W3cubDocs

/Nim

Module cgi

This module implements helper procs for CGI applications. Example:

import strtabs, cgi

# Fill the values when debugging:
when debug:
  setTestData("name", "Klaus", "password", "123456")
# read the data into `myData`
var myData = readData()
# check that the data's variable names are "name" or "password"
validateData(myData, "name", "password")
# start generating content:
writeContentType()
# generate content:
write(stdout, "<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01//EN\">\n")
write(stdout, "<html><head><title>Test</title></head><body>\n")
writeLine(stdout, "your name: " & myData["name"])
writeLine(stdout, "your password: " & myData["password"])
writeLine(stdout, "</body></html>")

Imports

strutils, os, strtabs, cookies

Types

CgiError = object of IOError
exception that is raised if a CGI error occurs 
RequestMethod = enum
  methodNone,                 ## no REQUEST_METHOD environment variable
  methodPost,                 ## query uses the POST method
  methodGet                   ## query uses the GET method
the used request method

Procs

proc encodeUrl(s: string): string {.raises: [], tags: [].}
Encodes a value to be HTTP safe: This means that characters in the set {'A'..'Z', 'a'..'z', '0'..'9', '_'} are carried over to the result, a space is converted to '+' and every other character is encoded as '%xx' where xx denotes its hexadecimal value. 
proc decodeUrl(s: string): string {.raises: [], tags: [].}
Decodes a value from its HTTP representation: This means that a '+' is converted to a space, '%xx' (where xx denotes a hexadecimal value) is converted to the character with ordinal number xx, and and every other character is carried over. 
proc xmlEncode(s: string): string {.raises: [], tags: [].}
Encodes a value to be XML safe:
  • " is replaced by &quot;
  • < is replaced by &lt;
  • > is replaced by &gt;
  • & is replaced by &amp;
  • every other character is carried over.
proc cgiError(msg: string) {.noreturn, raises: [CgiError], tags: [].}
raises an ECgi exception with message msg. 
proc readData(allowedMethods: set[RequestMethod] = {methodNone, methodPost, methodGet}): StringTableRef {.
    raises: [CgiError, OverflowError, ValueError, IOError],
    tags: [ReadEnvEffect, ReadIOEffect].}
Read CGI data. If the client does not use a method listed in the allowedMethods set, an ECgi exception is raised. 
proc validateData(data: StringTableRef; validKeys: varargs[string]) {.
    raises: [CgiError], tags: [].}
validates data; raises ECgi if this fails. This checks that each variable name of the CGI data occurs in the validKeys array. 
proc getContentLength(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the CONTENT_LENGTH environment variable 
proc getContentType(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the CONTENT_TYPE environment variable 
proc getDocumentRoot(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the DOCUMENT_ROOT environment variable 
proc getGatewayInterface(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the GATEWAY_INTERFACE environment variable 
proc getHttpAccept(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the HTTP_ACCEPT environment variable 
proc getHttpAcceptCharset(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the HTTP_ACCEPT_CHARSET environment variable 
proc getHttpAcceptEncoding(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the HTTP_ACCEPT_ENCODING environment variable 
proc getHttpAcceptLanguage(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the HTTP_ACCEPT_LANGUAGE environment variable 
proc getHttpConnection(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the HTTP_CONNECTION environment variable 
proc getHttpCookie(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the HTTP_COOKIE environment variable 
proc getHttpHost(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the HTTP_HOST environment variable 
proc getHttpReferer(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the HTTP_REFERER environment variable 
proc getHttpUserAgent(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the HTTP_USER_AGENT environment variable 
proc getPathInfo(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the PATH_INFO environment variable 
proc getPathTranslated(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the PATH_TRANSLATED environment variable 
proc getQueryString(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the QUERY_STRING environment variable 
proc getRemoteAddr(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the REMOTE_ADDR environment variable 
proc getRemoteHost(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the REMOTE_HOST environment variable 
proc getRemoteIdent(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the REMOTE_IDENT environment variable 
proc getRemotePort(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the REMOTE_PORT environment variable 
proc getRemoteUser(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the REMOTE_USER environment variable 
proc getRequestMethod(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the REQUEST_METHOD environment variable 
proc getRequestURI(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the REQUEST_URI environment variable 
proc getScriptFilename(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the SCRIPT_FILENAME environment variable 
proc getScriptName(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the SCRIPT_NAME environment variable 
proc getServerAddr(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the SERVER_ADDR environment variable 
proc getServerAdmin(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the SERVER_ADMIN environment variable 
proc getServerName(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the SERVER_NAME environment variable 
proc getServerPort(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the SERVER_PORT environment variable 
proc getServerProtocol(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the SERVER_PROTOCOL environment variable 
proc getServerSignature(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the SERVER_SIGNATURE environment variable 
proc getServerSoftware(): string {.raises: [], tags: [ReadEnvEffect].}
returns contents of the SERVER_SOFTWARE environment variable 
proc setTestData(keysvalues: varargs[string]) {.raises: [OSError],
    tags: [WriteEnvEffect].}
fills the appropriate environment variables to test your CGI application. This can only simulate the 'GET' request method. keysvalues should provide embedded (name, value)-pairs. Example:
setTestData("name", "Hanz", "password", "12345")
proc writeContentType() {.raises: [IOError], tags: [WriteIOEffect].}
call this before starting to send your HTML data to stdout. This implements this part of the CGI protocol:
write(stdout, "Content-type: text/html\n\n")
proc writeErrorMessage(data: string) {.raises: [IOError], tags: [WriteIOEffect].}
Tries to reset browser state and writes data to stdout in <plaintext> tag. 
proc setStackTraceStdout() {.raises: [], tags: [].}
Makes Nim output stacktraces to stdout, instead of server log. 
proc setStackTraceNewLine() {.deprecated, raises: [], tags: [].}
Makes Nim output stacktraces to stdout, instead of server log. Depracated alias for setStackTraceStdout. 
proc setCookie(name, value: string) {.raises: [IOError], tags: [WriteIOEffect].}
Sets a cookie. 
proc getCookie(name: string): TaintedString {.raises: [], tags: [ReadEnvEffect].}
Gets a cookie. If no cookie of name exists, "" is returned. 
proc existsCookie(name: string): bool {.raises: [], tags: [ReadEnvEffect].}
Checks if a cookie of name exists.

Iterators

iterator decodeData(data: string): tuple[key, value: TaintedString] {.
    raises: [CgiError], tags: [].}
Reads and decodes CGI data and yields the (name, value) pairs the data consists of. 
iterator decodeData(allowedMethods: set[RequestMethod] = {methodNone, methodPost,
    methodGet}): tuple[key, value: TaintedString] {.
    raises: [CgiError, OverflowError, ValueError, IOError],
    tags: [ReadEnvEffect, ReadIOEffect].}
Reads and decodes CGI data and yields the (name, value) pairs the data consists of. If the client does not use a method listed in the allowedMethods set, an ECgi exception is raised.

© 2006–2017 Andreas Rumpf
Licensed under the MIT License.
https://nim-lang.org/docs/cgi.html