS"
+    of "docs":
+      var folder: string
+      if id.isFolder:
+        folder = id
+      if folder.len > 0:
+        result.code = Http200
+        result.content = ""
+        if LS.readonly:
+          result.headers = newHttpHeaders(TAB_HEADERS)
+          result.headers["Allow"] = "HEAD,GET,OPTIONS"
+          result.headers["Access-Control-Allow-Methods"] = "HEAD,GET,OPTIONS"
+        else:
+          result.headers = newHttpHeaders(TAB_HEADERS)
+          result.headers["Allow"] = "HEAD,GET,OPTIONS,POST,PUT"
+          result.headers["Access-Control-Allow-Methods"] = "HEAD,GET,OPTIONS,POST,PUT"
+      elif id != "":
+        result.code = Http200
+        result.content = ""
+        if LS.readonly:
+          result.headers = newHttpHeaders(TAB_HEADERS)
+          result.headers["Allow"] = "HEAD,GET,OPTIONS"
+          result.headers["Access-Control-Allow-Methods"] = "HEAD,GET,OPTIONS"
+        else:
+          result.headers = newHttpHeaders(TAB_HEADERS)
+          result.headers["Allow"] = "HEAD,GET,OPTIONS,PUT,PATCH,DELETE"
+          result.headers["Allow-Patch"] = "application/json-patch+json"
+          result.headers["Access-Control-Allow-Methods"] = "HEAD,GET,OPTIONS,PUT,PATCH,DELETE"
+      else:
+        result.code = Http200
+        result.content = ""
+        if LS.readonly:
+          result.headers = newHttpHeaders(TAB_HEADERS)
+          result.headers["Allow"] = "HEAD,GET,OPTIONS"
+          result.headers["Access-Control-Allow-Methods"] = "HEAD,GET,OPTIONS"
+        else:
+          result.headers = newHttpHeaders(TAB_HEADERS)
+          result.headers["Allow"] = "HEAD,GET,OPTIONS,POST"
+          result.headers["Access-Control-Allow-Methods"] = "HEAD,GET,OPTIONS,POST"
+    else:
+      discard # never happens really.
+
+proc head*(req: LSRequest, LS: LiteStore, resource: string, id = ""): LSResponse =
+  var options = newQueryOptions()
+  options.select = @["documents.id AS id", "created", "modified"]
+  if id.isFolder:
+    options.folder = id
+  try:
+    parseQueryOptions(req.url.query, options);
+    if id != "" and options.folder == "":
+      result = LS.getRawDocument(id, options)
+      result.content = ""
+    else:
+      result = LS.getRawDocuments(options)
+      result.content = ""
+  except:
+    return resError(Http400, "Bad request - $1" % getCurrentExceptionMsg())
+
+proc get*(req: LSRequest, LS: LiteStore, resource: string, id = ""): LSResponse =
+  let  id = id.decodeURL
+  case resource:
+    of "docs":
+      var options = newQueryOptions()
+      if id.isFolder:
+        options.folder = id
+      if req.url.query.contains("contents=false"):
+        options.select = @["documents.id AS id", "created", "modified"]
+      try:
+        parseQueryOptions(req.url.query, options);
+        if id != "" and options.folder == "":
+          if req.url.query.contains("raw=true") or req.headers.hasKey("Accept") and req.headers["Accept"] == "application/json":
+            return LS.getRawDocument(id, options)
+          else:
+            return LS.getDocument(id, options)
+        else:
+          return LS.getRawDocuments(options)
+      except:
+        return resError(Http400, "Bad Request - $1" % getCurrentExceptionMsg())
+    of "tags":
+      var options = newQueryOptions()
+      try:
+        parseQueryOptions(req.url.query, options);
+        if id != "": 
+          return LS.getTag(id, options)
+        else:
+          return LS.getTags(options)
+      except:
+        return resError(Http400, "Bad Request - $1" % getCurrentExceptionMsg())
+    of "info":
+      if id != "":
+        return resError(Http404, "Info '$1' not found." % id)
+      return LS.getInfo()
+    else:
+      discard # never happens really.
+
+proc post*(req: LSRequest, LS: LiteStore, resource: string, id = ""): LSResponse = 
+  var ct = "text/plain"
+  if req.headers.hasKey("Content-Type"):
+    ct = req.headers["Content-Type"]
+  return LS.postDocument(req.body.strip, ct, id)
+
+proc put*(req: LSRequest, LS: LiteStore, resource: string, id = ""): LSResponse = 
+  if id != "":
+    var ct = "text/plain"
+    if req.headers.hasKey("Content-Type"):
+      ct = req.headers["Content-Type"]
+    return LS.putDocument(id, req.body.strip, ct)
+  else:
+    return resError(Http400, "Bad request: document ID must be specified in PUT requests.")
+
+proc delete*(req: LSRequest, LS: LiteStore, resource: string, id = ""): LSResponse = 
+  if id != "":
+    return LS.deleteDocument(id)
+  else:
+    return resError(Http400, "Bad request: document ID must be specified in DELETE requests.")
+
+proc patch*(req: LSRequest, LS: LiteStore, resource: string, id = ""): LSResponse = 
+  if id != "":
+    return LS.patchDocument(id, req.body)
+  else:
+    return resError(Http400, "Bad request: document ID must be specified in PATCH requests.")
+
+proc serveFile*(req: LSRequest, LS: LiteStore, id: string): LSResponse =
+  let path = LS.directory / id
+  var reqMethod = $req.reqMethod
+  if req.headers.hasKey("X-HTTP-Method-Override"):
+    reqMethod = req.headers["X-HTTP-Method-Override"]
+  case reqMethod.toUpperAscii:
+    of "OPTIONS":
+      return validate(req, LS, "dir", id, options)
+    of "GET":
+      if path.fileExists:
+        try:
+          let contents = path.readFile
+          let parts = path.splitFile
+          if CONTENT_TYPES.hasKey(parts.ext):
+            result.headers = CONTENT_TYPES[parts.ext].ctHeader
+          else:
+            result.headers = ctHeader("text/plain")
+          result.content = contents
+          result.code = Http200
+        except:
+          return resError(Http500, "Unable to read file '$1'." % path)
+      else:
+        return resError(Http404, "File '$1' not found." % path)
+    else:
+      return resError(Http405, "Method not allowed: $1" % $req.reqMethod) 
+
+proc route*(req: LSRequest, LS: LiteStore, resource = "docs", id = ""): LSResponse = 
+  var reqMethod = $req.reqMethod
+  if req.headers.hasKey("X-HTTP-Method-Override"):
+    reqMethod = req.headers["X-HTTP-Method-Override"]
+  case reqMethod.toUpperAscii:
+    of "POST":
+      if LS.readonly:
+        return resError(Http405, "Method not allowed: $1" % $req.reqMethod) 
+      return validate(req, LS, resource, id, post)
+    of "PUT":
+      if LS.readonly:
+        return resError(Http405, "Method not allowed: $1" % $req.reqMethod) 
+      return validate(req, LS, resource, id, put)
+    of "DELETE":
+      if LS.readonly:
+        return resError(Http405, "Method not allowed: $1" % $req.reqMethod) 
+      return validate(req, LS, resource, id, delete)
+    of "HEAD":
+      return validate(req, LS, resource, id, head)
+    of "OPTIONS":
+      return validate(req, LS, resource, id, options)
+    of "GET":
+      return validate(req, LS, resource, id, get)
+    of "PATCH":
+      if LS.readonly:
+        return resError(Http405, "Method not allowed: $1" % $req.reqMethod) 
+      return validate(req, LS, resource, id, patch)
+    else:
+      return resError(Http405, "Method not allowed: $1" % $req.reqMethod) 

@@ -126,23 +126,32 @@ else:
     store.rollback()
     raise newException(EInvalidTag, "Invalid Tag: $1" % tagid)
 
-proc retrieveTag*(store: Datastore, id: string, options: QueryOptions = newQueryOptions()): string =
+proc retrieveTag*(store: Datastore, id: string, options: QueryOptions = newQueryOptions()): JsonNode =
   var options = options
   options.single = true
   var query = prepareSelectTagsQuery(options)
   var raw_tag = store.db.getRow(query.sql, id)
-  return $(%[("id", %raw_tag[0]), ("documents", %(raw_tag[1].parseInt))])
+  return %[("id", %raw_tag[0]), ("documents", %(raw_tag[1].parseInt))]
 
-proc retrieveTags*(store: Datastore, options: QueryOptions = newQueryOptions()): string =
+proc retrieveTags*(store: Datastore, options: QueryOptions = newQueryOptions()): JsonNode =
   var query = prepareSelectTagsQuery(options)
-  var raw_tags = store.db.getAllRows(query.sql)
+  var raw_tags: seq[Row]
+  if (options.like.len > 0):
+    raw_tags = store.db.getAllRows(query.sql, options.like.replace("*", "%"))
+  else:
+    raw_tags = store.db.getAllRows(query.sql)
   var tags = newSeq[JsonNode](0)
   for tag in raw_tags:
     tags.add(%[("id", %tag[0]), ("documents", %(tag[1].parseInt))])
-  return $(%tags)
+  return %tags
 
-proc countTags*(store: Datastore): int64 =
-  return store.db.getRow(SQL_COUNT_TAGS)[0].parseInt
+proc countTags*(store: Datastore, q = "", like = ""): int64 =
+  var query = SQL_COUNT_TAGS
+  if q.len > 0:
+    query = q.sql
+  if like.len > 0:
+    return store.db.getRow(query, like)[0].parseInt
+  return store.db.getRow(query)[0].parseInt
 
 proc retrieveTagsWithTotals*(store: Datastore): JsonNode =
   var data = store.db.getAllRows(SQL_SELECT_TAGS_WITH_TOTALS)

@@ -13,10 +13,11 @@ types,
   utils, 
   api_v1,
   api_v2,
-  api_v3
+  api_v3,
+  api_v4
 
 export 
-  api_v3
+  api_v4
 
 proc getReqInfo(req: LSRequest): string =
   var url = req.url.path
@@ -32,7 +33,17 @@ LOG.info("Exiting...")
   quit()
 
 proc processApiUrl(req: LSRequest, LS: LiteStore, info: ResourceInfo): LSResponse = 
-  if info.version == "v3":
+  if info.version == "v4":
+    if info.resource.match(peg"^docs / info / tags$"):
+      return api_v4.route(req, LS, info.resource, info.id)
+    elif info.resource.match(peg"^dir$"):
+      if LS.directory.len > 0:
+        return api_v4.serveFile(req, LS, info.id)
+      else:
+        return resError(Http400, "Bad Request - Not serving any directory." % info.version)
+    else:
+      return resError(Http400, "Bad Request - Invalid resource: $1" % info.resource)
+  elif info.version == "v3":
     if info.resource.match(peg"^docs / info$"):
       return api_v3.route(req, LS, info.resource, info.id)
     elif info.resource.match(peg"^dir$"):
@@ -63,7 +74,7 @@ return resError(Http400, "Bad Request - Not serving any directory." % info.version)
     else:
       return resError(Http400, "Bad Request - Invalid resource: $1" % info.resource)
   else:
-    if info.version == "v1" or info.version == "v2" or info.version == "v3":
+    if info.version == "v1" or info.version == "v2" or info.version == "v3" or info.version == "v4":
       return resError(Http400, "Bad Request - Invalid API version: $1" % info.version)
     else:
       if info.resource.decodeURL.strip == "":
@@ -79,7 +90,7 @@ op
   try: 
     var info: ResourceInfo
     req.route peg"^\/?$":
-      info.version = "v3"
+      info.version = "v4"
       info.resource = "info"
       return req.processApiUrl(LS, info)
     req.route peg"^\/favicon.ico$":
@@ -88,7 +99,7 @@ result.content = LS.favicon
       result.headers = ctHeader("image/x-icon")
       return result
     req.route PEG_DEFAULT_URL:
-      info.version = "v3"
+      info.version = "v4"
       info.resource = matches[0]
       info.id = matches[1]
       return req.processApiUrl(LS, info)

@@ -36,6 +36,7 @@ limit*: int
     offset*: int           
     orderby*: string      
     tags*: string
+    like*: string
     folder*: string
     search*: string
   TagExpression* = object
@@ -109,4 +110,4 @@ "Server": LS.appname & "/" & LS.appversion
 }
 
 proc newQueryOptions*(): QueryOptions =
-  return QueryOptions(select: @["documents.id AS id", "documents.data AS data", "content_type", "binary", "searchable", "created", "modified"], single: false, limit: 0, offset: 0, orderby: "", tags: "", search: "", folder: "", jsonFilter: "", jsonSelect: newSeq[tuple[path: string, alias: string]](), tables: newSeq[string]())
+  return QueryOptions(select: @["documents.id AS id", "documents.data AS data", "content_type", "binary", "searchable", "created", "modified"], single: false, limit: 0, offset: 0, orderby: "", tags: "", search: "", folder: "", like: "", jsonFilter: "", jsonSelect: newSeq[tuple[path: string, alias: string]](), tables: newSeq[string]())

@@ -98,15 +98,24 @@ result = result & "OFFSET " & $options.offset & " "
   LOG.debug(result.replace("$", "$$"))
  
 proc prepareSelectTagsQuery*(options: QueryOptions): string =
-  result = "SELECT tag_id, COUNT(document_id) "
-  result = result & "FROM tags "
+  var group = true
+  if options.select.len > 0 and options.select[0] == "COUNT(tag_id)":
+    result  = "SELECT COUNT(DISTINCT tag_id) "
+    result = result & "FROM tags "
+    group = false
+  else:
+    result = "SELECT tag_id, COUNT(document_id) "
+    result = result & "FROM tags "
   if options.single:
     result = result & "WHERE tag_id = ?"
-  result = result & "GROUP BY tag_id"
-  if options.orderby.len > 0:
-    result = result & "ORDER BY " & options.orderby&" " 
+  elif options.like.len > 0:
+    result = result & "WHERE tag_id LIKE ? " 
+  if group:
+    result = result & "GROUP BY tag_id "
   if options.limit > 0:
     result = result & "LIMIT " & $options.limit & " "
+  if options.offset > 0:
+    result = result & "OFFSET " & $options.offset & " "
   LOG.debug(result.replace("$", "$$"))
 
 proc prepareJsonDocument*(store:Datastore, doc: Row, options: QueryOptions): JsonNode =
@@ -223,6 +232,9 @@ result.headers = ctJsonHeader()
 
 proc resDocumentNotFound*(id: string): LSResponse =
   resError(Http404, "Document '$1' not found." % id)
+
+proc resTagNotFound*(id: string): LSResponse =
+  resError(Http404, "Tag '$1' not found." % id)
 
 proc eWarn*() =
   var e = getCurrentException()

@@ -1,6 +1,6 @@ 
 [Package]
 name          = "litestore"
-version       = "1.4.1"
+version       = "1.5.0"
 author        = "Fabio Cevasco"
 description   = "Self-contained, lightweight, RESTful document store."
 license       = "MIT"