curl - HTTP Client und Datentransfer¶

generieren

Umfassende Curl-Befehle für HTTP-Anfragen, API-Tests und Datenübertragung auf allen Plattformen.

Grundlegende HTTP Anfragen¶

GET Anträge¶

Command	Description
`curl https://api.example.com`	Basic GET request
`curl -v https://api.example.com`	Verbose output with headers
`curl -i https://api.example.com`	Include response headers
`curl -I https://api.example.com`	HEAD request only
`curl -L https://example.com`	Follow redirects

POST Anträge¶

Command	Description
`curl -X POST https://api.example.com`	Basic POST request
`curl -d "data" https://api.example.com`	POST with data
`curl -d @file.json https://api.example.com`	POST data from file
`curl -F "file=@upload.txt" https://api.example.com`	File upload

Andere HTTP Methoden¶

Command	Description
`curl -X PUT -d "data" https://api.example.com`	PUT request
`curl -X DELETE https://api.example.com/item/1`	DELETE request
`curl -X PATCH -d "data" https://api.example.com`	PATCH request

Kopfzeilen und Authentication¶

Benutzerdefinierte Kopfzeilen¶

Command	Description
`curl -H "Content-Type: application/json" url`	Set content type
`curl -H "Authorization: Bearer token" url`	Bearer token auth
`curl -H "User-Agent: MyApp/1.0" url`	Custom user agent
`curl -H "Accept: application/xml" url`	Accept header

Authentifizierungsmethoden¶

Command	Description
`curl -u username:password url`	Basic authentication
`curl -u username url`	Prompt for password
`curl --oauth2-bearer token url`	OAuth2 bearer token
`curl --digest -u user:pass url`	Digest authentication

API Schlüsselauthentifizierung¶

```bash

API key in header¶

curl -H "X-API-Key: your-api-key" https://api.example.com

API key in query parameter¶

curl "https://api.example.com?api_key=your-api-key"

Multiple headers¶

curl -H "Authorization: Bearer token" \ -H "Content-Type: application/json" \ https://api.example.com ```_

Datenformate¶

JSON Daten¶

```bash

POST JSON data¶

curl -X POST \ -H "Content-Type: application/json" \ -d '\\{"name":"John","age":30\\}' \ https://api.example.com/users

JSON from file¶

curl -X POST \ -H "Content-Type: application/json" \ -d @data.json \ https://api.example.com/users ```_

Formular-Daten¶

```bash

URL-encoded form data¶

curl -d "name=John&age=30" https://api.example.com/users

Multipart form data¶

curl -F "name=John" -F "age=30" https://api.example.com/users

File upload with form data¶

curl -F "file=@document.pdf" \ -F "description=Important document" \ https://api.example.com/upload ```_

XML Daten¶

```bash

POST XML data¶

curl -X POST \ -H "Content-Type: application/xml" \ -d 'John30' \ https://api.example.com/users ```_

Dateioperationen¶

Dateien herunterladen¶

Command	Description
`curl -O https://example.com/file.zip`	Download with original name
`curl -o myfile.zip https://example.com/file.zip`	Download with custom name
`curl -C - -O https://example.com/file.zip`	Resume interrupted download
`curl --limit-rate 100k -O url`	Limit download speed

Dateien hochladen¶

Command	Description
`curl -T file.txt ftp://server/path/`	Upload via FTP
`curl -F "file=@upload.txt" url`	HTTP file upload
`curl --upload-file file.txt url`	PUT file upload

Mehrere Dateien¶

```bash

Download multiple files¶

curl -O https://example.com/file1.zip -O https://example.com/file2.zip

Upload multiple files¶

curl -F "file1=@doc1.pdf" -F "file2=@doc2.pdf" https://api.example.com/upload ```_

Erweiterte Optionen¶

Timeouts und Retries¶

Command	Description
`curl --connect-timeout 10 url`	Connection timeout (seconds)
`curl --max-time 30 url`	Maximum total time
`curl --retry 3 url`	Retry on failure
`curl --retry-delay 5 url`	Delay between retries

SSL/TLS Optionen¶

Command	Description
`curl -k url`	Ignore SSL certificate errors
`curl --cacert ca.pem url`	Use custom CA certificate
`curl --cert client.pem url`	Use client certificate
`curl --tlsv1.2 url`	Force TLS version

Proxy und Netzwerk¶

Command	Description
`curl --proxy proxy.example.com:8080 url`	Use HTTP proxy
`curl --socks5 proxy.example.com:1080 url`	Use SOCKS5 proxy
`curl --interface eth0 url`	Use specific network interface
`curl --dns-servers 8.8.8.8 url`	Use custom DNS servers

Ausgabe und Formatierung¶

Ausgangssteuerung¶

Command	Description
`curl -s url`	Silent mode (no progress)
`curl -S url`	Show errors even in silent mode
`curl -o /dev/null url`	Discard output
`curl -w "%\\{http_code\\}" url`	Show only HTTP status code

Antwort¶

```bash

Get detailed timing information¶

curl -w "@curl-format.txt" https://example.com

curl-format.txt content:¶

time_namelookup: %\\{time_namelookup\\}\n¶

time_connect: %\\{time_connect\\}\n¶

time_appconnect: %\\{time_appconnect\\}\n¶

time_pretransfer: %\\{time_pretransfer\\}\n¶

time_redirect: %\\{time_redirect\\}\n¶

time_starttransfer: %\\{time_starttransfer\\}\n¶

----------\n¶

time_total: %\\{time_total\\}\n¶

```_

JSON Verarbeitung¶

```bash

Pretty print JSON with jq¶

curl -s https://api.example.com/users|jq '.'

Extract specific fields¶

curl -s https://api.example.com/users|jq '.[]|.name'

Filter results¶

curl -s https://api.example.com/users|jq '.[]|select(.age > 25)' ```_

Prüfung und Debugging¶

API Testing¶

```bash

Test REST API endpoints¶

curl -X GET https://api.example.com/users curl -X POST -d '\\{"name":"John"\\}' https://api.example.com/users curl -X PUT -d '\\{"name":"Jane"\\}' https://api.example.com/users/1 curl -X DELETE https://api.example.com/users/1

Test with different content types¶

curl -H "Accept: application/json" https://api.example.com/users curl -H "Accept: application/xml" https://api.example.com/users ```_

Leistungsprüfung¶

```bash

Measure response time¶

curl -w "Total time: %\\{time_total\\}s\n" -o /dev/null -s https://example.com

Test multiple requests¶

for i in \\{1..10\\}; do curl -w "%\\{time_total\\}\n" -o /dev/null -s https://example.com done ```_

Fehlerbehebung¶

```bash

Check HTTP status codes¶

http_code=$(curl -s -o /dev/null -w "%\\{http_code\\}" https://example.com) if [ $http_code -eq 200 ]; then echo "Success" else echo "Error: HTTP $http_code" fi ```_

Konfiguration und Skripte¶

Datei konfigurieren¶

```bash

~/.curlrc configuration file¶

user-agent = "MyApp/1.0" connect-timeout = 10 max-time = 30 show-error silent ```_

Bash Schrift¶

```bash

!/bin/bash¶

API testing script¶

BASE_URL="https://api.example.com" API_KEY="your-api-key"

Function to make authenticated requests¶

api_request() \\{ local method=$1 local endpoint=$2 local data=$3

curl -X "$method" \
     -H "Authorization: Bearer $API_KEY" \
     -H "Content-Type: application/json" \
     $\\\\{data:+-d "$data"\\\\} \
     "$BASE_URL$endpoint"

\\}

Usage examples¶

api_request GET "/users" api_request POST "/users" '\\{"name":"John","email":"john@example.com"\\}' ```_

Sicherheit Best Practices¶

Sichere Authentifizierung¶

```bash

Use environment variables for sensitive data¶

export API_TOKEN="your-secret-token" curl -H "Authorization: Bearer $API_TOKEN" https://api.example.com

Read credentials from file¶

curl -K credentials.txt https://api.example.com

credentials.txt:¶

header = "Authorization: Bearer your-token"¶

```_

Zertifikatskontrolle¶

```bash

Always verify SSL certificates in production¶

curl --cacert /path/to/ca-bundle.crt https://api.example.com

For development only (not recommended for production)¶

curl -k https://self-signed.example.com ```_

Allgemeine Anwendungsfälle¶

Web Scraping¶

```bash

Download webpage¶

curl -L https://example.com > page.html

Follow redirects and save cookies¶

curl -L -c cookies.txt -b cookies.txt https://example.com

Set user agent to avoid blocking¶

curl -H "User-Agent: Mozilla/5.0 (compatible; bot)" https://example.com ```_

API Integration¶

```bash

GitHub API example¶

curl -H "Authorization: token your-github-token" \ https://api.github.com/user/repos

Weather API example¶

curl "https://api.openweathermap.org/data/2.5/weather?q=London&appid=your-api-key"

Slack webhook example¶

curl -X POST \ -H "Content-Type: application/json" \ -d '\\{"text":"Hello from curl!"\\}' \ https://hooks.slack.com/services/YOUR/SLACK/WEBHOOK ```_

Dateiübertragung¶

```bash

Upload to cloud storage¶

curl -X PUT \ -H "Authorization: Bearer token" \ --upload-file document.pdf \ https://api.storage.com/files/document.pdf

Download with progress bar¶

curl --progress-bar -O https://example.com/largefile.zip ```_

Fehlerbehebung¶

Gemeinsame Themen¶

Problem	Solution
SSL certificate errors	Use `-k` for testing, fix certificates for production
Connection timeout	Increase `--connect-timeout` value
Slow downloads	Use `--limit-rate` to control bandwidth
Authentication failures	Check credentials and authentication method

Debugging Commands¶

```bash

Verbose output for debugging¶

curl -v https://example.com

Trace all network activity¶

curl --trace trace.txt https://example.com

Show only headers¶

curl -I https://example.com

Test connectivity¶

curl -I --connect-timeout 5 https://example.com ```_